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).

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.

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.

An evaluation of sotorasib for the treatment of patients with non-small cell lung cancer with KRAS G12C mutations

INTRODUCTION

Improving the clinical outcomes of patients with KRAS^G12C-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, effective KRAS^G12C 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 KRAS^G12C-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.

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.

Abstract B45: High-throughput label-free isolation and expansion of circulating tumor cells (CTCs) from non-small cell lung cancer (NSCLC) patients for personalized treatments

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.

Methods: We have applied the inertial microfluidic Labyrinth device for high-throughput, biomarker-independent, size-based isolation of CTCs and CTC clusters from patients with metastatic non-small cell lung cancer (NSCLC).

Results: Using the Labyrinth device, CTCs (PanCK+/DAPI+/CD45-) were isolated from metastatic NSCLC patients (n=25). Heterogeneous CTC populations were detected, including CTCs expressing epithelial (EpCAM), mesenchymal (vimentin), or both markers. CTCs were isolated from 100% of patients (417±1023 CTCs/mL), and CTCs that were EpCAM negative were significantly higher in numbers than EpCAM+ CTCs. Cell clusters of ≥2 CTCs were observed in 96% of patients, of which 75% were negative for EpCAM. Patients with higher number of CTC clusters than single CTCs had worse progression-free survival (PFS) (p=0.05). Recovered CTCs from patients with RET, ROS1, and ALK-rearranged tumors revealed identical genetic aberrations as the primary tumor for each gene using FISH analysis. We have successfully expanded the recovered CTCs from 2 patients and screened for therapeutic targeting. We have found that TPX-0005 might be effective in these patients and would direct them to a clinical trial using this compound.

Conclusions: The label-free Labyrinth device demonstrated the capability of collecting recovered CTCs from the device using a continuous processing technique while in a suspension state. This advantage opens the opportunities not only for CTC expansion off-chip, but also for ex vivo drug testing to direct patient-specific therapies.

Citation Format: Mina Zeinali, Wei Huang, Maggie Lee, Arthi Nadhan, Anvya Mathur, Casey Hedman, Eric Lin, Ramdane Harouaka, Max S. Wicha, Lili Zhao, Nallasivam Palanisamy, Mathias Hafner, Rishindra Reddy, Gregory P. Kalemkerian, Bryan J. Schneider, Khaled A. Hassan, Nithya Ramnath, Sunitha Nagrath. High-throughput label-free isolation and expansion of circulating tumor cells (CTCs) from non-small cell lung cancer (NSCLC) patients for personalized treatments [abstract]. In: Proceedings of the AACR Special Conference on Advances in Liquid Biopsies; Jan 13-16, 2020; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(11_Suppl):Abstract nr B45.

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.

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.

NCCN Guidelines Insights: Small Cell Lung Cancer, Version 2.2018

The NCCN Guidelines for Small Cell Lung Cancer (SCLC) address all aspects of disease management. These NCCN Guidelines Insights focus on recent updates to the NCCN Guidelines for SCLC regarding immunotherapy, systemic therapy, and radiation therapy. For the 2018 update, new sections were added on "Signs and Symptoms of SCLC" and "Principles of Pathologic Review."

NCCN Guidelines Insights: Neuroendocrine and Adrenal Tumors, Version 2.2018

The NCCN Guidelines for Neuroendocrine and Adrenal Tumors provide recommendations for the management of adult patients with neuroendocrine tumors (NETs), adrenal gland tumors, pheochromocytomas, and paragangliomas. Management of NETs relies heavily on the site of the primary NET. These NCCN Guidelines Insights summarize the management options and the 2018 updates to the guidelines for locoregional advanced disease, and/or distant metastasis originating from gastrointestinal tract, bronchopulmonary, and thymus primary NETs.

Abstract 931: The T790M mutation is acquired through 5-methylcytosine deamination after EGFR TKI treatment in lung cancer

Background: Epidermal growth factor receptor (EGFR) activation mutations occur in 10-50% of lung adenocarcinomas. EGFR tyrosine kinase inhibitors (TKIs) are the mainstay of treatment for stage IV non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, acquired EGFR mutations are the main mechanism of on-target resistance to TKIs. T790M mutation that occurs after first generation TKI treatment, is a cytosine to thymine (C&gt;T) single nucleotide transition leading to a threonine to methionine amino acid change at position 790 (i.e. T790M). Our data suggest that resistant mutations are acquired events secondary to cytosine deamination through Activation Induced Cytosine Deamination enzyme (AICDA). Interestingly, treatment with Osimertinib, that overcomes the T790M mutation, leads to other acquired resistant mutations (C797S, G796S/R and L792F/H) that are mostly cytosine based.

Results: Sub clones of the lung adenocarcinoma cell line PC9 with no evidence of T790M mutation by digital droplet PCR (ddPCR) at baseline, were treated with EGFR TKI. After serially increasing the treatment dose, T790M mutation was detected by ddPCR associated with a significant increase in AICDA expression. Similarly, when the resistant T790M PC9 clones were treated with Osimertinib, the expression of AICDA was also induced. Knocking down AICDA by shRNA or CRISPR-Cas9, decreases the development of T790M in PC9 cell lines after TKI exposure. Using mass spectrometry, we established that cytosine at codon 790 is methylated; thus, deamination of 5-methylcytosine leads to thymine directly, explaining the T790M C&gt;T mutation. In addition, using ChIP assay and pharmacological inhibition we confirm that upon TKI exposure, NFκB binds AICDA promoter and induces its expression. In a mouse xenograft model, the induction of NFκB and AICDA after EGFR TKI exposure is abrogated by concurrent use of an NFκB inhibitor. Finally, patients treated with EFR TKI had an increased expression of AICDA upon progression.

Conclusion: In EGFR driven lung adenocarcinoma, NFκB pathway is activated upon exposure to EGFR TKIs which induces AICDA expression. AICDA deaminates cytosine into other nucleotides leading to treatment resistance.

Citation Format: Najwa El Kadi, Luo Wang, April Davis, Alexander Cooke, Varun Vadnala, Hasan Korkaya, Gregory P. Kalemkerian, Khaled A. Hassan. The T790M mutation is acquired through 5-methylcytosine deamination after EGFR TKI treatment in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 931.

Abstract 1332: High Throughput isolation and expansion of circulating tumor cells (CTCs) from Non-small cell lung cancer (NSCLC) patients for personalized treatments

Background: Circulating tumor cells (CTCs) have emerged as important blood-based surrogate markers of primary tumors. Current methods for isolation of lung CTCs mostly rely on biomarker dependent antibody-based capture, missing populations that may be stem-like in nature. Results: We have applied the microfluidic Labyrinth device for high throughput, label-free, size-based isolation of CTCs from non-small cell lung cancer patients (NSCLC). The Labyrinth device was optimized and tested for inertial separation of cancer cells using the human lung cancer cell line H1650. The recovery and purity were &gt;82% and &gt;78%, respectively, operating at a flow rate of 2.5 mL/min. Using the biomarker-independent Labyrinth separation device, heterogeneous CTC populations were isolated from metastatic NSCLC patients (n=21). Heterogeneous CTC populations were detected, including CTCs (PanCK+ and CD45-), CTCs expressing EpCAM or Vimentin, and CTCs expressing both markers representing an EMT-like population of CTCs. Using Labyrinth, we were able to isolate CTCs from 100% of patients with an average yield of 180±168 CTCs/mL. Among the captured CTCs, EpCAM- CTCs were significantly more common than EpCAM+ CTCs (115.7 vs. 39.1 CTCs/mL respectively). Cell clusters of 2 or more CTCs were also observed in 95% of patients; 79% of these clusters were negative for EpCAM expression, whereas 35% expressed Vimentin, suggestive of an EMT phenotype. Recovered CTCs from patients with RET, ROS1 and ALK rearranged tumors showed aberrations matching with the primary tumor for each gene using FISH analysis. We have successfully expanded the recovered CTCs from 2 patients and screened for therapeutic targeting. We have found that TPX-0005 might be effective in these patients and would direct them to a clinical trial using this compound. Conclusion: The label-free Labyrinth device demonstrated the capability of collecting recovered CTCs from the device using a continuous processing technique while in a suspension state. This advantage opens the opportunities not only for CTC expansion off-chip, but also for ex-vivo drug testing to direct patient-specific therapies.

Citation Format: Mina Zeinali, Maggie Lee, Arthi Nadhan, Anvya Mathur, Wei Huang, Eric Lin, Ramdane Harouaka, Max S. Wicha, Nallasivam Palanisamy, Mathias Hafner, Rishindra Reddy, Gregory P. Kalemkerian, Bryan J. Schneider, Khaled A. Hassan, Nithya Ramnath, Sunitha Nagrath. High Throughput isolation and expansion of circulating tumor cells (CTCs) from Non-small cell lung cancer (NSCLC) patients for personalized treatments [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1332.

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.

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.

The EGFR T790M Mutation Is Acquired through AICDA-Mediated Deamination of 5-Methylcytosine following TKI Treatment in Lung Cancer

: Almost all patients with EGFR-driven lung cancer who are treated with EGFR tyrosine kinase inhibitors (TKI) develop resistance to treatment. A single base (c.2369C>T) transition mutation, EGFR T790M, is the most frequent resistance event after first-generation exposure to EGFR TKIs. Whether T790M mutation is acquired or is selected from a preexisting clone has been a matter of significant debate. In this study, we show that treatment with EGFR TKIs leads to activation of the NFκB pathway, which in turn induces expression of activation-induced cytidine deaminase (AICDA). In turn, AICDA causes deamination of 5-methylcytosine to thymine at position c.2369 to generate the T790M mutation. Pharmacologic inhibition of the NFκB pathway or knockout of AICDA decreased the frequency or prevented the development of T790M mutation, respectively. In addition, patients treated with first-line EGFR TKI displayed increased expression of AICDA and detection of the T790M mutation upon progression. These results identify the mechanism of T790M acquisition and present an opportunity to target the process to delay or prevent it. SIGNIFICANCE: These findings identify the mechanism behind acquisition of a common resistance mutation to TKI treatment in lung cancer.

Phase II Study of Maintenance Pembrolizumab in Patients with Extensive-Stage Small Cell Lung Cancer (SCLC)

OBJECTIVE

The aim of this study was to assess the efficacy of maintenance pembrolizumab in patients with extensive-stage SCLC after treatment with platinum and etoposide.

METHODS

Patients with extensive-stage SCLC with a response or stable disease after induction chemotherapy were eligible. Pembrolizumab at a dose of 200 mg administered intravenously every 3 weeks was initiated within 8 weeks of the last cycle of chemotherapy. The primary end point of the study was progression-free survival (PFS) from study registration, with overall survival (OS) as a key secondary end point. Available tumor tissue was assessed for expression of programmed death ligand 1 (PD-L1) both in the tumor cells and in the surrounding stroma. Blood for circulating tumor cells was collected before the first, second, and third cycles of pembrolizumab.

RESULTS

Of the 45 patients enrolled, 56% were male and 22% had treated brain metastases. The median PFS was 1.4 months (95% confidence interval [CI]: 1.3-2.8), with a 1-year PFS of 13%. The median OS was 9.6 months (95% CI: 7.0-12), with a 1-year OS of 37%. Of the 30 tumors that could be assessed, three had PD-L1 expression (≥1%) in the tumor cells. A total of 20 tumors could be assessed for PD-L1 expression in the stroma. The median PFS in the eight patients with tumors positive for expression of PD-L1 at the stromal interface was 6.5 months (95% CI: 1.1-12.8) compared with 1.3 months (95% CI: 0.6-2.5) in 12 patients with tumors negative for this marker. No unexpected toxicities were observed.

CONCLUSION

Maintenance pembrolizumab did not appear to improve median PFS compared with the historical data. However, the 1-year PFS rate of 13% and OS rate of 37% suggest that a subset of patients did benefit from pembrolizumab.

Molecular Testing Guideline for the Selection of Patients With Lung Cancer for Treatment With Targeted Tyrosine Kinase Inhibitors: American Society of Clinical Oncology Endorsement of the College of American Pathologists/International Association for the Study of Lung Cancer/Association for Molecular Pathology Clinical Practice Guideline Update

Purpose In response to advances in the field, the College of American Pathologists (CAP), the International Association for the Study of Lung Cancer (IASLC), and the Association for Molecular Pathology (AMP) recently updated their recommendations for molecular testing for the selection of patients with lung cancer for treatment with targeted tyrosine kinase inhibitors. ASCO has a policy and set of procedures for endorsing clinical practice guidelines that have been developed by other professional organizations. Methods The molecular testing guideline was reviewed for developmental rigor by methodologists. Then an ASCO Expert Panel reviewed the content and the recommendations. Results The ASCO Expert Panel determined that the recommendations from the CAP/IASLC/AMP molecular testing guideline are clear, thorough, and based upon the most relevant scientific evidence. ASCO endorsed the guideline with minor modifications. Recommendations This update clarifies that any sample with adequate cellularity and preservation may be tested and that analytical methods must be able to detect mutation in a sample with as little as 20% cancer cells. It strongly recommends against evaluating epidermal growth factor receptor (EGFR) expression by immunohistochemistry for selection of patients for EGFR-targeted therapy. New for 2018 are recommendations for stand-alone ROS1 testing with additional confirmation testing in all patients with advanced lung adenocarcinoma, and RET, ERBB2 (HER2), KRAS, and MET testing as part of larger panels. ASCO also recommends stand-alone BRAF testing in patients with advanced lung adenocarcinoma. Recommendations are also provided for testing methods for lung cancers that have a nonadenocarcinoma non-small-cell component, for patients with targetable mutations who have relapsed on targeted therapy, and for testing the presence of circulating cell-free DNA. Additional information is available at www.asco.org/thoracic-cancer-guidelines and www.asco.org/guidelineswiki .

Prediction of Radiation Esophagitis in Non-Small Cell Lung Cancer Using Clinical Factors, Dosimetric Parameters, and Pretreatment Cytokine Levels

Radiation esophagitis (RE) is a common adverse event associated with radiotherapy for non-small cell lung cancer (NSCLC). While plasma cytokine levels have been correlated with other forms of radiation-induced toxicity, their association with RE has been less well studied. We analyzed data from 126 patients treated on 4 prospective clinical trials. Logistic regression models based on combinations of dosimetric factors [maximum dose to 2 cubic cm (D2cc) and generalized equivalent uniform dose (gEUD)], clinical variables, and pretreatment plasma levels of 30 cytokines were developed. Cross-validated estimates of area under the receiver operating characteristic curve (AUC) and log likelihood were used to assess prediction accuracy. Dose-only models predicted grade 3 RE with AUC values of 0.750 (D2cc) and 0.727 (gEUD). Combining clinical factors with D2cc increased the AUC to 0.779. Incorporating pretreatment cytokine measurements, modeled as direct associations with RE and as potential interactions with the dose-esophagitis association, produced AUC values of 0.758 and 0.773, respectively. D2cc and gEUD correlated with grade 3 RE with odds ratios (ORs) of 1.094/Gy and 1.096/Gy, respectively. Female gender was associated with a higher risk of RE, with ORs of 1.09 and 1.112 in the D2cc and gEUD models, respectively. Older age was associated with decreased risk of RE, with ORs of 0.992/year and 0.991/year in the D2cc and gEUD models, respectively. Combining clinical with dosimetric factors but not pretreatment cytokine levels yielded improved prediction of grade 3 RE compared to prediction by dose alone. Such multifactorial modeling may prove useful in directing radiation treatment planning.

Effect of Midtreatment PET/CT-Adapted Radiation Therapy With Concurrent Chemotherapy in Patients With Locally Advanced Non-Small-Cell Lung Cancer: A Phase 2 Clinical Trial

Importance

Our previous studies demonstrated that tumors significantly decrease in size and metabolic activity after delivery of 45 Gy of fractionated radiatiotherapy (RT), and that metabolic shrinkage is greater than anatomic shrinkage. This study aimed to determine whether 18F-fludeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) acquired during the course of treatment provides an opportunity to deliver higher-dose radiation to the more aggressive areas of the tumor to improve local tumor control without increasing RT-induced lung toxicity (RILT), and possibly improve survival.

Objective

To determine whether adaptive RT can target high-dose radiation to the FDG-avid tumor on midtreatment FDG-PET to improve local tumor control of locally advanced non-small-cell lung cancer (NSCLC).

Design, Setting, and Participants

A phase 2 clinical trial conducted at 2 academic medical centers with 42 patients who had inoperable or unresectable stage II to stage III NSCLC enrolled from November 2008, to May 2012. Patients with poor performance, more than 10% weight loss, poor lung function, and/or oxygen dependence were included, providing that the patients could tolerate the procedures of PET scanning and RT.

Intervention

Conformal RT was individualized to a fixed risk of RILT (grade >2) and adaptively escalated to the residual tumor defined on midtreatment FDG-PET up to a total dose of 86 Gy in 30 daily fractions. Medically fit patients received concurrent weekly carboplatin plus paclitaxel followed by 3 cycles of consolidation.

Main Outcomes and Measures

The primary end point was local tumor control. The trial was designed to achieve a 20% improvement in 2-year control from 34% of our prior clinical trial experience with 63 to 69 Gy in a similar patient population.

Results

The trial reached its accrual goal of 42 patients: median age, 63 years (range, 45-83 years); male, 28 (67%); smoker or former smoker, 39 (93%); stage III, 38 (90%). Median tumor dose delivered was 83 Gy (range, 63-86 Gy) in 30 daily fractions. Median follow-up for surviving patients was 47 months. The 2-year rates of infield and overall local regional tumor controls (ie, including isolated nodal failure) were 82% (95% CI, 62%-92%) and 62% (95% CI, 43%-77%), respectively. Median overall survival was 25 months (95% CI, 12-32 months). The 2-year and 5-year overall survival rates were 52% (95% CI, 36%-66%) and 30% (95% CI, 16%-45%), respectively.

Conclusions and Relevance

Adapting RT-escalated radiation dose to the FDG-avid tumor detected by midtreatment PET provided a favorable local-regional tumor control. The RTOG 1106 trial is an ongoing clinical trial to validate this finding in a randomized fashion.

Trial Registration

clinicaltrials.gov Identifier: NCT01190527.

Radiation-induced lung toxicity in non-small-cell lung cancer: Understanding the interactions of clinical factors and cytokines with the dose-toxicity relationship

BACKGROUND AND PURPOSE

Current methods to estimate risk of radiation-induced lung toxicity (RILT) rely on dosimetric parameters. We aimed to improve prognostication by incorporating clinical and cytokine data, and to investigate how these factors may interact with the effect of mean lung dose (MLD) on RILT.

MATERIALS AND METHODS

Data from 125 patients treated from 2004 to 2013 with definitive radiotherapy for stages I-III NSCLC on four prospective clinical trials were analyzed. Plasma levels of 30 cytokines were measured pretreatment, and at 2 and 4weeks midtreatment. Penalized logistic regression models based on combinations of MLD, clinical factors, and cytokine levels were developed. Cross-validated estimates of log-likelihood and area under the receiver operating characteristic curve (AUC) were used to assess accuracy.

RESULTS

In prognosticating grade 3 or greater RILT by MLD alone, cross-validated log-likelihood and AUC were -28.2 and 0.637, respectively. Incorporating clinical features and baseline cytokine levels increased log-likelihood to -27.6 and AUC to 0.669. Midtreatment cytokine data did not further increase log-likelihood or AUC. Of the 30 cytokines measured, higher levels of 13 decreased the effect of MLD on RILT, corresponding to a lower odds ratio for RILT per Gy MLD, while higher levels of 4 increased the association.

CONCLUSIONS

Although the added prognostic benefit from cytokine data in our model was modest, understanding how clinical and biologic factors interact with the MLD-RILT relationship represents a novel framework for understanding and investigating the multiple factors contributing to radiation-induced toxicity.

Serum MicroRNA Signature Predicts Response to High-Dose Radiation Therapy in Locally Advanced Non-Small Cell Lung Cancer

PURPOSE

To assess the utility of circulating serum microRNAs (c-miRNAs) to predict response to high-dose radiation therapy for locally advanced non-small cell lung cancer (NSCLC).

METHODS AND MATERIALS

Data from 80 patients treated from 2004 to 2013 with definitive standard- or high-dose radiation therapy for stages II-III NSCLC as part of 4 prospective institutional clinical trials were evaluated. Pretreatment serum levels of 62 miRNAs were measured by quantitative reverse transcription-polymerase chain reaction array. We combined miRNA data and clinical factors to generate a dose-response score (DRS) for predicting overall survival (OS) after high-dose versus standard-dose radiation therapy. Elastic net Cox regression was used for variable selection and parameter estimation. Model assessment and tuning parameter selection were performed through full cross-validation. The DRS was also correlated with local progression, distant metastasis, and grade 3 or higher cardiac toxicity using Cox regression, and grade 2 or higher esophageal and pulmonary toxicity using logistic regression.

RESULTS

Eleven predictive miRNAs were combined with clinical factors to generate a DRS for each patient. In patients with low DRS, high-dose radiation therapy was associated with significantly improved OS compared to treatment with standard-dose radiation therapy (hazard ratio 0.22). In these patients, high-dose radiation also conferred lower risk of distant metastasis and local progression, although the latter association was not statistically significant. Patients with high DRS exhibited similar rates of OS regardless of dose (hazard ratio 0.78). The DRS did not correlate with treatment-related toxicity.

CONCLUSIONS

Using c-miRNA signature and clinical factors, we developed a DRS that identified a subset of patients with locally advanced NSCLC who derive an OS benefit from high-dose radiation therapy. This DRS may guide dose escalation in a patient-specific manner.

Phase I Trial of Cediranib in Combination with Cisplatin and Pemetrexed in Chemonaive Patients with Unresectable Malignant Pleural Mesothelioma (SWOG S0905)

INTRODUCTION

In malignant pleural mesothelioma, targeting angiogenesis with cediranib, a vascular endothelial growth factor receptor and platelet-derived growth factor receptor inhibitor, may have therapeutic potential.

METHODS

S0905 phase I combined cediranib (two dose cohorts [30 mg and 20 mg daily]) with cisplatin-pemetrexed for six cycles followed by maintenance cediranib in unresectable chemonaive patients with malignant pleural mesothelioma of any histologic subtype. The primary end point established the maximum tolerated dose in combination with cisplatin-pemetrexed in a dose deescalation scheme.

RESULTS

A total of 20 patients were enrolled (seven to the 30-mg cohort and 13 to the 20-mag cohort). In the cediranib 30-mg cohort, two of the initial six patients reported dose-limiting toxicities and the dose was deemed too toxic to continue. In the next cohort, two patients experienced dose-limiting toxicities, and thus, the maximum tolerated dose of cediranib was established as 20 mg. During the six cycles of cisplatin-pemetrexed-cediranib, 20 mg, there were grade 3 toxicities (neutropenia and gastrointestinal) and grade 4 thrombocytopenia. No patients had any significant episodes of bleeding. According to the Response Evaluation Criteria in Solid Tumors (n = 17 evaluable patients), the median progression-free survival was 12.8 months (95% confidence interval [CI]: 6.9-17.2); according to the Modified Response Evaluation Criteria in Solid Tumors (n = 19 evaluable patients), the median progression-free survival was 8.6 months (95% CI: 6.1-10.9). For all patients, the disease control rate at 6 weeks was 90% and median overall survival time was 16.2 months (95% CI: 10.5-28.7).

CONCLUSIONS

Cediranib combined with cisplatin-pemetrexed has a reasonable toxicity profile and preliminary promising efficacy. The phase II S0905 trial will evaluate the efficacy of the triplet regimen compared with the current standard of care, cisplatin-pemetrexed.

Advances in Small Cell Lung Cancer

Small cell lung cancer (SCLC) is an aggressive neuroendocrine tumor characterized by early metastatic spread and responsiveness to initial therapy. The incidence of SCLC has been declining in the United States in parallel with the decreasing prevalence of cigarette smoking. Limited stage disease is potentially curable with chemoradiotherapy followed by cranial irradiation. Extensive stage disease is incurable, but systemic chemotherapy can improve quality of life and prolong survival. Nearly all patients relapse with chemoresistant disease. Molecularly targeted therapy has failed to yield convincing clinical benefits. Nevertheless, many biologically rational strategies, including immune checkpoint inhibition, show promise in ongoing clinical trials.

Cardiac Events After Radiation Therapy: Combined Analysis of Prospective Multicenter Trials for Locally Advanced Non-Small-Cell Lung Cancer

Purpose Radiation therapy is a critical component in the care of patients with non-small-cell lung cancer (NSCLC), yet cardiac injury after treatment is a significant concern. Therefore, we wished to elucidate the incidence of cardiac events and their relationship to radiation dose to the heart. Patients and Materials Study eligibility criteria included patients with stage II to III NSCLC treated on one of four prospective radiation therapy trials at two centers from 2004 to 2013. All cardiac events were reviewed and graded per Common Terminology Criteria for Adverse Events (v4.03). The primary end point was the development of a grade ≥ 3 cardiac event. Results In all, 125 patients met eligibility criteria; median follow-up was 51 months for surviving patients. Median prescription dose was 70 Gy, 84% received concurrent chemotherapy, and 27% had pre-existing cardiac disease. Nineteen patients had a grade ≥ 3 cardiac event at a median of 11 months (interquartile range, 6 to 24 months), and 24-month cumulative incidence was 11% (95% CI, 5% to 16%). On multivariable analysis (MVA), pre-existing cardiac disease (hazard ratio [HR], 2.96; 95% CI, 1.07 to 8.21; P = .04) and mean heart dose (HR, 1.07/Gy; 95% CI, 1.02 to 1.13/Gy; P = .01) were significantly associated with grade ≥ 3 cardiac events. Analyzed as time-dependent variables on MVA analysis, both disease progression (HR, 2.15; 95% CI, 1.54 to 3.00) and grade ≥ 3 cardiac events (HR, 1.76; 95% CI, 1.04 to 2.99) were associated with decreased overall survival. However, disease progression (n = 71) was more common than grade ≥ 3 cardiac events (n = 19). Conclusion The 24-month cumulative incidence of grade ≥ 3 cardiac events exceeded 10% among patients with locally advanced NSCLC treated with definitive radiation. Pre-existing cardiac disease and higher mean heart dose were significantly associated with higher cardiac event rates. Caution should be used with cardiac dose to minimize risk of radiation-associated injury. However, cardiac risks should be balanced against tumor control, given the unfavorable prognosis associated with disease progression.

Lower Incidence of Esophagitis in the Elderly Undergoing Definitive Radiation Therapy for Lung Cancer

INTRODUCTION

Most patients with lung cancer are elderly and poorly represented in randomized clinical trials. They are often undertreated because of concerns about their ability to tolerate aggressive treatment. We tested the hypothesis that elderly patients undergoing definitive lung radiation might tolerate treatment differently than younger patients.

METHODS

A total of 125 patients who underwent definitive lung radiotherapy were identified from a prospective institutional database (University of Michigan cohort). Logistic regression modeling was performed to assess the impact of age on esophagitis grade 2 or higher or grade 2 or higher and pneumonitis grade 3 or higher or grade 2 or higher, with adjustment for esophageal and lung dose, respectively, as well as for chemotherapy utilization, smoking status, and performance status. The analysis was validated in a large cohort of 691 patients from the Michigan Radiation Oncology Quality Consortium registry, an independent statewide prospective database.

RESULTS

In the University of Michigan cohort, multivariable regression models revealed a significant inverse correlation between age and rate of esophagitis for both toxicity levels, (adjusted OR = 0.93 for both models and 95% confidence intervals of 0.88-0.98 and 0.87-0.99), with areas under the curve of 0.747 and 0.721, respectively, demonstrating good fit. This same association was noted in the Michigan Radiation Oncology Quality Consortium cohort. There was no significant association between age and pneumonitis.

CONCLUSIONS

There is a lower incidence of esophagitis with increasing age even after adjustment for use of chemotherapy. This is a novel finding in thoracic oncology. No age dependence was noted for pulmonary toxicity. The elderly are able to tolerate definitive thoracic radiation well and should be offered this option when clinically warranted.

Phase II Trial of Dose-dense Pemetrexed, Gemcitabine, and Bevacizumab in Patients With Advanced, Non-Small-cell Lung Cancer

INTRODUCTION

Platinum-based chemotherapy is standard for untreated, advanced non-small-cell lung cancer (NSCLC). We investigated the activity and tolerability of the novel combination of dose-dense pemetrexed, gemcitabine, and bevacizumab in patients with advanced NSCLC.

METHODS

This multicenter phase II trial evaluated the safety and efficacy of the combination of pemetrexed (400 mg/m²), gemcitabine (1200 mg/m²), and bevacizumab (10 mg/kg), given every 14 days in patients with untreated, advanced NSCLC. The primary endpoint was progression-free survival with secondary endpoints of response rate and overall survival.

RESULTS

Thirty-nine patients were enrolled. Treatment was well tolerated; the most common grade 3-4 toxicities were neutropenia and fatigue. Of the 38 patients evaluable for tumor response, 1 (3%) had complete response, 15 (39%) had partial response, 12 (31%) had stable disease, and 10 (26%) had progressive disease. Median progression-free survival was 6.1 months (95% confidence interval [CI], 4.2-7.9) and median overall survival was 18.4 months (95% CI, 13.1-29.5). The 1-year overall survival rate was 64% (95% CI, 51%-81%) and the 2-year overall survival rate was 41% (95% CI, 28%-60%).

CONCLUSIONS

Treatment with dose-dense pemetrexed, gemcitabine, and bevacizumab met the primary endpoint with promising efficacy and a manageable safety profile in patients with untreated advanced NSCLC. This regimen represents a reasonable therapeutic option.

Small Cell Lung Cancer

Small cell lung cancer (SCLC) is a high-grade neuroendocrine tumor characterized by rapid growth, early metastatic spread, and initial responsiveness to therapy. Although the incidence of SCLC is declining, it remains one of the common causes of cancer-related mortality. Initial evaluation of patients with SCLC should focus on determining the extent of disease and the ability of the patient to tolerate specific therapy. Positron emission tomography (PET) can improve the accuracy of staging and treatment planning in many patients. Limited-stage (LS) SCLC is a potentially curable disease with long-term survival of 20 to 25% when treated with platinum-based chemotherapy plus concurrent thoracic radiation. Hyperfractionated (twice daily) thoracic radiation and prophylactic cranial irradiation (PCI) may improve survival in selected patients with LS-SCLC. For patients with extensive-stage (ES) SCLC, combination chemotherapy prolongs survival and improves quality of life, but long-term survival is rare. The use of PCI and sequential thoracic radiation has been reported to improve survival in selected patients with ES-SCLC. Many chemotherapeutic drugs have activity in SCLC, but little progress has been made in the systemic treatment of SCLC in almost three decades. Although many potential molecular targets have been identified in the preclinical studies of SCLC, molecularly targeted therapy has yet to demonstrate consistent clinical activity. Nevertheless, future advances in SCLC will depend on the development of rational therapeutic strategies which target the molecular mechanisms that drive cellular proliferation, survival, and immunological avoidance.

Personalized Therapy of Small Cell Lung Cancer

Small cell lung cancer (SCLC) is an aggressive, poorly differentiated neuroendocrine carcinoma with distinct clinical, pathological and molecular characteristics. Despite robust responses to initial chemotherapy and radiation, the prognosis of patients with SCLC remains poor with an overall 5-year survival rate of less than 10 %. Despite the fact that numerous molecularly targeted approaches have thus far failed to demonstrate clinical utility in SCLC, further advances will rely on better definition of the biological pathways that drive survival, proliferation and metastasis. Recent next-generation, molecular profiling studies have identified many new therapeutic targets in SCLC, as well as extreme genomic instability which explains the high degree of resistance. A wide variety of anti-angiogenic agents, growth factor inhibitors, pro-apoptotic agents, and epigenetic modulators have been evaluated in SCLC and many studies of these strategies are on-going. Perhaps the most promising approaches involve agents targeting cancer stem cell pathways and immunomodulatory drugs that interfere with the PD1 and CTLA-4 pathways. SCLC offers many barriers to the development of successful therapy, including limited tumor samples, inadequate preclinical models, high mutational burden, and aggressive tumor growth which impairs functional status and hampers enrollment on clinical trials.

A statistical evaluation of dose expansion cohorts in phase I clinical trials

BACKGROUND

Phase I trials often include a dose expansion cohort (DEC), in which additional patients are treated at the estimated maximum tolerated dose (MTD) after dose escalation, with the goal of ensuring that data are available from more than six patients at a single dose level. However, protocols do not always detail how, or even if, the additional toxicity data will be used to reanalyze the MTD or whether observed toxicity in the DEC will warrant changing the assigned dose. A DEC strategy has not been statistically justified.

METHODS

We conducted a simulation study of two phase I designs: the "3+3" and the Continual Reassessment Method (CRM). We quantified how many patients are assigned the true MTD using a 10 to 20 patient DEC and how a sensible reanalysis using the DEC changes the probability of selecting the true MTD. We compared these results with those from an equivalently sized larger CRM that does not include a DEC.

RESULTS

With either the 3+3 or CRM, reanalysis with the DEC increased the probability of identifying the true MTD. However, a large CRM without a DEC was more likely to identify the true MTD while still treating 10 or 15 patients at this dose level.

CONCLUSIONS

Where feasible, a CRM design with no explicit DEC is preferred to designs that fix a dose for all patients in a DEC.

Advances in pharmacotherapy of small cell lung cancer

INTRODUCTION

Small cell lung cancer (SCLC) is an aggressive malignancy characterized by early metastatic dissemination and responsiveness to initial therapy. The incidence of SCLC has been declining over the past two decades. Limited-stage SCLC is a potentially curable disease with long-term survival of ∼ 20% when treated with platinum-based chemotherapy plus concurrent thoracic radiation and prophylactic cranial irradiation. For patients with extensive-stage SCLC, survival can be increased with combination platinum-based chemotherapy, but the disease remains incurable.

AREAS COVERED

This review looks at the current advances in pharmacotherapy for SCLC.

EXPERT OPINION

Many chemotherapeutic strategies and newer cytotoxic agents have been evaluated in SCLC, and some had promising activity in early clinical trials. However, none have demonstrated consistent improvements in outcome over standard platinum-based treatment. Similarly, although many potential molecular targets have been identified in preclinical studies of SCLC, molecularly targeted therapy has yet to demonstrate any substantial activity in clinical trials. Nonetheless, future advances in this disease will undoubtedly depend on improvements in our understanding of the molecular mechanisms that drive the proliferation and survival of SCLC cells.