Recent Trends in "Manels" and Gender Representation Among Panelists at North American Annual Radiation Oncology Meetings

PURPOSE

Achieving gender equity in radiation oncology is an important goal, as a smaller proportion of women enter radiation oncology residency compared with those graduating from medical school. As invited speaking opportunities at academic medical conferences are vital for promotion/tenure, we investigated the prevalence of all-men panels ("manels") at American Society for Radiation Oncology (ASTRO) and Canadian Society of Radiation Oncology (CARO) annual meetings.

METHODS AND MATERIALS

Using ASTRO and CARO online meeting programs, 2018 to 2021 faculty information was obtained, including gender, panel role (chair vs nonchair), type of session, and topic. Primary outcomes included percentage of manels and proportion of female panelists over time. Representation of women among chairs was also evaluated.

RESULTS

Over the 4-year study period across both conferences, a total of 765 panel sessions were held with 2973 faculty members, of whom 1287 (43.3%) were women. Of these sessions, 127 of 765 (16.6%) were manels. ASTRO meetings had 1169 of 2742 (42.6%) female faculty members and held 107 of 680 (15.7%) manels, whereas CARO meetings had 118 of 231 (51.1%) female faculty and held 20 of 85 manels (23.5%). From 2018 to 2021, the proportion of manels decreased at ASTRO and CARO meetings from 25.6% to 8.2% (P < .001) and from 29.6% to 15.0% (P = .130), respectively. The role of chair was majority male in every year from 2018 to 2021 at ASTRO meetings (58.6% overall), but more balanced at CARO meetings (48.0% overall). Among session types, the highest proportion of manels was observed for scientific sessions (19.1%, P = .011) at ASTRO meetings and leadership sessions (29.4%, P = .533) at CARO meetings. The lowest proportion of female panelists was on genitourinary cancer topics at ASTRO meetings (31.9%, P = .018) and physics topics at CARO meetings (40.4%, P = .085).

CONCLUSIONS

During the study period, the proportion of female panelists increased with a corresponding decrease in manels. ASTRO and CARO should strive for further involvement of women and the elimination of manels whenever possible.

Efficacy and Safety of Dose-Escalated Alectinib in Patients With Metastatic ALK-Positive NSCLC and Central Nervous System Relapse on Standard-Dose Alectinib

Introduction

Central nervous system (CNS) metastases remain a common challenge in patients with ALK-positive NSCLC. We previously reported reinduction of CNS responses using dose-intensified alectinib in two patients with CNS progression on standard-dose alectinib. Nevertheless, this strategy has not been assessed in larger cohorts.

Methods

Patients were eligible for this retrospective study if they had metastatic ALK-positive NSCLC with CNS relapse on alectinib 600 mg twice daily dosing and subsequently received escalated dosing (900 mg twice daily) of alectinib. CNS efficacy was assessed per the modified Response Evaluation Criteria in Solid Tumors version 1.1.

Results

Among 27 patients, median duration of dose-escalated alectinib was 7.7 months (95% confidence interval [CI]: 4.8-10.9), with median overall time-to-progression (TTP) of 7.1 months (95% CI: 4.4-9.6). Among 25 CNS response-assessable patients, CNS objective response rate was 12.0% (95% CI: 2.5-31.2) and CNS disease control rate was 92.0% (95% CI: 74.0-99.0), with median CNS duration of disease control of 5.3 months (95% CI: 3.4-8.3) and median CNS TTP of 7.1 months (95% CI: 4.4-9.6). Among four patients with measurable CNS disease at baseline, three experienced a best intracranial response of stable disease and one experienced intracranial partial response with CNS TTP ranging from 4.1 to 7.7 months. No patient required drug discontinuation due to treatment-related adverse event or experienced grade 3 or higher treatment-related adverse events.

Conclusions

Dose-intensified alectinib was found to have tolerability and activity in patients with ALK-positive NSCLC who experienced CNS relapse on standard-dose alectinib and represents one clinically viable strategy for this population.

Circulating and Imaging Biomarkers of Radium-223 Response in Metastatic Castration-Resistant Prostate Cancer

PURPOSE

Radium-223 improves overall survival (OS) and reduces skeletal events in patients with bone metastatic castration-resistant prostate cancer (CRPC), but relevant biomarkers are lacking. We evaluated automated bone scan index (aBSI) and circulating tumor cell (CTC) analyses as potential biomarkers of prognosis and activity.

PATIENTS AND METHODS

Patients with bone metastatic CRPC were enrolled on a prospective single-arm study of standard radium-223. 99mTc-MDP bone scan images at baseline, 2 months, and 6 months were quantitated using aBSI. CTCs at baseline, 1 month, and 2 months were enumerated and assessed for RNA expression of prostate cancer-specific genes using microfluidic enrichment followed by droplet digital polymerase chain reaction.

RESULTS

The median OS was 21.3 months in 22 patients. Lower baseline aBSI and minimal change in aBSI (<+0.7) from baseline to 2 months were each associated with better OS (P = .00341 and P = .0139, respectively). The higher baseline CTC count of ≥5 CTC/7.5 mL was associated with worse OS (median, 10.1 v 32.9 months; P = .00568). CTCs declined at 2 months in four of 15 patients with detectable baseline CTCs. Among individual genes in CTCs, baseline expression of the splice variant AR-V7 was significantly associated with worse OS (hazard ratio, 5.20 [95% CI, 1.657 to 16.31]; P = .00195). Baseline detectable AR-V7, higher aBSI, and CTC count ≥5 CTC/7.5 mL continued to have a significant independent negative impact on OS after controlling for prostate-specific antigen or alkaline phosphatase.

CONCLUSION

Quantitative bone scan assessment with aBSI and CTC analyses are prognostic markers in patients treated with radium-223. AR-V7 expression in CTCs is a particularly promising prognostic biomarker and warrants validation in larger cohorts.

Health-Related Quality of Life Analysis in Patients with Non-Functioning Pituitary Macroadenomas Treated with Transsphenoidal Surgery with or without Radiation Therapy

PURPOSE/OBJECTIVE(S)

The quality of life (QoL) impact of multidisciplinary treatment for patients with nonfunctioning pituitary macroadenomas (NFPMA) is unclear. We sought to assess patient-reported QoL in our institutional experience using a cross-sectional survey.

MATERIALS/METHODS

We identified 488 patients with NFPMA treated at our institution from 1980-2010 who underwent transsphenoidal surgery (TSS) with or without adjuvant salvage therapy with radiation therapy (RT) and/or surgery. The following validated patient-reported outcome measures were collected: the RAND Short Form-36 Health Survey (SF-36), the Multidimensional Fatigue Inventory (MFI-20), and the Cognitive Failures Questionnaire (CFQ). Clinical characteristics of patients who did and did not receive RT were compared using Wilcoxon rank-sum test or Fisher's exact test. We used multivariable linear regression and reported mean score differences between comparison groups.

RESULTS

The response rate to survey invitation was 47% (229 patients). Median age at the time of initial TSS was 55 years (18-85 years). 35% of patients were female. 25% of participants received RT a median of 2.0 years (0.1-22.5) after initial TSS, and 15% of patients had >1 additional surgery after initial TSS. The patients who received RT were younger (median age 46 v 58, p < 0.0001), had larger tumors (28 mm v 22 mm, p < 0.0001) and were more likely to have visual symptoms (65% v 34%, p = 0.0002 and were more likely to have hypopituitarism (93% v 62%, p < 0.0001). Patients completed QoL questionnaires a median of 7.7 years (1.3-29.9) after initial TSS, at which point patients with hypopituitarism reported worse energy and fatigue (SF-36 Energy/Fatigue: -7.95, p = 0.026) and cognitive function (CFQ: 5.35, p = 0.026). Patients who received RT reported significantly worse general health (SF-36 General Health Perceptions subscale: -8.44, p = 0.032), physical health (SF-36 Physical Health Composite: -4.07, p = 0.042), physical fatigue (MFI-20 Physical Fatigue subscale: 11.68, p = 0.024) and cognitive functioning (CFQ: 6.64, p = 0.0298). The largest QoL differences were seen in patients who experienced a financial stressor after treatment, independent of treatment type. These patients reported significantly worse QoL for most outcomes, including emotional well-being, physical and mental health, social functioning, energy level, and motivation. RT was associated with self-reported unstable/insecure or very dire financial circumstances (28% v 7%, p < 0.0001).

CONCLUSION

Hypopituitarism, radiation therapy after TSS, and financial stressors are associated with decreased QoL in several domains, and these factors may identify patients who can benefit most from early multidisciplinary care, including financial counseling and additional psychosocial support.

Prostate Advanced Radiation Technologies Investigating Quality of Life (PARTIQoL): A Phase III Randomized Clinical Trial of Proton Therapy vs. IMRT for Low or Intermediate Risk Prostate Cancer

PURPOSE/OBJECTIVE(S)

Prostate cancer is the most common non-cutaneous cancer diagnosed among men in the United States, and the majority of patients are diagnosed with localized disease. Men with localized prostate cancer have several treatment options including external beam radiotherapy with either photons or protons. Proton beam therapy (PBT) has certain dosimetric advantages and the potential to reduce treatment-associated morbidity and improve oncologic outcomes, but current PBT is significantly more costly than intensity-modulated radiotherapy (IMRT). The PARTIQoL trial (NCT01617161) is the first multicenter phase 3 randomized trial comparing protons to photons in the treatment of localized prostate cancer.

MATERIALS/METHODS

Patients with low or intermediate risk prostate cancer (Stage T1c-T2c, PSA < 20, Gleason score ≤ 7) are randomized to receive either PBT or IMRT, with targeted recruitment efforts for minority populations. A companion registry study has concurrently enrolled patients who declined randomization or whose insurance denied coverage for PBT. Patients are stratified by clinical site, age, use of rectal spacer, and fractionation schedule (conventional fractionation: 79.2 Gy in 44 fractions vs moderate hypofractionation: 70.0 Gy in 28 fractions). Participants are followed longitudinally to assess patient-reported outcomes (PROs) of bowel, urinary, and erectile function for 60 months after completion of radiotherapy (with an option for additional follow up through 10 years). Participants may also participate in correlative studies, including serial CT imaging during treatment and analyses of biopsy tissue, blood and urine specimens. The primary objective is to compare PROs of bowel function using the EPIC score at 24 months following completion of radiation. Secondary objectives are to assess treatment-related differences in urinary and erectile functions, adverse events, efficacy endpoints (biochemical control, metastasis-free survival, disease-specific survival, and overall survival), health state utilities, perceptions of care, late effects, cost-effectiveness, association between radiotherapy dose distribution and PROs, and to identify biomarkers of radiation response and toxicity.

RESULTS

The randomized trial has completed accrual, with 450 patients enrolled at 27 sites between June 2012 and November 2021. 20.3% of patients enrolled are non-white. Accrual on the companion registry is active, with 354 patients enrolled as of February 2023.

CONCLUSION

Follow-up for the primary endpoint on the randomized trial will be reached in 2024. The PARTIQoL randomized clinical trial will rigorously assess the clinical benefits of PBT relative to IMRT and results will inform decision making by patients, providers, policymakers, and payers.

Multi-Institutional Phase I Feasibility Trial of Vertebral Body Sparing CSI for Pediatric Brain Tumors

PURPOSE/OBJECTIVE(S)

Craniospinal irradiation (CSI) is an essential part of curative treatment for several pediatric brain tumors. Proton CSI allows for sparing of the organs anterior to the vertebral bodies (VBs), but this technique still includes the entire VB in the target for growing children. providing no advantage in marrow sparing or adverse effects on growth. Advances in proton therapy including Proton Beam Scanning (PBS) allow for delivery of proton CSI with substantial vertebral body sparing (VBS). We sought to determine the feasibility of VBS CSI using PBS based on the effects on tumor control and growth, and the occurrence of grade III/IV hematologic toxicity.

MATERIALS/METHODS

Clinical and treatment characteristics were recorded for 20 pediatric patients with medulloblastoma (n = 14) or germ cell tumor (GCT) (n = 6) who received proton VBS CSI without concurrent chemotherapy or with concurrent single-agent vincristine in a multi-institutional clinical trial. The following standard variables were extracted for each patient: age, histology, radiation dose, chemotherapy regimen, and growth hormone replacement status. Complete blood counts (CBC) with differential and data on height/weight were recorded at baseline pre-RT, weekly during RT, and after completion of cancer treatment. Hematologic toxicity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 4 (CTCAE v4).

RESULTS

Median age of 13 male and 7 female patients receiving proton VBS CSI was 10 years (range: 5.1 - 15.1). All GCT patients (n = 6, 30%) received pre-RT chemo. Median CSI dose was 23.4 Gy (range: 21.0 - 37.8), and total dose to tumor bed was 54 Gy in 18 patients (90%) while 2 patients with pure germinoma received a total dose of 36 and 37.5 Gy, respectively. 11 patients (55%) did not receive concurrent vincristine. At a median follow up of 26.4 months (range: 12.5 - 56.3) from the start of RT, no patients relapsed. 17 patients (85%) developed grade ≥3 hematologic toxicity including grade 3 lymphopenia (n = 16), leukopenia (n = 9), neutropenia (n = 8), anemia (n = 1), and grade 4 neutropenia (n = 1). The patient who developed grade 4 neutropenia had low white blood counts prior to RT. 14 patients (70%) received post-RT chemo. No patients required platelet transfusion during RT. Those findings are similar to historical controls. 4 patients started growth hormone replacement therapy after RT. No patients developed spine deformities after the completion of treatment.

CONCLUSION

Proton VBS CSI is a feasible and well tolerated treatment for children with brain tumors. Longer follow up is needed to assess for late effects on tumor control. It is too early to assess for height in this cohort but for the patients that had longer follow up, normal height was achieved.

Association between Liver Metastases and Treatment Response in Patients with Metastatic, Microsatellite Stable Colorectal Cancer Treated with Radiation Therapy and Dual Immune Checkpoint Blockade

PURPOSE/OBJECTIVE(S)

Most patients with metastatic colorectal cancer (CRC) have microsatellite stable (MSS) disease with a limited response to immune checkpoint inhibitors (ICIs). In our phase 2 trial (NCT03104439), 27 patients with metastatic MSS CRC received ipilimumab, nivolumab, and RT (24 Gy/3 fractions) on C2D1 with a disease control rate (DCR) of 37% (10/27) and overall response rate (ORR) of 15% (4/27). Our follow up phase 2 study with ipilimumab, nivolumab, and RT moved to C1D1 (NCT04361162) showed a DCR of 33% (10/30) and an ORR of 13% (4/30). Clinical and preclinical data suggest liver metastases are less responsive to systemic ICIs and complementary liver-directed RT can potentially overcome this effect. To address this, we investigated the association between liver metastases and response rates among patients treated with and without liver-directed RT in a pooled analysis of our phase 2 studies of nivolumab and ipilimumab with RT.

MATERIALS/METHODS

In this pooled secondary analysis of two open-label, single-arm, phase 2 studies, eligible patients had metastatic MSS CRC, ECOG PS 0-1, and progressed on at least one line of chemotherapy. Treatment consisted of ipilimumab 1 mg/kg q6weeks for 4 cycles, nivolumab 240 mg q2weeks on a 6-week cycle, and RT (24 Gy/3 fractions) on C1D1 or C2D1 to one site. Responses were defined outside of the RT field by RECIST 1.1 with centrally reviewed imaging q3months. ORR/DCR and PFS/OS were compared between patients with and without liver metastases with the Fisher's exact and log-rank tests, respectively. P-values are two-sided.

RESULTS

We treated 57 patients (median age 57 years [range, 26-85], 61% male, 88% white, 65% with liver metastases) from 07/2017 to 05/2022. Patients received a median of 3 (range, 1-10) prior lines of systemic therapy. The combined ORR was 14% (8/57; 95% CI, 6-26%) and DCR was 35% (20/57; 95% CI, 23-49%). The ORR was 30% (6/20; 95% CI, 12-54%) in patients without liver metastases and 5% (2/37; 95% CI, 1-18%) in patients with liver metastases (p = 0.017). The DCR was 55% (11/20; 95% CI, 32-77%) in patients without liver metastases and 24% (9/37; 94% CI, 12-41%) in patients with liver metastases (p = 0.040). 76% (28/37) of patients with liver metastases received liver-directed RT including 2/2 (100%) patients with a PR. The ORR was 0% in patients with liver metastases without liver-directed RT. The median PFS was 1.8 months (95% CI, 1.2-2.4 months) and OS was 9.8 months (95% CI, 6.8-12.8). OS was longer in patients without liver metastases (median 13.6 v 6.8 months, p = 0.010) and in patients treated with liver-directed RT among those with liver metastases (median 7.5 months v 4.5 months, p = 0.025).

CONCLUSION

Among patients with metastatic MSS CRC treated with ICIs and RT in two phase 2 studies, ORR, DCR, and OS are significantly higher in patients without liver metastases. Liver-directed RT may improve ICI efficacy and OS in patients with liver metastases. Further analysis of PFS and prospective study of ICIs with comprehensive liver-directed RT are warranted.

Prospective Validation of Single Nucleotide Polymorphisms as Predictors of Gastrointestinal, Genitourinary, and Sexual Patient-Reported Outcomes Following Radiotherapy for Prostate Cancer

PURPOSE/OBJECTIVE(S)

Radiotherapy (RT) for localized prostate cancer (PC) can adversely impact gastrointestinal (GI), genitourinary (GU), and sexual quality of life (QoL). Biomarkers are needed to accurately predict individualized risk of toxicity and enable tailoring of therapy. Single nucleotide polymorphisms (SNPs) have been reported as potential predictors of RT-related toxicities, but have not been associated with patient-report outcomes (PRO) in prospective cohorts. In this study, we sought to validate these SNPs in a prospective registry study of RT for PC, with high-quality prospectively collected PRO data.

MATERIALS/METHODS

Men with low/intermediate risk PC were consented to a multicenter companion registry study associated with the PARTIQoL Phase III Randomized Trial of proton vs. photon RT. Patients received RT to prostate/seminal vesicles per protocol. Androgen deprivation therapy and pelvic lymph node RT were not allowed. 95 patients enrolled between 2014-2020 at a single institution had blood specimens available for germline DNA analysis. 172 SNPs previously reported to correlate with GI, GU, and/or sexual RT toxicities were genotyped. PRO data through the Expanded Prostate Cancer Index Composite (EPIC) were collected prior to RT and at prespecified follow-up (FU) time points. Change of the EPIC score from baseline was compared between genotypes of previously identified SNPs using a two-sample t-test. Significant clinically meaningful QoL differences were identified by an effect size of at least 0.4σ with two-sided p<0.05, where σ represents the standard deviation of the score change.

RESULTS

Median FU was 39 months (r, 6-89). Median age was 68 years (r, 52-83). Features at diagnosis include: 77% T1c, median PSA 5.8 (r, 1.43-15.1), 53% Gleason 7, median prostate volume 45.5cc (r, 16-142). 43% received proton RT; 53% had a rectal spacer. 40% received 79.2 Gy/44 fractions; 60% received 70 Gy/28 fractions. Between 6 to 24 months post-RT, there were 19 SNPs that were significantly associated with clinically meaningful decreases in GI QoL scores, 19 that were significantly associated with clinically meaningful decreases in GU QoL scores, and 10 SNPs that were significantly associated with clinically meaningful decreases in sexual QoL scores. Three BRCA2 SNPs (rs1801439, rs1801499, rs1799944) were significantly associated with clinically meaningful decreases in both GI and GU QoL scores.

CONCLUSION

Of the 172 SNPs previously reported to be associated with GI, GU, and/or sexual toxicity after prostate RT, 23% were validated for domain-specific QoL detriment. Ongoing analyses include integrated modeling of dosimetry and SNP data for prediction of toxicities and PRO, and evaluation of potential interactions between RT modality (proton/photon) and QoL-associated SNPs.

Extrathoracic Metastases in Pleural Mesothelioma

Introduction

Guidelines recommend obtaining a computed tomography scan of the chest for the staging of pleural mesothelioma and for assessing response to treatment. Consensus is lacking regarding the necessity of serial imaging of distant extrathoracic sites. In this study, we determined the prevalence of extrathoracic metastases in patients with pleural mesothelioma.

Methods

We conducted a retrospective review of patients with pleural mesothelioma treated at Massachusetts General Hospital between 1999 and 2022 who were referred for extrathoracic imaging during their disease course. Imaging reports were reviewed to determine sites of metastasis and calculate the time to development of extrathoracic metastasis. Overall survival and prevalence of extrathoracic metastasis were compared for patients with epithelioid versus nonepithelioid mesothelioma.

Results

The study included 148 patients, 69 (47%) of whom had undergone cytoreductive surgery. Histologic types included epithelioid (n = 82, 55%), biphasic (n = 49, 33%), and sarcomatoid (n = 10, 7%) mesothelioma. The median overall survival for the cohort was 24.0 months, specifically 34.7 months and 16.7 months for patients with epithelioid and nonepithelioid tumors, respectively (p < 0.001). There were 65 (44%) patients who developed extrathoracic metastases, with a median time to extrathoracic metastasis of 11.5 months. The most common sites of involvement were extrathoracic nodes (22%), peritoneum (20%), bone (11%), and liver (11%). Of the 76 patients referred for brain imaging, seven (9%) had brain metastases. The frequency of extrathoracic metastasis was identical for epithelioid and nonepithelioid mesothelioma (44%). Overall survival was shorter for patients who developed extrathoracic metastases (hazard ratio 5.9, p < 0.001).

Conclusions

Patients with pleural mesothelioma often develop extrathoracic metastases, providing a rationale for routinely obtaining imaging that encompasses sites outside of the thoracic cavity.

Therapy-induced APOBEC3A drives evolution of persistent cancer cells

Acquired drug resistance to anticancer targeted therapies remains an unsolved clinical problem. Although many drivers of acquired drug resistance have been identified1-4, the underlying molecular mechanisms shaping tumour evolution during treatment are incompletely understood. Genomic profiling of patient tumours has implicated apolipoprotein B messenger RNA editing catalytic polypeptide-like (APOBEC) cytidine deaminases in tumour evolution; however, their role during therapy and the development of acquired drug resistance is undefined. Here we report that lung cancer targeted therapies commonly used in the clinic can induce cytidine deaminase APOBEC3A (A3A), leading to sustained mutagenesis in drug-tolerant cancer cells persisting during therapy. Therapy-induced A3A promotes the formation of double-strand DNA breaks, increasing genomic instability in drug-tolerant persisters. Deletion of A3A reduces APOBEC mutations and structural variations in persister cells and delays the development of drug resistance. APOBEC mutational signatures are enriched in tumours from patients with lung cancer who progressed after extended responses to targeted therapies. This study shows that induction of A3A in response to targeted therapies drives evolution of drug-tolerant persister cells, suggesting that suppression of A3A expression or activity may represent a potential therapeutic strategy in the prevention or delay of acquired resistance to lung cancer targeted therapy.

Health-related quality of life analyses in nonfunctioning pituitary macroadenoma patients identifies at-risk populations

PURPOSE

The quality of life (QoL) impact of multidisciplinary treatment for patients with nonfunctioning pituitary macroadenomas (NFPMA) is unclear. We sought to investigate associations between patient factors, clinical data, and patient-reported QoL in patients with NFPMA.

METHODS

Patients with treated NFPMA and > 1 year of follow up after transsphenoidal surgery (TSS) and with no evidence of progressive disease were evaluated utilizing the following patient-reported outcome measures: RAND-36-Item Health Survey, Multidimensional Fatigue Inventory, Cognitive Failures Questionnaire.

RESULTS

229 eligible patients completed QoL questionnaires a median of 7.7 years after initial transsphenoidal surgery (TSS). 25% of participants received radiation therapy (RT) a median of 2.0 years (0.1-22.5) after initial TSS. Patients who received RT were younger (median age 46 v 58, p < 0.0001), had larger tumors (28 mm v 22 mm, p < 0.0001), were more likely to have visual symptoms (65% v 34%, p = 0.0002), and were more likely to have hypopituitarism (93% v 62%, p < 0.0001). Patients with hypopituitarism reported worse energy and fatigue and cognitive function (p < 0.03). Patients who received RT reported significantly worse general health, physical health, physical fatigue and cognitive functioning (p < 0.05). The largest QoL differences were in patients who experienced a financial stressor, independent of treatment type.

CONCLUSION

Hypopituitarism, radiation therapy after TSS, and financial stressors are associated with more impaired QoL in patients with NFPMA. Awareness of these factors can better guide use and timing of radiation therapy in addition to identifying patients who can benefit from multidisciplinary surveillance.

Patterns of failure in pediatric medulloblastoma and implications for hippocampal sparing

BACKGROUND

Hippocampal avoidance (HA) has been shown to preserve cognitive function in adult patients with cancer treated with whole-brain radiation therapy for brain metastases. However, the feasibility of HA in pediatric patients with brain tumors has not been explored because of concerns of increased risk of relapse in the peri-hippocampal region. Our aim was to determine patterns of recurrence and incidence of peri-hippocampal relapse in pediatric patients with medulloblastoma (MB).

METHODS AND MATERIALS

We identified pediatric patients with MB treated with protons between 2002 and 2016 and who had recurrent disease. To estimate the risk of peri-hippocampal recurrence, three hippocampal zones (HZs) were delineated corresponding to ≤5 mm (HZ-1), 6 to 10 mm (HZ-2), and >10 mm (HZ-3) distance of the recurrence from the contoured hippocampi. To determine the feasibility of HA, three standard-risk patients with MB were planned using either volumetric-modulated arc therapy (VMAT) or intensity-modulated proton therapy (IMPT) plans.

RESULTS

Thirty-eight patients developed a recurrence at a median of 1.6 years. Of the 25 patients who had magnetic resonance imaging of the recurrence, no patients failed within the hippocampus and only two patients failed within HZ-1. The crude incidence of peri-hippocampal failure was 8%. Both HA-VMAT and HA-IMPT plans were associated with significantly reduced mean dose to the hippocampi (p < .05). HA-VMAT and HA-IMPT plans were associated with decreased percentage of the third and lateral ventricles receiving the prescription craniospinal dose of 23.4 Gy.

CONCLUSIONS

Peri-hippocampal failures are uncommon in pediatric patients with MB. Hippocampal avoidance should be evaluated in a prospective cohort of pediatric patients with MB.

PLAIN LANGUAGE SUMMARY

In this study, the patterns of disease recurrence in patients with a pediatric brain tumor known as medulloblastoma treated with proton radiotherapy were examined. The majority of failures occur outside of an important structure related to memory formation called the hippocampus. Hippocampal sparing radiation plans using proton radiotherapy were generated and showed that dose to the hippocampus was able to be significantly reduced. The study provides the rationale to explore hippocampal sparing in pediatric medulloblastoma in a prospective clinical trial.

Recent trends of "manels": gender representation among invited panelists at an international oncology conference

BACKGROUND

Gender disparities in academic medicine are a long-acknowledged concern, particularly at medical conferences. We investigated gender representation and prevalence of "manels" (all-men panels) among invited speakers at the 2018-2021 American Society of Clinical Oncology Annual Meetings.

METHODS

Using American Society of Clinical Oncology online programs, 2018-2021 faculty information was obtained, including perceived or self-reported gender, medical specialty, session type, and topic. Primary outcomes were percentage of manels and proportion of women panelists over time; women representation among specialties and topics were evaluated. Cochran-Armitage and Fisher's exact tests were used to analyze trends in proportion of manels and women representation over time and to compare each session type, topic, or specialty with other categories combined, respectively.

RESULTS

During 2018-2021, there were 670 sessions, 81 of which (12.1%) were manels. Among 2475 panelists, 1181 (47.7%) were women. Over time, the percentage of manels significantly decreased from 17.4% in 2018 to 9.9% in 2021 (P = .030). The highest proportion of manels was observed for leadership or special sessions (17.1%, P = .419). Women panelists were underrepresented for the topics of genitourinary cancers (38.6%, P = .029) and translational or preclinical sciences (36.7%, P < .001). There was a positive trend toward improved women representation among translational or preclinical sciences (27.4% in 2018 vs 41.8% in 2021, P = .031) but not among genitourinary cancers (41.1% in 2018 vs 40.7% in 2021, P = .969).

CONCLUSIONS

The number of women panelists increased during the study period, with a corresponding decrease in the proportion of manels, specifically in education and leadership or special sessions. Ongoing underrepresentation of women in genitourinary cancers and translational or preclinical topics underscores the importance of annual meeting organizers continuing to strive for diverse gender representation.

Prospective validation of single nucleotide polymorphisms as predictors of gastrointestinal, genitourinary, and sexual toxicities following radiation therapy for prostate cancer

385

Background: Radiation therapy (RT) for localized prostate cancer (PC) may result in long-term gastrointestinal (GI), genitourinary (GU), and sexual toxicities that adversely impact quality of life. Biomarkers are needed to accurately predict individualized RT toxicity risk and enable tailoring of treatment. Single nucleotide polymorphisms (SNPs) have been reported as predictors of RT-related toxicities, but have not been independently validated in prospective, prostate-specific cohorts. In this study, we sought to validate these SNPs in a prospective registry study of RT for PC, with high-quality prospectively collected toxicity data. Methods: Men with low/intermediate risk PC were consented to a multicenter companion registry study associated with the PARTIQoL Phase III Randomized Trial of proton vs. photon RT. Patients received RT to prostate/seminal vesicles per protocol. Androgen deprivation therapy/pelvic lymph node RT were not allowed. 95 patients enrolled between 2014-2020 at a single institution had whole blood specimens available for analysis. 172 SNPs previously reported to correlate with GI, GU, and/or sexual RT toxicities were genotyped. CTCAEv4 physician-reported toxicity was collected at prespecified follow-up (FU) time points. Association of previously identified SNP genotypes with the worst toxicity grade was analyzed using two-sided Fisher’s exact test. Results: Median FU was 39 months (r, 6-89). Median age was 68 years (r, 52-83). Features at diagnosis include: 77% T1c, median PSA 5.8 (r, 1.43-15.1), 53% Gleason 7, median prostate volume 45.5cc (r, 16-142). 43% received proton RT; 53% had a rectal spacer. 40% received 79.2 Gy/44 fractions; 60% received 70 Gy/28 fractions. By 24 months post-RT, 21 (22%) patients experienced grade 1-2 Gl toxicity, 33 (35%) experienced grade 1-2 GU toxicity, and 68 (72%) experienced grade 1-3 sexual toxicity. Of the 172 SNPs examined, significant associations were detected for rs1805794 with a higher incidence of grade 1-2 late GI toxicity (P=0.006), rs1800872 with a higher incidence of grade 1-2 late GU effects (P=0.005) and rs25489 with a higher incidence of grade 1-3 sexual dysfunction (P=0.003). rs3749191, rs4073, rs2243250, and rs7356945 were significantly associated with grade 2 late GU toxicity (all P≤0.008). Significant associations were also observed between other SNPs and late toxicity: 4 SNPs GI, 9 SNPs GU, 7 SNPs sexual (all 0.01≤P≤0.05). Conclusions: Of the 172 SNPs previously reported to be associated with GI, GU, and/or sexual toxicity after prostate RT, 16% were validated by conventional statistical criteria. Ongoing analyses include integrated modeling of dosimetry and SNP data for prediction of toxicities and PROs, and evaluation of potential interactions between RT modality (proton/photon) and toxicity-associated SNPs.

A multicenter, randomized phase II study of total neoadjuvant therapy (TNT) with FOLFIRINOX (FFX) and SBRT, with or without losartan (L) and nivolumab (N) in borderline resectable (BR) and locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC)

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Background: Outcomes in BR and LA PDAC remain historically poor, in part due to low rates of R0 resection. A prior phase II study demonstrated that losartan (L) as a TGF-beta inhibitor combined with FOLFIRINOX (FFX) and radiation in LA PDAC led to a 61% R0 resection rate. Additionally, prior phase II studies suggest potential synergy with SBRT and nivolumab (N) in PDAC. We conducted a multi-center, randomized phase II trial to evaluate the effect of L and L+N in combination with TNT using FFX and SBRT. Methods: Patients with BR or LA PDAC by NCCN criteria, pathologically confirmed, ACE/ARB naïve, were randomized to TNT with FFX and SBRT (Arm 1), TNT + L (Arm 2), and TNT+L+N (Arm 3), stratified by BR/LA. Patients already on an ACE or ARB were enrolled on an exploratory arm of TNT+N (Arm 4) and will be reported separately. TNT consisted of FFX x 8 followed by SBRT (6.6 Gy x 5). L was given at 50 mg qd throughout TNT and for 6 mo after surgery. N was given at 240 mg flat dosing q2 wks concurrent with SBRT and for 12 doses postoperatively. All patients were recommended for surgical exploration after TNT. The study was designed to compare the R0 resection rate on each of Arms 2 and 3 independently versus Arm 1 at a one-sided 0.10 level. Secondary endpoints were PFS, OS, and pCR rates and analyzed using two-sided tests with Arm 1 as the control arm. Intent-to-treat analysis was based on eligible patients who started therapy on protocol. Results: Patients with BR or LA PDAC by NCCN criteria, pathologically confirmed, ACE/ARB naïve, were randomized to TNT with FFX and SBRT (Arm 1), TNT + L (Arm 2), and TNT+L+N (Arm 3), stratified by BR/LA. Patients already on an ACE or ARB were enrolled on an exploratory arm of TNT+N (Arm 4) and will be reported separately. TNT consisted of FFX x 8 followed by SBRT (6.6 Gy x 5). L was given at 50 mg qd throughout TNT and for 6 mo after surgery. N was given at 240 mg flat dosing q2 wks concurrent with SBRT and for 12 doses postoperatively. All patients were recommended for surgical exploration after TNT. The study was designed to compare the R0 resection rate on each of Arms 2 and 3 independently versus Arm 1 at a one-sided 0.10 level. Secondary endpoints were PFS, OS, and pCR rates and analyzed using two-sided tests with Arm 1 as the control arm. Intent-to-treat analysis was based on eligible patients who started therapy on protocol. Conclusions: We did not observe effects of L and L+N on the R0 resection rate, PFS, OS, and pCR rate when added to TNT with FFX and SBRT for BR or LA PDAC. The lack of differences may reflect heterogeneity in surgical opinion as the decision for proceeding to surgery following TNT tends to be highly variable in a population with historically low resection rates. Clinical trial information: NCT03563248 .

Factors Associated With Developing Neurocognitive Adverse Events in Patients Receiving Lorlatinib After Progression on Other Targeted Therapies

INTRODUCTION

The safety profile of lorlatinib includes neurocognitive adverse events (NAEs). Baseline factors associated with developing NAEs remain poorly characterized.

METHODS

Records from patients who received lorlatinib through prospective studies at Massachusetts General Hospital (MGH, n = 124) or the phase 1/2 B7461001 (NCT01970865; n = 248) study were reviewed to identify potential associations between comorbidities, baseline medications, and NAEs.

RESULTS

Most patients experienced a NAE (MGH: 60%, B7461001: 49%). Cognitive effects occurred in 40% and 29% of patients in the MGH and B7461001 cohorts, respectively. Brain metastases (p = 0.008), brain radiation (p = 0.033), psychiatric illness (p = 0.008), psychiatric medications (p < 0.001), antiepileptics (p < 0.001), and stimulants (p = 0.026) were associated with developing cognitive effects in B7461001. Mood effects occurred in 36% and 23% of patients in the MGH and B7461001 cohorts, respectively. In the MGH cohort, psychiatric illness (p = 0.02) and stimulants (p = 0.01) were associated with developing mood effects whereas brain surgery (p = 0.020), psychiatric medications (p < 0.001), benzodiazepines (p = 0.002), and sedatives (p = 0.034) were associated with developing mood effects in B7461001. Psychotic effects were infrequent (MGH: 3%, B7461001: 9%) and were associated with brain surgery in the MGH cohort (p = 0.001) and age in B7461001 (p = 0.014). Speech effects were observed in 23% and 11% of patients in the MGH and B7461001 cohorts, respectively. Brain radiation (p = 0.012) and antiepileptics (p < 0.001) were associated with speech effects in B7461001. Dose reductions were implemented for 52% and 18% of patients with NAEs in MGH and B7461001 cohorts, respectively, with mitigating effect.

CONCLUSIONS

Neurocognitive effects from lorlatinib are common. Lorlatinib-related NAEs may be influenced by multiple factors, including brain metastases, brain radiation, psychiatric illness, and use of neurotropic medications.

Recent trends of “manels” and gender representation among panelists at the ASCO annual meeting

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Background: Gender disparities in academic medicine are a long-acknowledged concern. Efforts to recognize this imbalance and increase inclusivity continue, particularly in academic medical conferences. In June 2019, NIH Director Francis S. Collins MD, PhD publicly called for an end to all-male speaking panels (“manels”). It is unclear whether academic oncology conferences followed suit. We investigated the prevalence and longitudinal trends of manels and gender representation at the ASCO Annual Meeting during 2018-2021. Methods: Using ASCO online programs, 2018-2021 faculty information was obtained. Data collected included perceived or self-reported gender, medical specialty, panel role (chair vs. non-chair), type of session, and topic. Primary outcomes included percentage of manels and proportion of female panelists over time. Female representation among chairs, specialties, and topics were evaluated. Cochran-Armitage test was used to analyze time trends in the proportion of manels and female representation. Fisher’s exact test was used to compare each session type, topic, or specialty to other categories combined. P-values are based on a two-sided hypothesis. Results: During 2018-2021, there were 670 sessions total, 81 of which (12.1%) were manels. Among 2,475 faculty members, 1,181 (47.7%) were females. Over time, there was a significant decrease in the number of manels, from 17.4% in 2018 to 9.9% in 2021 (p = 0.030) and a corresponding increase in proportion of female panelists from 41.6% to 54.0% (p < 0.001). The largest decrease in manels occurred between 2018 (17.4%) and 2019 (10.5%). Among session type and topic, the highest proportion of manels was observed for leadership/special sessions (17.1%, p = 0.419) and translational/pre-clinical topics (19.6%, p = 0.024), respectively. The chair role was majority male (53.2%) in 2018 but increased to > 50% female representation in 2019-2021 (p = 0.157). The lowest proportion of female panelists were in pathology/radiology/dermatology specialties (combined 26.2%, p = 0.001). Female panelists were underrepresented for the topics of genitourinary cancers (38.6%, p = 0.029) and translational/pre-clinical sciences (36.7%, p < 0.001). Females were overrepresented in the topic of supportive oncology (70.3%, p < 0.001). There was a positive trend toward improved female representation among translational/pre-clinical sciences (27.4% in 2018 to 41.8% in 2021, p = 0.031), but with little improvement among genitourinary cancers (41.1% in 2018 to 40.7% in 2021, p = 0.969). Conclusions: The number of female ASCO panelists increased during the study period and surpassed 50% in 2021, with a corresponding decrease in the proportion of manels. Still, there are certain topics/specialties where female representation has remained stagnant. ASCO Annual Meeting organizers should continue to strive for diverse gender representation and the elimination of manels.

Phase I/II investigator-initiated study of olaparib and temozolomide in SCLC: Updated analysis and CNS outcomes

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Background: Temozolomide has activity in small-cell lung cancer (SCLC), including patients (pts) with brain metastases (mets; Pietanza M, Clin Cancer Res 2012). Inhibition of Poly (ADP-ribose) polymerase (PARP) is another therapeutic strategy in SCLC. We hypothesized that olaparib plus temozolomide may be safe and effective for pts with relapsed SCLC and clinically active against CNS disease (Farago A, Cancer Discovery 2019). Here, we present an updated analysis of this combination in pts with relapsed SCLC, including a second cohort testing an alternative dosing strategy and an exploratory analysis of CNS-specific outcomes. Methods: In this phase I/II trial of olaparib plus temozolomide in pts with recurrent SCLC, pts were sequentially enrolled into two cohorts defined by dosing schedule. In cohort 1, olaparib was dosed on D1-7 of each 21d cycle. In cohort 2, olaparib was dosed on D1-21. Temozolomide was dosed on D1-7 in both cohorts. Each cohort had a phase I portion (conventional 3+3 dose-escalation) for determination of MTD and RP2D and a phase II portion with primary endpoint of ORR. Per protocol, eligible pts could have untreated asymptomatic brain mets < 1cm and, after mandatory baseline imaging, CNS imaging was performed at investigator’s discretion. A post-hoc exploratory analysis of CNS-specific outcomes was performed using modified RECIST criteria (Long GV, Lancet Oncol 2012) in which brain mets ≥5mm were considered measurable, and intracranial response was independently assessed by an attending radiologist. Results: 66 pts with median of 2 prior lines of therapy (range, 1-7) were enrolled, 50 pts in cohort 1 and 16 pts in cohort 2. 33/66 (50%) pts had history of brain mets, 15/66 (23%) pts had untreated brain mets at enrollment. The confirmed ORR of cohort 2 was 7% (1/14 evaluable pts, 95% CI: 0.2-33.9%), and the updated confirmed ORR of the entire study population was 34% (21/62 evaluable pts, 95% CI: 22.3-47.0%). The most common adverse events were hematologic toxicities (thrombocytopenia, anemia, and neutropenia). 22/50 (44%) of cohort 1 pts and 4/16 (25%) of cohort 2 pts required dose reduction. Of 15 pts with untreated brain mets, best overall intracranial response (including both confirmed and unconfirmed responses) was CR in 6 pts, PR in 4 pts, SD in 3 pts and PD in 1 for a CNS disease control rate of 87% (95% CI: 59.5-98.3%). Of 10 pts with CR/PR as their best intracranial response, 4 responses were confirmed. With non-CNS progression as a competing risk, the probability of CNS progression among the entire study population was 17% (95% CI: 8.8-26.7%) at 6 months and 21% (95% CI: 12.1-32.0%) at 12 months. Conclusions: Olaparib and temozolomide may be an effective therapy for relapsed SCLC, especially for pts with CNS disease where we observed a high rate of intracranial disease control. Ongoing analyses regarding optimal dosing schedule will inform potential for future use of this combination. Clinical trial information: NCT02446704.

Fractionated Proton Radiation Therapy and Hearing Preservation for Vestibular Schwannoma: Preliminary Analysis of a Prospective Phase 2 Clinical Trial

BACKGROUND

Local management for vestibular schwannoma (VS) is associated with excellent local control with focus on preserving long-term serviceable hearing. Fractionated proton radiation therapy (FPRT) may be associated with greater hearing preservation because of unique dosimetric properties of proton radiotherapy.

OBJECTIVE

To investigate hearing preservation rates of FPRT in adults with VS and secondarily assess local control and treatment-related toxicity.

METHODS

A prospective, single-arm, phase 2 clinical trial was conducted of patients with VS from 2010 to 2019. All patients had serviceable hearing at baseline and received FPRT to a total dose of 50.4 to 54 Gy relative biological effectiveness (RBE) over 28 to 30 fractions. Serviceable hearing preservation was defined as a Gardner-Robertson score of 1 to 2, measured by a pure tone average (PTA) of ≤50 dB and a word recognition score (WRS) of ≥50%.

RESULTS

Twenty patients had a median follow-up of 4.0 years (range 1.0-5.0 years). Local control at 4 years was 100%. Serviceable hearing preservation at 1 year was 53% (95% CI 29%-76%), and primary end point was not yet reached. Median PTA and median WRS both worsened 1 year after FPRT (P < .0001). WRS plateaued after 6 months, whereas PTA continued to worsen up to 1 year after FPRT. Median cochlea D90 was lower in patients with serviceable hearing at 1 year (40.6 Gy [RBE] vs 46.9 Gy [RBE]), trending toward Wilcoxon rank-sum test statistical significance (P = .0863). Treatment was well-tolerated, with one grade 1 cranial nerve V dysfunction and no grade 2+ cranial nerve dysfunction.

CONCLUSION

FPRT for VS did not meet the goal of serviceable hearing preservation. Higher cochlea doses trended to worsening hearing preservation, suggesting that dose to cochlea correlates with hearing preservation independent of treatment modality.

Longitudinal trends of "manels" and gender representation at the ASCO Genitourinary Cancers Symposium

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Background: Gender disparity in academic medicine has been a longstanding issue. Efforts have been made to recognize this imbalance and increase inclusivity. Despite this, a recent study examining the prevalence of all-male panels (“manels”) found that female faculty are significantly underrepresented at urology meetings, and nearly two-thirds of the sessions were manels. Therefore, we aimed to investigate the prevalence and longitudinal trends of manels and gender representation across genitourinary oncology disciplines at the ASCO Genitourinary Cancers Symposium (GU ASCO). Methods: GU ASCO online programs from 2018-2021 were used to obtain faculty information. Data collected included perceived gender, medical specialty, and panel role (chair/moderator vs. non-chair/non-moderator). For year 2021, additional data about the panelists, including the number of publications, H-index, citations, and academic rank, was collected. The primary outcomes were the percentage of manels and proportion of female panelists over time. Additionally, female representation among chair/moderators and specialties were evaluated. Results: Among 83 sessions involving 317 faculty members, 227 (71.6%) were males (p<0.001), and 28 panel sessions (33.7%) were manels. Between 2018 and 2020, there was a decrease in the prevalence of manels from 45% to 21.7%, but in 2021, it rose to 32.0%. The proportion of female panel members increased over time from 17.1% in 2018 to 35.7% in 2021 (p=0.012). The role of chair/moderator was predominantly represented by males (67.2%, p<0.001). The proportion of male panelists was particularly high in urology (91.2%, p<0.001) and radiation oncology (81.8%, p=0.002) compared to medical oncology (54.6%). In 2021, male speakers held higher academic rank (i.e. professor, associate, assistant) (p=0.020) and had a greater number of publications (p=0.003), H-index (p=0.009), citations (p=0.014) than females (Table). Conclusions: Over time, the number of female panelists increased with a corresponding decrease in proportion of manels, with the exception of 2021. Future studies that include data on meeting participant demographics will provide insight on whether panelists are over/under-represented in proportion to the audience. While improvements in male and female representation have been made over the years, meeting organizers should strive for representation that reflects a diversity of expertise and perspectives. [Table: see text]

A phase II study of niraparib and dostarlimab with radiation in patients with metastatic pancreatic cancer

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Background: PARP inhibitors have activity as monotherapy in BRCA1/2 mutated metastatic pancreatic cancer; however, several other genes and associated proteins exist in the homologous recombination repair (HRR) pathway promoting resistance to chemotherapy and radiation-induced damage. Tumors with HRR deficiency have an impaired ability to repair themselves and are susceptible to PARP inhibition, but ionizing radiation can also induce DNA breaks. Ongoing research suggests that PARP inhibitors may cause radio-sensitization and may also enhance sensitivity to immunotherapy. We conducted a phase 2 study of niraparib and dostarlimab with radiation in a biomarker unselected PDAC population given PARP inhibitors' immunomodulatory and radiosensitizing effects. Methods: In this open-label, single-arm, phase-2 study, eligible patients had histologically confirmed MSS PDAC, ECOG PS 0-1, and progressed on at least one line of jm. Treatment consisted of niraparib 200 mg daily on a 21-day cycle, dostarlimab 500 mg every 3 weeks every 4 weeks for the first four doses, then 1000 mg every 6 weeks, and 3 fractions of 8 Gy at Cycle 2. Treatment continued until progressive disease, discontinuation, or withdrawal. The primary endpoint was DCR by RECIST 1.1 with radiological evaluations every 3 months. Secondary endpoints included DCR by irRECIST, PFS, OS, and safety. Responses were defined as disease control outside the radiation field. We obtained serial tumor biopsies, including pre-treatment. A two-stage design was used, requiring disease control in at least one of the first 15 patients before proceeding to the full accrual of 25 patients. Intention to treat analysis included all patients receiving at least one dose of any study agent. Results: We enrolled and treated 15 pts (median age 60 years [range 37-77], 53% male) from 08/2020 to 05/2021. Overall, DCR was 0/15 (95% CI: 0-22%), median PFS was 1.6 months (95% CI: 1.1-2.7), and median OS 3.1 months (95% CI: 1.5-7.7). Among 27 treatment-related serious adverse events, 15 (56%) were grade 3, including decreased CD4 lymphocytes, thrombocytopenia, anemia, and fatigue being the most common. Conclusions: The combination of niraparib and dostarlimab with radiation did not meet the pre-specified criteria for expansion to full accrual. Further analyses of dose intensity in this heavily pretreated and evaluation of in-field responses are underway. Further investigation of the combination with biomarker selection is warranted. Clinical trial information: NCT04409002.

Decade Long Disease, Secondary Malignancy, and Brainstem Injury Outcomes in Pediatric and Young Adult Medulloblastoma Patients Treated with Proton Radiotherapy

BACKGROUND

Survivors of pediatric medulloblastoma experience long term morbidity associated with the toxic effects of post-operative radiotherapy. Proton radiotherapy limits radiation dose to normal tissues thereby reducing side effects of treatment while maintaining high cure rates. However, long term data on disease outcomes and long-term effects of proton radiotherapy remain limited.

METHODS

178 Pediatric medulloblastoma patients treated with proton radiotherapy between 2002-2016 at the Massachusetts General Hospital comprise the cohort of patients who were treated with surgery, radiation therapy and chemotherapy. We evaluated EFS, OS, and LC using the Kaplan Meier method. The cumulative incidence of brainstem injury and secondary malignancies was assessed.

RESULTS

Median follow-up was 9.3 years. 159 patients (89.3%) underwent a gross total resection (GTR). The 10-year OS for the entire cohort, standard risk, and intermediate/high risk patients was 79.3%, 86.9%, and 68.9% respectively. The 10-year EFS for entire cohort, SR, and IR/HR cohorts was 73.8%, 79.5%, and 66.2%. The 10-year EFS and OS for patients with GTR/NTR were 75.3% and 81.0% versus 57.7% and 61.0% for STR. On univariate analysis, IR/HR status was associated with inferior EFS, while both anaplastic histology and IR/HR status was associated with worse overall survival. The 10-year cumulative incidence of secondary tumors and brainstem injury was 5.6% and 2.1%, respectively.

CONCLUSIONS

In this cohort study of pediatric medulloblastoma, proton radiotherapy was effective and disease outcomes were comparable to historically treated photon cohorts. The incidence of secondary malignancies and brainstem injury was low in this cohort with mature follow up.

Radiation therapy enhances immunotherapy response in microsatellite stable colorectal and pancreatic adenocarcinoma in a phase II trial

Overcoming intrinsic resistance to immune checkpoint blockade for microsatellite stable (MSS) colorectal cancer (CRC) and pancreatic ductal adenocarcinoma (PDAC) remains challenging. We conducted a single-arm, non-randomized, phase II trial (NCT03104439) combining radiation, ipilimumab and nivolumab to treat patients with metastatic MSS CRC (n = 40) and PDAC (n = 25) with an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. The primary endpoint was disease control rate (DCR) by intention to treat. DCRs were 25% for CRC (ten of 40; 95% confidence interval (CI), 13-41%) and 20% for PDAC (five of 25; 95% CI, 7-41%). In the per-protocol analysis, defined as receipt of radiation, DCR was 37% (ten of 27; 95% CI, 19-58%) in CRC and 29% (five of 17; 95% CI, 10-56%) in PDAC. Pretreatment biopsies revealed low tumor mutational burden for all samples but higher numbers of natural killer (NK) cells and expression of the HERVK repeat RNA in patients with disease control. This study provides proof of concept of combining radiation with immune checkpoint blockade in immunotherapy-resistant cancers.

Phase II trial of veliparib and temozolomide in metastatic breast cancer patients with and without BRCA1/2 mutations

PURPOSE

We evaluated the efficacy and safety of poly-(adenosine diphosphate-ribose) polymerase (PARP) 1 and 2 inhibitor veliparib and temozolomide in metastatic breast cancer patients with and without germline BRCA1/2 mutations.

METHODS

In this single-arm phase II trial, patients with metastatic breast cancer received veliparib 30 to 40 mg twice daily on days 1 to 7 with concurrent temozolomide 150 mg/m² on days 1 to 5 of a 28-day cycle. The primary cohort was unselected for BRCA mutation status, and an expansion cohort enrolled only BRCA1/2 carriers. The primary endpoint was objective response rate (ORR) in each cohort. Secondary endpoints included progression-free survival (PFS), clinical benefit rate (CBR), and evaluation of safety and tolerability.

RESULTS

In the primary cohort of 41 unselected patients, which included 9 BRCA mutation carriers, the ORR was 10% and clinical benefit rate at 4 months (CBR) was 27%. In the expansion cohort of 21 BRCA1/2 carriers, the ORR was 14% and CBR was 43%. Among all 30 BRCA1/2 carriers, the ORR was 23% versus 0% among non-carriers. In the subset of BRCA1/2 carriers, the ORR was 32% among platinum-naïve patients versus 9% among platinum-exposed patients. The median PFS was 3.3 months among BRCA1/2 carriers compared to 1.8 months among non-carriers (HR: 0.48, p = 0.006). A longer median PFS of 6.2 months was observed among BRCA1/2 carriers who had no prior platinum therapy. The most common grade 3 and 4 toxicities were thrombocytopenia (32%) and neutropenia (21%) that generally improved with dose modifications.

CONCLUSION

Veliparib and temozolomide demonstrated clinical activity in platinum-naïve BRCA-associated metastatic breast cancer with manageable toxicity at doses of veliparib well below the single-agent active dose. Although the study did not meet its primary endpoint in unselected nor BRCA-associated breast cancer, this regimen was further evaluated in the BROCADE 2 study.

TRIAL REGISTRATION

NCT01009788 (ClinicalTrials.gov), November 9, 2009.

Screening and Validation of Molecular Targeted Radiosensitizers

The development of molecular targeted drugs with radiation and chemotherapy are critically important for improving the outcomes of patients with hard-to-treat, potentially curable cancers. However, too many preclinical studies have not translated into successful radiation oncology trials. Major contributing factors to this insufficiency include poor reproducibility of preclinical data, inadequate preclinical modeling of inter-tumoral genomic heterogeneity that influences treatment sensitivity in the clinic, and a reliance on tumor growth delay instead of local control (TCD50) endpoints. There exists an urgent need to overcome these barriers to facilitate successful clinical translation of targeted radiosensitizers. To this end, we have employed 3D cell culture assays to better model tumor behavior in vivo. Examples of successful prediction of in vivo effects with these 3D assays include radiosensitization of head and neck cancers by inhibiting epidermal growth factor receptor or focal adhesion kinase signaling, and radioresistance associated with oncogenic mutation of KRAS. To address the issue of tumor heterogeneity we leveraged institutional resources that allow high-throughput 3D screening of radiation combinations with small molecule inhibitors across genomically characterized cell lines from lung, head and neck, and pancreatic cancers. This high-throughput screen is expected to uncover genomic biomarkers that will inform the successful clinical translation of targeted agents from the NCI CTEP portfolio and other sources. Screening "hits" need to be subjected to refinement studies that include clonogenic assays, addition of disease-specific chemotherapeutics, target/biomarker validation, and integration of patient-derived tumor models. The chemoradiosensitizing activities of the most promising drugs should be confirmed in TCD50 assays in xenograft models with/without relevant biomarker and utilizing clinically relevant radiation fractionation. We predict that appropriately validated and biomarker-directed targeted therapies will have a higher likelihood than past efforts to be successfully incorporated into the standard management of hard-to-treat tumors.

Results and molecular correlates from a pilot study of neoadjuvant induction FOLFIRINOX followed by chemoradiation and surgery for gastroesophageal adenocarcinomas

PURPOSE

We performed a NCI-sponsored, prospective study of neoadjuvant FOLFIRINOX followed by chemoradiation (CRT) with carboplatin/paclitaxel followed by surgery in patients with locally advanced gastric or gastroesophageal (GEA) cancer.

EXPERIMENTAL DESIGN

The primary objective was to determine completion rate of neoadjuvant FOLFIRINOX x 8 followed by CRT. Secondary endpoints were toxicity and pathologic complete response (pCR) rate. Exploratory analysis was performed of ctDNA to treatment response.

RESULTS

From Oct 2017 to June 2018, 25 patients were enrolled. All patients started FOLFIRINOX, 92% completed all 8 planned cycles, and 88% completed CRT. Twenty (80%) patients underwent surgical resection, and 7 had a pCR (35% in resected cohort, 28% ITT ). Tumor-specific mutations were identified in 21 (84%) patients, of whom 4 and 17 patients had undetectable and detectable ctDNA at baseline, respectively. Presence of detectable post-CRT ctDNA (p=0.004) and/or postoperative ctDNA (p=0.045) were associated with disease recurrence.

CONCLUSIONS

Here we show neoadjuvant FOLFIRINOX followed by CRT for locally advanced GEA is feasible and yields a high rate of pCR. ctDNA appears to be a promising predictor of postoperative recurrence.

Mesothelioma Risk Score: A New Prognostic Pretreatment, Clinical-Molecular Algorithm for Malignant Pleural Mesothelioma

INTRODUCTION

Prognostic models for malignant pleural mesothelioma have been limited to demographics, symptoms, and laboratory values. We hypothesize higher accuracy using both tumor and patient characteristics. The mesothelioma prognostic test (MPT) and molecular subtype based on claudin-15-to-vimentin expression ratio are molecular signatures associated with survival. Tumor volume (TV) has improved performance compared with clinical staging, whereas neutrophil-to-lymphocyte ratio (NLR) is prognostic for malignant pleural mesothelioma.

METHODS

Tumor specimens and clinical data were collected prospectively from patients who underwent extrapleural pneumonectomy (EPP) or pleurectomy and decortication (PD) during 2007 to 2014. MPT and claudin-15-to-vimentin ratio were determined by real-time quantitative polymerase chain reaction, whereas TV was assessed from preoperative scans. Risk groups were derived from combinations of adverse factors on the basis of the Cox model. Predictive accuracy was assessed using Harrell's c-index.

RESULTS

MPT, molecular subtype, TV, and NLR were independently prognostic in patients with EPP (N = 191), suggesting equal weighting in a final three-group model (c = 0.644). In the PD cohort (N = 193), MPT poor risk combined with TV greater than 200 cm³ was associated with triple the risk compared with other subgroups (hazard ratio = 2.94, 95% confidence interval: 1.70-5.09, p < 0.001) persisting when adjusted for molecular subtype, NLR, performance status, and serum albumin to yield a final three-group model (c = 0.641). The EPP and PD models achieved higher accuracy than published models (c ≤ 0.584, c ≤ 0.575) and pathologic staging (c = 0.554, c = 0.571).

CONCLUSIONS

The novel models use pretreatment parameters obtained from minimally invasive biopsy, imaging, and blood tests to evaluate the expected outcome of each type of surgery in newly diagnosed patients and improve stratification on clinical trials.

Assessment of a Contralateral Esophagus-Sparing Technique in Locally Advanced Lung Cancer Treated With High-Dose Chemoradiation: A Phase 1 Nonrandomized Clinical Trial

Importance

Severe acute esophagitis occurs in up to 20% of patients with locally advanced lung cancer treated with chemoradiation therapy to at least 60 Gy once daily and represents a dose-limiting toxic event associated with poor outcomes.

Objective

To assess whether formalized sparing of the contralateral esophagus (CE) is associated with reduced risk of severe acute esophagitis.

Design, Setting, and Participants

This single-center phase 1 nonrandomized clinical trial assessing an empirical CE-sparing technique enrolled patients from July 2015 to January 2019. In total, 27 patients with locally advanced non-small cell lung carcinoma (with or without solitary brain metastasis) or limited-stage small cell lung carcinoma with gross tumor within 1 cm of the esophagus were eligible.

Interventions

Intensity-modulated radiation therapy to 70 Gy at 2 Gy/fraction concurrent with standard chemotherapy with or without adjuvant durvalumab. The esophageal wall contralateral to gross tumor was contoured as an avoidance structure to guide a steep dose falloff gradient. Target coverage was prioritized over CE sparing, and 99% of internal and planning target volumes had to be covered by 70 Gy and at least 63 Gy, respectively.

Main Outcomes and Measures

The primary end point was the rate of at least grade 3 acute esophagitis as assessed by Common Terminology Criteria for Adverse Events, version 4.

Results

Of 27 patients enrolled, 25 completed chemoradiation therapy. Nineteen patients had non-small cell lung carcinoma, and 6 had small cell lung carcinoma. The median age at diagnosis was 67 years (range, 51-81 years), and 15 patients (60%) were men. Thirteen patients (52%) had stage IIIA cancer, 10 (40%) had stage IIIB cancer, and 2 (8%) had stage IV cancer. The median CE maximum dose was 66 Gy (range, 44-71 Gy); the median volume of CE receiving at least 55 Gy was 1.4 cm3 (range, 0-5.3 cm3), and the median volume of CE receiving at least 45 Gy was 2.7 cm3 (range, 0-9.2 cm3). The median combined percentage of lung receiving at least 20 Gy was 25% (range, 11%-37%). The median follow-up was 33.3 months (range, 11.1-52.2 months). Among the 20 patients who had treatment breaks of 0 to 3 days and were thus evaluable for the primary end point, the rate of at least grade 3 esophagitis was 0%. Other toxic events observed among all 25 patients included 7 (28%) with grade 2 esophagitis, 3 (12%) with at least grade 2 pneumonitis (including 1 with grade 5), and 2 (8%) with at least grade 3 cardiac toxic event (including 1 with grade 5). There was no isolated local tumor failure. The 2-year progression-free survival rate was 57% (95% CI, 33%-75%), and the 2-year overall survival rate was 67% (95% CI, 45%-82%).

Conclusions and Relevance

This phase 1 nonrandomized clinical trial found that the CE-sparing technique was associated with reduced risk of esophagitis among patients treated uniformly with chemoradiation therapy (to 70 Gy), with no grade 3 or higher esophagitis despite tumor within 1 cm of the esophagus. This technique may be translated into clinical practice.

Trial Registration

ClinicalTrials.gov Identifier: NCT02394548.

Preliminary results of phase 2 trial of preoperative image guided intensity modulated proton radiation therapy (IMPT) with simultaneously integrated boost (SIB) to the high-risk margin for retroperitoneal sarcomas (RPS)

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Background: RPS often have local recurrence (LR) after surgery. Preoperative radiation (RT) to 50.4 Gy can reduce LR risk but is not uniformly effective, especially after (+) margin resections. Therefore, we conducted a multi-institutional, prospective Phase II study to assess efficacy and tolerability of preop IMPT with selective dose escalation to 63 GyRBE to the posterior RPS margin (clinical target volume [CTV] 2) at high risk for (+) margins to further reduce the risk of LR. This dose was tolerable in a prior phase I study (DeLaney T et al, 2017, PMID:28740917). Methods: Primary RPS patients (pts) >18 years received preop IMPT, 50.4 GyRBE in 28 fractions (fx) of 1.8 GyRBE to CTV1 (tumor plus adjacent tissue at risk of subclinical disease) with SIB to CTV2 to 63.0 GyRBE in 28 fx of 2.25 GyRBE. Pts with high-grade tumors could get chemotherapy(CTX) prior to IMPT. To avoid treatment delay, 11 fx of IMRT x-rays could be substituted for IMPT. Pts had restaging and surgery 4-8 weeks after IMPT. Primary study endpoint was local tumor control. Secondary endpoints included clinical and pathologic response, surgical margin status, and disease-free and overall survival. Results: We accrued 60 pts from January 2016 to February 2021. Histology: 35 liposarcoma(LPS) (19 dediff and 16 well diff), 22 leiomyosarcoma(LMS), and 3 undifferentiated pleomorphic sarcoma. IMPT was delivered per protocol in all pts. 51 pts have had surgery, 5 are awaiting surgery, and 4 had no surgery due to metastases(DM) on preop imaging. 22 pts had (+) margins. 2 pts had > 75% necrosis. With 23-month median (range 1-52 months) follow-up after start of RT, there were two LRs. A dediff LPS pt had a well diff LPS LR 26 months postop, resected, and is disease-free. A renal vein/IVC LMS pt treated with CTX and IMPT had LR and DM 4 months postop and died from disease. Surgical Clavien-Dindo morbidity scores: 0(21), 1(9), 2(8), 3a (4), 3b(4), 4a(2), 4(b)1, 5(2); the periop deaths were from sepsis(pneumonia) and duodenal ulcer. The grade 3-4 periop morbidity included abscess(3), treated by catheter(2) or operative(1) drainage, prolonged hospital stays (2 pts with IVC LMS), small bowel obstruction (1), and late sigmoid colon anastomotic failure (1). Readmissions for lymphopenia(1), pneumoperitoneum (1), and volume overload (1). One late neuropathy was seen in a Type II diabetic pt with transient postop weakness after femoral nerve dissection who later had significant lower extremity weakness 3.75 years postop. Study was amended to reduce IMPT dose in diabetic pts. Conclusions: Preoperative IMPT with selective dose escalation to 63 GyRBE to the high risk posterior RPS margin is feasible. Early local control results with this approach appear promising. Some peri-operative morbidity was noted but appears to be in the expected range for RPS resections. Clinical trial information: NCT01659203.

Local and systemic recurrence following total neoadjuvant therapy (TNT) and resection for borderline resectable and locally advanced pancreatic adenocarcinoma: Long-term follow up from two phase II studies

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Background: With the advent of FOLFIRINOX, the management of pancreatic cancer has undergone a profound change. There has been a shift to TNT with FOLFIRINOX followed by radiation and an attempt at surgical resection. Recent trials of TNT have demonstrated an ability to resect locally advanced (LA) and borderline resectable disease. There is a lack of prospective data demonstrating local and systemic recurrence rates after TNT. Methods: Two previously reported prospective clinical trials (Murphy JE, et al, JAMA Oncol 2018, 2019) of total neoadjuvant therapy were conducted between 2012 and 2018 for borderline and LA disease (NCT01591733, NCT01821729). Patients received FOLFIRINOX for 8 cycles. Upon restaging, patients with resolution of vascular involvement received short-course chemoradiotherapy (5 Gy x 5 with protons or 3 Gy x 10 w photons) with capecitabine (N=34). Patients with persistent vascular involvement received long-course chemoradiotherapy with capecitabine (N=56). All patients were considered for resection after TNT except for those patients with metastatic or unresectable disease. Results: 97 eligible patients were enrolled and started treatment on the borderline resectable (n = 48) and locally advanced (n= 49) study. 90 patients completed therapy. 80 patients were taken to the operating room. 61 patients had R0 resection and 5 patients had R1 resection. The table shows the distribution of local recurrences, local recurrences and metastatic disease, and metastatic disease alone. With a median follow-up of 5.2 years (range: 2.4-6.0), of the 61 R0 patients, 22 patients remained alive and free of disease, 7 patients had a local recurrence, 4 patients had locoregional and metastatic recurrence, and 24 patients had a metastatic recurrence. 3 patients who underwent R0 resection died of unrelated causes. Median survival for patients undergoing R0 resection is 43.8 months. Conclusions: Total neoadjuvant therapy for locally advanced and borderline resectable pancreatic cancer is potentially curable and may change the pattern of spread.[Table: see text]

Clinical outcomes in a large pediatric cohort of patients with ependymoma treated with proton radiotherapy

BACKGROUND

Treatment for pediatric ependymoma includes surgical resection followed by local radiotherapy (RT). Proton RT (PRT) enables superior sparing of critical structures compared with photons, with potential to reduce late effects. We report mature outcomes, patterns of failure, and predictors of outcomes in patients treated with PRT.

METHODS

One hundred fifty patients (<22 y) with World Health Organization grades II/III ependymoma were treated with PRT between January 2001 and January 2019 at Massachusetts General Hospital. Demographic, tumor, and treatment-related characteristics were analyzed. Event-free survival (EFS), overall survival (OS), and local control (LC) were assessed.

RESULTS

Median follow-up was 6.5 years. EFS, OS, and LC for the intracranial cohort (n = 145) at 7 years were 63.4%, 82.6%, and 76.1%. Fifty-one patients recurred: 26 (51.0%) local failures, 19 (37.3%) distant failures, and 6 (11.8%) synchronous failures. One hundred sixteen patients (77.3%) underwent gross total resection (GTR), 5 (3.3%) underwent near total resection (NTR), and 29 (19.3%) underwent subtotal resection (STR). EFS for the intracranial cohort at 7 years for GTR/NTR and STR was 70.3% and 35.2%. With multivariate analysis, the effect of tumor excision persisted after controlling for tumor location. There was no adverse effect on disease control if surgery to RT interval was within 9 weeks of GTR/NTR.

CONCLUSION

PRT is effective and safe in pediatric ependymoma. Similar to previous studies, GTR/NTR was the most important prognostic factor. Intervals up to 9 weeks from surgery to PRT did not compromise disease outcomes. There was no LC benefit between patients treated with >54 Gray relative biological effectiveness (GyRBE) versus ≤54 GyRBE.

Spectrum of Mechanisms of Resistance to Crizotinib and Lorlatinib in ROS1 Fusion-Positive Lung Cancer

PURPOSE

Current standard initial therapy for advanced, ROS proto-oncogene 1, receptor tyrosine kinase fusion (ROS1)-positive (ROS1⁺) non-small cell lung cancer (NSCLC) is crizotinib or entrectinib. Lorlatinib, a next-generation anaplastic lymphoma kinase/ROS1 inhibitor, recently demonstrated efficacy in ROS1⁺ NSCLC, including in crizotinib-pretreated patients. However, mechanisms of lorlatinib resistance in ROS1⁺ disease remain poorly understood. Here, we assessed mechanisms of resistance to crizotinib and lorlatinib.

EXPERIMENTAL DESIGN

Biopsies from patients with ROS1 ⁺ NSCLC progressing on crizotinib or lorlatinib were profiled by genetic sequencing.

RESULTS

From 55 patients, 47 post-crizotinib and 32 post-lorlatinib biopsies were assessed. Among 42 post-crizotinib and 28 post-lorlatinib biopsies analyzed at distinct timepoints, ROS1 mutations were identified in 38% and 46%, respectively. ROS1 G2032R was the most commonly occurring mutation in approximately one third of cases. Additional ROS1 mutations included D2033N (2.4%) and S1986F (2.4%) post-crizotinib and L2086F (3.6%), G2032R/L2086F (3.6%), G2032R/S1986F/L2086F (3.6%), and S1986F/L2000V (3.6%) post-lorlatinib. Structural modeling predicted ROS1^L2086F causes steric interference to lorlatinib, crizotinib, and entrectinib, while it may accommodate cabozantinib. In Ba/F3 models, ROS1^L2086F, ROS1^{G2032R/L2086F}, and ROS1^{S1986F/G2032R/L2086F} were refractory to lorlatinib but sensitive to cabozantinib. A patient with disease progression on crizotinib and lorlatinib and ROS1 L2086F received cabozantinib for nearly 11 months with disease control. Among lorlatinib-resistant biopsies, we also identified MET amplification (4%), KRAS G12C (4%), KRAS amplification (4%), NRAS mutation (4%), and MAP2K1 mutation (4%).

CONCLUSIONS

ROS1 mutations mediate resistance to crizotinib and lorlatinib in more than one third of cases, underscoring the importance of developing next-generation ROS1 inhibitors with potency against these mutations, including G2032R and L2086F. Continued efforts are needed to elucidate ROS1-independent resistance mechanisms.

Association of RERG Expression with Female Survival Advantage in Malignant Pleural Mesothelioma

Sex differences in incidence, prognosis, and treatment response have been described for many cancers. In malignant pleural mesothelioma (MPM), a lethal disease associated with asbestos exposure, men outnumber women 4 to 1, but women consistently live longer than men following surgery-based therapy. This study investigated whether tumor expression of genes associated with estrogen signaling could potentially explain observed survival differences. Two microarray datasets of MPM tumors were analyzed to discover estrogen-related genes associated with survival. A validation cohort of MPM tumors was selected to balance the numbers of men and women and control for competing prognostic influences. The RAS like estrogen regulated growth inhibitor (RERG) gene was identified as the most differentially-expressed estrogen-related gene in these tumors and predicted prognosis in discovery datasets. In the sex-matched validation cohort, low RERG expression was significantly associated with increased risk of death among women. No association between RERG expression and survival was found among men, and no relationship between estrogen receptor protein or gene expression and survival was found for either sex. Additional investigations are needed to elucidate the molecular mechanisms underlying this association and its sex specificity.

The use of elevated circulating hepatocyte growth factor (HGF) level as a potential prognostic biomarker in locally advanced pancreatic cancer

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Background: The hepatocyte growth factor (HGF)/c-MET pathway has pleiotropic functions in tumor progression including invasion and cancer cell survival. The potential use of circulating plasma HGF as a prognostic biomarker is not known. Methods: This was an analysis of plasma HGF in patients enrolled in a single arm phase II study (NCT01821729) of patients with previously untreated locally advanced pancreatic ductal adenocarcinoma (PDAC) treated with FOLFIRINOX and losartan followed by chemoradiotherapy before resection was attempted (Murphy JE et al., 2019). Eligible patients from the trial included those who had undergone baseline research labs including HGF. Circulating HGF was measured in the plasma on day 1 of treatment using ELISA, and the median value was used to define high vs low levels for the purpose of analysis. The association of elevated HGF with overall survival (OS) was analyzed by univariable and multivariable Cox regression, adjusting for tumor size (≤ versus > 40 mm) and serum CA19-9 (≤ versus > 37 U/mL). Results: There were 46 eligible patients with a median follow up of 31 months. The median age was 63 (range 42-78) and 52% were female (24/46). Median tumor size was 41.4 mm (range 18–68 mm). There were 41/46 patients (89.1%) with elevated baseline CA19-9. Median baseline HGF was 1,250.55 pg/mL (range 650.9–6,459.1). Median OS was 38.4 months for patients with baseline HGF at or below the median, and 19.3 months for those with elevated HGF. On univariate analysis, elevated HGF was associated with poorer OS (HR 2.28, 95% CI 1.06–4.87, p = 0.03). On multivariate analysis, after controlling for tumor size and baseline CA19-9, elevated plasma HGF remained significantly associated with poorer OS (HR 2.58, 95% CI 1.16–5.70, p = 0.02). Conclusions: In conclusion, elevated baseline circulating plasma HGF is an independent biomarker of poorer OS in patients with locally advanced PDAC treated with neoadjuvant therapy. Further randomized studies are needed to define the negative predictive biomarker value for high plasma HGF and identify the optimal HGF range as well as determine applicability to other stages of disease. These results support the continued investigation of plasma HGF in ongoing clinical trials with PDAC patients.

The Reality of Randomized Controlled Trials for Assessing the Benefit of Proton Therapy: Critically Examining the Intent-to-Treat Principle in the Presence of Insurance Denial

Purpose

This study hypothesized that insurance denial would lead to bias and loss of statistical power when evaluating the results from an intent-to-treat (ITT), per-protocol, and as-treated analyses using a simulated randomized clinical trial comparing proton therapy to intensity modulated radiation therapy where patients incurred increasing rates of insurance denial.

Methods and Materials

Simulations used a binary endpoint to assess differences between treatment arms after applying ITT, per-protocol, and as-treated analyses. Two scenarios were developed: 1 with clinical success independent of age and another assuming dependence on age. Insurance denial was assumed possible for patients <65 years. All scenarios considered an age distribution with mean ± standard deviation: 55 ± 15 years, rates of insurance denial ranging from 0%-40%, and a sample of N = 300 patients (150 per arm). Clinical success rates were defined as 70% for proton therapy and 50% for intensity modulated radiation therapy. The average treatment effect, bias, and power were compared after applying 5000 simulations.

Results

Increasing rates of insurance denial demonstrated inherent weaknesses among all 3 analytical approaches. With clinical success independent of age, a per-protocol analysis demonstrated the least bias and loss of power. When clinical success was dependent on age, the per-protocol and ITT analyses resulted in a similar trend with respect to bias and loss of power, with both outperforming the as-treated analysis.

Conclusions

Insurance denial leads to misclassification bias in the ITT analysis, a missing data problem in the per-protocol analysis, and covariate imbalance between treatment arms in the as-treated analysis. Moreover, insurance denial forces the critical appraisal of patient features (eg, age) affected by the denial and potentially influencing clinical success. In the presence of insurance denial, our study suggests cautious reporting of ITT and as-treated analyses, and placing primary emphasis on the results of the per-protocol analysis.

A Multi-institutional Comparative Analysis of Proton and Photon Therapy-Induced Hematologic Toxicity in Patients With Medulloblastoma

PURPOSE

This multi-institutional retrospective study sought to examine the hematologic effects of craniospinal irradiation (CSI) in pediatric patients with medulloblastoma using proton or photon therapy.

METHODS AND MATERIALS

Clinical and treatment characteristics were recorded for 97 pediatric patients with medulloblastoma who received CSI without concurrent chemotherapy or with concurrent single-agent vincristine from 2000 to 2017. Groups of 60 and 37 patients underwent treatment with proton-based and photon-based therapy, respectively. Overall survival was determined by Kaplan-Meier curves with log-rank test. Comparisons of blood counts at each timepoint were conducted using multiple t tests with Bonferroni corrections. Univariate and multivariate analyses of time to grade ≥3 hematologic toxicity were performed with Cox regression analyses.

RESULTS

Median age of patients receiving proton and photon CSI was 7.5 years (range, 3.5-22.7 years) and 9.9 years (range, 3.6-19.5 years), respectively. Most patients had a diagnosis of standard risk medulloblastoma, with 86.7% and 89.2% for the proton and photon cohorts, respectively. Median total dose to involved field or whole posterior fossa was 54.0 Gy/Gy relative biological effectiveness (RBE) and median CSI dose was 23.4 Gy/Gy(RBE) (range, 18-36 Gy/Gy[RBE]) for both cohorts. Counts were significantly higher in the proton cohort compared with the photon cohort in weeks 3 to 6 of radiation therapy (RT). Although white blood cell counts did not differ between the 2 cohorts, patients receiving proton RT had significantly higher lymphocyte counts throughout the RT course. Similar results were observed when excluding patients who received vertebral body sparing proton RT or limiting to those receiving 23.4 Gy. Only photon therapy was associated with decreased time to grade ≥3 hematologic toxicity on univariate and multivariable analyses. No difference in overall survival was observed, and lymphopenia did not predict survival.

CONCLUSIONS

Patients who receive CSI using proton therapy experience significantly decreased hematologic toxicity compared with those receiving photon therapy.

Coronavirus Disease 2019 Infection in a Patient Population with Lung Cancer: Incidence, Presentation, and Alternative Diagnostic Considerations

Introduction

Lung cancer is associated with severe coronavirus disease 2019 (COVID-19) infections. Symptom overlap between COVID-19 and lung cancer may complicate diagnostic evaluation. We aimed to investigate the incidence, symptoms, differential diagnosis, and outcomes of COVID-19 in patients with lung cancer.

Methods

To determine an at-risk population for COVID-19, we retrospectively identified patients with lung cancer receiving longitudinal care within a single institution in the 12 months (April 1, 2019 to March 31, 2020) immediately preceding the COVID-19 pandemic, including an “active therapy population” treated within the last 60 days of this period. Among patients subsequently referred for COVID-19 testing, we compared symptoms, laboratory values, radiographic findings, and outcomes of positive versus negative patients.

Results

Between April 1, 2019 and March 31, 2020, a total of 696 patients received longitudinal care, including 406 (58%) in the active therapy population. Among 55 patients referred for COVID-19 testing, 24 (44%) were positive for COVID-19, representing a cumulative incidence of 3.4% (longitudinal population) and 1.5% (active therapy population). Compared with patients who were COVID-19 negative, those who were COVID-19 positive were more likely to have a supplemental oxygen requirement (11% versus 54%, p = 0.005) and to have typical COVID-19 pneumonia imaging findings (5 versus 56%, p = 0.001). Otherwise, there were no marked differences in presenting symptoms. Among patients who were COVID-19 negative, alternative etiologies included treatment-related toxicity (26%), atypical pneumonia (22%), and disease progression (22%). A total of 16 patients positive for COVID-19 (67%) required hospitalization, and seven (29%) died from COVID-related complications.

Conclusions

COVID-19 was infrequent in this lung cancer population, but these patients experienced high rates of morbidity and mortality. Oncologists should maintain a low threshold for COVID-19 testing in patients with lung cancer presenting with acute symptoms.

Large-scale analysis of BAP1 expression reveals novel associations with clinical and molecular features of malignant pleural mesothelioma

BRCA1‐associated protein‐1 (BAP1) expression is commonly lost in several tumors including malignant pleural mesothelioma (MPM). Presence or absence of immunohistochemical BAP1 nuclear staining in tumor cells is currently used for differential diagnosis of MPM. In this study, a large cohort of 596 MPM tumors with available clinical data was analyzed to examine associations of BAP1 staining pattern with clinical and molecular features that may reflect the impact of BAP1 mutation on MPM biology. Cases were classified according to the BAP1 staining pattern of tumor cells. Exome and RNA‐sequencing data were available for subsets of cases. Levels of mRNA encoding claudin 15 (CLDN15) and vimentin (VIM) were determined using RT‐qPCR on 483 cases to estimate the relative proportions of epithelial‐like and mesenchymal‐like components in each tumor. Four BAP1 staining patterns were observed: single‐pattern nuclear staining (36%), single‐pattern cytoplasmic staining (25%), single‐pattern absent staining (12%), and combinations of these staining patterns (27%). This study confirmed prior reports that nuclear BAP1 is more frequently associated with wild‐type BAP1 and sarcomatoid histology. However, no associations between BAP1 staining pattern(s) and mutations in specific protein domains and/or mutation type were observed. BAP1 staining patterns were significantly associated (p < 0.001) with BAP1 gene expression, MPM histologic subtypes, molecular clusters, and markers of epithelial‐to‐mesenchymal transition. Frequent observation of combinations of BAP1 staining patterns in MPM tumors indicated intra‐tumoral heterogeneity of BAP1 status. Cytoplasmic BAP1 staining was identified as a putative indicator of favorable prognosis in non‐epithelioid MPM. In conclusion, novel significant associations among different BAP1 staining patterns and subgroups of MPM tumors were observed, suggesting that the role of BAP1 in tumor progression may be more complex than its presumed tumor suppressor function. Cytoplasmic staining was identified as a putative indicator of favorable prognosis in non‐epithelioid MPM, potentially addressing a critical need in clinical decision‐making in this disease. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

A Phase II Trial of Cabozantinib in Hormone Receptor-Positive Breast Cancer with Bone Metastases

BACKGROUND

We assessed the antitumor activity of cabozantinib, a potent multireceptor oral tyrosine kinase inhibitor, in patients with hormone receptor-positive breast cancer with bone metastases.

PATIENTS AND METHODS

In this single-arm multicenter phase II study, patients received an initial starting dose of 100 mg, later reduced to 60 mg, per day. The primary endpoint was the bone scan response rate. Secondary endpoints included objective response rate by RECIST, progression-free survival (PFS), and overall survival (OS).

RESULTS

Of 52 women enrolled, 20 (38%) experienced a partial response on bone scan and 6 (12%) had stable disease. Prior to the first repeat bone scan at 12 weeks, 19 (35%) patients discontinued study treatment because of early clinical progression or unacceptable toxicity. RECIST evaluation based on best overall response by computed tomography revealed stable disease in extraosseous tissues in 26 patients (50%) but no complete or partial responses. In 25 patients with disease control on bone scan at 12 weeks, only 3 (12%) patients developed extraosseous progression. The median PFS was 4.3 months, and median OS was 19.6 months. The most common grade 3 or 4 toxicities were hypertension (10%), anorexia (6%), diarrhea (6%), fatigue (4%), and hypophosphatemia (4%).

CONCLUSION

Bone scans improved in 38% of patients with metastatic hormone receptor-positive breast cancer and remained stable in an additional 12% for a minimum duration of 12 weeks on cabozantinib. Further investigations should assess the activity of cabozantinib in combination with other hormonal and other breast cancer therapies and determine whether bone scan responses correlate with meaningful antitumor effects. ClinicalTrials.gov identifier. NCT01441947 IMPLICATIONS FOR PRACTICE: Most patients with metastatic hormone receptor-positive (HR+) breast cancer have bone involvement, and many have bone-only disease, which is difficult to evaluate for response. This phase II single-arm study evaluated the clinical activity of the small molecule MET/RET/VEGFR2 inhibitor cabozantinib in patients with metastatic HR+ breast cancer with bone metastases. This study met its primary endpoint, and cabozantinib treatment resulted in a significant bone scan response rate correlating with improved survival. This is the first study to use bone scan response as a primary endpoint in breast cancer. The results support further study of cabozantinib in HR+ breast cancer.

Resistance to lorlatinib in ROS1 fusion-positive non-small cell lung cancer

9611

Background: Lorlatinib is a potent, brain-penetrant ROS1/ALK tyrosine kinase inhibitor (TKI), which has demonstrated efficacy in advanced ROS1 fusion-positive (ROS1+) non-small cell lung cancer (NSCLC), including in patients (pts) previously treated with crizotinib. Despite initial benefit, however, most pts experience disease progression on lorlatinib. Mechanisms of resistance to lorlatinib in ROS1+ NSCLC are poorly understood. Methods: We analyzed repeat tumor biopsies derived from advanced ROS1+ lung cancer pts progressing on lorlatinib. Next-generation sequencing (NGS, n = 17) or whole exome sequencing (n = 1) was performed to detect mutations, indels, and copy number alterations. Results: Sixteen pts underwent a total of 18 repeat tumor biopsies after progression on lorlatinib. Fourteen had received prior crizotinib; two received prior crizotinib and entrectinib. Median duration of therapy on lorlatinib was 13.5 months (95% CI, 8.3-18.4). Among the 18 cases analyzed by sequencing, 7 (38.9%) harbored a ROS1 resistance mutation, including G2032R (4/18, 22.2%), S1986F/L2000V (1/18, 5.6%), L2086F (1/18, 5.6%), and G2032R/S1986F/L2086F (1/18, 5.6%). Of note, ROS1 L2086F was a novel resistance mutation not previously reported in the literature, but analogous to ALK L1256F (a lorlatinib-resistant ALK mutation). Structural modeling studies showed that ROS1 L2086F causes steric interference with binding of lorlatinib, as well as crizotinib and entrectinib. In addition to ROS1 kinase domain mutations, NGS analyses also identified MET copy number gain in a lorlatinib-resistant case, validated by fluorescence in situ hybridization as high-level focal MET amplification (MET/CEP7 copy number ratio 6.3) without a concomitant ROS1 resistance mutation. Duration of therapy on lorlatinib was significantly shorter in pts with a post-lorlatinib ROS1 resistance mutation compared to those without (8.3 vs 18.1 months; p = 0.005). Conclusions: ROS1 resistance mutations are observed in over one-third of cases progressing on lorlatinib, including the solvent front mutation G2032R and a novel L2086F mutation. These findings underscore the importance of developing next-generation ROS1 TKIs with activity against ROS1 mutations, and the need to elucidate ROS1-independent resistance mechanisms.

A phase II trial of cabozantinib in hormone receptor-positive breast cancer with bone metastases

1062

Background: We assessed the antitumor activity of cabozantinib, a potent multi-receptor oral tyrosine kinase inhibitor with activity against MET, RET, VEGFR2, and AXL, in patients with hormone-receptor positive (HR+) breast cancer with bone metastases. Methods: In this single-arm multicenter phase II study, patients with HR+, HER2- metastatic breast cancer and ≥ 1 prior line of therapy received an initial starting dose of 100 mg cabozantinib, later reduced to 60 mg per day. The primary endpoint was bone scan response rate determined by independent central review and defined as percent change of bone scan area from baseline. The target bone scan response rate was 30% compared to a null response rate of 10%. Secondary endpoints included objective response rate (ORR) by RECIST v1.1, progression free (PFS) and overall survival (OS). Bone scan and CT were obtained every 12 weeks. Results: Among 52 enrolled patients, median age was 55, and 54% and 42% had > 2 lines prior endocrine and chemotherapy, respectively and 18 (35%) had bone-only disease. 20 (38%) experienced a partial bone scan response and 6 (12%) had stable disease (SD). 16 (31%) patients discontinued study prior to week 12 assessment for early clinical progression or toxicity, and three (6%) had missing follow-up scans. Best extra-osseous overall response revealed SD in 26 (50%), but no objective responses. In 25 patients with bone scan disease control at 12 weeks, only 3 (12%) developed extra-osseous progression. Median PFS was 4.3 months (90% CI 2.8 - 5.5) and OS was 19.6 months (90% CI 18.0 – 26.8). In a landmark analysis, patients with bone scan disease control at 12 weeks had longer OS (median 24.2 months, 90% CI 16.4 – 31.7) than those without (median OS 13.3 months, 90% CI 9.5 – 18.2), with a hazard ratio of 0.37 (90% CI 0.21 – 0.65). Most common grade 3 or 4 toxicities were hypertension (10%), anorexia (6%), diarrhea (6%), fatigue (4%) and hypophosphatemia (4%). Dose reduction or delay occurred in 42 (81%) patients. Conclusions: This study met its primary endpoint with bone scans improved in 38% of patients with metastatic HR+ breast cancer and remained stable in an additional 12% with cabozantinib treatment. Bone scan response correlated with improved OS. This is the first reported study in breast cancer to use bone scan response as a primary endpoint. Further studies with cabozantinib in HR+ breast cancer and additional validation of bone scan response as a surrogate for clinical benefit in breast cancer are warranted. Clinical trial information: NCT01441947 .

Dosimetric Analysis and Normal-Tissue Complication Probability Modeling of Child-Pugh Score and Albumin-Bilirubin Grade Increase After Hepatic Irradiation

PURPOSE

This study aimed to develop robust normal-tissue complication probability (NTCP) models for patients with hepatocellular carcinoma treated with radiation therapy (RT) using Child-Pugh (CP) score and albumin-bilirubin (ALBI) grade increase as endpoints for hepatic toxicity.

METHODS AND MATERIALS

Data from 108 patients with hepatocellular carcinoma treated with RT between 2008 and 2017 were evaluated, of which 47 patients (44%) were treated with proton RT. Of these patients, 29 received stereotactic body RT and 79 moderately hypofractionated RT to median physical tumor doses of 43 Gy in 5 fractions and 59 Gy in 15 fractions, respectively. A generalized Lyman-Kutcher-Berman (LKB) model was used to model the NTCP using 2 clinical endpoints, both evaluated at 3 months after RT: CP score increase of ≥2 and ALBI grade increase of ≥1 from the pre-RT baseline. Confidence intervals on LKB fit parameters were determined using bootstrap resampling.

RESULTS

Compared with previous NTCP models, this study found a stronger correlation between normal liver volume receiving low doses of radiation (5-10 Gy) and a CP score or ALBI grade increase. A CP score increase exhibited a stronger correlation to normal liver volumes irradiated than an ALBI grade increase. LKB models for CP increase found values for the volume-effect parameter of a = 0.06 for all patients, and a = 0.02/0.09 when fit to photon/proton patients separately. Subset analyses for patients with superior initial liver functions showed consistent dose-volume effects (a = 0.1) and consistent dose-response relationships.

CONCLUSIONS

This study presents an update of liver NTCP models in the era of modern RT techniques using relevant endpoints of hepatic toxicity, CP score and ALBI grade increase. The results show a stronger influence of low-dose bath on hepatic toxicity than those found in previous studies, indicating that RT techniques that minimize the low-dose bath may be beneficial for patients.

MET Alterations Are a Recurring and Actionable Resistance Mechanism in ALK-Positive Lung Cancer

PURPOSE

Most ALK-positive lung cancers will develop ALK-independent resistance after treatment with next-generation ALK inhibitors. MET amplification has been described in patients progressing on ALK inhibitors, but frequency of this event has not been comprehensively assessed.

EXPERIMENTAL DESIGN

We performed FISH and/or next-generation sequencing on 207 posttreatment tissue (n = 101) or plasma (n = 106) specimens from patients with ALK-positive lung cancer to detect MET genetic alterations. We evaluated ALK inhibitor sensitivity in cell lines with MET alterations and assessed antitumor activity of ALK/MET blockade in ALK-positive cell lines and 2 patients with MET-driven resistance.

RESULTS

MET amplification was detected in 15% of tumor biopsies from patients relapsing on next-generation ALK inhibitors, including 12% and 22% of biopsies from patients progressing on second-generation inhibitors or lorlatinib, respectively. Patients treated with a second-generation ALK inhibitor in the first-line setting were more likely to develop MET amplification than those who had received next-generation ALK inhibitors after crizotinib (P = 0.019). Two tumor specimens harbored an identical ST7-MET rearrangement, one of which had concurrent MET amplification. Expressing ST7-MET in the sensitive H3122 ALK-positive cell line induced resistance to ALK inhibitors that was reversed with dual ALK/MET inhibition. MET inhibition resensitized a patient-derived cell line harboring both ST7-MET and MET amplification to ALK inhibitors. Two patients with ALK-positive lung cancer and acquired MET alterations achieved rapid responses to ALK/MET combination therapy.

CONCLUSIONS

Treatment with next-generation ALK inhibitors, particularly in the first-line setting, may lead to MET-driven resistance. Patients with acquired MET alterations may derive clinical benefit from therapies that target both ALK and MET.

Total Neoadjuvant Therapy With FOLFIRINOX in Combination With Losartan Followed by Chemoradiotherapy for Locally Advanced Pancreatic Cancer: A Phase 2 Clinical Trial

Importance

Patients with locally advanced pancreatic cancer have historically poor outcomes. Evaluation of a total neoadjuvant approach is warranted.

Objective

To evaluate the margin-negative (R0) resection rate of neoadjuvant FOLFIRINOX (fluorouracil, leucovorin, oxaliplatin, and irinotecan) and losartan followed by chemoradiotherapy for locally advanced pancreatic cancer.

Design, Setting, and Participants

A single-arm phase 2 clinical trial was conducted at a large academic hospital from August 22, 2013, to May 22, 2018, among 49 patients with previously untreated locally advanced unresectable pancreatic cancer as determined by multidisciplinary review. Patients had Eastern Cooperative Oncology Group performance status 0 or 1 and adequate hematologic, renal, and hepatic function. Median follow-up for the analysis was 17.1 months (range, 5.0-53.7) among 27 patients still alive at study completion.

Interventions

Patients received FOLFIRINOX and losartan for 8 cycles. Patients with radiographically resectable tumor after chemotherapy received short-course chemoradiotherapy (5 GyE × 5 with protons) with capecitabine. Patients with persistent vascular involvement received long-course chemoradiotherapy (50.4 Gy with a vascular boost to 58.8 Gy) with fluorouracil or capecitabine.

Main Outcomes and Measures

R0 resection rate.

Results

Of the 49 patients (26 women and 23 men; median age 63 years [range, 42-78 years]), 39 completed 8 cycles of FOLFIRINOX and losartan; 10 patients had fewer than 8 cycles due to progression (5 patients), losartan intolerance (3 patients), and toxicity (2 patients). Seven patients (16%) had short-course chemoradiotherapy while 38 (84%) had long-course chemoradiotherapy. Forty-two (86%) patients underwent attempted surgery, with R0 resection achieved in 34 of 49 patients (69%; 95% CI, 55%-82%). Overall median progression-free survival was 17.5 months (95% CI: 13.9-22.7) and median overall survival was 31.4 months (95% CI, 18.1-38.5). Among patients who underwent resection, median progression-free survival was 21.3 months (95% CI, 16.6-28.2), and median overall survival was 33.0 months (95% CI, 31.4 to not reached).

Conclusions and Relevance

Total neoadjuvant therapy with FOLFIRINOX, losartan, and chemoradiotherapy provides downstaging of locally advanced pancreatic ductal adenocarcinoma and is associated with an R0 resection rate of 61%.

Trial Registration

ClinicalTrials.gov identifier: NCT01821729.

A pilot study of durvalumab/tremelimumab (durva/treme) and radiation (XRT) for metastatic biliary tract cancer (mBTC): Preliminary safety and efficacy

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Background: Metastatic biliary tract cancer (mBTC) is a lethal malignancy with median 5 year OS of less than 10%. Immunotherapy, particularly single agent anti-PD-1/PD-L1, has limited efficacy in mBTC with ORR~9-15%. Recently presented data shows responses in metastatic MSS pancreatic or colon cancer with combination anti-PD-1/CTLA-4 and radiation (XRT) to produce systemic response (abscopal effect) (Parikh A, GI ASCO 2019, ASCO 2019.). We evaluate safety and efficacy of dual PD-1/CTLA-4 inhibition with XRT in MSS mBTC. Methods: 15 of a planned 15 mBTC patients were enrolled. Eligible pts had histologically-confirmed mBTC, ECOG-PS 0/1, and must have progressed on at least one line of previous therapy or refused standard therapy. Safety cohort of 6 pts of durva 1500 mg/treme 75 mg q4w was enrolled. If > 2 DLTs, patients were enrolled subsequently to dose level -1 (durva 1125 mg/ treme 75 mg q4w). 3 fractions of 8 Gy of radiation at C2D1 every other day to a single metastatic site. Durva/treme continued for 4 cycles, followed by 4 cycles of maintenance durva until progressive disease, discontinuation or withdrawal. Endpoints include disease control rate (DCR (SD+PR+CR)), PFS and OS and safety. Radiological evaluations were done q2 mo. Results: 15 mBTC pts enrolled and evaluable from May 2018 to March 2019. Median age 63 years (range 48-75), 47% male. DLTs occurred in 3 patients during the safety run-in. One patient experienced DLT at dose level -1 and subsequent expansion. 3 patients did NOT reach radiation therapy. DCR was 27% with a 13% PR and 7% CR. Of those who reached radiation, DCR was 33% with a 17% PR and 8% CR. At time of analysis, median PFS was 54 days for ITT mBTC. Duration of response for 4 patients with DCR was 26, 52, 122, 254+ days. Treatment-related adverse events were reported in 12/15 patients (80%). Grade ≥3 toxicities were seen in 9/15 pts (60%) with lymphopenia (5 grade 3) and elevated LFTs (2 grade 4 and 4 grade 2) being the main adverse events. All patients with disease control were not MSI. Conclusions: Combination of durva/treme XRT is feasible and shows preliminary activity in metastatic BTC. An expansion cohort is being planned to confirm activity. Clinical trial information: NCT03482102.

Clinical activity of programmed cell death 1 (PD-1) blockade in never, light, and heavy smokers with non-small-cell lung cancer and PD-L1 expression ≥50

Background:

Immune checkpoint inhibitors (ICIs) are standard therapies for patients with advanced non-small-cell lung cancer (NSCLC) and a programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) ≥50%. Tumor mutation burden (TMB) also predicts response to ICIs but is often not available in real time for decision making in the first-line setting. Smoking exposure can be a proxy for TMB in NSCLC. The impact of smoking status on efficacy of PD-1 blockade in NSCLC patients with PD-L1 TPS ≥50% has not been well defined.

Patients and methods:

To investigate the relationship between smoking and activity of ICIs in NSCLC, we retrospectively studied 315 patients with NSCLC and PD-L1 TPS ≥50% at five USA academic medical centers. Objective response rates (ORRs), progression-free survival (PFS), and duration of response (DOR) were compared between never (<100 lifetime cigarettes), light (≤10 pack-years), and heavy (>10 pack-years) smokers. A subset of patients underwent next-generation sequencing to estimate TMB.

Results:

We identified 36 (11%) never, 42 (13%) light, and 237 (75%) heavy smokers with NSCLC and PD-L1 TPS ≥50% treated with ICIs. Objective responses were observed in 27%, 40%, and 40% of never, light, and heavy smokers, respectively (P = 0.180 never versus heavy; P = 1.000 light versus heavy). Median PFS and median DOR were numerically shorter in never and light smokers compared with heavy smokers (PFS 3.0 versus 4.0 versus 5.4 months; median DOR 6.9 versus 10.8 versus 17.8 months), but were not statistically different [PFS: hazard ratio (HR) 1.37, P = 0.135 and HR 1.24, P = 0.272; DOR: HR 1.92, P = 0.217 and HR 1.79, P = 0.141].

Conclusions:

PD-(L)1 inhibitors are associated with antitumor activity in NSCLC with PD-L1 TPS ≥50% regardless of smoking status. Nevertheless, there is a signal of potentially decreased durability among never and light smokers that should be further evaluated. Distinct immunobiologic features may affect initial response versus durability of antitumor immunity to programmed cell death 1 (PD-1) blockade.

An open invitation to join the Pediatric Proton/Photon Consortium Registry to standardize data collection in pediatric radiation oncology

OBJECTIVE

The Pediatric Proton/Photon Consortium Registry (PPCR) is a comprehensive data registry composed of pediatric patients treated with radiation. It was established to expedite outcomes-based research. The attributes which allow the PPCR to be a successful collaboration are reviewed.

METHODS AND MATERIALS

Current eligibility criteria are radiotherapy patients < 22 years treated at one of the 15 US participating institutions. Detailed health and treatment data are collected about the disease presentation and treatment exposures, and annually thereafter, in REDCap (Research Electronic Data Capture). DICOM (Digital Imaging and Communications in Medicine) imaging and radiation plans are collected through MIM/MIMcloud. An optional patient-reported quality-of-life (PedsQL) study is administered at 10 sites.

RESULTS

Accrual started October 2012 with 2,775 participants enrolled as of 25 July 2019. Most patients, 62.0%, were treated for central nervous system (CNS) tumors, the most common of which are medulloblastoma (n = 349), ependymoma (n = 309), and glial/astrocytoma tumors (n = 279). The most common non-CNS diagnoses are rhabdomyosarcoma (n = 284), Ewing's sarcoma (n = 153), and neuroblastoma (n = 130). While the majority of participants are US residents, 18.7% come from 36 other countries. Over 685 patients participate in the PedsQL study.

CONCLUSIONS

The PPCR is a valuable research platform capable of answering countless research questions that will ultimately improve patient care. Centers outside of the USA are invited to participate directly or may engage with the PPCR to align data collection strategies to facilitate large-scale international research.

ADVANCES IN KNOWLEDGE

For investigators looking to carry out research in a large pediatric oncology cohort or interested in registry work, this paper provides an updated overview of the PPCR.