Perioperative and oncologic outcomes of pulmonary resection for synchronous oligometastatic non-small cell lung cancer: Evidence for surgery in advanced disease

OBJECTIVES

Recent randomized trials have demonstrated a survival advantage with the use of local consolidative therapy in oligometastatic non-small cell lung cancer; however, the indications for and outcomes after pulmonary resection as a component of local consolidative therapy remain ill defined. We sought to characterize the perioperative and long-term survival outcomes among patients with resected oligometastatic non-small cell lung cancer.

METHODS

Patients presenting to a single center (2000-2017) with oligometastatic non-small cell lung cancer (≤3 synchronous metastases, intrathoracic nodal disease counted as a single site) who underwent resection of the primary tumor were retrospectively identified. Charts were reviewed, and demographic, clinical, pathologic, oncologic, and survival outcomes were recorded. Survival outcomes were analyzed from the date of surgery.

RESULTS

A total of 52 patients met inclusion criteria, among whom most (38, 73.1%) were ever smokers, had nonsquamous tumors (48, 92.3%), had no intrathoracic nodal disease (33, 63.5%), and had 1 to 2 sites of metastases (49, 94.2%). The majority (41, 78.9%) received systemic therapy, predominantly in the neoadjuvant setting (24/41, 58.5%). After resection, there were no 30- or 90-day deaths. After a median follow-up of 94.6 months (95% CI, 69.0-139.1), 37 patients (71.2%) progressed and 38 patients (73.1%) died. Median postoperative progression-free survival and overall survival were 9.4 (5.5-11.6) months and 51.7 (22.3-65.3) months, respectively.

CONCLUSIONS

Pulmonary resection as a means of maximum locoregional control in oligometastatic non-small cell lung cancer is feasible and safe, and may be associated with durable long-term survival benefits. The frequency of systemic postoperative progression highlights an urgent need to characterize perioperative and oncologic outcomes after pulmonary resection in the current era of novel systemic therapies.

Biomarkers associated with pulmonary exacerbations in a randomized trial of nintedanib for radiation pneumonitis

BACKGROUND AND PURPOSE

Radiation pneumonitis (RP) is a common side effect of thoracic radiotherapy and often has a long course characterized by acute exacerbations and progression to permanent lung fibrosis. There are no validated biomarkers of prognosis in patients diagnosed with RP.

MATERIALS AND METHODS

We analyzed a time course of serum chemokines, cytokines, and other proteins from patients with grade 2+ RP in a randomized clinical trial of a steroid taper plus nintedanib, a multiple tyrosine kinase inhibitor, versus placebo plus a steroid taper for the treatment of RP. Weighted gene correlation network analysis (WGCNA) and univariable zero inflated Poisson models were used to identify groups of correlated analytes and their associations with clinical outcomes.

RESULTS

Thirty enrolled patients had biomarker data available, and 17 patients had enough analytes tested for network analysis. WGNCA identified ten analytes, including transforming growth factor beta-1 (TGF-β1), monocyte chemoattractant protein-1 (MCP-1), and platelet-derived growth factor (PDGF), that in aggregate were correlated with the occurrence of pulmonary exacerbations (p = 0.008), the total number of acute pulmonary exacerbations (p = 0.002), and treatment arm (p = 0.036). By univariable analysis, an increase in rate of change of two components of the RP module were associated with an increased incidence rate of pulmonary exacerbations: interleukin 5 (IL-5, incidence rate ratio (IRR) 1.02, 95% CI 1.01-1.04, p = 0.002), and tumor necrosis factor superfamily 12 (TNFSF12, IRR 1.06, CI 1-1.11, p = 0.036). An increased slope of epidermal growth factor (EGF) was associated with a decreased incidence rate of exacerbations (IRR 0.94, CI 0.89-1, p = 0.036).

CONCLUSION

We identified a panel of serum biomarkers that showed association with nintedanib treatment and acute pulmonary exacerbations in patients with RP. A confirmatory study will be needed to validate this panel for use as a prognostic tool in patients with RP.

Evaluating a Physician Audit and Feedback Intervention to Increase Clinical Trial Enrollment in Radiation Oncology in a Multisite Tertiary Cancer Center: A Randomized Study

PURPOSE

Clinical trial participation continues to be low, slowing new cancer therapy development. Few strategies have been prospectively tested to address barriers to enrollment. We investigated the effectiveness of a physician audit and feedback report to improve clinical trial enrollment.

METHODS AND MATERIALS

We conducted a randomized quality improvement study among radiation oncologists at a multisite tertiary cancer network. Physicians in the intervention group received quarterly audit and feedback reports comparing the physician's trial enrollments with those of their peers. The primary outcome was trial enrollments.

RESULTS

Among physicians randomized to receive the feedback report (n = 30), the median proportion of patients enrolled during the study period increased to 6.1% (IQR, 2.6%-9.3%) from 3.2% (IQR, 1.1%-10%) at baseline. Among those not receiving the feedback report (n = 29), the median proportion of patients enrolled increased to 4.1% (IQR, 1.3%-7.6%) from 1.6% (IQR, 0%-4.1%) at baseline. There was a nonsignificant change in the proportion of enrollments associated with receiving the feedback report (-0.6%; 95% CI, -3.0% to 1.8%; P = .6). Notably, there was an interaction between baseline trial accrual and receipt of feedback reports (P = .005), with enrollment declining among high accruers. There was an increase in enrollment throughout the study, regardless of study group (P = .001).

CONCLUSIONS

In this study, a positive effect of physician audit and feedback on clinical trial enrollment was not observed. Future efforts should avoid disincentivizing high accruers and might consider pairing feedback with other patient- or physician-level strategies. The increase in trial enrollment in both groups over time highlights the importance of including a comparison group in quality improvement studies to reduce confounding from secular trends.

An 18F-FDG PET/CT and Mean Lung Dose Model to Predict Early Radiation Pneumonitis in Stage III Non-Small Cell Lung Cancer Patients Treated with Chemoradiation and Immunotherapy

Radiation pneumonitis (RP) that develops early (i.e., within 3 mo) (RPEarly) after completion of concurrent chemoradiation (cCRT) leads to treatment discontinuation and poorer survival for patients with stage III non-small cell lung cancer. Since no RPEarly risk model exists, we explored whether published RP models and pretreatment 18F-FDG PET/CT-derived features predict RPEarly Methods: One hundred sixty patients with stage III non-small cell lung cancer treated with cCRT and consolidative immunotherapy were analyzed for RPEarly Three published RP models that included the mean lung dose (MLD) and patient characteristics were examined. Pretreatment 18F-FDG PET/CT normal-lung SUV featured included the following: 10th percentile of SUV (SUVP10), 90th percentile of SUV (SUVP90), SUVmax, SUVmean, minimum SUV, and SD. Associations between models/features and RPEarly were assessed using area under the receiver-operating characteristic curve (AUC), P values, and the Hosmer-Lemeshow test (pHL). The cohort was randomly split, with similar RPEarly rates, into a 70%/30% derivation/internal validation subset. Results: Twenty (13%) patients developed RPEarly Predictors for RPEarly were MLD alone (AUC, 0.72; P = 0.02; pHL, 0.87), SUVP10, SUVP90, and SUVmean (AUC, 0.70-0.74; P = 0.003-0.006; pHL, 0.67-0.70). The combined MLD and SUVP90 model generalized in the validation subset and was deemed the final RPEarly model (RPEarly risk = 1/[1+e(- x )]; x = -6.08 + [0.17 × MLD] + [1.63 × SUVP90]). The final model refitted in the 160 patients indicated improvement over the published MLD-alone model (AUC, 0.77 vs. 0.72; P = 0.0001 vs. 0.02; pHL, 0.65 vs. 0.87). Conclusion: Patients at risk for RPEarly can be detected with high certainty by combining the normal lung's MLD and pretreatment 18F-FDG PET/CT SUVP90 This refined model can be used to identify patients at an elevated risk for premature immunotherapy discontinuation due to RPEarly and could allow for interventions to improve treatment outcomes.

Disparities in Stage at Presentation Among Hispanic and Latinx Patients With Non-Small-Cell Lung Cancer in the United States

PURPOSE

Hispanic and Latinx people in the United States are the fastest-growing ethnic group. However, previous studies in non-small-cell lung cancer (NSCLC) often analyze these diverse communities in aggregate. We aimed to identify differences in NSCLC stage at diagnosis in the US population, focusing on disaggregated Hispanic/Latinx individuals.

METHODS

Data from the National Cancer Database from 2004 to 2018 identified patients with primary NSCLC. Individuals were disaggregated by racial and ethnic subgroup and Hispanic country of origin. Ordinal logistic regression adjusting for age, facility type, income, educational attainment, comorbidity index, insurance, and year of diagnosis was used to create adjusted odds ratios (aORs), with higher odds representing diagnosis at later-stage NSCLC.

RESULTS

Of 1,565,159 patients with NSCLC, 46,616 were Hispanic/Latinx (3.0%). When analyzed in the setting of race and ethnicity, Hispanic patients were more likely to be diagnosed with metastatic disease compared with non-Hispanic White (NHW) patients: 47.0% for Hispanic Black, 46.0% Hispanic White, and 44.3% of Hispanic other patients versus 39.1% of non-Hispanic White patients (P < .001 for all). By country of origin, 51.4% of Mexican, 41.7% of Puerto Rican, 44.6% of Cuban, 50.8% of South or Central American, 48.4% of Dominican, and 45.6% of other Hispanic patients were diagnosed with metastatic disease, compared with 39.1% of NHWs. Conversely, 20.2% of Mexican, 26.9% of Puerto Rican, 24.2% of Cuban, 22.5% of South or Central American, 23.7% of Dominican, and 24.5% of other Hispanic patients were diagnosed with stage I disease, compared with 30.0% of NHWs. All Hispanic groups were more likely to present with later-stage NSCLC than NHW patients (greatest odds for Mexican patients, aOR, 1.44; P < .001).

CONCLUSION

Hispanic/Latinx patients with non-small-cell lung cancer were more likely to be diagnosed with advanced disease compared with NHWs. Disparities persisted upon disaggregation by both race and country of origin, with over half of Mexican patients with metastatic disease at diagnosis. Disparities among Hispanic/Latinx groups by race and by country of origin highlight the shortcomings of treating these groups as a monolith and underscore the need for disaggregated research and targeted interventions.

Clinical outcomes of stereotactic body radiation therapy for malignant pleural mesothelioma

BACKGROUND

The objective of this study is to determine the outcomes and toxicities of patients with malignant pleural mesothelioma (MPM) treated with stereotactic body radiotherapy (SBRT).

MATERIALS AND METHODS

Data were extracted from an institutional tumor registry for patients diagnosed with mesothelioma and treated with SBRT. Kaplan-Meier and Cox regression analyses were employed to determine local control (LC) and overall survival (OS).

RESULTS

Forty-four patients with 59 total treated tumors from December 2006 to April 2022 were identified. Fifty-one (86.4 %) cases had oligoprogressive disease (five sites or less). The median prescription dose delivered was 3000 cGy in 5 fractions (range: 2700-6000 cGy in 3-8 fractions). Fifty-one (86.4 %) tumors were in the pleura, 4 (6.8 %) spine, 2 (3.4 %) bone, 1 (1.7 %) brain, and 1 (1.7 %) pancreas. The median follow-up from SBRT completion for those alive at last follow-up was 28 months (range: 14-52 months). The most common toxicities were fatigue (50.8 %), nausea (22.0 %), pain flare (15.3 %), esophagitis (6.8 %), dermatitis (6.8 %), and pneumonitis (5.1 %). There were no grade ≥ 3 acute or late toxicities. There were 2 (3.4 %) local failures, one of the pleura and another of the spine. One-year LC was 92.9 % (95 % CI: 74.6-98.2 %) for all lesions and 96.3 % (95 % CI: 76.5-99.5 %) for pleural tumors. One-year LC was 90.9 % (95 % CI: 68.1-97.6 %) for epithelioid tumors and 92.1 % (95 % CI: 72.1-98.0 %) for oligoprogressive tumors. One-year OS from time of SBRT completion was 36.4 % (95 % CI: 22.6-50.3 %). On multivariable analysis, KPS was the lone significant predictor for OS (p = 0.029).

CONCLUSIONS

Our single-institutional experience on patients with MPM suggests that SBRT is safe with a low toxicity profile and potentially achieve good local control.

Impact of Pretreatment Weight Loss on Radiotherapy Utilization and Clinical Outcomes in Non-Small Cell Lung Cancer

BACKGROUND

Cancer cachexia is a syndrome of unintentional weight loss resulting in progressive functional impairment. Knowledge of radiation therapy utilization in patients with cancer cachexia is limited. We evaluated the use of curative and palliative-intent radiation for the management of patients with non-small cell lung cancer (NSCLC) with cachexia to determine whether tumor-directed therapy affected cachexia-associated outcomes.

METHODS

Using an Institutional Tumor Registry, we evaluated all patients with stages of NSCLC treated at a tertiary care system from 2006 to 2013. We adopted the international consensus definition for cachexia, with staging designated by the registry and positron emission tomography. Radiotherapy delivery and intent were retrospectively assessed.

RESULTS

In total, 1330 patients with NSCLC were analyzed. Curative-intent radiotherapy was utilized equally between patients with cachexia and non-cachexia with stages I to III NSCLC. Conversely, significantly more patients with stage IV disease and cachexia received palliative radiotherapy versus those without (74% vs 63%, P = 0.006). Cachexia-associated survival was unchanged irrespective of tumor-directed radiation therapy with curative or palliative intent. In fact, pretreatment cachexia was associated with reduced survival for patients with stage III NSCLC receiving curative-intent radiotherapy (median survival = 23.9 vs 15.0 mo, P = 0.009). Finally, multivariate analysis identified pretreatment cachexia as an independent variable associated with worsened survival (hazard ratio = 1.31, CI: 1.14,1.52).

CONCLUSION

Patients with advanced NSCLC with cachexia received more palliative-intent radiation than those without weight loss. Tumor-directed therapy in either a curative or palliative approach failed to alter cachexia patient survival across all stages of the disease. These findings offer critical information on the appropriate utilization of radiation in the management of patients with NSCLC with cachexia.

Standard-of-care systemic therapy with or without stereotactic body radiotherapy in patients with oligoprogressive breast cancer or non-small-cell lung cancer (Consolidative Use of Radiotherapy to Block [CURB] oligoprogression): an open-label, randomised, controlled, phase 2 study

BACKGROUND

Most patients with metastatic cancer eventually develop resistance to systemic therapy, with some having limited disease progression (ie, oligoprogression). We aimed to assess whether stereotactic body radiotherapy (SBRT) targeting oligoprogressive sites could improve patient outcomes.

METHODS

We did a phase 2, open-label, randomised controlled trial of SBRT in patients with oligoprogressive metastatic breast cancer or non-small-cell lung cancer (NSCLC) after having received at least first-line systemic therapy, with oligoprogression defined as five or less progressive lesions on PET-CT or CT. Patients aged 18 years or older were enrolled from a tertiary cancer centre in New York, NY, USA, and six affiliated regional centres in the states of New York and New Jersey, with a 1:1 randomisation between standard of care (standard-of-care group) and SBRT plus standard of care (SBRT group). Randomisation was done with a computer-based algorithm with stratification by number of progressive sites of metastasis, receptor or driver genetic alteration status, primary site, and type of systemic therapy previously received. Patients and investigators were not masked to treatment allocation. The primary endpoint was progression-free survival, measured up to 12 months. We did a prespecified subgroup analysis of the primary endpoint by disease site. All analyses were done in the intention-to-treat population. The study is registered with ClinicalTrials.gov, NCT03808662, and is complete.

FINDINGS

From Jan 1, 2019, to July 31, 2021, 106 patients were randomly assigned to standard of care (n=51; 23 patients with breast cancer and 28 patients with NSCLC) or SBRT plus standard of care (n=55; 24 patients with breast cancer and 31 patients with NSCLC). 16 (34%) of 47 patients with breast cancer had triple-negative disease, and 51 (86%) of 59 patients with NSCLC had no actionable driver mutation. The study was closed to accrual before reaching the targeted sample size, after the primary efficacy endpoint was met during a preplanned interim analysis. The median follow-up was 11·6 months for patients in the standard-of-care group and 12·1 months for patients in the SBRT group. The median progression-free survival was 3·2 months (95% CI 2·0-4·5) for patients in the standard-of-care group versus 7·2 months (4·5-10·0) for patients in the SBRT group (hazard ratio [HR] 0·53, 95% CI 0·35-0·81; p=0·0035). The median progression-free survival was higher for patients with NSCLC in the SBRT group than for those with NSCLC in the standard-of-care group (10·0 months [7·2-not reached] vs 2·2 months [95% CI 2·0-4·5]; HR 0·41, 95% CI 0·22-0·75; p=0·0039), but no difference was found for patients with breast cancer (4·4 months [2·5-8·7] vs 4·2 months [1·8-5·5]; 0·78, 0·43-1·43; p=0·43). Grade 2 or worse adverse events occurred in 21 (41%) patients in the standard-of-care group and 34 (62%) patients in the SBRT group. Nine (16%) patients in the SBRT group had grade 2 or worse toxicities related to SBRT, including gastrointestinal reflux disease, pain exacerbation, radiation pneumonitis, brachial plexopathy, and low blood counts.

INTERPRETATION

The trial showed that progression-free survival was increased in the SBRT plus standard-of-care group compared with standard of care only. Oligoprogression in patients with metastatic NSCLC could be effectively treated with SBRT plus standard of care, leading to more than a four-times increase in progression-free survival compared with standard of care only. By contrast, no benefit was observed in patients with oligoprogressive breast cancer. Further studies to validate these findings and understand the differential benefits are warranted.

FUNDING

National Cancer Institute.

Clinical and Dosimetric Risk Factors Associated With Radiation-Induced Lung Toxicities After Multiple Courses of Lung Stereotactic Body Radiation Therapy

Purpose

Data are limited on radiation-induced lung toxicities (RILT) after multiple courses of lung stereotactic body radiation therapy (SBRT). We herein analyze a large cohort of patients to explore the clinical and dosimetric risk factors associated with RILT in such settings.

Methods and Materials

A single institutional database of patients treated with multiple courses of lung SBRT between January 2014 and December 2019 was analyzed. Grade 2 or higher (G2+) RILT after the last course of SBRT was the primary endpoint. Composite plans were generated with advanced algorithms including deformable registration and equivalent dose adjustment. Logistic regression analyses were performed to examine correlations between patient or treatment factors including dosimetry and G2+ RILT. Risk stratification of patients and lung constraints based on acceptable normal tissue complication probability were calculated based on risk factors identified.

Results

Among 110 eligible patients (56 female and 54 male), there were 64 synchronous (58.2%; defined as 2 courses of SBRT delivered within 30 days) and 46 metachronous (41.8%) courses of SBRT. The composite median lung V20, lung V5, and mean lung dose were 9.9% (interquartile range [IQR], 7.3%-12.4%), 32.2% (IQR, 25.5%-40.1%), and 7.0 Gy (IQR, 5.5 Gy-8.6 Gy), respectively. With a median follow-up of 21.1 months, 30 patients (27.3%) experienced G2+ RILT. Five patients (4.5%) developed G3 RILT, and 1 patient (0.9%) developed G4 RILT, and no patients developed G5 RILT. On multivariable regression analysis, female sex (odds ratio [OR], 4.35; 95% CI, 1.49%-14.3%; P = .01), synchronous SBRT (OR, 8.78; 95% CI, 2.27%-47.8%; P = .004), prior G2+ RILT (OR, 29.8; 95% CI, 2.93%-437%; P = .007) and higher composite lung V20 (OR, 1.18; 95% CI, 1.02%-1.38%; P = .030) were associated with significantly higher likelihood of G2+ RILT.

Conclusions

Our data suggest an acceptable incidence of G2+ RILT after multiple courses of lung SBRT. Female sex, synchronous SBRT, prior G2+ RILT, and higher composite lung V20 may be risk factors for G2+ RILT.

Stereotactic Body Radiation Therapy for Stage IIA to IIIA Inoperable Non-Small Cell Lung Cancer: A Phase 1 Dose-Escalation Trial

PURPOSE

Larger tumors are underrepresented in most prospective trials on stereotactic body radiation therapy (SBRT) for inoperable non-small cell lung cancer (NSCLC). We performed this phase 1 trial to specifically study the maximum tolerated dose (MTD) of SBRT for NSCLC >3 cm.

METHODS AND MATERIALS

A 3 + 3 dose-escalation design (cohort A) with an expansion cohort at the MTD (cohort B) was used. Patients with inoperable NSCLC >3 cm (T2-4) were eligible. Select ipsilateral hilar and single-station mediastinal nodes were permitted. The initial SBRT dose was 40 Gy in 5 fractions, with planned escalation to 50 and 60 Gy in 5 fractions. Adjuvant chemotherapy was mandatory for cohort A and optional for cohort B, but no patients in cohort B received chemotherapy. The primary endpoint was SBRT-related acute grade (G) 4+ or persistent G3 toxicities (Common Terminology Criteria for Adverse Events version 4.03). Secondary endpoints included local failure (LF), distant metastases, disease progression, and overall survival.

RESULTS

The median age was 80 years; tumor size was >3 cm and ≤5 cm in 20 (59%) and >5 cm in 14 patients (41%). In cohort A (n = 9), 3 patients treated to 50 Gy experienced G3 radiation pneumonitis (RP), thus defining the MTD. In the larger dose-expansion cohort B (n = 25), no radiation therapy-related G4+ toxicities and no G3 RP occurred; only 2 patients experienced G2 RP. The 2-year cumulative incidence of LF was 20.2%, distant failure was 34.7%, and disease progression was 54.4%. Two-year overall survival was 53%. A biologically effective dose (BED) <100 Gy was associated with higher LF (P = .006); advanced stage and higher neutrophil/lymphocyte ratio were associated with greater disease progression (both P = .004).

CONCLUSIONS

Fifty Gy in 5 fractions is the MTD for SBRT to tumors >3 cm. A higher BED is associated with fewer LFs even in larger tumors. Cohort B appears to have had less toxicity, possibly due to the omission of chemotherapy.

Multi-institutional analysis of aneuploidy and outcomes to chemoradiation and durvalumab in stage III non-small cell lung cancer

There is a need to identify predictive biomarkers to guide treatment strategies in stage III non-small cell lung cancer (NSCLCs). In this multi-institutional cohort of 197 patients with stage III NSCLC treated with concurrent chemoradiation (cCRT) and durvalumab consolidation, we identify that low tumor aneuploidy is independently associated with prolonged progression-free survival (HR 0.63; p=0.03) and overall survival (HR 0.50; p=0.03). Tumors with high aneuploidy had a significantly greater incidence of distant metastasis and shorter median distant-metastasis free survival (p=0.04 and p=0.048, respectively), but aneuploidy level did not associate with local-regional outcomes. Multiplexed immunofluorescence analysis in a cohort of NSCLC found increased intratumoral CD8-positive, PD-1-positive cells, double-positive PD-1 CD8 cells, and FOXP3-positive T-cell in low aneuploid tumors. Additionally, in a cohort of 101 patients treated with cCRT alone, tumor aneuploidy did not associate with disease outcomes. These data support the need for upfront treatment intensification strategies in stage III NSCLC patients with high aneuploid tumors and suggest that tumor aneuploidy is a promising predictive biomarker.

Tumor-Targeted Nonablative Radiation Promotes Solid Tumor CAR T-cell Therapy Efficacy

Infiltration of tumor by T cells is a prerequisite for successful immunotherapy of solid tumors. In this study, we investigate the influence of tumor-targeted radiation on chimeric antigen receptor (CAR) T-cell therapy tumor infiltration, accumulation, and efficacy in clinically relevant models of pleural mesothelioma and non-small cell lung cancers. We use a nonablative dose of tumor-targeted radiation prior to systemic administration of mesothelin-targeted CAR T cells to assess infiltration, proliferation, antitumor efficacy, and functional persistence of CAR T cells at primary and distant sites of tumor. A tumor-targeted, nonablative dose of radiation promotes early and high infiltration, proliferation, and functional persistence of CAR T cells. Tumor-targeted radiation promotes tumor-chemokine expression and chemokine-receptor expression in infiltrating T cells and results in a subpopulation of higher-intensity CAR-expressing T cells with high coexpression of chemokine receptors that further infiltrate distant sites of disease, enhancing CAR T-cell antitumor efficacy. Enhanced CAR T-cell efficacy is evident in models of both high-mesothelin-expressing mesothelioma and mixed-mesothelin-expressing lung cancer-two thoracic cancers for which radiotherapy is part of the standard of care. Our results strongly suggest that the use of tumor-targeted radiation prior to systemic administration of CAR T cells may substantially improve CAR T-cell therapy efficacy for solid tumors. Building on our observations, we describe a translational strategy of "sandwich" cell therapy for solid tumors that combines sequential metastatic site-targeted radiation and CAR T cells-a regional solution to overcome barriers to systemic delivery of CAR T cells.

The Impact of Co-Alterations on Outcomes after Local Therapy for Patients with KRAS-Mutant Lung Adenocarcinoma Brain Metastases

PURPOSE/OBJECTIVE(S)

Brain metastases are common in NSCLC with up to 25% of patients having brain metastases (BMs) at the time of diagnosis and 30% developing BMs during their disease course. KRAS is an oncogenic driver in approximately 25% of lung adenocarcinomas. Genomic alterations co-occurring with KRAS are associated with distinct biological landscapes which may influence prognosis. Herein, we sought to identify correlations between genomic profiles, intracranial progression free survival (iPFS), and overall survival (OS).

MATERIALS/METHODS

We retrospectively reviewed 156 patients with KRAS-mutant lung adenocarcinoma BM who underwent SRS for their BMs at MSKCC from 2010-2022. Each patient had at least one tumor sample profiled with MSK-IMPACT, a custom FDA-cleared next-generation sequencing. Mutations, copy number alterations, and fusions were filtered for driver alterations using OncoKB. Survival outcomes were calculated from date of MRI indicating metastatic brain disease.

RESULTS

Of the 156 patients, 80 patients presented with BMs at diagnosis whereas 76 developed BMs during their disease course, with a median 2 lines of therapy prior to BM diagnosis. The most common KRAS mutation was G12C (n = 64; 41%), G12V (n = 26, 17%), G12D (n = 17; 11%), and G12A (n = 11; 7%). The most frequently co-altered genes were TP53 (n = 71, 46%), STK11 (n = 51, 33%), CDKN2A (n = 27, 17%), KEAP1 (n = 17, 11%), and SMARCA4 (n = 10, 6%). The presence of a KEAP1 co-occurring alteration was associated with inferior iPFS (HR 1.95, 95% CI 1.05 - 3.59, p = 0.035) and the presence of SMARCA4 was also associated with inferior iPFS (HR 2.28, 95% CI 1.05 - 4.95, p = 0.038). The presence of an STK11 mutation was associated with worse OS (HR 1.57, 95% 1.01 - 2.43, p = 0.045). In a multi-variate clinico-genomic model, KEAP1 and STK11 co-occurring alterations remained significantly associated with iPFS. Patients with KEAP1-altered tumors had an increased incidence of intracranial regional progression. The 24-month cumulative incidence of regional progression amongst KEAP1-altered tumors was 57% (95% CI, 29%-77%) compared with 37% (95% CI, 29%-46%) among KEAP1-wildtype tumors (P = 0.041). Patients with CDKN2A-altered tumors had an increased incidence of leptomeningeal disease (LMD) as a form of intracranial progression. The 24-month cumulative incidence of LMD amongst CDKN2A-altered tumors was 11% (95% CI, 2.7%-27%) compared with 4.1% (95% CI, 1.5%-8.8%) among CDKN2A-wildtype tumors (P = 0.023).

CONCLUSION

In our cohort of molecularly profiled KRAS-mutant lung adenocarcinoma BM patients treated with SRS, we found that co-occurring KEAP1 and STK11 were significantly associated with worse iPFS. We also observed that CDKN2A co-altered tumors had an increased incidence of LMD. These findings have implications for future efforts to personalize brain metastasis management based on comprehensive genomic profiling.

Peripheral T-Cell Priming and Micrometastatic Disease Control with Metastasis-Directed Therapy: Multidimensional Immunogenomic Profiling of Oligometastatic Prostate Cancer in the EXTEND Trial

PURPOSE/OBJECTIVE(S)

Comprehensive metastasis-directed therapy (MDT) for oligometastatic prostate cancer extended progression-free survival (PFS) and time to new lesion formation in the intermittent hormone therapy (HT) basket of EXTEND. To better understand the mechanism of MDT benefit, we pooled the intermittent and continuous HT baskets of EXTEND and tested the hypothesis that adding MDT to HT would program systemic T-cells to control micrometastatic disease.

MATERIALS/METHODS

A total of 174 men were randomized to HT with or without MDT to up to 5 sites of metastases. HT was given for 6 months (intermittent basket, n = 87) or indefinitely (continuous basket, n = 87). Peripheral blood samples were drawn at enrollment, at the end of MDT, at 3 months follow-up (3 mo F/U), and at progression and then analyzed by flow cytometry, T-cell receptor (TCR)-β CDR3 variable region sequencing, multiplex cytokine profiling, and next-generation circulating tumor DNA (ctDNA) sequencing. TCR clonal expansion was determined using a published betabinomial model. Repertoire changes were assessed by Morisita's index, and dominant TCR repertoire motifs were characterized with ImmunoMap. Associations between blood markers and PFS were evaluated with Cox regression adjusted hazard ratios (aHR) accounting for randomization arm and stratifying for intermittent vs continuous HT.

RESULTS

Randomization to MDT+HT was associated with T-cell activation, proliferation, and clonal expansion. This response was first observed at end-MDT as upregulated expression of T-cell activation and inhibition markers (i.e., ICOS, Tim-3, and LAG-3) and increases in highly proliferative CD4+ and CD8+ Ki67hi T-cells (all P<0.05). TCR sequencing of 7,678,911 T-cells revealed that MDT+HT was associated with TCR clonal expansion, remodeling of the TCR repertoire, and changes in dominant TCR motifs at end-MDT and 3 mo F/U (all P<0.05). Observed T-cell priming could be driven by signaling networks of canonical T-cell stimulatory cytokines (IL-2, IL-12, and IL-15), which were upregulated at end-MDT and persisted at 3 mo F/U (all P<0.05). This modulation of T-cell phenotype, clonotype, and cytokine concentrations was not observed in the HT-monotherapy arm. At end-MDT, systemic T-cell responses were associated with improved PFS, most notably CD8+ T-cell expression of LAG-3 (aHR 0.22, 95% CI 0.03-0.91) and high TCR clonal expansion (aHR 0.13, 95% CI 0.02-0.52). High ctDNA burden at end-MDT correlated with worse PFS (aHR 1.41, 95% CI 1.04-2.54), as did CD8+ T-cell expression of inhibitory receptor TIGIT at 3 mo F/U (aHR 1.03, 95% CI 1.01-1.06).

CONCLUSION

The addition of MDT to HT induced systemic T-cell activation and expansion, which was not observed in the HT-only arm. This systemic immune response was independently associated with improved PFS. In addition to cytoreduction of macroscopic disease, MDT-induced immune education may be an important complementary mechanism of micrometastatic control in oligometastatic prostate cancer.

Phase II Study of Hemithoracic Intensity-Modulated Pleural Radiation Therapy (IMPRINT) for Patients with Pleural Metastases from Thymic Malignancies

PURPOSE/OBJECTIVE(S)

Pleural metastases are common sites for recurrence and progression in patients with thymic malignancies. The management of pleural metastases typically involves surgical resection with or without neoadjuvant or adjuvant systemic therapy. After surgical resection of pleural metastases, the 5-year progression-free survival (PFS) rate is about 29-45%. While radiation therapy (RT) is standardly used in the management of locally-advanced thymic malignancies, the role of RT in patients with pleural metastases in unclear. Intensity-modulated pleural radiation therapy (IMPRINT) is a RT technique currently being used to treat malignant pleural mesothelioma (MPM) patients with 2 intact lungs at centers that specialize in MPM treatment. This IMPRINT technique can potentially be extrapolated to thymic patients with pleural metastases. Because the risk of toxicity is of greater concern for thymic patients given their overall relatively favorable prognosis, the rate of toxicity, particularly radiation pneumonitis, needs to be established in the thymic patient population.

MATERIALS/METHODS

This is a single-arm, single institution Phase II study of hemithoracic IMPRINT for patients with pleural metastases from thymic malignancies. The primary endpoint of this study is grade 3 or higher radiation pneumonitis within 4 months of completing RT. Secondary endpoints include any toxicity, progression-free survival, patterns of failure and overall survival. Patients must have a pathologically confirmed diagnosis of a thymic malignancy with radiologic or pathologic evidence of pleural metastases. Thymoma or thymic carcinoma are allowed. Patients may have de novo stage IVA disease or recurrent disease in the pleura. There must be no evidence of extrathoracic metastatic disease or contralateral pleural/pericardial disease. Surgical resection of the pleural nodules (ex: pleurectomy/decortication, debulking/metastasectomy) are allowed. Extrapleural pneumonectomy is not allowed. Patients are excluded if they have undergone prior thoracic radiation therapy preventing hemithoracic pleural IMRT, whereas prior thymic bed radiation and/or prior pleural SBRT are allowed. RT will be administered to the ipsilateral pleura to 50.4 Gy in 28 fractions. An optional dose-painting boost to gross disease up to 60 Gy while respecting normal tissue constraints is allowed. Patients can be treated with photon or proton therapy. Simulation, contouring and RT planning guidelines have been developed. Patients will be followed per protocol at regular intervals for at least 12 months following RT. The expected accrual is 36 patients over 4 years. Further information can be found on clinicaltrials.gov (NCT05354570).

RESULTS

To be determined.

CONCLUSION

To be determined.

Inpatient Simulation Resource Utilization for Inpatient Radiation Oncology Consults

PURPOSE/OBJECTIVE(S)

Previous data have shown that inpatient radiation oncology consult services result in high-value care, with decreased length of stay, adoption and delivery of shorter fractionation schedules, and lower hospital costs. As such, institutions are increasingly creating inpatient radiation oncology services, although little is known about the allocation of limited resources for patients who may have limited prognosis, complex simulation requirements, and may have difficulty tolerating treatment. Thus, we sought to examine the utilization of simulation appointments for inpatient emergencies.

MATERIALS/METHODS

At our institution, inpatient consults are placed to a specialized inpatient palliative radiation oncology service, consisting of radiation oncologists specialized in metastatic and palliative RT, dedicated advanced practitioners, and nurses who specifically assess patients for medical appropriateness prior to simulation, including changes in disposition, medical stability, and adequate premedication. Electronic health record data was used to explore utilization trends of a single-institution inpatient radiation oncology consult service in 2020. Data regarding the nature and timing of consults, subsequent simulations and treatments, and patient outcomes including 14-day mortality and 30-day mortality from radiation (RT) start were assessed. Descriptive statistics are presented.

RESULTS

From 1/1/2020-12/31/2020, 1557 consults were placed. These consults led to 220 (14.1%) inpatient simulations. Of these planned simulations, 210 (95.5%) simulations occurred (of which 10 [4.8%] were rescheduled and eventually completed) and 179 (85.2%) completed treatment. Of 169 with mortality data available, 16 (9.5%) died within 14 days of RT start, and 41 (24.5%) died within 30 days of RT start. Of those with scheduling data (N = 193), 122 were same-day simulations (63.2%), and 507 (93.8%) occurred within 7 days or fewer.

CONCLUSION

Of 1557 inpatient consultations in one year, with appropriate metastatic and palliative experience, only a minority of consultations required inpatient simulation (14.1%). With appropriate nursing assessment, over 95% were able to complete simulation, with nearly two-thirds completing simulation on the same day, and nearly all patients completing simulation within a week of consultation. Most of these patients completed treatment and survived 30 days from treatment start. Thus, with highly specialized radiation oncologist clinical judgment in conjunction with appropriate nursing assessment prior to simulation scheduling, patients booked for simulation represent high-value utilization of resources.

Clinical Sequalae of Initial Insurance Denials in a Large Academic Radiation Oncology Center

PURPOSE/OBJECTIVE(S)

The objective of this study is to investigate the clinical sequalae of initial radiation oncology insurance denials. The hypothesis is that while the majority of initial insurance case denials are ultimately overturned, there are potential clinical implications to these initial denials.

MATERIALS/METHODS

Data were extracted from an institutional registry of patient cases initially denied authorization by their insurers from January 2022 to December 2022. Chi-Square tests using statistical software were employed.

RESULTS

Two hundred six cases from November 2021 to December 2022 were identified. The majority (n = 199 [96.6%]) of insurers were commercial payers, while 7 (3.4%) were Medicare/Medicare Advantage. 161 (78.1%) patients were <65 years of age, and 45 (21.8%) 65 or older. One hundred forty-one (68.4%) cases were metastatic, 60 (29.1%) definitive, and 5 (2.4%) were recurrent. Of the 206 cases, 127 (61.6%) cases were ultimately successful in authorization of the ordered treatment without any change to the requested treatment technique or prescription dose after P2P (Peer to Peer review), second-level appeal, comparison plan submission, employer request, insurance carrier change, and/or external appeal, and 56 (27.2%) cases were authorized though with insurer-requested modification to radiation treatment technique and/or prescription dose. Of 21 cases with a requested change in prescription dose, the median decrease in biologically effective dose (BED) was 24 Gy (range: 2.3-51). Of 58 cases with requested change in RT technique, 20 (34.5%) changed from IMRT to 3D-CRT, 16 (27.6%) SBRT to 3D, 15 (25.9%) SBRT to IMRT, 6 (10.3%) SBRT to 2D, and 1 (1.7%) 3D-CRT to 2D. 19 (9.2%) cases remained unauthorized by the insurer but proceeded with treatment via departmental administrative clearance. Of 196 cases which went on to treatment, 72 (36.7%) cases were delayed for a mean of 7.8 days and median of 5 days (range: 1-49). P2P was performed by the treating radiation oncologist in 169 (82.0%) cases, of which 78 (46.1%) were successful in authorization of the ordered treatment. Of the 91 unsuccessful cases, 62 (68.1%) second-level appeals were performed, of which 39 (62.9%) were successful in overturning denied authorization. Of the 23 cases not authorized either through P2P or second-level appeal, 3 (13.0%) cases were successful in authorization of the requested treatment via employer request, external appeal through an independent review organization, or insurance carrier change.

CONCLUSION

Our institutional analysis suggests that while the majority of initial insurance case denials are ultimately overturned without any change to the requested treatment technique or prescription dose through a number of requests made by the insurer to the radiation oncologist, there are clinical implications with a significant percentage of case denials leading to treatment delays, decrease in prescription BED, and less conformal treatment technique.

Prospective, Cell-Free Circulating Tumor DNA (ctDNA) Profiling in Locally Advanced Lung Cancer Treated with Chemoradiation

PURPOSE/OBJECTIVE(S)

Liquid biopsy for cell-free circulating tumor DNA (ctDNA) allows for non-invasive, comprehensive genomic profiling. We explored the utility prospective liquid biopsy for (ctDNA) in among non-small cell lung cancer (NSCLC) patients treated with definitive chemoradiation.

MATERIALS/METHODS

This prospective clinical cohort consists of unresectable, locally advanced NSCLC patients who had liquid biopsy testing prior to initiation of cancer therapy. Liquid biopsy testing was performed using a next-generation sequencing assay (MSK-ACCESS) which includes 129 genes and paired white blood cell sequencing. An FDA-recognized database (OncoKB) was utilized to classify alterations associated with radiation resistance (including KEAP1, NFE2L2, STK11, and PIK3CA) and radiation sensitivity (including ATM, ATR, BRCA1/2, ARID1A, MLH1 and other DNA Damage Repair Pathway alterations). We evaluated progression-free survival (PFS) from the completion of chemoradiation using the Log-rank test.

RESULTS

Among 25 patients with prospective ctDNA testing prior to therapy initiation, 17 patients had stage III disease (68%), 8 patients had stage II disease (32%), 18 patients had adenocarcinoma (72%), 7 patients had squamous cell carcinoma (28%), and 23 (92%) were former or current smokers. The median radiation dose was 60 Gy in 30 fractions (range: 55 to 66 Gy in 20 to 33 fractions). 76% of patients (n = 18) had one or more alterations detected (median: 3 alterations, range: 1 - 8) including genomic markers of radiation response in 2 patients in BRCA1/2 (n = 2) and radiation resistance in 1 patient in KEAP1. The most common driver alteration detected was KRAS in 24% of the cohort (n = 6). Among patients with baseline detectable ctDNA, the median PFS was 21.3 months and was not reached among patients without baseline ctDNA detection (HR 4.54, p = 0.04).

CONCLUSION

Using an institutional assay, the presence of baseline cell-free ctDNA appeared prognostic in patients with unresectable, locally advanced NSCLC treated with definitive chemoradiation. We also detected driver alterations and potential markers of radiation resistance and response using ctDNA testing. Prospective cell-free ctDNA profiling may offer pathways to therapy personalization among patients with locally advanced unresectable lung cancer.

Addition of Metastasis-Directed Therapy to Standard of Care Systemic Therapy for Oligometastatic Breast Cancer (EXTEND): A Multicenter, Randomized Phase II Trial

PURPOSE/OBJECTIVE(S)

Prior retrospective and prospective evidence have suggested a potential survival benefit of adding metastasis-directed therapy (MDT) to standard of care systemic therapy for oligometastatic breast cancer. This has led to the increased utilization of MDT in this setting despite the lack of randomized evidence to support this approach. Furthermore, the recent presentation of NRG-BR002 has questioned the value of MDT. Thus, we evaluated whether the addition of MDT to systemic therapy improves PFS in oligometastatic breast cancer.

MATERIALS/METHODS

EXTEND (NCT03599765) is a phase II randomized basket trial for multiple solid tumors testing whether the addition of MDT improves PFS. The primary endpoint was pre-specified to be independently assessed and reported for the breast basket when a minimum of 6 months of follow-up had been reached. Patients with ≤5 metastases were randomized to standard of care systemic therapy with or without MDT. The choice of systemic therapy was at the discretion of the treating medical oncologist. Number of metastatic lesions and prior lines of systemic therapy for metastatic disease were used as stratification variables pre-randomization. The primary endpoint was progression-free survival (PFS) defined as time to randomization to date of clinical or radiographic progression or death. The study was designed to have 80% power to detect an improvement in median PFS from 18 to 36 months, with a type I error of 0.1.

RESULTS

Between September 2018 to July 2022, 43 patients were randomized. 22 patients were assigned to the MDT arm, and 21 patients to the no MDT arm. Three patients were not evaluable. The MDT arm patients were older vs the no-MDT arm patients (median 61.5 years vs 48 years, p = 0.01). Otherwise, the arms were well-balanced. Overall, 8 patients had triple negative disease (18.6%), and 12 patients (30%) had de novo metastatic disease. Of those patients with de novo presentation randomized to MDT, all except one had the primary tumor treated with surgery and radiation. At a median follow-up of 19.4 months, 20 events were observed. Among the 40 evaluable patients, there were 5 deaths (3 in the MDT arm and 2 in the no MDT arm). There was no difference in PFS between the MDT and no MDT arms (median 15.6 v 24.9 months, p = 0.66). Similarly, there was no difference in the secondary endpoint of time to new metastatic lesion appearance between the MDT and no MDT arms (median 15.6 months vs not reached, p = 0.09). Two grade 3 toxicities were observed in the MDT arm, and 1 in the no MDT arm. Further analysis of correlative translational biomarkers, including immune markers and ctDNA, are ongoing.

CONCLUSION

The addition of MDT to standard of care systemic therapy did not improve PFS or time to new metastatic lesion in patients with oligometastatic breast cancer. This data coupled with the recently presented NRG-BR002 results, suggests there is no benefit to MDT in an otherwise unselected oligometastatic breast cancer population.

Harnessing Electronic Patient-Reported Outcomes (ePRO) in Routine Care to Promote Clinical Trial Enrollment: A Randomized Study

PURPOSE/OBJECTIVE(S)

Only approximately 5% of adult cancer patients participate in clinical trials. While collection of patient-reported outcomes (PRO) is now routine in clinical trials, their role in actively improving care is evolving, particularly in radiation oncology. At our single multi-site institution, weekly electronic patient reported outcomes (ePRO) questionnaires regarding acute toxicity are routinely sent to all patients undergoing breast radiation We hypothesized that using ePROs to prompt recruitment to a clinical trial assessing a supportive intervention would increase enrollment.

MATERIALS/METHODS

An automated weekly query of ePRO survey responses was generated to identify patients with moderate or greater fatigue, the primary eligibility criterion for an ongoing randomized clinical trial testing an integrative medicine intervention. 23 radiation oncologists treating breast cancer were randomized to have their patients potentially eligible by ePRO receive a direct portal message about the trial, or to usual care (physician-based referral). Physician randomization was stratified by patient caseload and assigned in a 1:1 ratio. Secondarily, every other patient in the portal message group was assigned to receive the message either from their radiation oncologist or integrative medicine. Statistical analysis included two-sample, two-sided proportion tests.

RESULTS

From September 5, 2022, to December 19, 2022, among 776 patients completing ePROs during radiation treatment, 252 patients (32%) screened positive for fatigue. Of those who screened positive, 135 were randomized to the ePRO-prompted portal message group and 117 to the usual care group (physician-based referral). Among patients in the portal message group, 52 responded (39%) and 27 enrolled (20%), compared to 1 patient referred (0.8%) and 0 enrolled with physician-based referral alone (p < 0.001). In the portal message group, there were 21 responses (30%) and 12 enrollments (17%) among those messaged by their radiation oncologist, compared to 31 responses (48%) and 15 enrollments (23%) among those messaged by integrative medicine. When evaluating the source of the portal message, there was a significant difference in response rate favoring integrative medicine (p = 0.03), but no difference in enrollments (p = 0.39).

CONCLUSION

Utilization of ePROs to prompt recruitment to a trial testing a symptom intervention resulted in increased enrollment compared to standard physician-based referral, suggesting a promising new role for ePROs. Importantly, messaging from the supportive care service directly did not result in a difference in enrollments and may help reduce oncology physician-level barriers to studies testing supportive interventions. Future directions should investigate this method to reduce disparities in patients enrolling on clinical trials and facilitate access to symptom support services in routine cancer care.

Stereotactic body radiation therapy for sarcoma pulmonary metastases

BACKGROUND/PURPOSE

Stereotactic body radiation therapy (SBRT) is standard for patients with inoperable early-stage NSCLC. We hypothesized that SBRT for sarcoma pulmonary metastases would achieve high rates of local control with acceptable toxicity and that patients with oligometastatic disease may achieve prolonged survival following SBRT.

MATERIALS/METHODS

This retrospective review included consecutive patients at our institution treated with SBRT for sarcoma pulmonary metastases. Cumulative incidence of local failure (LF) was estimated using a competing risks framework.

RESULTS

We identified 66 patients treated to 95 pulmonary metastases with SBRT. The median follow-up from the time of SBRT was 36 months (95% CI 34 - 53 months). The cumulative incidence of LF at 12 and 24 months was 3.1% (95% CI 0.9 - 10.6%) and 7.4% (95% CI 4.0% - 13.9%), respectively. The 12- and 24-month overall survival was 74% (95% CI 64 - 86%) and 49% (38 - 63%), respectively. Oligometastatic disease, intrathoracic only disease, and performance status were associated with improved survival on univariable analysis. Three patients had grade 2 pneumonitis, and one patient had grade 2 esophagitis. No patients had ≥ grade 3+ toxicities.

CONCLUSION

To the best of our knowledge, this is the largest series of patients treated with SBRT for pulmonary sarcoma metastases. We observed that SBRT offers an effective alternative to surgical resection with excellent local control and low proportions of toxicity.

AI Serial Image Prediction of Progression-Free Survival (PFS) for Locally Advanced Non-Small Cell Lung Cancer (LA-NSCLC) Patients Treated with Chemoradiation (CRT) and Durvalumab Consolidation

PURPOSE/OBJECTIVE(S)

Patient outcomes with definitive CRT for LA-NSCLC remain poor, with no imaging biomarkers to predict benefit. Hence, we developed a serial image AI model using paired planning CT (pCT) and first week cone-beam CT (CBCT) to predict PFS and measured AI model fairness defined as the bias in the classification with respect to gender as a protected attribute.

MATERIALS/METHODS

Sixty-four consecutive patients with LA-NSCLC treated with concurrent CRT to 60 Gy in 30 fractions and durvalumab consolidation were analyzed. Three prediction models were created. A previously developed AI image foundation model [1] was pre-trained with unlabeled 6,402 3D CT scans sourced from institutional and the Cancer Imaging Archive and modified to predict PFS as a binarized outcome (high PFS > 6 months and low PFS < 6 months) using pCT scans. Serial image AI model was created by adding the first week CBCT scan. The third model measured tumor growth rate (TGR) as relative change in tumor and nodal volume from pCT to CBCT derived using a different published AI model [2]. Association with PFS using univariable and multivariable Cox regression after adjusting for age, gender, planning tumor volume, and smoking status were measured using TGR and the two AI model predictions using a cutoff of > 50% probability for low PFS. AI model fairness metrics area under receiver operating curve (AUROC), precision, sensitivity, and specificity were computed.

RESULTS

TGR was not associated with PFS on univariate (Hazard ratio [HR] of 1.515, 95% confidence interval [CI] of 0.32 to 7.26, p = 0.60) or multivariate analysis (HR: 1.58, 95% CI: 0.32 to 7.80, p = 0.58) and resulted in a Harrell's C-index of 54.7%. The serial image AI model prediction was associated with PFS in both univariable (HR: 2.12, 95% CI: 1.02 to 4.40, p = 0.045) and multivariable analysis (HR 2.39, 95% CI of 1.09 to 5.25, p = 0.029), and a C-index of 62.5%. The pCT AI model was associated with PFS in univariate (HR 2.06, 95% CI of 1.06 to 4.01, p = 0.034) but not in multivariable analysis (HR 1.89, 95% CI of 0.93 to 3.87, p = 0.08), and a C-index of 59.9%. The serial image AI model reduced the parity in classification compared to pCT AI model indicating higher fairness (Table I).

CONCLUSION

The multi-image AI model predicted PFS with slightly higher accuracy and resulted in higher fairness than the pCT AI model. These results underscore the potential for incorporating multi-imaging biomarkers to predict treatment response.

A Novel FDG PET and Mean Lung Dose Model to Identify Stage III NSCLC Patients at High Risk of Developing Early Radiation Pneumonitis

PURPOSE/OBJECTIVE(S)

Early radiation pneumonitis (RPEarly) is a primary reason for the premature discontinuation of durvalumab consolidation and can lead to poor survival in patients with stage III non-small cell lung cancer (NSCLC). Currently, there are no RP risk models specifically tested for RPEarly. Here, we tested the applicability of published RP models for predicting RPEarly and explored the value of integrating pretreatment FDG-PET parameters.

MATERIALS/METHODS

The cohort consisted of all 178 LA-NSCLC patients treated with concurrent chemoradiation (cCRT) and durvalumab between May 2017 and December 2021. RPEarly was defined as RP occurring within three months of cCRT completion; late RP (RPLate) was defined as any later occurring RP. The three published RP models analyzed included: 1) Mean lung dose (MLD), 2) MLD, age, pulmonary comorbidity, smoking status, and tumor location, and 3) MLD, age and pulmonary comorbidity. In addition, pretreatment FDG PET-CT scans were used to calculate SUV parameters from auto-segmented normal lung contours: 10th- and 90th percentile (SUVP10, SUVP90), maximum, mean (SUVmean), minimum, and standard deviation. The RP models were fit to RPEarly, RPLate, and RPEarly+Late in the 178 patients. To assess the association between FDG PET parameters and RP unbiasedly, the cohort was then randomly split, but enforcing similar RP rates, into a two-thirds derivation and a one-third validation subset. Model performance was assessed by AUC, p-values and the Hosmer-Lemeshow test (pHL; ideally ∼0.50).

RESULTS

The rates of RPEarly, RPLate, and RPEarly+Late were 12%, 11%, and 23%, respectively (corresponding to 21, 20, and 41 events). Only the MLD model significantly predicted RPEarly (AUC = 0.70; p = 0.04; pHL = 0.84); none of the three models predicted RPLate or RPEarly+Late. Among the FDG PET parameters, SUVP10, SUVP90 and SUVmean predicted RPEarly with similar performance (AUC = 0.69-0.73; p = 0.005-0.01; pHL = 0.68-0.72), and, therefore, bivariate models were built between MLD and each of SUVP10, SUVP90 and SUVmean. Only the MLD + SUVP90 model generalized in the validation subset (AUC = 0.63; p = 0.03; pHL = 0.89) and was thus deemed the final model for RPEarly. A final re-fitting of all model coefficients to the whole cohort indicated improvement over using the published MLD alone model (AUC = 0.75 vs. 0.70; p-value = 0.0006 vs. 0.04; pHL = 0.67 vs. 0.84). Risk of RPEarly is thus estimated as: RPEarly = 1/(1 = e-x); x = -5.79 + (1.57*MLD) + (0.14* SUVP90).

CONCLUSION

Patients at risk for RPEarly can be accurately identified prior to treatment by combining a re-fitted version of the published Mean Lung Dose model and pre-treatment FDG PET SUVP90 of the normal lung. This refined model can be used to identify patients with an exacerbated risk for premature durvalumab discontinuation due to RPEarly and could allow for interventions and/or the generation of "RPEarly sparing" treatment plans to improve overall treatment outcomes.

Disparities in Stage at Presentation among Hispanic and Latinx Patients with Non-Small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

Hispanic and Latinx people in the United States comprise 19% of the population and are the fastest-growing ethnic group. However, prior studies in non-small cell lung cancer (NSCLC) often analyze these diverse communities in aggregate. We aimed to identify differences in NSCLC stage at diagnosis in the US population, with a particular focus on disaggregated Hispanic populations.

MATERIALS/METHODS

Data from the National Cancer Database (NCDB) from 2004 to 2018 were used to identify patients with primary NSCLC. Individuals were disaggregated by racial and ethnic subgroup and Hispanic country of origin. Ordinal logistic regression adjusting for age, facility type, income, educational attainment, comorbidity index, insurance, and year of diagnosis was used to create adjusted odds ratios (aORs), with higher odds representing diagnosis at later-stage NSCLC.

RESULTS

Out of 1,773,177 patients with NSCLC, 50,512 were Hispanic/Latinx (2.8%). Hispanic patients were less likely to be insured (χ2 P<0.001) and were more likely to live in lower-income ZIP codes (χ2 P<0.001). Hispanic patients were more likely to be diagnosed with metastatic disease compared to non-Hispanic White (NHW) patients: 47% for Hispanic Black (HB), 46% Hispanic White (HW), and 44.3% of Hispanic other (HO) patients vs. 39.1% of NHW patients (aORs for later-stage disease with NHW as reference: HW 1.23, HB 1.26, HO 1.14, P<0.001 for all). Upon disaggregation by country of origin, 51.4% of Mexican, 41.7% of Puerto Rican, 44.6% of Cuban, 50.8% of South or Central American, 48.4% of Dominican, and 45.6% of Other Hispanic patients were diagnosed with metastatic disease, compared with 39.1% of NHW patients. Conversely, 20.2% of Mexican, 26.9% of Puerto Rican, 24.2% of Cuban, 22.5% of South or Central American, 23.7% of Dominican, and 24.5% of Other Hispanic patients were diagnosed with stage I disease, compared with 30.0% of NHW patients. On multivariable analysis, all Hispanic groups were more likely to present with later-stage NSCLC than NHW patients, with the greatest odds for Mexican patients (aOR 1.45, P<0.001).

CONCLUSION

Hispanic/Latinx patients with non-small cell lung cancer were more likely to be diagnosed with more advanced disease compared with non-Hispanic White patients. Disparities persisted upon disaggregation by both race and country of origin, with over half of Mexican patients with metastatic disease at diagnosis. Disparities amongst Hispanic groups by race and by country of origin highlight the shortcomings of treating these groups as a monolith and underscore the need for disaggregated research and targeted interventions. Further work should explore differences in exposures, behaviors, and access to care that may underlie these disparities.

ctDNA-based detection of molecular residual disease in stage I-III non-small cell lung cancer patients treated with definitive radiotherapy

Background

Sensitive and reliable biomarkers for early detection of recurrence are needed to improve post-definitive radiation risk stratification, disease management, and outcomes for patients with unresectable early-stage or locally advanced non-small cell lung cancer (NSCLC) who are treated with definitive radiation therapy (RT). This prospective, multistate single-center, cohort study investigated the association of circulating tumor DNA (ctDNA) status with recurrence in patients with unresectable stage I-III NSCLC who underwent definitive RT.

Methods

A total of 70 serial plasma samples from 17 NSCLC patients were collected before, during, and after treatment. A personalized, tumor-informed ctDNA assay was used to track a set of up to 16 somatic, single nucleotide variants in the associated patient's plasma samples.

Results

Pre-treatment ctDNA detection rate was 82% (14/17) and varied based on histology and stage. ctDNA was detected in 35% (6/17) of patients at the first post-RT timepoint (median of 1.66 months following the completion of RT), all of whom subsequently developed clinical progression. At this first post-RT time point, patients with ctDNA-positivity had significantly worse progression-free survival (PFS) [hazard ratio (HR): 24.2, p=0.004], and ctDNA-positivity was the only significant prognostic factor associated with PFS (HR: 13.4, p=0.02) in a multivariate analysis. All patients who developed clinical recurrence had detectable ctDNA with an average lead time over radiographic progression of 5.4 months, and post-RT ctDNA positivity was significantly associated with poor PFS (p<0.0001).

Conclusion

Personalized, longitudinal ctDNA monitoring can detect recurrence early in patients with unresectable NSCLC patients undergoing curative radiation and potentially risk-stratify patients who might benefit most from treatment intensification.

Treatment of Oligometastatic Non-Small Cell Lung Cancer: An ASTRO/ESTRO Clinical Practice Guideline

PURPOSE

This joint guideline by American Society for Radiation Oncology (ASTRO) and the European Society for Radiotherapy and Oncology (ESTRO) was initiated to review evidence and provide recommendations regarding the use of local therapy in the management of extracranial oligometastatic non-small cell lung cancer (NSCLC). Local therapy is defined as the comprehensive treatment of all known cancer-primary tumor, regional nodal metastases, and metastases-with definitive intent.

METHODS

ASTRO and ESTRO convened a task force to address 5 key questions focused on the use of local (radiation, surgery, other ablative methods) and systemic therapy in the management of oligometastatic NSCLC. The questions address clinical scenarios for using local therapy, sequencing and timing when integrating local with systemic therapies, radiation techniques critical for oligometastatic disease targeting and treatment delivery, and the role of local therapy for oligoprogression or recurrent disease. Recommendations were based on a systematic literature review and created using ASTRO guidelines methodology.

RESULTS

Based on the lack of significant randomized phase 3 trials, a patient-centered, multidisciplinary approach was strongly recommended for all decision-making regarding potential treatment. Integration of definitive local therapy was only relevant if technically feasible and clinically safe to all disease sites, defined as 5 or fewer distinct sites. Conditional recommendations were given for definitive local therapies in synchronous, metachronous, oligopersistent, and oligoprogressive conditions for extracranial disease. Radiation and surgery were the only primary definitive local therapy modalities recommended for use in the management of patients with oligometastatic disease, with indications provided for choosing one over the other. Sequencing recommendations were provided for systemic and local therapy integration. Finally, multiple recommendations were provided for the optimal technical use of hypofractionated radiation or stereotactic body radiation therapy as definitive local therapy, including dose and fractionation.

CONCLUSIONS

Presently, data regarding clinical benefits of local therapy on overall and other survival outcomes is still sparse for oligometastatic NSCLC. However, with rapidly evolving data being generated supporting local therapy in oligometastatic NSCLC, this guideline attempted to frame recommendations as a function of the quality of data available to make decisions in a multidisciplinary approach incorporating patient goals and tolerances.

Randomized Phase 2 Placebo-Controlled Trial of Nintedanib for the Treatment of Radiation Pneumonitis

PURPOSE

Radiation pneumonitis (RP) is the most common dose-limiting toxicity for thoracic radiation therapy. Nintedanib is used for the treatment of idiopathic pulmonary fibrosis, which shares pathophysiological pathways with the subacute phase of RP. Our goal was to investigate the efficacy and safety of nintedanib added to a prednisone taper compared with a prednisone taper alone in reducing pulmonary exacerbations in patients with grade 2 or higher (G2+) RP.

METHODS AND MATERIALS

In this phase 2, randomized, double-blinded, placebo-controlled trial, patients with newly diagnosed G2+ RP were randomized 1:1 to nintedanib or placebo in addition to a standard 8-week prednisone taper. The primary endpoint was freedom from pulmonary exacerbations at 1 year. Secondary endpoints included patient-reported outcomes and pulmonary function tests. Kaplan-Meier analysis was used to estimate the probability of freedom from pulmonary exacerbations. The study was closed early due to slow accrual.

RESULTS

Thirty-four patients were enrolled between October 2015 and February 2020. Of 30 evaluable patients, 18 were randomized to the experimental Arm A (nintedanib + prednisone taper) and 12 to the control Arm B (placebo + prednisone taper). Freedom from exacerbation at 1 year was 72% (confidence interval, 54%-96%) in Arm A and 40% (confidence interval, 20%-82%) in Arm B (1-sided, P = .037). In Arm A, there were 16 G2+ adverse events possibly or probably related to treatment compared with 5 in the placebo arm. There were 3 deaths during the study period in Arm A due to cardiac failure, progressive respiratory failure, and pulmonary embolism.

CONCLUSIONS

There was an improvement in pulmonary exacerbations by the addition of nintedanib to a prednisone taper. Further investigation is warranted for the use of nintedanib for the treatment of RP.

Impact of TMB/PD-L1 expression and pneumonitis on chemoradiation and durvalumab response in stage III NSCLC

Although concurrent chemoradiation (CRT) and durvalumab consolidation has become a standard treatment for stage III non-small cell lung cancer (NSCLC), clinicopathologic and genomic factors associated with its efficacy remain poorly characterized. Here, in a multi-institutional retrospective cohort study of 328 patients treated with CRT and durvalumab, we identify that very high PD-L1 tumor proportion score (TPS) expression ( ≥ 90%) and increased tumor mutational burden (TMB) are independently associated with prolonged disease control. Additionally, we identify the impact of pneumonitis and its timing on disease outcomes among patients who discontinue durvalumab: compared to patients who experienced early-onset pneumonitis ( < 3 months) leading to durvalumab discontinuation, patients with late-onset pneumonitis had a significantly longer PFS (12.7 months vs not reached; HR 0.24 [95% CI, 0.10 to 0.58]; P = 0.001) and overall survival (37.2 months vs not reached; HR 0.26 [95% CI, 0.09 to 0.79]; P = 0.017). These findings suggest that opportunities exist to improve outcomes in patients with lower PD-L1 and TMB levels, and those at highest risk for pneumonitis.

Clinicopathologic, Genomic, and Immunophenotypic Landscape of ATM Mutations in Non-Small Cell Lung Cancer

PURPOSE

ATM is the most commonly mutated DNA damage and repair gene in non-small cell lung cancer (NSCLC); however, limited characterization has been pursued.

EXPERIMENTAL DESIGN

Clinicopathologic, genomic, and treatment data were collected for 5,172 patients with NSCLC tumors which underwent genomic profiling. ATM IHC was performed on 182 NSCLCs with ATM mutations. Multiplexed immunofluorescence was performed on a subset of 535 samples to examine tumor-infiltrating immune cell subsets.

RESULTS

A total of 562 deleterious ATM mutations were identified in 9.7% of NSCLC samples. ATM-mutant (ATMMUT) NSCLC was significantly associated with female sex (P = 0.02), ever smoking status (P < 0.001), non-squamous histology (P = 0.004), and higher tumor mutational burden (DFCI, P < 0.0001; MSK, P < 0.0001) compared with ATM-wild-type (ATMWT) cases. Among 3,687 NSCLCs with comprehensive genomic profiling, co-occurring KRAS, STK11, and ARID2 oncogenic mutations were significantly enriched among ATMMUT NSCLCs (Q < 0.05), while TP53 and EGFR mutations were enriched in ATMWT NSCLCs. Among 182 ATMMUT samples with ATM IHC, tumors with nonsense, insertions/deletions, or splice site mutations were significantly more likely to display ATM loss by IHC (71.4% vs. 28.6%; P < 0.0001) compared with tumors with only predicted pathogenic missense mutations. Clinical outcomes to PD-(L)1 monotherapy (N = 1,522) and chemo-immunotherapy (N = 951) were similar between ATMMUT and ATMWT NSCLCs. Patients with concurrent ATM/TP53 mutations had significantly improved response rate and progression-free survival with PD-(L)1 monotherapy.

CONCLUSIONS

Deleterious ATM mutations defined a subset of NSCLC with unique clinicopathologic, genomic, and immunophenotypic features. Our data may serve as resource to guide interpretation of specific ATM mutations in NSCLC.

Genomic mapping of metastatic organotropism in lung adenocarcinoma

We analyzed 2,532 lung adenocarcinomas (LUAD) to identify the clinicopathological and genomic features associated with metastasis, metastatic burden, organotropism, and metastasis-free survival. Patients who develop metastasis are younger and male, with primary tumors enriched in micropapillary or solid histological subtypes and with a higher mutational burden, chromosomal instability, and fraction of genome doublings. Inactivation of TP53, SMARCA4, and CDKN2A are correlated with a site-specific shorter time to metastasis. The APOBEC mutational signature is more prevalent among metastases, particularly liver lesions. Analyses of matched specimens show that oncogenic and actionable alterations are frequently shared between primary tumors and metastases, whereas copy number alterations of unknown significance are more often private to metastases. Only 4% of metastases harbor therapeutically actionable alterations undetected in their matched primaries. Key clinicopathological and genomic alterations in our cohort were externally validated. In summary, our analysis highlights the complexity of clinicopathological features and tumor genomics in LUAD organotropism.

Abstract 6063: Genomic characterization of non-small cell lung cancer (NSCLC) brain metastasis (BM) patients identifies novel alterations associated with tropisms and disease progression

Intro: Half of all patients with NSCLC develop BM during their clinical course. While modern NSCLC-directed agents yield excellent systemic response, most patients require focal BM treatment. Prior reports of BM genomics have been limited by low numbers and a lack of matched specimens. Here, we report the largest cohort to date of molecularly-profiled NSCLC BM samples with comprehensive clinical follow-up.

Methods: Clinical data and outcomes for 244 patients with NSCLC and resected BM were identified. Samples were assessed using MSK-IMPACT, a custom tumor-normal next generation sequencing assay. 51 (20.9%) patients had matched primary site tissue, and 44 (18%) patients had matched tissue from another metastatic site or CSF. Genomic alterations were filtered for driver variants using OncoKB. Publicly available genomic data for NSCLC primary samples was used for comparison against the primary samples from our BM cohort.

Results: The most frequently altered genes in BM tumors were TP53 (72%), CDKN2A (34%), KRAS (31%), KEAP1 (26%), and EGFR (21%). CDKN2A was more frequently altered in BM samples compared to NSCLC primary lesions (34% vs 14%, p = 0.003). Additionally, cell cycle pathway alterations were enriched in BM (56% vs 31%, p = 0.002). BM samples also had a significantly higher fraction of genome altered (FGA) relative to primary samples (p &lt; 0.0001). We then compared primary samples from BM patients against primary samples from metastatic NSCLC patients without BM and primary samples from non-metastatic NSCLC patients. We found an enrichment of alterations in TP53 (68.6% vs 27.7%, p &lt; 0.0001), NKX2-1 (11.4% vs 1.7%, p = 0.006), SMARCA4 (11.4% vs 2.1%, p = 0.01), RB1 (11.4% vs 1.7%, p = 0.006), and FOXA1 (11.4% vs 0.9%, p = 0.001) in the primary samples from BM patients compared to non-metastatic patients. Next, we grouped patients based on CNS progression patterns and found that EGFR alterations were enriched in patients with leptomeningeal progression when compared to patients without progression (42% vs 18%, p = 0.03).

Conclusions: In our cohort of molecularly-profiled NSCLC BM, we found an enrichment of cell cycle pathway alterations and a higher FGA in BMs compared to their primary tumor controls. Additionally, several genes were enriched in the primary tissue of patients that developed BM compared to primary tissue from non-metastatic patients. EGFR alterations were enriched in patients who develop leptomeningeal disease (LMD). Our work herein characterizes the genomic profiles of NSCLC patients with BM and identifies specific genes enriched in the primary tissue of BM patients compared to primary tissue from both non-BM metastatic patients and non-metastatic patients. Finally, our finding that EGFR alterations were enriched in patients with LMD suggests specific biologic underpinnings driving patterns of CNS progression.

Citation Format: Henry Walch, Anna Skakodub, Kathryn R. Tringale, Harish N. Vasudevan, Jordan Eichholz, Daniel W. Kelly, Emily Lebow, Nelson S. Moss, Kenny Kwok Hei Yu, Bob T. Li, Boris Mueller, Atif Khan, Yao Yu, Simon Powell, Jorge S. Reis-Filho, Brandon S. Imber, Pedram Razavi, Daniel R. Gomez, Nikolaus Schultz, Luke R. Pike. Genomic characterization of non-small cell lung cancer (NSCLC) brain metastasis (BM) patients identifies novel alterations associated with tropisms and disease progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6063.

Characterization of Central Nervous System Clinico-Genomic Outcomes in ALK-Positive Non-Small Cell Lung Cancer Patients with Brain Metastases Treated with Alectinib

INTRODUCTION

Highly effective brain-penetrant ALK-targeted tyrosine kinase inhibitors (TKIs) have been developed for the management of NSCLC patients with brain metastases (BM). Local therapy (LT) such as SRS or therapeutic craniotomy is increasingly being deferred for such patients. Herein we report detailed patient- and lesion-level intracranial outcomes and co-mutational genomic profiles from a cohort of NSCLC patients with BM treated with alectinib, with or without LT.

METHODS

We retrospectively reviewed ALK fusion-positive NSCLC patients with BMs who received alectinib at the diagnosis of BM from 1/2012 and 5/2021. Outcome variables included intracranial progression-free survival (iPFS), overall survival (OS), duration of TKI therapy, and CNS response rates. Genomic characteristics from tumor specimens were assessed with MSK-IMPACT, a next-generation sequencing (NGS)-based genomic profiling assay.

RESULTS

A total of 38 patients with 114 CNS lesions were included. Twelve of these patients also received contemporaneous LT (SRS, WBRT, or surgical resection). Maximal BM diameter in the TKI + LT group was greater (p < 0.003) but despite this difference, iPFS (TKI only, HR 1.21, 95 % CI 0.51-2.89; p = 0.66) and OS (TKI only, HR 5.99, 95 % CI 0.77-46.6; p = 0.052) were similar between groups and trended towards more favorable outcomes with the addition of LT. SMARCA4 co-alterations were associated with inferior OS (HR 8.76, 1.74-44.2; p = 0.009).

CONCLUSIONS

Our study demonstrated that patients with ALK fusion-positive NSCLC treated with TKI + LT had larger BM and higher likelihood of pre-treatment neurologic symptoms. Despite these differences, iPFS was similar between groups. Results should be interpreted with caution as our study was limited by an underpowered sample size. SMARCA4 co-alterations were associated with inferior OS and these findings warrant further investigation.

Analysis of Tumor Mutational Burden, Progression-Free Survival, and Local-Regional Control in Patents with Locally Advanced Non-Small Cell Lung Cancer Treated With Chemoradiation and Durvalumab

IMPORTANCE

The addition of consolidative durvalumab to chemoradiation has improved disease control and survival in locally advanced non-small cell lung cancer (NSCLC). However, there remains a need to identify biomarkers for response to this therapy to allow for risk adaptation and personalization.

OBJECTIVES

To evaluate whether TMB or other variants associated with radiation response are also associated with outcomes following definitive chemoradiation and adjuvant durvalumab among patients with locally advanced unresectable NSCLC.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included consecutive patients with unresectable locally advanced NSCLC treated with chemoradiation and adjuvant durvalumab between November 2013 and March 2020 who had prospective comprehensive genomic profiling. This study was completed at a multisite tertiary cancer center. The median (IQR) follow-up time was 26 (21-36) months. Statistical analysis was conducted from April to October 2022.

EXPOSURES

Patients were grouped into TMB-high (≥10 mutations/megabase [mt/Mb]) and TMB-low (<10 mt/Mb) groups and were additionally evaluated by the presence of somatic alterations associated with radiation resistance (KEAP1/NFE2L2) or radiation sensitivity (DNA damage repair pathway).

MAIN OUTCOMES AND MEASURES

The primary outcomes were 24-month local-regional failure (LRF) and progression-free survival (PFS).

RESULTS

In this cohort study of 81 patients (46 [57%] male patients; median [range] age, 67 [45-85] years), 36 patients (44%) had TMB-high tumors (≥10 mt/Mb). Patients with TMB-high vs TMB-low tumors had markedly lower 24-month LRF (9% [95% CI, 0%-46%] vs 51% [95% CI, 36%-71%]; P = .001) and improved 24-month PFS (66% [95% CI, 54%-84%] vs 27% [95% CI, 13%-40%]; P = .003). The 24-month LRF was 52% (95% CI, 25%-84%) among patients with KEAP1/NFE2L2-altered tumors compared with 27% (95% CI, 17%-42%) among patients with KEAP1/NFE2L2-wildtype tumors (P = .05). On Cox analysis, only TMB status was associated with LRF (hazard ratio [HR], 0.17; 95% CI, 0.03-0.64; P = .02) and PFS (HR, 0.45; 95% CI, 0.21-0.90; P = .03). Histology, disease stage, Eastern Cooperative Oncology Group status, programmed cell death ligand 1 expression, and pathogenic KEAP1/NFE2L2, KRAS, and DNA damage repair pathway alterations were not significantly associated with LRF or PFS.

CONCLUSIONS AND RELEVANCE

In this cohort study, TMB-high status was associated with improved local-regional control and PFS after definitive chemoradiation and adjuvant durvalumab. TMB status may facilitate risk-adaptive radiation strategies in unresectable locally advanced NSCLC.

Benchmarking Outcomes for Molecularly Characterized Synchronous Oligometastatic Non-Small-Cell Lung Cancer Reveals EGFR Mutations to Be Associated With Longer Overall Survival

PURPOSE

Local consolidative therapy (LCT) for patients with synchronous oligometastatic non-small-cell lung cancer is an evolving treatment strategy, but outcomes following LCT stratified by genetic mutations have not been reported. We sought to identify genomic associations with overall survival (OS) and progression-free survival (PFS) for these patients.

METHODS

We identified all patients presenting between 2000 and 2017 with stage IV non-small-cell lung cancer and ≤ 3 synchronous metastatic sites. Patients were grouped according to mutational statuses. Primary outcomes included OS and PFS following initial diagnosis.

RESULTS

Of 194 included patients, 121 received comprehensive LCT to all sites of disease with either surgery or radiation. TP53 mutations were identified in 40 of 78 (55%), KRAS in 32 of 95 (34%), EGFR in 24 of 109 (22%), and STK11 in nine of 77 (12%). At median follow-up of 96 months, median OS and PFS were 26 (95% CI, 23 to 31) months and 11 (95% CI, 9 to 13) months, respectively. On multivariable analysis, patients with EGFR mutations had lower mortality risk (hazard ratio [HR], 0.53; 95% CI, 0.29 to 0.98; P = .044) compared with wild-type patients, and patients with STK11 mutations had higher risk of progression or mortality (HR, 2.32; 95% CI, 1.12 to 4.79; P = .023) compared with wild-type patients. TP53 and KRAS mutations were not associated with OS or PFS. Among 71 patients with known EGFR mutational status who received comprehensive LCT, EGFR mutations were associated with lower mortality compared with wild-type (HR, 0.45; 95% CI, 0.22 to 0.94; P = .032).

CONCLUSION

When compared with wild-type patients, those with EGFR and STK11 mutations had longer OS and shorter PFS, respectively. EGFR mutations were associated with longer OS among oligometastatic patients treated with comprehensive LCT in addition to systemic therapy.

Safety and efficacy of stereotactic body proton therapy for high-risk lung tumors

Purpose

Stereotactic body proton therapy (SBPT) is an emerging treatment strategy for lung tumors that aims to combine the excellent local control benefits of ultra-hypofractionation with the physical advantages of protons, which reduce the integral dose to organs at risk (OARs) compared to photons. To date, however, very little data delivering SBPT in 5 or fewer fractions to lung tumors have been reported. Given that photon stereotactic body radiation therapy can struggle to deliver ablative doses to high-risk tumors (i.e., central/ultra-central location, prior in-field radiation, tumor size >5 cm, or the presence of severe pulmonary comorbidities) while adhering to OAR dose constraints, we hypothesized that SBPT would be an effective alternative for patients with high-risk tumors.

Methods and Materials

Twenty-seven high-risk patients with 29 lung tumors treated with SBPT at the New York Proton Center between December 2019 and November 2022 were retrospectively identified. Patients were divided into three major subgroups: early-stage non-small cell lung cancer (NSCLC), locally recurrent NSCLC, and metastatic cancer from lung cancer or other histologies. Patient characteristics were reported using descriptive statistics, actuarial methods were used to quantify disease control rates, and toxicities were scored using CTCAE v 5.0.

Results

The most common high-risk indications for SBPT were central/ultra-central tumor location (69.0%), severe COPD (48.1%), reirradiation (44.4%), significant pulmonary fibrosis (22.2%), and large tumor size > 5 cm (18.5%). In total, 96.6% of tumors were fully covered by the prescription dose without compromising target coverage. Three-year actuarial rates of local control for early-stage NSCLC, locally recurrent NSCLC, and metastatic patients were 89%, 100%, and 43%, respectively. Three-year actuarial rates of regional control were 89%, 67%, and 86%. Three-year actuarial rates of distant metastasis-free survival were 79%, 100%, and 0%. Two patients (7.4%), both of whom had clinically significant baseline interstitial lung disease and pre-treatment continuous oxygen demand, experienced grade ≥2 pulmonary toxicity (1 grade 3, 1 grade 5). There were no acute or late grade ≥2 toxicities related to esophagitis, cardiac injury, airway injury, pulmonary fibrosis, bronchopulmonary hemorrhage or brachial plexopathy.

Conclusions

In the largest study of proton SBRT reported to date, SBPT has a favorable toxicity profile while being an effective approach for treating most high-risk tumors without requiring dose de-escalation or compromising tumor coverage and warrants further investigation.

Association of cardiac calcium burden with overall survival after radiotherapy for non-small cell lung cancer

Background and purpose

Coronary calcifications are associated with coronary artery disease in patients undergoing radiotherapy (RT) for non-small cell lung cancer (NSCLC). We quantified calcifications in the coronary arteries and aorta and investigated their relationship with overall survival (OS) in patients treated with definitive RT (Def-RT) or post-operative RT (PORT).

Materials and methods

We analyzed 263 NSCLC patients treated from 2004 to 2017. Calcium burden was ascertained with a Hounsfield unit (HU) cutoff of > 130 in addition to a deep learning (DL) plaque estimator. The HU cutoff volumes were defined for coronary arteries (Plaque_Coro) and coronary arteries and aorta combined (Plaque_Coro+Ao), while the DL estimator ranged from 0 (no plaque) to 3 (high plaque). Patient and treatment characteristics were explored for association with OS.

Results

The median Plaque_Coro and Plaque_Coro+Ao was 0.75 cm³ and 0.87 cm³ in the Def-RT group and 0.03 cm³ and 0.52 cm³ in the PORT group. The median DL estimator was 2 in both cohorts. In Def-RT, large Plaque_Coro (HR:1.11 (95%CI:1.04-1.19); p = 0.008), and Plaque_Coro+Ao (HR:1.06 (95%CI:1.02-1.11); p = 0.03), and poor Karnofsky Performance Status (HR: 0.97 (95%CI: 0.94-0.99); p = 0.03) were associated with worse OS. No relationship was identified between the plaque volumes and OS in PORT, or between the DL plaque estimator and OS in either Def-RT or PORT.

Conclusions

Coronary artery calcification assessed from RT planning CT scans was significantly associated with OS in patients who underwent Def-RT for NSCLC. This HU thresholding method can be straightforwardly implemented such that the role of calcifications can be further explored.

STK11 Inactivation Predicts Rapid Recurrence in Inoperable Early-Stage Non-Small-Cell Lung Cancer

PURPOSE

Molecular factors predicting relapse in early-stage non-small-cell lung cancer (ES-NSCLC) are poorly understood, especially in inoperable patients receiving radiotherapy (RT). In this study, we compared the genomic profiles of inoperable and operable ES-NSCLC.

MATERIALS AND METHODS

This retrospective study included 53 patients with nonsquamous ES-NSCLC (stage I-II) treated at a single institution (University of Chicago) with surgery (ie, operable; n = 30) or RT (ie, inoperable; n = 23) who underwent tumor genomic profiling. A second cohort of ES-NSCLC treated with RT (Stanford, n = 39) was included to power clinical analyses. Prognostic gene alterations were identified and correlated with clinical variables. The primary clinical end point was the correlation of prognostic genes with the cumulative incidence of relapse, disease-free survival, and overall survival (OS) in a pooled RT cohort from the two institutions (N = 62).

RESULTS

Although the surgery cohort exhibited lower rates of relapse, the RT cohort was highly enriched for somatic STK11 mutations (43% v 6.7%). Receiving supplemental oxygen (odds ratio [OR] = 5.5), 20+ pack-years of tobacco smoking (OR = 6.1), and Black race (OR = 4.3) were associated with increased frequency of STK11 mutations. In the pooled RT cohort (N = 62), STK11 mutation was strongly associated with inferior oncologic outcomes: 2-year incidence of relapse was 62% versus 20% and 2-year OS was 52% versus 85%, remaining independently prognostic on multivariable analyses (relapse: subdistribution hazard ratio = 4.0, P = .0041; disease-free survival: hazard ratio, 6.8, P = .0002; OS: hazard ratio, 6.0, P = .022). STK11 mutations were predominantly associated with distant failure, rather than local.

CONCLUSION

In this cohort of ES-NSCLC, STK11 inactivation was associated with poor oncologic outcomes after RT and demonstrated a novel association with clinical hypoxia, which may underlie its correlation with medical inoperability. Further validation in larger cohorts and investigation of effective adjuvant systemic therapies may be warranted.

Final efficacy outcomes of atezolizumab with chemoradiation for unresectable NSCLC: The phase II DETERRED trial

INTRODUCTION

The phase II DETERRED trial assessed the safety and efficacy of consolidation and concurrent immunotherapy with chemoradiation in unresectable locally advanced non-small cell lung cancer. We present updated efficacy analysis of this trial.

METHODS

The trial was conducted in 2 parts with patients in part 1 (n = 10) receiving chemoradiation with consolidation atezolizumab, while patients in part 2 (n = 30) received concurrent and consolidation atezolizumab. Progression-free survival (PFS), time to second progression (PFS2), and overall survival (OS) were assessed using Kaplan-Meier analysis. Subset analyses were performed by programmed cell death ligand-1 (PD-L1) status and targetable driver oncogene mutation status.

RESULTS

At a median follow-up of 39.2 months, the median PFS for part 1 was 18.9 months and 15.1 months for part 2. Median OS for part 1 was 26.5 months and was not reached for part 2. For the cohort, 3-year OS was 53.8%, while 4-year OS was 47.4%. Patients with targetable driver oncogene mutations had a median PFS of 9.4 months and OS of not reached compared to 16.6 months (HR: 3.49, p = 0.02) and 26.9 months (HR: 0.40, p = 0.12) respectively compared to those without targetable driver oncogene mutations. Patients with PD-L1 < 1% had median PFS of 11.0 months and OS of 26.5 months compared to 27.4 months (HR: 2.01, p = 0.10) and not reached (HR: 1.49, p = 0.41) respectively for those with PD-L1 ≥ 1%.

CONCLUSIONS

In the DETERRED trial, chemoradiation with concurrent and/or consolidative atezolizumab led to comparable efficacy as consolidative durvalumab in the PACIFIC trial. The presence of targetable driver oncogene mutations led to worse PFS, while PD-L1 < 1% trended to worse PFS.

Definitive Local Consolidative Therapy for Oligometastatic Solid Tumors: Results From the Lead-in Phase of the Randomized Basket Trial EXTEND

PURPOSE

The benefit of local consolidative therapy (LCT) for oligometastasis across histologies remains uncertain. EXTernal beam radiation to Eliminate Nominal metastatic Disease (EXTEND; NCT03599765) is a randomized phase 2 basket trial evaluating the effectiveness of LCT for oligometastatic solid tumors. We report here the prospective results of the single-arm "lead-in" phase intended to identify histologies most likely to accrue to histology-specific endpoints in the randomized phase.

METHODS AND MATERIALS

Eligible histologies included colorectal, sarcoma, lung, head and neck, ovarian, renal, melanoma, pancreatic, prostate, cervix/uterine, breast, and hepatobiliary. Patients received LCT to all sites of active metastatic disease and primary/regional disease (as applicable) plus standard-of-care systemic therapy or observation. The primary endpoint in EXTEND was progression-free survival (PFS), and the primary endpoint of the lead-phase was histology-specific accrual feasibility. Adverse events were graded by Common Terminology Criteria for Adverse Events version 4.0.

RESULTS

From August 2018 through January 2019, 50 patients were enrolled and 49 received definitive LCT. Prostate, breast, and kidney were the highest enrolling histologies and identified for independent accrual in the randomization phase. Most patients (73%) had 1 or 2 metastases, most often in lung or bone (79%), and received ablative radiation (62%). Median follow-up for censored patients was 38 months (range, 16-42 months). Median PFS was 13 months (95% confidence interval, 9-24), 3-year overall survival rate was 73% (95% confidence interval, 57%-83%), and local control rate was 98% (93 of 95 tumors). Two patients (4%) had Common Terminology Criteria for Adverse Events grade 3 toxic effects related to LCT; no patient had grade 4 or 5 toxic effects.

CONCLUSIONS

The prospective lead-in phase of the EXTEND basket trial demonstrated feasible accrual, encouraging PFS, and low rates of severe toxic effects at mature follow-up. The randomized phase is ongoing with histology-based baskets that will provide histology-specific evidence for LCT in oligometastatic disease.

Outcomes With Local Therapy and Tyrosine Kinase Inhibition in Patients With ALK/ROS1/RET-Rearranged Lung Cancers

PURPOSE

Local therapy prolongs progression-free survival in patients with oligometastatic non-small-cell lung cancers treated with chemotherapy. We previously reported that local therapy also prolongs survival and time to next therapy in patients on tyrosine kinase inhibitors (TKIs) for EGFR-mutant lung adenocarcinomas. Here, we investigate the role of local therapy in patients progressing on TKIs for ALK/ROS1/RET-rearranged lung adenocarcinomas.

MATERIALS AND METHODS

Patients with advanced ALK/ROS/RET-rearranged lung adenocarcinomas who underwent radiation, surgery, or percutaneous thermal ablation from 2012 to 2020 for progression on an ALK/ROS1/RET TKI were included. Progression patterns were identified. Times from local therapy to progression, next therapy, and death were measured.

RESULTS

Sixty-one patients with ALK (n = 37), ROS1 (n = 12), and RET (n = 12) fusions were identified. Patients received radiotherapy (92%), surgery (13%), and percutaneous thermal ablation (8%). Local therapy was administered for solitary/oligoprogressive (94%) or polyprogressive (6%) disease. For most patients (85%), local therapy addressed all progressing sites. The median times from any local therapy to subsequent progression and next systemic therapy were 6.8 months (95% CI, 5.1 to 8.1) and 10 months (95% CI, 8.4 to 15.3), respectively. Third or greater local therapy was associated with shorter time to progression and next therapy than first/second local therapies (hazard ratio, 4.97; P < .001 and hazard ratio, 2.48; P < .001). The median overall survival from first local therapy was 34 months (95% CI, 26 to not reached).

CONCLUSION

Local therapy for progression on ALK, ROS1, or RET TKIs is associated with clinically meaningful time on continued TKI therapy beyond progression, especially earlier in the course of disease.

Radiation Oncology AcaDemic Mentorship Program (ROADMAP) for Junior Faculty: One-Year Results of a Prospective Single Institution Initiative

PURPOSE

Although mentorship has been associated with promotion, job satisfaction, and retention, data are limited on the mentorship experience of clinical- versus research-track physicians as well as feasibility and relative priority of formal program components.

METHODS AND MATERIALS

Within a single-institution, multi-site, academic network, we implemented a Radiation Oncology AcaDemic Mentorship Program (ROADMAP) for junior faculty. Validated surveys assessing mentee satisfaction were distributed at baseline and 1 year. The statistical analysis included Wilcoxon rank sum and signed tests. Mentees assessed the likelihood to recommend each program component (10-point Likert-type scale), and means with standard error (SE) are reported.

RESULTS

Among 42 eligible junior faculty, 36 (86%) opted into the program. The median time since residency was 2.5 years (interquartile range, 1.75-5.25) on the clinical track (n = 12) and 3 years (interquartile range, 2.75-5.00) on the research track (n = 24). At baseline, research-track physicians reported higher satisfaction with mentoring than physicians on the clinical track (2.92 vs 2.16; P = .02). Among 32 physicians completing 1 year, overall satisfaction with mentoring increased compared with baseline (2.72 vs 3.87; P < .001), which persisted on subset analysis for both clinical- (2.16 vs 4.03; P < .001) and research-track physicians (2.99 vs 3.77; P = .005). At 1 year, 28 mentees (88%) opted to continue the program. Program components were rated 8.25 (SE, 0.37) for mentor-mentee pairings, 7.22 (SE, 0.39) for goal setting, 6.84 (SE, 0.47) for administrative support, 6.69 (SE, 0.44) for peer mentoring, and 6.53 (SE, 0.45) for steering committee oversight. Ratings of peer mentoring were not associated with track (P = .59) or years in practice (P = .29).

CONCLUSIONS

Clinical-track physicians may be less satisfied with mentorship than research-track faculty. However, all junior faculty, regardless of track, appeared to benefit from formalizing dyadic mentor-mentee relationships, goal setting, and peer mentoring. Further work is needed to determine the role of mentorship in addressing physician burnout.

Systemic and Oligo-Acquired Resistance to PD-(L)1 Blockade in Lung Cancer

PURPOSE

Clinical patterns and the associated optimal management of acquired resistance to PD-(L)1 blockade are poorly understood.

EXPERIMENTAL DESIGN

All cases of metastatic lung cancer treated with PD-(L)1 blockade at Memorial Sloan Kettering were reviewed. In acquired resistance (complete/partial response per RECIST, followed by progression), clinical patterns were distinguished as oligo (OligoAR ≤ 3 lesions of disease progression) or systemic (sAR). We analyzed the relationships between patient characteristics, burden/location of disease, outcomes, and efficacy of therapeutic interventions.

RESULTS

Of 1,536 patients, 312 (20%) had an initial response and 143 developed AR (9% overall, 46% of responders). OligoAR was the most common pattern (80/143, 56%). Baseline tumor mutational burden, depth of response, and duration of response were significantly increased in oligoAR compared with sAR (P < 0.001, P = 0.03, P = 0.04, respectively), whereas baseline PD-L1 and tumor burden were similar. Post-progression, oligoAR was associated with improved overall survival (median 28 months vs. 10 months, P < 0.001) compared with sAR. Within oligoAR, post-progression survival was greater among patients treated with locally-directed therapy (e.g., radiation, surgery; HR, 0.41; P = 0.039). Fifty-eight percent of patients with oligoAR treated with locally-directed therapy alone are progression-free at last follow-up (median 16 months), including 13 patients who are progression-free more than 2 years after local therapy.

CONCLUSIONS

OligoAR is a common and distinct pattern of acquired resistance to PD-(L)1 blockade compared with sAR. OligoAR is associated with improved post-progression survival and some cases can be effectively managed with local therapies with durable benefit.

Tumor volume as a predictor of cell free DNA mutation detection in advanced non-small cell lung cancer

Background

Cell free DNA (cfDNA) is an exciting biomarker with applications across the cancer care continuum. Determinants of cfDNA shedding dynamics remain an active research area. We performed a detailed analysis of tumor volume and factors associated with detection of cfDNA mutations.

Methods

Patients with advanced non-small cell lung cancers (NSCLCs) were prospectively enrolled on a plasma biomarker protocol. Next generation sequencing (NGS) was performed using a validated, bias-corrected, hybrid-capture panel assay of lung cancer-associated genes. Volume of tumor in different subsites and total tumor volume were determined through manual volume delineation using PET/CT and brain magnetic resonance imaging (MRI) imaging. The primary endpoint was detection of cfDNA mutation; secondary endpoints were overall survival (OS) and variant allele frequency (VAF).

Results

There were 110 patients included, 78 of whom had at least one mutation detected. Median total tumor volume for the entire cohort, patients with mutation detected, and patients with no mutation detected were 66 mL (range, 2-1,383 mL), 76 mL (range, 5-1,383 mL), and 45 mL (range, 2-460 mL), respectively (P=0.002; mutation detected vs. not). The optimal total tumor volume threshold to predict increased probability of mutation detection was 65 mL (P=0.006). Total tumor volume greater than 65 mL was a significant predictor of mutation detection on multivariate analysis (OR: 4.30, P=0.003). Significant predictors of OS were age (HR: 1.04, P=0.002), detection of cfDNA mutation (HR: 2.11, P=0.024), and presence of bone metastases (HR: 1.66, P=0.047).

Conclusions

Total tumor volume greater than 65 mL was associated with cfDNA mutation detection in patients with advanced NSCLC.

Prospective clinical evaluation of integrating a radiation anatomist for contouring in routine radiation treatment planning

Purpose

A radiation anatomist was trained and integrated into clinical practice at a multi-site academic center. The primary objective of this quality improvement study was to determine whether a radiation anatomist improves the quality of organ-at-risk (OAR) contours, and secondarily to determine the impact on efficiency in the treatment planning process.

Methods and Materials

From March to August 2020, all patients undergoing computed tomography–based radiation planning at 2 clinics at Memorial Sloan Kettering Cancer Center were assigned using an “every other” process to either (1) OAR contouring by a radiation anatomist (intervention) or (2) contouring by the treating physician (standard of care). Blinded dosimetrists reported OAR contour quality using a 3-point scoring system based on a common clinical trial protocol deviation scale (1, acceptable; 2, minor deviation; and 3, major deviation). Physicians reported time spent contouring for all cases. Analyses included the Fisher exact test and multivariable ordinal logistic regression.

Results

There were 249 cases with data available for the primary endpoint (66% response rate). The mean OAR quality rating was 1.1 ± 0.4 for the intervention group and 1.4 ± 0.7 for the standard of care group (P < .001), with subset analysis showing a significant difference for gastrointestinal cases (n = 49; P <.001). Time from simulation to contour approval was reduced from 3 days (interquartile range [IQR], 1-6 days) in the control group to 2 days (IQR, 1-5 days) in the intervention group (P = .007). Both physicians and dosimetrists self-reported decreased time spent contouring in the intervention group compared with the control group, with a decreases of 8 minutes (17%; P < .001) and 5 minutes (50%; P = .002), respectively. Qualitative comments most often indicated edits required to bowel contours (n = 14).

Conclusions

These findings support improvements in both OAR contour quality and workflow efficiency with implementation of a radiation anatomist in routine practice. Findings could also inform development of autosegmentation by identifying disease sites and specific OARs contributing to low clinical efficiency. Future research is needed to determine the potential effect of reduced physician time spent contouring OARs on burnout.

Implementation Strategies to Increase Clinical Trial Enrollment in a Community-Academic Partnership and Impact on Hispanic Representation: An Interrupted Time Series Analysis

PURPOSE

Community-academic partnerships have the potential to improve access to clinical trials for under-represented minority patients who more often receive cancer treatment in community settings. In 2017, the Memorial Sloan Kettering (MSK) Cancer Center began opening investigator-initiated clinical trials in radiation oncology in targeted community-based partner sites with a high potential to improve diverse population accrual. This study evaluates the effectiveness of a set of implementation strategies for increasing overall community-based enrollment and the resulting proportional enrollment of Hispanic patients on trials on the basis of availability in community-based partner sites.

METHODS

An interrupted time series analysis evaluating implementation strategies was conducted from April 2018 to September 2021. Descriptive analysis ofHispanic enrollment on investigator-initiated randomized therapeutic radiation trials open at community-based sites was compared with those open only at themain academic center.

RESULTS

Overall, 84 patients were enrolled in clinical trials in the MSK Alliance, of which 48 (56%) identified as Hispanic. The quarterly patient enrollment pre- vs postimplementation increased from 1.39 (95% CI, -3.67 to 6.46) to 9.42 (95% CI, 2.05 to 16.78; P5 .017). In the investigator-initiated randomized therapeutic radiation trials open in the MSK Alliance, Hispanic representation was 11.5% and 35.9% in twometastatic trials and 14.2% in a proton versus photon trial. Inmatched trials open only at the main academic center, Hispanic representation was 5.6%, 6.0%, and 4.0%, respectively.

CONCLUSION

A combination of practice-level and physician-level strategies implemented at community-based partner sites was associated with increased clinical trial enrollment, which translated to improved Hispanic representation. This supports the role Q:2 of strategic community-academic partnerships in addressing disparities in clinical trial enrollment.

The Role of Ablative Radiotherapy in Older Adults With Limited Metastatic Disease

For patients with oligometastatic cancer, radiotherapy presents a promising avenue for achieving meaningful symptom relief and durable disease control. Data from recently published and ongoing randomized studies are helping to define the appropriate contexts for effective intervention with stereotactic ablative body radiotherapy (SABR) in the oligometastatic setting. Importantly, older adults represent a significant portion of patients with oligometastatic disease, yet often comprise a minority of patients in clinical trials. Moreover, older adults of the same chronologic age may have variable degrees of fitness and frailty. In this review, we highlight the specific challenges and considerations for the use of radiotherapy for older adults with oligometastatic disease-noting the importance of geriatric assessments in clinical decision-making about the appropriateness of SABR and other metastasis-directed therapies in this population. We then review data from existing trials, including a subset analysis of adverse events and survival estimates among older adults enrolled in the landmark SABR-COMET trial. Finally, we discuss future directions for research, including the need for focused clinical trials in older adult cohorts. Ultimately, a multidisciplinary approach is critical when carefully balancing the potential risks and benefits of this emerging treatment paradigm in the older adult population.

Brief Report: Surgical Complexity of Pulmonary Resections Performed for Oligometastatic Non-Small Cell Lung Cancer

Introduction

Methods

Results

Conclusions

Pre-treatment immune status predicts disease control in NSCLCs treated with chemoradiation and durvalumab

BACKGROUND

The impact of peripheral blood immune measures and radiation-induced lymphopenia on outcomes in non-small cell lung cancer (NSCLC) patients treated with concurrent chemoradiation (cCRT) and immune check point inhibition (ICI) has yet to be fully defined.

METHODS

Stage III NSCLC patients treated with cCRT and ≥1 dose of durvalumab across a cancer center were examined. Peripheral blood counts were assessed pre-cCRT, during cCRT and at the start of ICI. These measures and risk-scores from two published models estimating radiation dose to immune-bearing organs were tested for association with disease control.

RESULTS

We assessed 113 patients treated with cCRT and a median of 8.5 months of durvalumab. Median PFS was 29 months (95% CI 18-35 months). A lower pre-cCRT ALC (HR: 0.51 (95% CI: 0.32-0.82), p = 0.02) and a higher pre-cCRT ANC (HR: 1.14 (1.06-1.23), p = 0.005) were associated with poor PFS. Neither ALC nadir, ALC at ICI start, ANC at ICI start or the normalized change in ALC from pre-cCRT to nadir were significantly associated with PFS (p = 0.07-0.49). Also, risk scores from the two radiation-dose models were not associated with PFS (p = 0.14, p = 0.21) but were so with the ALC Nadir (p = 0.001, p = 0.002). A higher pre-cCRT NLR was the strongest predictor for PFS (HR: 1.09 (1.05-1.14), p = 0.0001). The 12-month PFS in patients with the bottom vs. top NLR tertile was 84% vs 46% (p = 0.000004).

CONCLUSIONS

Baseline differences in peripheral immune cell populations are associated with disease outcomes in NSCLC patients treated with cCRT and ICI.

Clinical outcomes of dose-escalated hypofractionated external beam radiotherapy (5 Gy x 5 fractions) for spine metastasis

Purpose

Methods and Materials

Results

Conclusions