Immunotherapy and Radiation Therapy Sequencing in Breast Cancer: A Systematic Review

PURPOSE

In the past decade, immune checkpoint inhibitors (ICIs) have emerged as a treatment option for metastatic breast cancer (BC). More recently, ICIs have been approved in the perioperative setting. This has led to clinical scenarios where radiation therapy (RT) is given concurrently with ICIs. On the other hand, moderate and ultrahypofractionated schedules of RT are being widely adopted in the adjuvant setting, in addition to an increased use of metastasis-directed therapy. Furthermore, RT can modulate the tumor microenvironment and induce a systemic response at nonirradiated sites, an "abscopal effect." The amplification of antitumor immune response is used as the rationale behind the concomitant use of ICIs and RT. To date, there is a lack of literature on the optimal sequence, timing, dose/fractionation schema, and treated RT volumes with ICIs in patients with BC, especially in the era of ultrahypofractionation.

METHODS AND MATERIALS

We conducted a systematic review to delineate the reported treatment details, safety, and efficacy of combining ICI and RT in patients with BC. PubMed, Embase, and Cochrane CENTRAL were searched between 2014 and 2023. Data were extracted to assess the details of ICIs/RT delivery, safety, and efficacy.

RESULTS

Of the 12 eligible studies, 9 involved patients with metastatic BC. Most studies were phase 1/2, had a small sample size (range, 8-28), and were heterogenous in patient population and reported outcomes. The combination was reported to be safe. We identified 1 study in the perioperative setting, which did a posthoc analysis of safety/efficacy of ICIs in the adjuvant setting with receipt and pattern of RT.

CONCLUSIONS

In conclusion, there are limited data on the dose, timing, fractionation, and volumes of RT in both the adjuvant and metastatic setting in BC. Ongoing/future trials should collect and report such data on RT details, whenever RT is used in combination with ICIs.

Appraisal of Systemic Treatment Strategies in Early HER2-Positive Breast Cancer-A Literature Review

BACKGROUND

The overexpression of the human epidermal growth factor receptor 2 (HER2+) accounts for 15-20% of all breast cancer phenotypes. Even after the completion of the standard combination of chemotherapy and trastuzumab, relapse events occur in approximately 15% of cases. The neoadjuvant approach has multiple benefits that include the potential to downgrade staging and convert previously unresectable tumors to operable tumors. In addition, achieving a pathologic complete response (pCR) following preoperative systemic treatment is prognostic of enhanced survival outcomes. Thus, optimal evaluation among the suitable strategies is crucial in deciding which patients should be selected for the neoadjuvant approach.

METHODS

A literature search was conducted in the Embase, Medline, and Cochrane electronic libraries.

CONCLUSION

The evaluation of tumor and LN staging and, hence, stratifying BC recurrence risk are decisive factors in guiding clinicians to optimize treatment decisions between the neoadjuvant versus adjuvant approaches. For each individual case, it is important to consider the most likely postsurgical outcome, since, if the patient does not obtain pCR following neoadjuvant treatment, they are eligible for adjuvant T-DM1 in the case of residual disease. This review of HER2-positive female BC outlines suitable neoadjuvant and adjuvant systemic treatment strategies for guiding clinical decision making around the selection of an appropriate therapy.

Impact of 18F-Labeled Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography Versus Conventional Staging in Patients With Locally Advanced Breast Cancer

PURPOSE

Patients with locally advanced breast cancer (LABC) typically undergo staging tests at presentation. If staging does not detect metastases, treatment consists of curative intent combined modality therapy (neoadjuvant chemotherapy, surgery, and regional radiation). Positron emission tomography-computed tomography (PET-CT) may detect more asymptomatic distant metastases, but the evidence is based on uncontrolled studies.

METHODS

For inclusion, patients had histological evidence of invasive ductal carcinoma of the breast and TNM stage III or IIb (T3N0, but not T2N1). Consenting patients from six regional cancer centers in Ontario were randomly assigned to 18F-labeled fluorodeoxyglucose PET-CT or conventional staging (bone scan, CT of the chest/abdomen and pelvis). The primary end point was upstaging to stage IV. A key secondary outcome was receiving curative intent combined modality therapy (ClinicalTrials.gov identifier: NCT02751710).

RESULTS

Between December 2016 and April 2022, 184 patients were randomly assigned to whole-body PET-CT and 185 patients to conventional staging. Forty-three (23%) PET-CT patients were upstaged to stage IV compared with 21 (11%) conventional staged patients (absolute difference, 12.3% [95% CI, 3.9 to 19.9]; P = .002). Consequently, treatment was changed in 35 (81.3%) of 43 upstaged PET-CT patients and 20 (95.2%) of the 21 upstaged conventional patients. Subsequently, 149 (81%) patients in the PET-CT group received combined modality treatment versus 165 (89.2%) patients in the conventional staging group (absolute difference, 8.2% [95% CI, 0.1 to 15.4]; P = .03).

CONCLUSION

In patients with LABC, PET-CT detected more distant metastases than conventional staging, and fewer PET-CT patients received combined modality therapy. Our randomized trial demonstrates the utility of the PET-CT staging strategy.

Early mortality in patients with cancer treated with immune checkpoint inhibitors in routine practice

BACKGROUND

We sought to estimate the proportion of patients with cancer treated with immune checkpoint inhibitors (ICI) who die soon after starting ICI in the real world and examine factors associated with early mortality (EM).

METHODS

We conducted a retrospective cohort study using linked health administrative data from Ontario, Canada. EM was defined as death from any cause within 60 days of ICI initiation. Patients with melanoma, lung, bladder, head and neck, or kidney cancer treated with ICI between 2012 and 2020 were included.

RESULTS

A total of 7126 patients treated with ICI were evaluated. Fifteen percent (1075 of 7126) died within 60 days of initiating ICI. The highest mortality was observed in patients with bladder and head and neck tumors (approximately 21% each). In multivariable analysis, previous hospital admission or emergency department visit, prior chemotherapy or radiation therapy, stage 4 disease at diagnosis, lower hemoglobin, higher white blood cell count, and higher symptom burden were associated with higher risk of EM. Conversely, patients with lung and kidney cancer (compared with melanoma), lower neutrophil to lymphocytes ratio, and with higher body mass index were less likely to die within 60 days post ICI initiation. In a sensitivity analysis, 30-day and 90-day mortality were 7% (519 of 7126) and 22% (1582 of 7126), respectively, with comparable clinical factors associated with EM identified.

CONCLUSIONS

EM is common among patients treated with ICI in the real-world setting and is associated with several patient and tumor characteristics. Development of a validated tool to predict EM may facilitate better patient selection for treatment with ICI in routine practice.

A Multi-Centre Randomized Study Comparing Two Standard of Care Chemotherapy Regimens for Lower-Risk HER2-Positive Breast Cancer

BACKGROUND

Neither paclitaxel plus trastuzumab (P-H) nor docetaxel-cyclophosphamide plus trastuzumab (TC-H) have been prospectively compared in HER2-positive early-stage breast cancer (EBC). A randomized trial was performed to assess the feasibility of a larger study.

METHODS

Lower-risk HER2-positive EBC patients were randomized to either P-H or TC-H treatment arms. The co-primary feasibility outcomes were: ≥75% patient acceptability rate, active trial participation of ≥50% of medical oncologists, ≥75% and ≥90% treatment completion, and receipt rate of planned cycles of chemotherapy, respectively.

SECONDARY OUTCOMES

Febrile neutropenia (FN) rate, treatment-related hospitalizations, health-related quality of life (HR-QoL) questionnaires. Analyses were performed by per protocol and intention-to-treat.

RESULTS

Between May 2019 and March 2021, 49 of 52 patients agreed to study participation (94% acceptability rate). Fifteen (65%) of 23 medical oncologists approached patients. Rates of FN were higher (8.3% vs. 0%) in the TC-H vs. P-H arm. Median (IQR) changes in scores from baseline in FACT-Taxane Trial Outcome Index at 24 weeks were -4 (-10, -1) vs. -6.5 (-15, -2) for TC-H and P-H arms, respectively.

CONCLUSIONS

A randomized trial comparing P-H and TC-H was feasible. Expansion to a larger trial would be feasible to explore patient-reported outcomes of these adjuvant HER2 chemotherapy regimens.

Abstract P3-07-14: A phase II study of CFI-400945 in patients with advanced/metastatic cancer: Canadian Cancer Trials Group (CCTG) IND.237

Background:

CFI-400945 is a selective oral inhibitor of Polo-like Kinase 4 (PLK4), a controller of centriole duplication and mitotic progression identified by functional screening of genomically unstable breast cancer (BC). IND.237 (NCT01954316) is an open label, multicentre, phase 2 study in HER2 negative metastatic breast cancer (MBC) with 3 cohorts, 1 enriched for PTEN loss of function. Enrollment started in 2018 at 64mg based on a previously established recommended phase 2 dose (RP2D). The initial patients had higher than expected grade 3/4 neutropenia which led to a voluntary hold and dose de-escalation; the new RP2D was declared at 32mg as previously reported Here we report the results of the phase 2 study of CFI-400945 in advanced BC patients.

Materials and Methods:

49 patients were enrolled across 3 cohorts: 1: triple negative; 2: ER+/HER2- PTEN low (by IHC); 3: ER+/HER2-, PTEN intact. The primary outcome is objective response rate (ORR); secondary outcomes included disease control rate (DCR) >16w, and safety. A Simon 2-stage design was used (9 – 25 pts planned for each cohort). CFI-400945 would be considered active if ≥3 responses were observed in any given cohort. Eligibility included ECOG 0-1, adequate organ function and receipt of at ≥1 prior line of cytotoxic chemotherapy in any setting including anthracycline taxane (unless contraindicated). Treatment was 32mg 7d on 7d off in cycle 1 (cycle length=28d), then continuously starting cycle 2. Safety assessments were performed each cycle and response (RECIST 1.1) every 2 cycles.

Results:

60 patients have been screened, 49 enrolled: 10 were in initial dose ranging and were excluded from phase 2 response assessment. 10 patients were enrolled in cohort 1, 4 in cohort 2, and 25 in cohort 3. Table 1 presents patient characteristics and response results. 1 patient in cohort 3 has not had disease re-assessed at time of abstract submission. The most common adverse events have been cytopenias, nausea, fatigue, headache, constipation and vomiting. Less than 5% of patients experienced a non-hematologic AE > grade 3; 33% experienced ≥ grade 3 neutropenia.

Conclusions:

CFI-400945 32mg is well tolerated in this MBC population with moderate incidence of uncomplicated neutropenia. The TNBC cohort so this arm has been closed to further accrual for lack of responses. The PTEN loss group has been slow to accrue and remains open. Responses in the ER+/HER2- arm are encouraging – results from patients remaining on study are awaited and correlative studies to identify features associated with responses are underway.

Acknowledgements: Sponsored by the Canadian Cancer Trials Group. Supported by Stand Up To Cancer Canada (scientific partner AACR) Canadian Cancer Society (CCS) Breast Cancer Dream Team Research Funding, Ontario Institute for Cancer Research (funding provided by the Government of Ontario) and grants from CCS to CCTG.

Table 1. Table 1. Patient characteristics and response rates in each cohort treated with CFI-400945.

Citation Format: David W. Cescon, John Hilton, Philippe Bedard, Phillip Blanchette, Rossanna C. Pezo, Ayesha Bashir, Vikaash Kumar, Terry L. Ng, Arif Awan, Anthony Lott, Jacques Antoun Raphael, Linda Hagerman, Mark Bray, Lindsay Muyot, Jesus Fuentes Antras, Lesley Seymour, Dongsheng Tu, Pierre-Olivier Gaudreau, Moira Rushton. A phase II study of CFI-400945 in patients with advanced/metastatic cancer: Canadian Cancer Trials Group (CCTG) IND.237 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-07-14.

Clinical Utility of Multigene Profiling Assays in Early-Stage Invasive Breast Cancer: An Ontario Health (Cancer Care Ontario) Clinical Practice Guideline

OBJECTIVE

The purpose of this guideline is to determine the clinical utility of multigene profiling assays in individuals with early-stage invasive breast cancer.

METHODS

This guideline was developed by Ontario Health (Cancer Care Ontario)'s Program in Evidence-Based Care (PEBC) through a systematic review of relevant literature, patient- and caregiver-specific consultation and internal and external reviews. Recommendation 1: In patients with early-stage estrogen receptor (ER)-positive/human epidermal growth factor 2 (HER2)-negative breast cancer, clinicians should consider using multigene profiling assays (i.e., Oncotype DX, MammaPrint, Prosigna, EndoPredict, and the Breast Cancer Index) to help guide the use of systemic therapy. Recommendation 2: In patients with early-stage node-negative ER-positive/HER2-negative disease, clinicians may use a low-risk result from Oncotype DX, MammaPrint, Prosigna, EndoPredict/EPclin, or Breast Cancer Index assays to support a decision not to use adjuvant chemotherapy. Recommendation 3: In patients with node-negative ER-positive/HER2-negative disease, clinicians may use a high-risk result from Oncotype DX to support a decision to offer chemotherapy. A high Oncotype DX recurrence score is capable of predicting adjuvant chemotherapy benefit. Recommendation 4: In postmenopausal patients with ER-positive/HER2-negative tumours and one to three nodes involved (N1a disease), clinicians may withhold chemotherapy based on a low-risk Oncotype DX or MammaPrint score if the decision is supported by other clinical, pathological, or patient-related factors. Recommendation 5: The evidence to support the use of molecular profiling to select the duration of endocrine therapy is evolving. In patients with ER-positive disease, clinicians may consider using a Breast Cancer Index (H/I) high assay result to support a decision to extend adjuvant endocrine therapy if the decision is supported by other clinical, pathological, or patient-related factors.

Two-year results of a randomised trial comparing 4- versus 12-weekly bone-targeted agent use in patients with bone metastases from breast or castration-resistant prostate cancer

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Optimal dosing interval of bone-targeting agents (BTAs) has not been fully defined.

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Study of 4 vs 12-weekly BTAs in breast or prostate cancer pts with bone metastases.

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Study arms showed no significant differences SSE rates, time to SSEs or toxicity.

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There were however significant differences in cost-effectiveness results.

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On study SSE (12-weekly arm) associated with slight increase in subsequent SSEs.

Background

We present the 2-year results of a randomised trial comparing 4- versus 12-weekly bone-targeting agents (BTAs) in patients with bone metastases from breast or castration-resistant prostate cancer (CRPC).

Patients and Methods

Patients with bone metastases from breast or CRPC, who were going to start or were already receiving BTAs, were randomised to 4- or 12-weekly BTA treatment for 2 years. The endpoints were: symptomatic skeletal events (SSE) rates, time to SSEs, toxicity and cost-effectiveness.

Results

Of 263 patients (160 breast cancer, 103 CRPC), 133 (50.6%) and 130 (49.4%) were randomised to the 4- and 12-weekly groups, respectively. BTAs included denosumab (56.3%), zoledronate (24.0%) and pamidronate (19.8%). After 2 years, the cumulative incidence rate (95% CI) of SSEs was 32.7% (24.6% to 41.1%) and 28.1% (20.3% to 36.4%) for the 4- and 12-weekly intervention groups respectively. The hazard ratio for time to first SSE was 0.96 (95% CI = 0.63 to 1.47). However, in a post hoc analysis, those patients who had an on-study SSE, there was a small non-statistical increased risk of subsequent SSEs among patients on the 12-weekly dosing arm (HR = 1.14; 95% CI – 0.90–1.44). BTA-related toxicity rates were similar between study arms. A cost-utility analysis showed that 12-weekly BTA is cost-effective from a public payer’s perspective.

Conclusion

These results in addition to those previously reported for de-escalating zoledronate, would support that de-escalation of commonly used BTAs is a reasonable and economically valid treatment option. While not statistically significant, the increase in subsequent SSEs in the 12-weekly arm requires further exploration.

A randomised trial of 4- versus 12-weekly administration of bone-targeted agents in patients with bone metastases from breast or castration-resistant prostate cancer

BACKGROUND

Optimal dosing of bone-targeted agents (BTAs), in patients with bone metastases remains an important clinical question. This trial compared 4-weekly versus 12-weekly therapy.

PATIENTS AND METHODS

Patients with bone metastases from breast or castration-resistant prostate cancer (CRPC), who were going to start or already on BTAs, were randomised 1:1 to 4-weekly or 12-weekly BTA treatment for one year. Primary end point was change in health-related quality of life (HRQoL)-physical function European Organisation for Research and Treatment of Cancer (EORTC)-QLQ-C30). Secondary end points included pain (EORTC-QLQ-BM22), global health status (EORTC-QLQ-C30), symptomatic skeletal events (SSEs) rates and time to SSEs. Primary analysis was per protocol and a non-inferiority margin of 5 points was used.

RESULTS

Of 263 patients (160 breast cancer, 103 CRPC), 133 (50.6%) and 130 (49.4%) were randomised to the 4- and 12-weekly groups, respectively. BTAs included denosumab (56.3%), zoledronate (24.0%) and pamidronate (19.8%). Using repeated-measures analysis, across all time points, patients in the 4-weekly arm had a mean HRQL-physical subdomain score which was 1.2 (95% confidence interval: -1.6 to 4.0) higher than the 12-weekly arm. The study met the definition of non-inferiority for our primary outcome. Secondary outcomes showed no significant difference in scores for pain, global health status, SSE rates and SSE-free survival between arms. Subgroup analyses for cancer type, prior BTA use or BTA type showed no significant difference between arms.

CONCLUSION

These results in addition to those previously reported for de-escalating zoledronate and systematic reviews in both breast and prostate cancers, would support that de-escalation of commonly used BTAs is a reasonable treatment option.

Do all patients with HER2 positive breast cancer require one year of adjuvant trastuzumab? A systematic review and meta-analysis

One year of adjuvant trastuzumab is considered the standard treatment for patients with HER2 positive breast cancer. However, a shorter duration of trastuzumab may be associated with reduced costs and side effects. Results from randomized trials with diverse non-inferiority margins comparing one year to a shorter duration of adjuvant trastuzumab are not consistent and have not been systematically reviewed using a non-inferiority meta-analysis approach. We conducted a systematic review and meta-analysis of randomized trials to assess whether a shorter duration of adjuvant trastuzumab was non-inferior to one year of treatment or not. The non-inferiority margin for the meta-analysis was pre-defined as the median of the margins of all the trials included. Data of 11,376 patients from 5 trials were analyzed. Non-inferiority margins in included studies varied from 1.15 to 1.53 with median of 1.29 for HR of DFS. A shorter duration of trastuzumab was non-inferior to one year of therapy for DFS (HR 1.13, 95%CI 1.03-1.24) but inconclusive for OS (HR 1.14, 95%CI 1.00-1.30). In a subgroup analysis for DFS outcome, shorter therapy was non-inferior in patients with ER positive disease (HR 1.10, 95%CI 0.95-1.28) and those with sequential therapy (HR 0.97, 95%CI 0.75-1.27) and when the duration of treatment was 6 months (HR 1.09, 95%CI 0.98-1.22). Although a shorter duration of adjuvant trastuzumab was non-inferior to one year of therapy for DFS in patients with HER2 positive breast cancer based on our HR margin of 1.29, any benefit of a shorter duration comes at a loss of efficacy with an increase in absolute risk up to 3.9% for 5 year DFS. Whether the potential increased risk is clinically acceptable for the benefits of a shorter duration remains debatable.

Abstract 770: Exploitation of treatment induced tumor lysis to enhance sensitivity of ctDNA analysis: a first-in-human pilot study

Background: Blood based liquid biopsies examining circulating tumour DNA (ctDNA) have increasing applications in non-small cell lung cancer (NSCLC). Limitations in sensitivity, especially in patients with limited disease burden, remains a barrier to ctDNA replacing tissue-based testing. There is a paucity of data regarding the optimal time to measure ctDNA, specifically the dynamics of ctDNA levels in the hours to days following a new and effective treatment. We hypothesize that chemotherapy or radiation will yield an increased abundance of ctDNA in plasma by inducing tumor lysis, allowing for the detection of genetic alterations that were occult in baseline testing.

Methods: Two prospective cohorts of twenty patients (pts) with stage III/IV NSCLC were enrolled. Cohort 1 (C1) contained patients starting the first cycle of platinum doublet chemoradiation (C1a, n=10) or the first cycle of platinum doublet cytotoxic chemotherapy ± immunotherapy without concurrent radiation (C1b, n=10). Cohort 2 (C2) contained patients receiving palliative radiation. Consenting patients provided baseline samples, the first ≤ 14 days prior to starting treatment and one immediately prior to treatment. In C1, subsequent samples were collected (A) 2-3, (B) 4-6, (C) 18-72 and (D) 42-96 hours post initiation of chemotherapy. Pts in C2 had samples collected immediately prior to radiotherapy fractions 2, 3, and 4. Samples were analyzed for ctDNA using the 36-gene amplicon-based NGS Inivata InVisionFirst®-Lung assay.

Results: Complete results were available for the first 28 of 40 enrolled pts, C1a - 8 pts, C1b - 8 pts, C2 - 12 pts. Detectable ctDNA was present at baseline in 21 pts (75%), 4 additional pts (14.3%) had detectable ctDNA in post treatment samples (C1a - 2pts, C1b - 1pt, C2 - 1pt). Three of the patients with detectable ctDNA at baseline (10.7%) had new genetic alterations detected in post treatment samples. A total of 7/28 pts (25%) had new genetic alterations detected in the post treatment samples. Mutant molecule numbers increased with treatment in 19 of 25 (76%) pts with detectable ctDNA, C1 - 11 of 15 pts (73.3%) and C2 - 8 of 10 pts (80%). ctDNA levels peaked a median of 2.2 hours (interquartile range (IQR): 1.5 - 2.9 hours) after the initiation of chemotherapy and a median of 1 day (IQR: 1-2 days) after radiation was commenced. The percentage increase in ctDNA levels was a median of 39.3% (IQR: -20.5 to +112.8%) in C1, with median increases of 22.0% and 39.3% in C1a and C1b, respectively. C2 had a median increase of 81.9% (IQR: 0 to +161.5%).

Conclusion: ctDNA levels increase in the hours to days after starting a new treatment. ctDNA testing in the acute post treatment phase can yield results that were not evident in pretreatment testing. Application of this principle could improve ctDNA utility as an alternate to tissue-based testing and/or improve sensitivity for the detection of treatment-resistant clones.

Citation Format: Daniel Breadner, Mark David Vincent, Rohann Correa, Morgan Black, Andrew Warner, Melody Qu, Diane Logan, Michael Sanatani, Jawaid Younus, Brian Yaremko, George Rodrigues, Phillip Blanchette, Joanna Laba, Edward Yu, David Goodale, Lori Lowes, Vasudeva Bhat, Albert Gratton, James Sinfield, Susan Archer, Clive Morris, Emma Green, Greg Jones, Alison Allan, David Palma, Jacques Raphael. Exploitation of treatment induced tumor lysis to enhance sensitivity of ctDNA analysis: a first-in-human pilot study [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 770.

Efficacy and safety of ALK inhibitors in ALK-rearranged non-small cell lung cancer: A systematic review and meta-analysis

OBJECTIVES

No overall survival (OS) benefit has been reported from a mature randomized trial with the use of ALK inhibitors. We conducted a systematic review and meta-analysis to assess the efficacy of ALK inhibitors compared to chemotherapy (ALK vs. chemo) and 2nd generation ALK inhibitors compared to 1 st generation ALK inhibitors (ALK-2 G vs. ALK-1 G).

METHODS

The electronic databases Medline (PubMed), EMBASE, and the Cochrane Database of Systematic Reviews were searched for relevant randomized trials. Pooled hazard ratios (HR) for OS and progression free survival (PFS), and pooled risk ratios for objective response rates (ORR) and toxicity were meta-analyzed using the generic inverse variance and the Mantel-Haenszel methods. To account for between-studies heterogeneity, random-effect models were used. Subgroup analyses compared PFS by gender, smoking status, brain metastases, race and age.

RESULTS

Six trials were included in the analysis of ALK vs. chemo and four in the analysis of ALK-2 G vs. ALK-1 G. Treatment with ALK inhibitors improved OS compared to chemotherapy (HR: 0.84, 95 %CI 0.72-0.97) while a trend toward a better OS was seen with ALK-2 G vs. ALK-1 G (HR: 0.66, 95 %CI 0.43-1.02). PFS was improved with ALK vs. chemo and ALK-2 G vs. ALK-1 G (HR: 0.44, 95 %CI 0.35-0.54 and HR: 0.38, 95 %CI-0.29-0.51, respectively). ORR was improved with ALK vs. chemo and ALK-2 G vs. ALK-1 G. No difference in toxicity was observed.

CONCLUSIONS

This meta-analysis is the first, to our knowledge, to report an OS and PFS benefit with the use of ALK inhibitors compared to chemotherapy from randomized trial data. A trend toward a better OS was also seen with ALK-2 G vs. ALK-1 G and this is likely because of crossover effects and limited OS follow-up. Longer follow up and further research are warranted to directly compare ALK inhibitor sequences and to understand the outcomes of second generation ALK inhibitors as initial therapy.

Abstract P3-11-01: An updated systematic review and meta-analysis of the safety and efficacy of phosphoinositide 3-kinase inhibitors (PI3Ki) in advanced breast cancer

Background In advanced breast cancer (ABC), the addition of pan-PI3Ki to the standard of care (SOC) treatment improves tumor response rate and progression free survival (PFS). Yet, further development of these drugs has been limited by their safety profile. Instead, selective PI3Ki were assessed and the Food and Drug Administration has recently approved the use of a selective PI3Ki based on a phase 3 randomized trial. Therefore, we updated our systematic review and meta-analysis to evaluate whether there is a difference in the efficacy and/or safety of pan versus selective PI3Ki in ABC. Methods The electronic databases Ovid PubMed, Cochrane Central Register of Controlled Trials and Embase, were searched for relevant publications reporting randomized controlled trials between January 2000 and June 2019. Pooled hazard ratios (HR) for progression-free survival (PFS), and pooled odds ratios (OR) for objective response rate (ORR), disease control rate (DCR) and toxicity were computed and weighted using Mantel-Haenszel method and generic inverse variance. Subgroup analyses compared patients with and without PI3K pathway activation. Results Seven studies comprising 3,597 patients were included (5 studies with pan-PI3Ki and 2 studies with selective PI3Ki). Pan and selective PI3Ki decreased the risk of progression by 21% and 32% compared to SOC: HR: 0.79, 95%CI 0.0.71-0.88 and 0.68, 95%CI 0.57-0.81 respectively, p for test for subgroup differences: 0.16. An improvement in ORR was more pronounced with the use of selective versus pan PI3Ki: OR 2.67, 95%CI 1.78-4.00 and OR 1.31, 95%CI 1.01-1.71 respectively, p for test for subgroup differences: 0.004 and DCR was only improved with selective PI3Ki: OR 1.85 95%CI 1.37-2.51. A statistically significant increase in the toxicity of any grade and of grade 3 and higher was observed with pan and selective PI3Ki: 1) for any grade toxicity: OR 5.51, 95%CI 3.05-9.96, and OR 3.77, 95%CI 2.16-6.58 respectively, p for test for subgroup differences 0.16; 2) for grade 3 or higher toxicity: OR 1.91, 95%CI 1.76-2.08 and OR 2.41, 95%CI 2.07-2.82 respectively; p for test for subgroup difference 0.01. In subgroup analyses, the PFS improvement was more pronounced in the PI3K mutant subgroup: HR 0.72, 95%CI 0.63-81 for the PI3K mutant subgroup and HR 0.83, 95%CI 0.73-0.96 for the PI3K wild-type subgroup, p for test for subgroup differences 0.11. Conclusion While selective PI3Ki have a better effect on ORR, DCR and PFS in patients with ABC compared to pan PI3Ki; their toxicity profile is still clinically substantial. Rigorous safety monitoring and early medical intervention are needed to reduce treatment discontinuation, optimize efficacy and render these drugs more clinically usable.

Citation Format: Jacques Raphael, Syed Hussaini, Kathleen I Pritchard, Prakesh Shah, Phillip Blanchette, Ricardo Fernandes, Danielle Desautels. An updated systematic review and meta-analysis of the safety and efficacy of phosphoinositide 3-kinase inhibitors (PI3Ki) in advanced breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-11-01.

Predictors of Survival Benefit From Immune Checkpoint Inhibitors in Patients With Advanced Non-small-cell Lung Cancer: A Systematic Review and Meta-analysis

Randomized trials showed inconsistent survival benefit with immune checkpoint inhibitors (ICIs) in patients with advanced non-small-cell lung cancer with low programmed death-ligand 1 (PD-L1) tumors (< 1%) and in elderly patients (> 65 years old) and never-smokers. We conducted a systematic review and meta-analysis to assess the efficacy of single agent ICIs in these pre-defined subgroups. The electronic databases PubMed and EMBASE were searched for relevant randomized trials. Pooled hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) were meta-analyzed using the generic inverse variance method. Nine studies were included. Compared with chemotherapy, the use of single agent ICIs in the second-line setting reduced the risk of death independent of PD-L1 expression (HR, 0.79; 95% confidence interval [CI], 0.66-0.96 and HR, 0.75; 95% CI, 0.61-0.85 for patients with PD-L1-negative and -positive tumors, respectively). Yet, a PFS benefit was only seen in patients with PD-L1-positive tumors. Similarly, an OS benefit was seen in patients independent of age (HR, 0.79; 95% CI, 0.69-0.89 and HR, 0.76; 95% CI, 0.66-0.88 for elderly and non-elderly patients, respectively). Conversely, an OS benefit was only seen in ever-smokers (HR, 0.78; 95% CI, 0.68-0.89) and a detrimental effect on PFS in never-smokers (HR, 1.68; 95% CI, 1.07-2.63). Patients with advanced non-small-cell lung cancer derive a survival benefit from ICIs independent of tumor PD-L1 expression and age, particularly in the second line, whereas never-smokers do not. Caution should be exercised when offering single-agent ICIs to elderly patients in the first line, and other treatment options should be considered in never-smokers.

Cost-effectiveness analysis of multigene expression profiling assays to guide adjuvant therapy decisions in women with invasive early-stage breast cancer

Gene expression profiling (GEP) testing using 12-gene recurrence score (RS) assay (EndoPredict®), 58-gene RS assay (Prosigna®), and 21-gene RS assay (Oncotype DX®) is available to aid in chemotherapy decision-making when traditional clinicopathological predictors are insufficient to accurately determine recurrence risk in women with axillary lymph node-negative, hormone receptor-positive, and human epidermal growth factor-receptor 2-negative early-stage breast cancer. We examined the cost-effectiveness of incorporating these assays into standard practice. A decision model was built to project lifetime clinical and economic consequences of different adjuvant treatment-guiding strategies. The model was parameterized using follow-up data from a secondary analysis of the Anastrozole or Tamoxifen Alone or Combined randomized trial, cost data (2017 Canadian dollars) from the London Regional Cancer Program (Canada) and secondary Canadian sources. The 12-gene, 58-gene, and 21-gene RS assays were associated with cost-effectiveness ratios of $36,274, $48,525, and $74,911/quality-adjusted life year (QALY) gained and resulted in total gains of 379, 284.3, and 189.5 QALYs/year and total budgets of $12.9, $14.2, and $16.6 million/year, respectively. The total expected-value of perfect information about GEP assays' utility was $10.4 million/year. GEP testing using any of these assays is likely clinically and economically attractive. The 12-gene and 58-gene RS assays may improve the cost-effectiveness of GEP testing and offer higher value for money, although prospective evidence is still needed. Comparative field evaluations of GEP assays in real-world practice are associated with a large societal benefit and warranted to determine the optimal and most cost-effective assay for routine use.

Filgrastim use in patients receiving chemotherapy for early-stage breast cancer-a survey of physicians and patients

PURPOSE

Despite its widespread use as primary febrile neutropenia (FN) prophylaxis during chemotherapy for early-stage breast cancer, the optimal duration of daily filgrastim is unknown. Using the minimum effective duration may improve patient comfort and acceptability while reducing costs. Yet, suboptimal dosing may also negatively impact patient care. A survey was performed to obtain information regarding current practices for granulocyte colony-stimulating factor (G-CSF) use.

METHODS

Canadian oncologists involved in the treatment of breast cancer patients, as well as patients who had received neo/adjuvant chemotherapy for breast cancer, were surveyed. Standardized surveys were designed to collect information on perceived reasons for G-CSF use and current practices.

RESULTS

The surveys were completed by 38/50 (76%) physicians and 95/97 (98%) patients. For physicians, there was variability in the choice of chemotherapy regimens that required G-CSF support, the dose of filgrastim prescribed and the number of days prescribed. The majority of physicians reported using 5 (31.6%), 7 (47.4%), or 10 (13.2%) days of therapy. Nearly half of the patients (46.3%) recalled having experienced at least one of the chemotherapy-related complications including chemotherapy delays, dose reductions, and FN. While on filgrastim, 66.3% of patients reported myalgia and bone pain. Both physicians and patients expressed interest in participating in clinical trials designed to optimize the duration of filgrastim administration.

CONCLUSIONS

Significant variability in practice exists with respect to filgrastim administration. Definitive studies are therefore required to standardize and improve care, as this has the potential to impact treatment outcomes, patient quality of life, and cost savings.

Case report of very late gastric cancer recurrence

Very late recurrence of gastric cancer is rare. Here, we report a dramatic recurrence of gastric cancer, with isolated skeletal metastasis and bone marrow carcinomatosis, 22 years after the patient's initial presentation. Gastric cancer recurrence involving bone or bone marrow is also uncommon and associated with poor prognosis. Pathology from a bone marrow biopsy showed signet ring cell morphology. The patient in this case demonstrated a surprising response-lasting 11 months-to palliative chemotherapy with cisplatin and capecitabine. This case report and literature review describes the characteristics of late gastric cancer recurrence and an approach to the diagnosis and management of patients with bone metastasis or bone marrow carcinomatosis.

Cross-talk between phosphorylation and SUMOylation regulates transforming activities of an adenoviral oncoprotein

Since the discovery of post-translational modification (PTM) by the small ubiquitin-related modifiers (SUMOs), a multitude of proteins have been described to be reversibly modified, resulting in the alteration of several cellular pathways. Interestingly, various pathogens gain access to this modification system, although the molecular mechanisms and functional consequences are barely understood. We show here that the adenoviral oncoprotein E1B-55K is a substrate of the SUMO conjugation system, which is directly linked to its C-terminal phosphorylation. This regulative connection is indispensable for modulation of the tumor suppressor p53/chromatin-remodeling factor Daxx by E1B-55K and, consequently, its oncogenic potential in primary mammalian cells. In virus infection, E1B-55K PTMs are necessary for localization to viral transcription/replication sites. Furthermore, we identify the E2 enzyme Ubc9 as an interaction partner of E1B-55K, providing a possible molecular explanation for SUMO-dependent modulation of cellular target proteins. In conclusion, these results for the first time provide evidence how E1B-55K PTMs are regulated and subsequently facilitate exploitation of the host cell SUMOylation machinery.

Association of fibrinogen with Parkinson disease in elderly Japanese-American men: a prospective study

BACKGROUND

The purpose of this prospective study was to examine whether fibrinogen level is associated with Parkinson disease (PD) for both prevalent and incident cases.

METHODS

The Honolulu Asia-Aging Study is a longitudinal study of Japanese-American men based on the Honolulu Heart Study birth cohort. The original cohort consisted of 8,006 participants with selective service records who were living on the island of Oahu, Hawaii, in 1965. For this analysis, baseline was defined as the 1991-1993 examination (n = 3,845) when men were aged 71-93 years old. Multivariate logistic regression and Cox proportional hazards models were used, adjusting for potential confounders.

RESULTS

We identified 61 prevalent cases and 61 incident cases of PD during the follow-up. High fibrinogen level (presence in the top quintile) was associated with higher frequency of PD for both prevalent (OR = 2.07, 95% CI = 1.10-3.88, p = 0.024) and incident cases (HR = 3.05, 95% CI = 1.34-6.97, p = 0.008) among men aged 76-93 years, after adjusting for age, smoking, and low-density lipoprotein cholesterol.

CONCLUSIONS

These results suggest high fibrinogen level is associated with increased risk of PD among men over 75 years.

Recent developments in meconium and hair testing methods for the confirmation of gestational exposures to alcohol and tobacco smoke

The use of alcohol and tobacco is prevalent among pregnant women despite the well-known adverse effects of these substances imposed on the developing fetus and immense public health education efforts. Confirmation of gestational exposures to these compounds have relied mostly on maternal self-reporting, which is often underestimated because of guilt, embarrassment, and fear of punitive action. The presence of fatty acid ethyl esters in various biological matrices as a result of alcohol consumption initiated the development of neonatal screening tests for these emerging biological markers in meconium and hair. The levels of nicotine and cotinine in hair have long been used as objective indices for the quantification of exposure to active and passive smoking. Maternal segmental hair analysis in the study of pharmacokinetic changes in nicotine metabolism in the obstetric population is a novel application of this traditional analytical method. The latest developments and novel applications of meconium and hair testing for the confirmation of prenatal alcohol and tobacco exposure are discussed in this review.

A survey of factor prophylaxis in the Canadian haemophilia A population

High-dose factor prophylaxis, defined as the infusion of 25-40 factor (F) VIII International Units (IU) kg bodyweight (bw)(-1)> or = x 3 per week, started at age 1-2 years of life in boys with severe haemophilia A prevents the development of significant bleed-related arthropathy. However, programmes of prophylaxis are very expensive and venous access is a challenge. To ascertain patterns of prophylaxis in Canada during the period of a global shortage of recombinant FVIII concentrate a survey was conducted in 2001. The response rate was 83% and the survey identified 247 inhibitor-negative haemophilia A cases receiving prophylaxis, defined as the regular administration of FVIII at least once weekly, from 14 Canadian haemophilia treatment centres. The median age of the group identified was 13 years (range: 1-65) and 95% of cases had severe haemophilia A defined by a circulating factor level of <1%. The median FVIII infusion dose was 26 (range: 16-33) IU kg(-1); infusions were administered > or = x 3 per week in 67% of cases. High-dose factor prophylaxis was used most frequently in boys <5 years of age (23 of 28 cases, 82%) as compared with 56% (56 of 100), 66% (40 of 61) and 62% (36 of 58) of males ages 5-12, 13-18 and >18 years. Prophylaxis accounted for 50% of the annual Canadian FVIII consumption and was a major driving force in the 10% increase (=19.3 million FVIII IU) in the FVIII consumption in Canada in the 4-year period 1999-2003. Given the economic implications of increased use of prophylaxis prospective studies are warranted to better define optimal prophylaxis regimens in the haemophilia A population.

Assessing nicotine metabolism in pregnancy—a novel approach using hair analysis

Nicotine and its metabolite cotinine are important biochemical markers to determine active or passive exposure to cigarette smoke. The amount of nicotine and cotinine in hair provides a cumulative index of tobacco exposure. This study uses segmental hair analysis to assess changes in nicotine metabolism in a cohort of pregnant women who smoked steadily during the whole gestational period according to their self-report. Maternal hair was collected at the time of delivery and sectioned into segments representing the three trimesters of pregnancy. The concentrations of nicotine and cotinine in each section of hair were measured by radioimmunoassay. Hair concentration of nicotine decreased during pregnancy without any reported reduction in smoking, while the cotinine concentration remained constant. The nicotine-cotinine ratio in these consistent smokers was: 1st trimester 20.6, 2nd trimester 19.9, and 3rd trimester 13.3. These findings are consistent with results from other studies showing increased nicotine metabolism during pregnancy. Our data suggest that the results of segmental hair analysis should be carefully examined in pregnancy. Both nicotine and cotinine levels should be evaluated in order to confirm any significant change in maternal tobacco exposure during pregnancy.

Desmopressin (DDAVP) responsiveness in children with von Willebrand disease

PURPOSE

To determine the pattern and predictors of response to desmopressin (DDAVP) in children with von Willebrand disease (VWD).

METHODS

The authors reviewed the hospital records of all children with type 1 (n = 70) and type 2A (n = 5) VWD who were followed in the institution's Bleeding Disorders Clinic from January 1989 to June 2001 and who had a DDAVP challenge test after diagnosis. The major outcome evaluated was response to DDAVP, defined as an increase of greater than twofold over baseline of von Willebrand factor, ristocetin cofactor (VWF:RCo), and factor VIII coagulant (FVIII:C) and levels above 0.3 IU/mL.

RESULTS

Response to DDAVP was observed in 56 (80%) of the 70 children with type 1 VWD. Age and baseline VWF:RCo and FVIII:C levels were positively associated with DDAVP response. A total of 36 children (28 responders, 8 nonresponders) with type 1 VWD were treated for bleeding episodes or for prophylaxis; of these 75% (6/8) of the nonresponders compared with 7% (2/28) of the responders to a DDAVP challenge test received blood component therapy (P < 0.01). One of the five children with type 2A VWD responded to DDAVP.

CONCLUSIONS

DDAVP challenge tests are recommended in children with newly diagnosed VWD to identify responders in whom DDAVP may be used for the prevention or treatment of bleeding, thus avoiding exposure to blood products. The association of DDAVP response with age merits further investigation.

Degradation of p53 by adenovirus E4orf6 and E1B55K proteins occurs via a novel mechanism involving a Cullin-containing complex

Although MDM2 plays a major role in regulating the stability of the p53 tumor suppressor protein, other poorly understood MDM2-independent pathways also exist. Human adenoviruses have evolved strategies to regulate p53 function and stability to permit efficient viral replication. One mechanism involves adenovirus E1B55K and E4orf6 proteins, which collaborate to target p53 for degradation. To determine the mechanism of this process, a multiprotein E4orf6-associated complex was purified and shown to contain a novel Cullin-containing E3 ubiquitin ligase that is (1) composed of Cullin family member Cul5, Elongins B and C, and the RING-H2 finger protein Rbx1(ROC1); (2) remarkably similar to the von Hippel-Lindau tumor suppressor and SCF (Skp1-Cul1/Cdc53-F-box) E3 ubiquitin ligase complexes; and (3) capable of stimulating ubiquitination of p53 in vitro in the presence of E1/E2 ubiquitin-activating and -conjugating enzymes. Cullins are activated by NEDD8 modification; therefore, to determine whether Cullin complexes are required for adenovirus-induced p53 degradation, studies were conducted in ts41 Chinese hamster ovary cells that are temperature sensitive for the NEDD8 pathway. E4orf6/E1B55K failed to induce the degradation of p53 at the nonpermissive temperature. Thus, our results identify a novel role for the Cullin-based machinery in regulation of p53.

Association of UNP, a ubiquitin-specific protease, with the pocket proteins pRb, p107 and p130

The murine Unp gene encodes a widely expressed ubiquitin-specific protease. The predicted sequence of the UNP protein features motifs common to viral oncoproteins through which these proteins interact with the retinoblastoma gene product pRb, as well as the related 'pocket proteins' p107 and p130. We have explored the possibility that UNP interacts with pocket proteins, and report here that such associations can be detected in vitro and in cells. Associations of UNP and pocket proteins are sensitive to site-directed mutations in a manner directly analogous to those documented in viral oncoproteins. We conclude that within cells UNP does physically associate with pRb, and can also associate with p107 and p130.

Postural hypertension in elderly men--the Honolulu Heart Program

Postural hypertension is a condition in which the blood pressure rises abnormally during standing. The aim of this study is to determine the prevalence of postural hypertension and its association with morbidity and subsequent mortality. At the fourth examination (1991-1993) of the Honolulu Heart Program longitudinal cohort, 3741 Japanese-American men aged 71-93 were examined. Prevalence of postural hypertension in this cohort was 39%. Although there was a high prevalence of postural hypertension in this cohort, its clinical significance is questionable as there were no significant correlations with morbidity and subsequent mortality.

Levodopa-induced dyskinesia: facts and fancy. What does the MPTP monkey model tell us?

Levodopa-induced dyskinesia, one of the most frequent long-term side effects of antiparkinsonian therapy, is often attributed to denervation supersensitivity of dopamine receptors and perhaps more specifically the D-1 receptor. The available evidence based not only on clinico-pathological studies in patients but also on results of experiments performed on methyl-phenyl-tetrahydropyridine (MPTP)-treated monkeys suggests that the mechanisms may be more complex than heretofore believed. Thus it appears that no single receptor is the sole culprit, that some form of denervation supersensitivity is probably involved but not in the form of increased density of dopamine receptors. Moreover, other neurotransmitter systems must be considered such as GABA, excitatory aminoacids and peptides. The MPTP monkey model remains very useful for predicting the potential of new drugs for inducing dyskinesia. Such trials however must be performed in drug-naive animals.