Programmed Death Ligand-1 and Tumor Mutation Burden Testing of Patients With Lung Cancer for Selection of Immune Checkpoint Inhibitor Therapies: Guideline From the College of American Pathologists, Association for Molecular Pathology, International Association for the Study of Lung Cancer, Pulmonary Pathology Society, and LUNGevity Foundation.

CONTEXT.­: Rapid advancements in the understanding and manipulation of tumor-immune interactions have led to the approval of immune therapies for patients with non-small cell lung cancer. Certain immune checkpoint inhibitor therapies require the use of companion diagnostics, but methodologic variability has led to uncertainty around test selection and implementation in practice. OBJECTIVE.­: To develop evidence-based guideline recommendations for the testing of immunotherapy/immunomodulatory biomarkers, including programmed death ligand-1 (PD-L1) and tumor mutation burden (TMB), in patients with lung cancer. DESIGN.­: The College of American Pathologists convened a panel of experts in non-small cell lung cancer and biomarker testing to develop evidence-based recommendations in accordance with the standards for trustworthy clinical practice guidelines established by the National Academy of Medicine. A systematic literature review was conducted to address 8 key questions. Using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach, recommendations were created from the available evidence, certainty of that evidence, and key judgments as defined in the GRADE Evidence to Decision framework. RESULTS.­: Six recommendation statements were developed. CONCLUSIONS.­: This guideline summarizes the current understanding and hurdles associated with the use of PD-L1 expression and TMB testing for immune checkpoint inhibitor therapy selection in patients with advanced non-small cell lung cancer and presents evidence-based recommendations for PD-L1 and TMB testing in the clinical setting.

A Phase II Trial of Pevonedistat and Docetaxel in Patients With Previously Treated Advanced Non-Small-Cell Lung Cancer.

BACKGROUND: Postimmunotherapy (IO) treatment options for stage IV non-small-cell lung cancer (NSCLC) remain limited. Docetaxel alone or in combination with ramucirumab remains a standard of care, but response rates and survival benefit are suboptimal. Cullin-RING ligases (CRL) catalyze degradation of tumor suppressor proteins and are overactivated in NSCLC. Neddylation, which is catalyzed by the NEDD8 activating enzyme (NAE), is required for the activation of CRLs. Pevonedistat, a first-in-class small molecule NAE inhibitor, exerted antitumor activity when combined with docetaxel in preclinical studies. METHODS: We conducted a phase II, single-arm, investigator-initiated study evaluating the efficacy of pevonedistat plus docetaxel in patients with relapsed/refractory stage IV NSCLC. Patients received docetaxel 75 mg/m2 on day 1 and pevonedistat 25 mg/m2 on days 1, 3 and 5 of a 21-day cycle. The primary endpoint was objective response rate (ORR). RESULTS: From March 5, 2018 to January 26, 2021, we enrolled 31 patients. The ORR was 22% (1 CR, 5 PR), median PFS was 4.1 months, and median OS was 13.2 months. The incidence of Grade ≥3 adverse events (AE) was 53% in patients (n = 30) who received at least 1 dose of both drugs, with the most frequent being neutropenia and AST/ALT elevation. One patient was taken off study for a Grade 4 transaminase elevation. There were no Grade 5 toxicities. CONCLUSION: Our data suggest that the combination of docetaxel and pevonedistat is safe and exerts activity in patients with relapsed NSCLC. These encouraging results suggest that the neddylation pathway is an antitumor pathway that should be further studied.

Pralsetinib in patients with RET fusion-positive non-small-cell lung cancer: A plain language summary of the ARROW study.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of a research study called ARROW, which tested a medicine called pralsetinib in patients with non-small cell lung cancer (NSCLC), thyroid cancer, and other advanced solid tumours caused by a change in a gene called RET. For the purposes of this summary, only patients with NSCLC with a change in RET called fusion (RET fusion+) are highlighted. WHAT WERE THE RESULTS?: In total, 281 patients with RET fusion+ NSCLC had taken part in this study across the USA, Europe, and Asia. Patients were asked to take four pills (adding up to 400 mg) of pralsetinib each day and were checked for any changes in their tumours, as well as for any side effects. After an average of 8 months of treatment with pralsetinib, 72% of previously untreated patients and 59% of patients who had previously received chemotherapy had considerable shrinkage of their tumours. Among 10 patients with tumours which had spread to the brain (all of whom had received previous treatments), 70% had their tumours shrink greatly in the brain after treatment with pralsetinib. On average, patients lived with little to no tumour growth for 16 months. In previously untreated patients, the most common severe side effects that were considered related to pralsetinib treatment were decreased white blood cells (neutrophils and lymphocytes), increased blood pressure, and an increase in a blood protein called creatine phosphokinase. In previously treated patients, the severe side effects were decreased white blood cells (neutrophils, lymphocytes, and leukocytes), increased blood pressure, and low levels of red blood cells. In both untreated and previously treated patients, the most common severe side effects that required hospital attention were lung inflammation/swelling causing shortness of breath (pneumonitis) and lung infection (pneumonia). WHAT DO THE RESULTS MEAN?: Overall, the ARROW study showed that pralsetinib was effective in shrinking tumours in patients with RET fusion+ NSCLC regardless of previous treatment history. The recorded side effects were expected in patients receiving this type of medicine. Clinical Trial Registration: NCT03037385 (ARROW) (ClinicalTrials.gov).

Patient-Reported Health-Related Quality of Life in KEYNOTE-604: Pembrolizumab or Placebo Added to Etoposide and Platinum as First-Line Therapy for Extensive-Stage SCLC.

Introduction: In the phase 3 KEYNOTE-604 study (NCT03066778), pembrolizumab plus etoposide and platinum chemotherapy (EP) significantly (p = 0.0023) improved progression-free survival versus placebo plus EP in previously untreated extensive-stage SCLC (ES-SCLC). We present health-related quality of life (HRQoL) results from KEYNOTE-604. Methods: Patients with stage IV SCLC were randomized 1:1 to pembrolizumab 200 mg or placebo every 3 weeks for 35 cycles plus four cycles of EP. Secondary end points included mean change from baseline to week 18 in the European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire-Core 30 (QLQ-C30) global health status/quality of life (GHS/QoL) scale and time to deterioration in the composite outcome of cough, chest pain, or dyspnea from QLQ-C30 and QLQ-Lung Cancer Module 13. Two-sided, nominal p values are reported. Results: A total of 439 patients completed at least one QLQ-C30 and QLQ-Lung Cancer Module 13 assessment (pembrolizumab + EP, n = 221; placebo + EP, n = 218). GHS/QoL scores improved from baseline to week 18: least squares mean (95% confidence interval [CI]) changes were 8.7 (5.3-12.1) for pembrolizumab plus EP and 4.2 (0.9-7.5) for placebo plus EP. Between-group differences in least squares mean scores were improved for pembrolizumab plus EP (4.4 [95% CI: 0.2-8.7], p = 0.040]). Median time to deterioration for the composite end point was not reached and 8.7 (95% CI: 5.9-not reached) months, respectively (hazard ratio = 0.80 [95% CI: 0.56-1.14], p = 0.208). Conclusions: First-line pembrolizumab plus EP therapy maintained HRQoL in patients with ES-SCLC and may be associated with greater improvement than placebo plus EP. Together with the efficacy and safety findings in KEYNOTE-604, HRQoL data support the benefit of pembrolizumab in ES-SCLC.

Systemic Therapy for Small-Cell Lung Cancer: ASCO-Ontario Health (Cancer Care Ontario) Guideline.

PURPOSE: To provide evidence-based recommendations to practicing clinicians on the management of patients with small-cell lung cancer. METHODS: An Expert Panel of medical oncology, thoracic surgery, radiation oncology, pulmonary, community oncology, research methodology, and advocacy experts were convened to conduct a literature search, which included systematic reviews, meta-analyses, and randomized controlled trials published from 1990 through 2022. Outcomes of interest included response rates, overall survival, disease-free survival or recurrence-free survival, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations. RESULTS: The literature search identified 95 relevant studies to inform the evidence base for this guideline. RECOMMENDATIONS: Evidence-based recommendations were developed to address systemic therapy options, timing of therapy, treatment in patients who are older or with poor performance status, role of biomarkers, and use of myeloid-supporting agents in patients with small-cell lung cancer.Additional information is available at www.asco.org/thoracic-cancer-guidelines.

An evaluation of sotorasib for the treatment of patients with non-small cell lung cancer with KRASG12C mutations.

INTRODUCTION: Improving the clinical outcomes of patients with KRASG12C-mutated non-small cell lung cancer (NSCLC), the majority of whom are current or former smokers, has been a barrier to improving population-level outcomes in NSCLC. Novel and effective KRASG12C inhibitors are emerging, and sotorasib is the first member of that class to achieve commercial availability. AREAS COVERED: In this review, we survey the epidemiology of KRASG12C-mutated NSCLC, as well as sotorasib's chemistry, pharmacology, and clinical trial data. EXPERT OPINION: While sotorasib's development has been unique and exciting, questions persist regarding its intracranial penetrance, optimal dose, and efficacy relative to standard-of-care therapy. Improvements in the clinical activity of KRAS inhibition will hinge on better understanding of resistance mechanisms, the development of broad-spectrum inhibitors with activity beyond G12C mutations, and combination therapy targeting multiple mediators of KRAS signaling and alternative pathways. From a regulatory perspective, sotorasib's development may, in time, prove to be an instructive example for early-phase clinical trialists and regulators focused on dose optimization.

Pan-cancer efficacy of pralsetinib in patients with RET fusion-positive solid tumors from the phase 1/2 ARROW trial.

Oncogenic RET fusions occur in diverse cancers. Pralsetinib is a potent, selective inhibitor of RET receptor tyrosine kinase. ARROW ( NCT03037385 , ongoing) was designed to evaluate pralsetinib efficacy and safety in patients with advanced RET-altered solid tumors. Twenty-nine patients with 12 different RET fusion-positive solid tumor types, excluding non-small-cell lung cancer and thyroid cancer, who had previously received or were not candidates for standard therapies, were enrolled. The most common RET fusion partners in 23 efficacy-evaluable patients were CCDC6 (26%), KIF5B (26%) and NCOA4 (13%). Overall response rate, the primary endpoint, was 57% (95% confidence interval, 35-77) among these patients. Responses were observed regardless of tumor type or RET fusion partner. Median duration of response, progression-free survival and overall survival were 12 months, 7 months and 14 months, respectively. The most common grade ≥3 treatment-related adverse events were neutropenia (31%) and anemia (14%). These data validate RET as a tissue-agnostic target with sensitivity to RET inhibition, indicating pralsetinib's potential as a well-tolerated treatment option with rapid, robust and durable anti-tumor activity in patients with diverse RET fusion-positive solid tumors.

Cellular engagement and interaction in the tumor microenvironment predict non-response to PD-1/PD-L1 inhibitors in metastatic non-small cell lung cancer.

Immune checkpoint inhibitors (ICI) with anti-PD-1/PD-L1 agents have improved the survival of patients with metastatic non-small cell lung cancer (mNSCLC). Tumor PD-L1 expression is an imperfect biomarker as it does not capture the complex interactions between constituents of the tumor microenvironment (TME). Using multiplex fluorescent immunohistochemistry (mfIHC), we modeled the TME to study the influence of cellular distribution and engagement on response to ICI in mNSCLC. We performed mfIHC on pretreatment tissue from patients with mNSCLC who received ICI. We used primary antibodies against CD3, CD8, CD163, PD-L1, pancytokeratin, and FOXP3; simple and complex phenotyping as well as spatial analyses was performed. We analyzed 68 distinct samples from 52 patients with mNSCLC. Patients were 39-79 years old (median 67); 44% were male and 75% had adenocarcinoma histology. The most used ICI was atezolizumab (48%). The percentage of PD-L1 positive epithelial tumor cells (EC), degree of cytotoxic T lymphocyte (CTL) engagement with EC, and degree of CTL engagement with helper T lymphocytes (HTL) were significantly lower in non-responders versus responders (p = 0.0163, p = 0.0026 and p = 0.0006, respectively). The combination of these 3 characteristics generated the best sensitivity and specificity to predict non-response to ICI and was also associated with shortened overall survival (p = 0.0271). The combination of low CTL engagement with EC and HTL along with low expression of EC PD-L1 represents a state of impaired endogenous immune reactivity. Together, they more precisely identified non-responders to ICI compared to PD-L1 alone and illustrate the importance of cellular interactions in the TME.

Bone Metastases, Skeletal-Related Events, and Survival in Patients With Metastatic Non-Small Cell Lung Cancer Treated With Immune Checkpoint Inhibitors.

BACKGROUND: Bone metastases and skeletal-related events (SREs) are a frequent cause of morbidity in patients with metastatic non-small cell lung cancer (mNSCLC). Data are limited on bone metastases and SREs in patients with mNSCLC treated using immune checkpoint inhibitors (ICIs), and on the efficacy of bone-modifying agents (BMAs) in this setting. Here we report the incidence, impact on survival, risk factors for bone metastases and SREs, and impact of BMAs in patients with mNSCLC treated with ICIs in a multi-institutional cohort. PATIENTS AND METHODS: We conducted a retrospective study of patients with mNSCLC treated with ICIs at 2 tertiary care centers from 2014 through 2017. Overall survival (OS) was compared between patients with and without baseline bone metastases using a log-rank test. A Cox regression model was used to evaluate the association between OS and the presence of bone metastases at ICI initiation, controlling for other confounding factors. RESULTS: We identified a cohort of 330 patients who had received ICIs for metastatic disease. Median patient age was 63 years, most patients were treated in the second line or beyond (n=259; 78%), and nivolumab was the most common ICI (n=211; 64%). Median OS was 10 months (95% CI, 8.4-12.0). In our cohort, 124 patients (38%) had baseline bone metastases, and 43 (13%) developed SREs during or after ICI treatment. Patients with bone metastases had a higher hazard of death after controlling for performance status, histology, line of therapy, and disease burden (hazard ratio, 1.57; 95% CI, 1.19-2.08; P=.001). Use of BMAs was not associated with OS or a decreased risk of SREs. CONCLUSIONS: Presence of bone metastases at baseline was associated with a worse prognosis for patients with mNSCLC treated with ICI after controlling for multiple clinical characteristics. Use of BMAs was not associated with reduced SREs or a difference in survival.

Characterization of pneumonia and other factors leading to poorer survival across all age groups in patients with non-small cell lung cancer (NSCLC).

BACKGROUND: Lung cancer death rates and incidence in both men and women have decreased over the past two decades. However, certain subsets of non-small cell lung cancer (NSCLC) have arisen with poor outcomes. Identifying factors which contribute to poorer outcomes as well as those that inform early detection strategies remain unmet needs. We present data from a contemporaneous group of NSCLC patients that received care at a single University teaching hospital to understand clinical and pathological factors influencing outcomes in the past decade. METHODS: A cohort of 2,289 patients with NSCLC who established care at the Rogel Cancer Center, University of Michigan between January 2011 and April 2019 were identified. Patient characteristics and clinical outcomes were recorded using electronic health records. The Kaplan-Meier method and the Cox proportional model were used to assess relationship between clinic-pathological factors and survival. RESULTS: Of the 2,289 patients, 92% were >50 years of age while 8% were <50 years of age. The majority (70%) of older patients were former smokers. The majority (61%) of younger patients were diagnosed as having Stage IV NSCLC. Among younger patients, 87% had histologically confirmed non-squamous histology. Univariate analysis revealed that overall survival was significantly lower in patients diagnosed with pneumonia prior to the diagnosis of NSCLC than in those who were not diagnosed with pneumonia (1.9 vs. 21.8 months; P<0.001). Multivariate analysis revealed that older patients had poorer survival than younger patients (HR 1.57, 95% CI: 1.10-2.06, P=0.01) and that patients diagnosed with pneumonia prior to their lung cancer diagnosis had poorer survival across all age groups, particularly in those with advanced-stage disease. CONCLUSIONS: Findings from this study merit prospective studies to understand cost-benefit ratio of follow- up cross sectional imaging of all patients diagnosed with unprovoked pneumonia, including in younger non/current smokers.

Emerging drugs for small cell lung cancer: a focused review on immune checkpoint inhibitors.

INTRODUCTION: Small cell lung cancer (SCLC) is an aggressive malignancy that accounts for 15% of all lung cancers. It is characterized by initial responsiveness to therapy followed by rapid disease progression that is relatively resistant to further treatment. Recently, the addition of an immune checkpoint inhibitor (ICI) to chemotherapy has improved survival in patients with advanced disease, the first advance in systemic therapy in SCLC in over 30 years. AREAS COVERED: In this review, we present an overview of SCLC with a focus on the scope of the problem and standard treatment, followed by a critical assessment of scientific rationale for immunotherapy in SCLC and the clinical trials that have been performed with ICIs in SCLC. Finally, we address ongoing hurdles for the development of ICIs in SCLC and potential avenues for further study. EXPERT OPINION: Despite solid biological rationale, the results of clinical trials of ICIs in SCLC have yielded modest benefits. A small subset of patients does achieve long-term benefit, but further development of ICIs in SCLC will depend on the identification of predictive biomarkers and the design of combination regimens that take advantage of the molecular alterations that drive the immune-avoidance mechanisms and survival of SCLC cells.

Pembrolizumab or Placebo Plus Etoposide and Platinum as First-Line Therapy for Extensive-Stage Small-Cell Lung Cancer: Randomized, Double-Blind, Phase III KEYNOTE-604 Study.

PURPOSE: Pembrolizumab monotherapy has shown antitumor activity in patients with small-cell lung cancer (SCLC). The randomized, double-blind, phase III KEYNOTE-604 study compared pembrolizumab plus etoposide and platinum (EP) with placebo plus EP for patients with previously untreated extensive-stage (ES) SCLC. METHODS: Eligible patients were randomly assigned 1:1 to pembrolizumab 200 mg once every 3 weeks or saline placebo for up to 35 cycles plus 4 cycles of EP. Primary end points were progression-free survival (PFS; RECIST version 1.1, blinded central review) and overall survival (OS) in the intention-to-treat population. Objective response rate (ORR) and duration of response were secondary end points. Prespecified efficacy boundaries were one-sided P = .0048 for PFS and .0128 for OS. RESULTS: Of the 453 participants, 228 were randomly assigned to pembrolizumab plus EP and 225 to placebo plus EP. Pembrolizumab plus EP significantly improved PFS (hazard ratio [HR], 0.75; 95% CI, 0.61 to 0.91; P = .0023). Twelve-month PFS estimates were 13.6% with pembrolizumab plus EP and 3.1% with placebo plus EP. Although pembrolizumab plus EP prolonged OS, the significance threshold was not met (HR, 0.80; 95% CI, 0.64 to 0.98; P = .0164). Twenty-four-month OS estimates were 22.5% and 11.2%, respectively. ORR was 70.6% in the pembrolizumab plus EP group and 61.8% in the placebo plus EP group; the estimated proportion of responders remaining in response at 12 months was 19.3% and 3.3%, respectively. In the pembrolizumab plus EP and placebo plus EP groups, respectively, any-cause adverse events were grade 3-4 in 76.7% and 74.9%, grade 5 in 6.3% and 5.4%, and led to discontinuation of any drug in 14.8% and 6.3%. CONCLUSION: Pembrolizumab plus EP significantly improved PFS compared with placebo plus EP as first-line therapy for patients with ES-SCLC. No unexpected toxicities were seen with pembrolizumab plus EP. These data support the benefit of pembrolizumab in ES-SCLC.

Cyclin-dependent kinase inhibitors for the treatment of lung cancer.

INTRODUCTION: Cyclin-dependent kinases (CDKs) are critical regulators of cell cycle progression in both normal and malignant cells, functioning through complex molecular interactions. Deregulation of CDK-dependent pathways is commonly found in both non-small cell and small cell lung cancer, and these derangements suggest vulnerabilities that can be exploited for clinical benefit. AREAS COVERED: In this review, the authors present an overview of the biology of CDKs in normal and malignant cells, with a focus on lung cancer, followed by an assessment of preclinical work that has demonstrated the vital role of CDKs in lung cancer development and progression, and the activity of CDK inhibitors in a variety of lung cancer models. Finally, the experience with clinical trials of CDK inhibitors in lung cancer is discussed along with the current status of these agents in cancer therapy. EXPERT OPINION: Despite strong biological rationale and promising preclinical studies, the results of clinical trials of CDK inhibitors in lung cancer have thus far been disappointing. Further clinical development of CDK inhibitors in lung cancer will depend on the identification of predictive biomarkers and the design of combination regimens that take advantage of the unique molecular alterations that drive lung cancer growth and survival.

High-Throughput Label-Free Isolation of Heterogeneous Circulating Tumor Cells and CTC Clusters from Non-Small-Cell Lung Cancer Patients.

(1) Background: Circulating tumor cell (CTC) clusters are emerging as clinically significant harbingers of metastases in solid organ cancers. Prior to engaging these CTC clusters in animal models of metastases, it is imperative for technology to identify them with high sensitivity. These clusters often present heterogeneous surface markers and current methods for isolation of clusters may fall short. (2) Methods: We applied an inertial microfluidic Labyrinth device for high-throughput, biomarker-independent, size-based isolation of CTCs/CTC clusters from patients with metastatic non-small-cell lung cancer (NSCLC). (3) Results: Using Labyrinth, CTCs (PanCK+/DAPI+/CD45-) were isolated from patients (n = 25). Heterogeneous CTC populations, including CTCs expressing epithelial (EpCAM), mesenchymal (Vimentin) or both markers were detected. CTCs were isolated from 100% of patients (417 ± 1023 CTCs/mL). EpCAM- CTCs were significantly greater than EpCAM+ CTCs. Cell clusters of ≥2 CTCs were observed in 96% of patients-of which, 75% were EpCAM-. CTCs revealed identical genetic aberrations as the primary tumor for RET, ROS1, and ALK genes using fluorescence in situ hybridization (FISH) analysis. (4) Conclusions: The Labyrinth device recovered heterogeneous CTCs in 100% and CTC clusters in 96% of patients with metastatic NSCLC. The majority of recovered CTCs/clusters were EpCAM-, suggesting that these would have been missed using traditional antibody-based capture methods.

Real-world comparison of immune checkpoint inhibitors in non-small cell lung cancer following platinum-based chemotherapy.

PURPOSE: Immunotherapy is a relatively new treatment modality for advanced non-small cell lung cancer following platinum-based chemotherapy. Nivolumab, pembrolizumab, and atezolizumab demonstrated superior outcomes and improved tolerability compared to standard treatment in randomized controlled trials; however, these studies vary significantly in inclusion criteria and study design. To our knowledge, the efficacy and safety of nivolumab and atezolizumab following platinum-based chemotherapy have not been directly compared to one another in a real-world clinic setting. METHODS: We retrospectively compared immunotherapy response rates and toxicity in patients with stage IV or recurrent non-small cell lung cancer following progression during or after platinum-based chemotherapy. RESULTS: Among 124 eligible patients, the objective response rate was 14.8% in the nivolumab group (n = 81) vs. 13.9% in the atezolizumab group (n = 43) (p = 0.897). Median overall survival was 8.4 months with nivolumab (95% confidence interval (CI), 6.3 to 11.2) vs. 6.5 months with atezolizumab (95% CI, 4.7 to not reached). Median progression free survival was 2.2 months (95% CI, 1.7 to 2.8) and 2.0 months (95% CI, 1.8 to 2.7) in the nivolumab and atezolizumab groups, respectively. Treatment-related adverse events occurred in 70.4% of patients in the nivolumab group and 65.1% in the atezolizumab group. CONCLUSIONS: There was no statistically significant difference in efficacy outcomes in patients with non-small cell lung cancer who received atezolizumab or nivolumab after progression during or after platinum-based chemotherapy. Response rates in this study were numerically lower than response rates observed in the landmark randomized controlled trials leading to approval of immunotherapy in this setting. Rates of treatment-related adverse events were similar between groups.

A Pilot Study of Atezolizumab Plus Hypofractionated Image Guided Radiation Therapy for the Treatment of Advanced Non-Small Cell Lung Cancer.

PURPOSE: Preclinical data and subset analyses from immunotherapy clinical trials indicate that prior radiation therapy was associated with better progression-free survival and overall survival when combined with immune checkpoint inhibitors in patients with non-small cell lung cancer. We present a prospective study of hypofractionated image guided radiation therapy (HIGRT) to a single site of metastatic disease concurrently with atezolizumab in patients with metastatic non-small cell lung cancer. METHODS AND MATERIALS: Patients meeting eligibility criteria received 1200 mg of atezolizumab intravenously every 3 weeks with concurrent 3- or 5-fraction HIGRT starting no later than the second cycle. The 3-fraction regimen employed a minimum of 8 Gy per fraction compared with 6 Gy for the 5-fraction regimen. Imaging was obtained every 12 weeks to assess response. RESULTS: From October 2015 to February 2017, 12 patients were enrolled in the study (median age 64; range, 55-77 years). The best response by the Response Evaluation in Solid Tumors criteria was partial response in 3 and stable disease in 3, for a disease control rate of 50%. Five patients had a grade 3 immune-related adverse event, including choreoretinitis (n = 1), pneumonitis (n = 1), transaminitis (n = 1), fatigue (n = 1), and peripheral neuropathy (n = 1). The median progression-free survival was 2.3 months, and the median overall survival was 6.9 months (range, 0.4-not reached). There was no clear association between peripheral blood T cell repertoire characteristics at baseline, PD-L1, or tumor mutations and response or outcome. One long-term survivor exhibited oligoclonal T cell populations in a baseline tumor biopsy that were consistently detected in peripheral blood over the entire course of the study. CONCLUSIONS: HIGRT plus atezolizumab resulted in an overall response rate of 25% and disease control rate of 50% in this pilot study. The incidence of grade 3 adverse events was similar to that of atezolizumab alone. Alhough it was a pilot study with limited sample size, the results generated hypotheses worthy of further investigation.

Circulating microRNAs as biomarkers of radiation-induced cardiac toxicity in non-small-cell lung cancer.

PURPOSE: Radiation-induced cardiac toxicity (RICT) is an increasingly well-appreciated source of morbidity and mortality in patients receiving thoracic radiotherapy (RT). Currently available methods to predict RICT are suboptimal. We investigated circulating microRNAs (c-miRNAs) as potential biomarkers of RICT in patients undergoing definitive RT for non-small-cell lung cancer (NSCLC). METHODS: Data from 63 patients treated on institutional trials were analyzed. Prognostic models of grade 3 or greater (G3 +) RICT based on pre-treatment c-miRNA levels ('c-miRNA'), mean heart dose (MHD) and pre-existing cardiac disease (PCD) ('clinical'), and a combination of these ('c-miRNA + clinical') were developed. Elastic net Cox regression and full cross validation were used for variable selection, model building, and model evaluation. Concordance statistic (c-index) and integrated Brier score (IBS) were used to evaluate model performance. RESULTS: MHD, PCD, and serum levels of 14 c-miRNA species were identified as jointly prognostic for G3 + RICT. The 'c-miRNA and 'clinical' models yielded similar cross-validated c-indices (0.70 and 0.72, respectively) and IBSs (0.26 and 0.28, respectively). However, prognostication was not improved by combining c-miRNA and clinical factors (c-index 0.70, IBS 0.28). The 'c-miRNA' and 'clinical' models were able to significantly stratify patients into high- and low-risk groups of developing G3 + RICT. Chi-square testing demonstrated a marginally significantly higher prevalence of PCD in patients with high- compared to low-risk c-miRNA profile (p = 0.09), suggesting an association between some c-miRNAs and PCD. CONCLUSIONS: We identified a pre-treatment c-miRNA signature prognostic for G3 + RICT. With further development, pre- and mid-treatment c-miRNA profiling could contribute to patient-specific dose selection and treatment adaptation.

Doses of radiation to the pericardium, instead of heart, are significant for survival in patients with non-small cell lung cancer.

BACKGROUND AND PURPOSE: Higher cardiac dose was associated with worse overall survival in the RTOG0617 study. Pericardial effusion (PCE) is a common cardiac complication of thoracic radiation therapy (RT). We investigated whether doses of radiation to the heart and pericardium are associated with PCE and overall survival in patients treated with thoracic radiation for non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: A total of 94 patients with medically inoperable/unresectable NSCLC treated with definitive RT in prospective studies were reviewed for this secondary analysis. Heart and pericardium were contoured consistently according to the RTOG1106 Atlas, with the great vessels and thymus of the upper mediastinal structures included in the upper part of pericardium, only heart chambers included in the heart structure. Clinical factors and dose-volume parameters associated with PCE or survival were identified via Cox proportional hazards modeling. The risk of PCE and death were mapped using DVH atlases. RESULTS: Median follow-up for surviving patients was 58 months. The overall rate of PCE was 40.4%. On multivariable analysis, dosimetric factors of heart and pericardium were significantly associated with the risk of PCE. Pericardial V30 and V55 were significantly correlated with overall survival, but presence of PCE and heart dosimetric factors were not. CONCLUSION: PCE was associated with both heart and pericardial doses. The significance of pericardial dosimetric parameters, but not heart chamber parameters, on survival suggests the potential significance of radiation damage to the cranial region of pericardium.