Phase III trial comparing supportive care alone with supportive care with oral topotecan in patients with relapsed small-cell lung cancer

NGR-hTNF and Doxorubicin as Second-Line Treatment of Patients with Small Cell Lung Cancer

Lessons Learned.

NGR‐hTNF was safely combined with doxorubicin, showing a promising antitumor activity in unselected patients with relapsed small cell lung cancer.

Similar antitumor activity was observed in platinum‐sensitive and platinum‐resistant patient cohorts.

Background.

Relapsed small cell lung cancer (SCLC) patients have limited treatment options and poor outcomes. NGR‐hTNF is a vascular‐targeting agent, which increases intratumoral chemotherapy penetration and T‐lymphocyte infiltration.

Methods.

Twenty‐eight patients relapsing after at least one platinum‐based regimen with a treatment‐free interval shorter (n = 16; platinum‐resistant) or longer (n = 12; platinum‐sensitive) than 3 months received NGR‐hTNF 0.8 μg/m² plus doxorubicin 75 mg/m² every 3 weeks. The primary endpoint of this single‐arm phase II trial was progression‐free survival (PFS), and safety, response rate, and survival were secondary endpoints.

Results.

The most common grade 3–4 toxicities were neutropenia (53%) and anemia (21%). Median PFS was 3.2 months for all patients, 2.7 months for platinum‐resistant patients, and 4.1 months for platinum‐sensitive patients. Seven patients had partial responses (25%), including four (25%) with platinum‐resistant and three (25%) with platinum‐sensitive relapse. Mean changes from baseline in tumor burden (after two, four, and six cycles) did not differ between platinum‐resistant (−9%, −29%, and −32%) and platinum‐sensitive (−11%, −20%, and −43%) cohorts. Overall survival was associated only with baseline lymphocyte counts, with median survival times of 13.1 and 5.2 months for lymphocyte counts above or below the median, respectively.

Conclusion.

NGR‐hTNF plus doxorubicin showed manageable toxicity and promising activity in patients with relapsed SCLC.

Randomized, Double-Blind, Phase II Study of Temozolomide in Combination With Either Veliparib or Placebo in Patients With Relapsed-Sensitive or Refractory Small-Cell Lung Cancer

Purpose Both temozolomide (TMZ) and poly (ADP-ribose) polymerase (PARP) inhibitors are active in small-cell lung cancer (SCLC). This phase II, randomized, double-blind study evaluated whether addition of the PARP inhibitor veliparib to TMZ improves 4-month progression-free survival (PFS). Patients and Methods A total of 104 patients with recurrent SCLC were randomly assigned 1:1 to oral veliparib or placebo 40 mg twice daily, days 1 to 7, and oral TMZ 150 to 200 mg/m²/day, days 1 to 5, of a 28-day cycle until disease progression, unacceptable toxicity, or withdrawal of consent. Response was determined by imaging at weeks 4 and 8, and every 8 weeks thereafter. Improvement in PFS at 4 months was the primary end point. Secondary objectives included overall response rate (ORR), overall survival (OS), and safety and tolerability of veliparib with TMZ. Exploratory objectives included PARP-1 and SLFN11 immunohistochemical expression, MGMT promoter methylation, and circulating tumor cell quantification. Results No significant difference in 4-month PFS was noted between TMZ/veliparib (36%) and TMZ/placebo (27%; P = .19); median OS was also not improved significantly with TMZ/veliparib (8.2 months; 95% CI, 6.4 to 12.2 months; v 7.0 months; 95% CI, 5.3 to 9.5 months; P = .50). However, ORR was significantly higher in patients receiving TMZ/veliparib compared with TMZ/placebo (39% v 14%; P = .016). Grade 3/4 thrombocytopenia and neutropenia more commonly occurred with TMZ/veliparib: 50% versus 9% and 31% versus 7%, respectively. Significantly prolonged PFS (5.7 v 3.6 months; P = .009) and OS (12.2 v 7.5 months; P = .014) were observed in patients with SLFN11-positive tumors treated with TMZ/veliparib. Conclusion Four-month PFS and median OS did not differ between the two arms, whereas a significant improvement in ORR was observed with TMZ/veliparib. SLFN11 expression was associated with improved PFS and OS in patients receiving TMZ/veliparib, suggesting a promising biomarker of PARP-inhibitor sensitivity in SCLC.

Managing Patients With Relapsed Small-Cell Lung Cancer

Despite high response rates to initial therapy, relapses are common in patients with small-cell lung cancer (SCLC). Systemic therapy after first-line failure remains important in the treatment paradigm of SCLC. Reinitiation of a previously administered first-line chemotherapy regimen is recommended for relapse > 6 months from completion of initial therapy. For relapse ≤ 6 months of initial therapy, sequential therapy with single agents is recommended. Clinical trial enrollment should be considered at all stages of treatment of SCLC. This review highlights the available treatment options in relapsed SCLC. In particular, we focus on prospective clinical trials demonstrating activity for the most commonly used agents in this setting. We end with a discussion on future directions and emerging targets with potential to improve outcomes in relapsed SCLC.

Immunohistochemical expression and prognostic value of PD-L1 in Extrapulmonary small cell carcinoma: a single institution experience

BACKGROUND

Extrapulmonary small cell carcinomas (ESCC) are rare but aggressive tumors. Relapses are common despite treatment with chemotherapy and/or radiotherapy. Prospective data for treatment of ESCC are lacking; treatment of these cancers usually incorporates lung small cell carcinoma treatment recommendations. Cancer staging remains the most important prognostic factor. Cancer immunotherapy targeting the PD-1/PD-L1 pathway has shown efficacy in multiple tumor types, and could be an appealing treatment strategy for these rare tumors.

METHODS

We investigated PD-L1 expression by immunochemistry (IHC) in ESCCs diagnosed at University of Massachusetts Medical Center, from 1999 to 2016. 34 cases with sufficient material were selected for PD-L1 IHC analysis using clone E1L3N. PD-L1 expression was evaluated using the combined positive score (CPS). Retrospective chart review was performed. We evaluated the incidence and prognostic value of PD-L1 expression in ESCC at our institution.

RESULTS

Twelve out 34 cases (35%) had PD-L1 CPS scores ≥1. Ten cases had CPS scores ranging 1-5, whereas 2 cases had CPS scores > 80. The overall response rate to the standard chemotherapy with/without radiotherapy in the PD-L1 positive group was 80% versus 67% for the PDL-1 negative group (p-value 0.67). The median overall survival for the PD-L1 positive group, regardless of stage, was 11.5 months versus 7 months for PD-L1 negative group (p-value 0.34). Patients with limited stage disease with positive PD-L1 had a median survival of 53 months compared to 15 months for patients with PD-L1 negative limited stage (p-value 0.80).

CONCLUSIONS

This study showed that at least one third of our ESCC tissue samples expressed PD-L1. There was a trend for higher response rates to the standard chemotherapy with/without radiotherapy and improved survival in PD-L1 positive patients. Further studies are required to understand the implications of immune dysregulation in these aggressive tumors. PD-L1/PD-1 inhibitors should be investigated in this group of patients.

Modeling small cell lung cancer (SCLC) biology through deterministic and stochastic mathematical models

Mathematical cancer models are immensely powerful tools that are based in part on the fractal nature of biological structures, such as the geometry of the lung. Cancers of the lung provide an opportune model to develop and apply algorithms that capture changes and disease phenotypes. We reviewed mathematical models that have been developed for biological sciences and applied them in the context of small cell lung cancer (SCLC) growth, mutational heterogeneity, and mechanisms of metastasis. The ultimate goal is to develop the stochastic and deterministic nature of this disease, to link this comprehensive set of tools back to its fractalness and to provide a platform for accurate biomarker development. These techniques may be particularly useful in the context of drug development research, such as combination with existing omics approaches. The integration of these tools will be important to further understand the biology of SCLC and ultimately develop novel therapeutics.

Advanced small cell lung cancer (SCLC): new challenges and new expectations

Small cell lung cancer (SCLC) remains one of the most lethal malignancies and a major health riddle. The therapeutic options are limited. The combination of etoposide or irinotecan with platinum chemotherapy is the standard of care at any stage. The last decade systemic efforts have been done to reveal specific therapeutic targets for small cell lung carcinomas. In this review, we focus on the new therapeutic strategies of SCLC, including immune-related treatment that may change the prognosis of the disease. The main genetic mutations observed in SCLC are TP53 and RB1 mutations; however, it is well known that these molecules are not yet targetable. In recent years, research has revealed other frequent genetic alterations and activated signaling pathways that might be an effective treatment target. Loss of PTEN, activating PI3K mutations, inhibition of NOTCH pathway and aurora kinase activation are among them. Moreover, FDGFR1 amplification, activation of the Hedgehog pathway and repair-protein PARP1 seem to participate in SCLC tumorigenesis. These new findings have identified some interesting targets. Moreover, immunotherapy tries to find its place in the treatment of SCLC. Immune checkpoint inhibitors are under investigation in phase I to III clinical trials. We hope that in next years the treatment of SCLC patients will be improved with the administration of targeting therapy and the introduction of immunotherapy.

Current and future therapeutic approaches for the treatment of small cell lung cancer

INTRODUCTION

Small-cell lung cancer (SCLC) is a very aggressive disease characterized by a high response rate to first-line chemotherapy, but most patients relapse within 1 year with disappointing results to second-line treatments. Chemotherapy has reached a plateau of effectiveness and new therapeutic strategies are needed to change the natural history of SCLC. Areas covered: This review will focus on the current results and the future development of the therapeutic approaches for the treatment of SCLC. Expert commentary: Immunotherapy is becoming a new frontier for the management of SCLC with preliminary interesting results. To date, no targeted drugs have been approved for clinical practice but several novel agents are in an advanced stage of clinical development in SCLC.

A Phase Ib/II Study of Ganetespib With Doxorubicin in Advanced Solid Tumors Including Relapsed-Refractory Small Cell Lung Cancer

Introduction

Small cell lung cancer (SCLC) accounts for 15% of all lung cancers and is characterized by high response rates to cytotoxic chemotherapy and equally high rates of relapse. Many resistance mechanisms have been proposed including resistance to doxorubicin via induction of a heat shock response. Ganetespib is a novel and potent non-geldanamycin heat shock protein 90 (Hsp90) inhibitor. In preclinical studies, synergy between ganetespib and doxorubicin was shown. We conducted a phase Ib/II study of the safety, tolerability, and preliminary efficacy of the combination of ganetespib and doxorubicin.

Methods

Patients eligible for the phase Ib portion had advanced tumors that would be appropriate for doxorubicin therapy and those in the phase II portion had relapsed or refractory SCLC. All patients had an ECOG performance status, 0–1 and adequate organ function, including a cardiac ejection fraction ≥50%. Patients who received a lifetime cumulative doxorubicin dose of >150 mg/m² or who had symptomatic brain metastases were excluded. Patients received ganetespib on Days 1 and 8 and doxorubicin 50 mg/m² on day 1 in 21-day cycles.

Results

Eleven patients were enrolled including nine in the phase Ib dose escalation and two in the phase II expansion. The study was terminated by the sponsor. The dose recommended for future study is ganetespib 150 mg/m² in combination with doxorubicin at a dose of 50 mg/m². The most common adverse events of the combination were grade 1/2 diarrhea, nausea, fatigue, and transaminitis. No dose limiting toxicities were observed. Response rate was 25% and median duration of response was 137 days.

Conclusion

Ganetespib plus doxorubicin was a well-tolerated combination and there remains potential for the clinical development of Hsp90 inhibitors in SCLC.

Clinical Trial Registration

https://ClinicalTrials.gov/ct2/show/NCT02261805, identifier NCT02261805.

The effect of post-progression survival on overall survival among patients with sensitive relapse of small cell lung cancer

Recent studies have suggested that, among patients with advanced lung cancer, subsequent treatment after failure of first-line or second-line chemotherapy has a greater effect on overall survival (OS) than tumor shrinkage or progression-free survival (PFS). However, no studies have examined this issue among patients with sensitive relapse of small cell lung cancer (SCLC). We retrospectively evaluate 77 patients with sensitive relapse of SCLC who received second-line chemotherapy after first-line platinum doublet chemotherapy between January 1999 and November 2013. The analyses included patient characteristics, treatment parameters, tumor shrinkage, PFS, post-progression survival (PPS), and OS. Spearman rank correlation analysis and linear regression analysis revealed that PPS was strongly correlated with OS (r = 0.91, p < 0.01, R² = 0.96), PFS was moderately correlated with OS (r = 0.58, p < 0.01, R² = 0.28), and tumor shrinkage was weakly correlated with OS (r = 0.34, p < 0.01, R² = 0.12). A multivariate Cox proportional hazards model with a stepwise regression procedure revealed that PPS was significantly associated with age at the start of second-line chemotherapy, best response to second-line and third-line chemotherapy, and the number of regimens after progression beyond second-line chemotherapy (p < 0.05). These findings suggest that PPS has a stronger effect than PFS on OS among patients with sensitive relapse of SCLC. Thus, response to second-line chemotherapy and subsequent treatment for disease progression after second-line chemotherapy may be important factors that influence OS.

Current standards for clinical management of small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive high-grade neuroendocrine carcinoma. Despite over 30 years of clinical research, little progress has been made in the management of SCLC, and outcomes remain poor. Here, we review the current clinical standards for management of SCLC and the data supporting these strategies.

A phase II trial of Ifosfamide combination with recommended supportive therapy for recurrent SCLC in second-line and heavily treated setting

PURPOSE

The response rate of ifosfamide (IFM) monotherapy for small-cell lung cancer (SCLC) is reported as 42.4% in Japanese package insert. However, these efficacy data are based on clinical studies conducted in 1970s. This phase II study evaluated the efficacy and safety of IFM combination with recommended current supportive therapy for recurrent SCLC in second-line and heavily treated setting.

METHODS

Recurrent SCLC patients pretreated with one to three prior regimens received IFM monotherapy (1.5 g/m² for 3 days every 3 weeks). Treatment was continued until disease progression or unacceptable toxicity. The primary end point was objective response rate.

RESULTS

Twelve patients were enrolled in the study from June 2009 to January 2013. The study was early terminated at interim analysis due to futility stop. Patient characteristics were as follows: median age was 65 years, 11 were males (91.7%) and eight (66.7%) and four (33.3%) were Performance Status 0 and 1, respectively. Four patients (33.3%) enrolled in second-line setting were all refractory relapse SCLC and 8 (66.7%) were heavily treated patients. No patient showed objective response. Stable disease was observed in 3 patients. Median progression-free survival and overall survival were 0.9 months (95% CI, 0.3-1.5) and 4.8 months (95% CI, 1.6-9.9), respectively. Although one grade 4 amylase increase possibly related to IFM was observed, toxicity profile was totally favorable.

CONCLUSIONS

IFM monotherapy should not be used for refractory relapse or heavily treated SCLC, and no further investigation is required in these populations.

Current Treatments for Surgically Resectable, Limited-Stage, and Extensive-Stage Small Cell Lung Cancer

The prevalence of small cell lung cancer (SCLC) has declined in the U.S. as the prevalence of tobacco use has declined. However, a significant number of people in the U.S. are current or former smokers and are at risk of developing SCLC. Routine histological or cytological evaluation can reliably make the diagnosis of SCLC, and immunohistochemistry stains (thyroid transcription factor-1, chromogranin, synaptophysin, and CD56) can be used if there is uncertainty about the diagnosis. Rarely do patients present with SCLC amendable to surgical resection, and evaluation requires a meticulous workup for extra-thoracic metastases and invasive staging of the mediastinum. Resected patients require adjuvant chemotherapy and/or thoracic radiation therapy (TRT), and prophylactic cranial radiation (PCI) should be considered depending on the stage. For limited-stage disease, concurrent platinum-etoposide and TRT followed by PCI is the standard. Thoracic radiation therapy should be started early in treatment, and can be given twice daily to 45 Gy or once daily to 60-70 Gy. For extensive-stage disease, platinum-etoposide remains the standard first-line therapy, and the standard second-line therapy is topotecan. Preliminary studies have demonstrated the activity of immunotherapy, and the response rate is approximately 10-30% with some durable responses observed. Rovalpituzumab tesirine, an antibody drug conjugate, has shown promising activity in patients with high delta-like protein 3 tumor expression (approximately 70% of patients with SCLC). The emergence of these and other promising agents has rekindled interest in drug development in SCLC. Several ongoing trials are investigating novel agents in the first-line, maintenance, and second-line settings.

IMPLICATIONS FOR PRACTICE

This review will provide an update on the standard therapies for surgically resected limited-stage small cell lung cancer and extensive-stage small cell lung cancer that have been investigated in recent clinical trials.

High expression of topoisomerase-II predicts favorable clinical outcomes in patients with relapsed small cell lung cancers receiving amrubicin

OBJECTIVES

Amrubicin monotherapy is a treatment option for patients with relapsed small cell lung cancers (SCLCs). Topoisomerase-II (Topo-II) - a target of amrubicin - has been reported as a predictive or prognostic marker for chemosensitivity or outcomes in patients with various malignancies. Here, we investigated the prognostic role of Topo-II expression in patients with relapsed SCLCs who underwent amrubicin monotherapy.

MATERIALS AND METHODS

Eighty-three patients with relapsed SCLCs who received amrubicin monotherapy between 2004 and 2015, after progression beyond first-line chemotherapy, were enrolled in the study. We retrospectively collected clinical data from their medical records, and evaluated the expression levels of Topo-II, by immunohistochemical staining of archival tumor specimens obtained through surgical resections or biopsies.

RESULTS

Most of the enrolled patients were elderly men (89%), with a median age of 70 years (range, 49-83); 16% of these patients showed Topo-II overexpression. Compared to patients with sensitive relapses, those with refractory relapses showed significantly higher Topo-II expression levels (P=0.03). The overall response rates in patients with high and low Topo-II expression were 38.5% and 25.7%, respectively (P=0.34). Multivariate analysis confirmed that patients with a higher Topo-II expression level had significantly longer progression-free survival (hazard ratio (HR), 0.39; P<0.01) and overall survival (HR, 0.48; P=0.04), compared to patients with a lower Topo-II expression level.

CONCLUSION

Our study identified Topo-II expression as a significant biomarker for the prediction of favorable outcomes in patients with relapsed SCLCs who underwent treatment with amrubicin, a Topo-II inhibitor. Thus, Topo-II expression may be a promising predictor of the efficacy of amrubicin.

Receipt of thoracic radiation therapy and radiotherapy dose are correlated with outcomes in a retrospective study of three hundred and six patients with extensive stage small-cell lung cancer

BACKGROUND

The importance of the thoracic radiation therapy (TRT) dose has not been clearly defined in extensive stage small-cell lung cancer (ES-SCLC) and it is unclear whether improved TRT dose translates into a survival benefit.

METHODS

306 patients with ES-SCLC were retrospectively reviewed, of which 170 received IMRT/CRT fractionation RT after ChT, and 136 received chemotherapy (ChT) alone. We adopted the time-adjusted BED (tBED) for effective dose fractionation calculation. Due to the nonrandomized nature of this study, we compared the ChT+RT with ChT groups that matched on possible confounding variables.

RESULTS

Patients achieved 2-year OS, PFS and LC rates of 19.7%, 10.7% and 28.4%, respectively. After propensity score matching, (113 cases for each group), the rates of OS, PFS and LC at 2 years were 21.4%, 7.7% and 34.5% for ChT+TRT, and 10.3% (p<0.001), 4.6% (p<0.001) and 6.3% for ChT only (p<0.001), respectively. Among propensity score matching patients, 56 cases for each group received the high dose (tBED>50 Gy) TRT and received low dose (tBED≤50 Gy) TRT. Two-year OS, PFS and LC rates were 32.3%, 15.3% and 47.1% for the high dose compared with 17.0% (p<0.001), 12.9% (p=0.097) and 34.7% (p=0.029) for low dose radiotherapy.

CONCLUSIONS

TRT added to ChT improved ES-SCLC patient OS. High dose TRT improved OS over lower doses. Our results suggest that high-dose thoracic radiation therapy may be a reasonable consideration in select patients with ES-SCLC.

Paclitaxel as third-line chemotherapy for small cell lung cancer failing both etoposide- and camptothecin-based chemotherapy

Paclitaxel has been shown to have clinical activity in the treatment of small cell lung cancer (SCLC). However, its role as third-line chemotherapy for SCLC after both etoposide- and camptothecin-based regimens has not been clarified.All patients with refractory SCLC who were treated with paclitaxel-based regimen as third-line chemotherapy between 2005 and 2011 in Seoul National University Bundang Hospital were reviewed retrospectively. Forty patients previously treated with both etoposide- and camptothecin-based chemotherapy were included.The median age of the enrolled patients was 67 years (range, 35-86 years). Most patients (77.5%) received cisplatin plus etoposide as first-line therapy, and camptothecins such as irinotecan or topotecan as second-line therapy. Of 34 patients with measurable lesions, 8 patients (23.5%) achieved partial response and 9 (26.5%) had stable disease. The median progression-free survival (PFS) and overall survival (OS) were 2.5 and 5.9 months, respectively. Predictive factors for OS were performance status (PS) (PS <2 vs ≥2; P = .001), the presence of liver metastasis (P < .001), and number of metastatic sites (<3 vs ≥3; P = .047) in univariate analysis. PS and liver metastasis also remained statistically significant in multivariate analysis. Grade 3 or 4 hematologic toxicity was 20% for neutropenia, and 10% for thrombocytopenia. Other common non-hematological toxicities were peripheral neuropathy and mild liver enzyme elevation.Paclitaxel-based chemotherapy showed modest activity in SCLC patients refractory to both etoposide- and camptothecin-based chemotherapy. PS and presence of liver metastasis were predictive of survival after paclitaxel chemotherapy.

[Clinical Development of Immune Checkpoint Inhibitors in Patients with Small Cell Lung Cancer]

Small cell lung cancer (SCLC) is a poorly differentiated high-grade neuroendocrine tumor, accounts for approximately 14% of all lung cancers. SCLC is characterized by rapid growth, early metastasis without effective treatments after recurrence. It is urgently need to improve the therapy of patients with SCLC. In recent years Tumor immunotherapy has shown promising efficacy, especially in immune checkpoints including inhibitors programmed cell-death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). These immune checkpoint inhibitors of the researches are changing the clinical practice of many kinds of solid tumor. SCLC is a potential ideal type of tumor immunotherapy for tobacco exposure and the highest mutational load. In this report, the authors review the current state of the immunotherapy in SCLC, to discussing the problems, challenge and application development prospect.

Efficacy of nanoparticle albumin-bound paclitaxel regimens for relapsed small cell lung cancer: A retrospective analysis

Although small cell lung cancer (SCLC) is initially sensitive to chemotherapy, it recurs in most cases. Standard regimens for salvage chemotherapy have not been established, and the prognosis of relapsed SCLC remains poor. In the present study, we investigated the clinical efficacy and safety of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) regimens for the treatment of relapsed SCLC.In this retrospective multicenter analysis, 14 patients (3 women and 11 men; median age 71 years) with relapsed SCLC received nab-paclitaxel alone or in combination with carboplatin between February 2013 and July 2014. The safety and efficacy of the regimens were evaluated.The response rates, disease control rates, and median overall survival for the total patient population were 36%, 64%, and 7.8 months, respectively. Response rates, disease control rates, and the median overall survival were 11%, 44%, and 4 months, respectively, in the monotherapy group; and 80%, 100%, and 10.6 months, respectively, in the combination therapy group. The most common adverse events were hematological toxicities such as neutropenia and anemia. Severe neutropenia appeared in some patients, although it was resolved by treatment in all. The most common nonhematological toxicity was anorexia (64%), followed by neurotoxicity and constipation. All nonhematological toxicities were mild and manageable.Our results suggest that chemotherapy with nab-paclitaxel regimens for relapsed SCLC exhibits moderate clinical efficacy and is well-tolerated. Further clinical trials in relapsed SCLC patients are warranted.

Checkpoint Blockade in Lung Cancer and Mesothelioma

In the last decade, immunotherapy has emerged as a new treatment modality in cancer. The most success has been achieved with the class of checkpoint inhibitors (CPIs), antibodies that unleash the antitumor immune response. After the success in melanoma, numerous clinical trials are being conducted investigating CPIs in lung cancer and mesothelioma. The programmed death protein (PD) 1-PD ligand 1/2 pathway and cytotoxic T lymphocyte-associated protein 4 are currently the most studied immunotherapeutic targets in these malignancies. In non-small cell lung cancer, anti-PD-1 antibodies have become part of the approved treatment arsenal. In small cell lung cancer and mesothelioma, the efficacy of checkpoint inhibition has not yet been proven. In this Concise Clinical Review, an overview of the landmark clinical trials investigating checkpoint blockade in lung cancer and mesothelioma is provided. Because response rates are around 20% in the majority of clinical trials, there is much room for improvement. Predictive biomarkers are therefore essential to fully develop the potential of CPIs. To increase efficacy, multiple clinical trials investigating the combination of cytotoxic T lymphocyte-associated protein 4 inhibitors and PD-1/PD ligand 1 blockade in lung cancer and mesothelioma are being conducted. Given the potential benefit of immunotherapy, implementation of current and new knowledge in trial designs and interpretation of results is essential for moving forward.

Circulating tumor cell interactions with macrophages: implications for biology and treatment

Cancer and metastasis are closely associated with inflammation. Macrophages are important effector cells in enhancing tumor proliferation, invasion and providing protection against the immune system. Despite advanced knowledge of tumor-macrophage interactions, the role of macrophages in emergence and invasion of circulating tumor cells (CTCs) is not known. A series of six CTC cell lines have been derived from blood of patients with extensive disease small cell lung cancer (ED-SCLC) in our lab, most likely representing a homogenous cell population of the actual metastasis-initiating cells (MIC) of CTCs. SCLC has an unfavorable prognosis due to rapid dissemination and early chemoresistant relapses. SCLC CTCs recruit macrophages and elicit secretion of various cytokines and the six CTC lines express chitinase-3-like-1 (CHI3L1), vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP9) in abundance. CHI3L1 is cytokine/growth factor expressed in inflammation and cancer and found to be correlated to metastasis and a dismal prognosis. In conclusion, SCLC CTCs have acquired the essential means for aggressiveness and invasion in a tumor microenvironment specifically shaped by macrophages and inflammation.

Targeting AXL and mTOR Pathway Overcomes Primary and Acquired Resistance to WEE1 Inhibition in Small-Cell Lung Cancer

Purpose: Drugs targeting DNA repair and cell-cycle checkpoints have emerged as promising therapies for small-cell lung cancer (SCLC). Among these, the WEE1 inhibitor AZD1775 has shown clinical activity in a subset of SCLC patients, but resistance is common. Understanding primary and acquired resistance mechanisms will be critical for developing effective WEE1 inhibitor combinations.Experimental Design: AZD1775 sensitivity in SCLC cell lines was correlated with baseline expression level of 200 total or phosphorylated proteins measured by reverse-phase protein array (RPPA) to identify predictive markers of primary resistance. We further established AZD1775 acquired resistance models to identify mechanism of acquired resistance. Combination regimens were tested to overcome primary and acquired resistance to AZD1775 in in vitro and in vivo SCLC models.Results: High-throughput proteomic profiling demonstrate that SCLC models with primary resistance to AZD1775 express high levels of AXL and phosphorylated S6 and that WEE1/AXL or WEE1/mTOR inhibitor combinations overcome resistance in vitro and in vivo Furthermore, AXL, independently and via mTOR, activates the ERK pathway, leading to recruitment and activation of another G2-checkpoint protein, CHK1. AZD1775 acquired resistance models demonstrated upregulation of AXL, pS6, and MET, and resistance was overcome with the addition of AXL (TP0903), dual-AXL/MET (cabozantinib), or mTOR (RAD001) inhibitors.Conclusions: AXL promotes resistance to WEE1 inhibition via downstream mTOR signaling and resulting activation of a parallel DNA damage repair pathway, CHK1. These findings suggest rational combinations to enhance the clinical efficacy of AZD1775, which is currently in clinical trials for SCLC and other malignancies. Clin Cancer Res; 23(20); 6239-53. ©2017 AACR.

Therapy of Small Cell Lung Cancer (SCLC) with a Topoisomerase-I-inhibiting Antibody-Drug Conjugate (ADC) Targeting Trop-2, Sacituzumab Govitecan

Purpose: We evaluated a Trop-2-targeting antibody conjugated with SN-38 in metastatic small cell lung cancer (mSCLC) patients.Experimental Design: Sacituzumab govitecan was studied in patients with pretreated (median, 2; range, 1-7) mSCLC who received either 8 or 10 mg/kg i.v. on days 1 and 8 of 21-day cycles. The primary endpoints were safety and objective response rate (ORR); duration of response, progression-free survival (PFS), and overall survival (OS) were secondary endpoints.Results: Sixty percent of patients showed tumor shrinkage from baseline CTs. On an intention-to-treat basis (N = 50), the ORR was 14% (17% for the 10-mg/kg group); the median response duration, 5.7 months; the clinical benefit rate (CBR ≥4 months), 34%; median PFS, 3.7 months; and median OS, 7.5 months. There was a suggested improvement in PR, CBR, and PFS with sacituzumab govitecan in second-line patients who were sensitive to first-line therapy, but no difference between first-line chemosensitive versus chemoresistant patients in the overall population. There was a statistically significant higher OS in those patients who received prior topotecan versus no topotecan therapy in a small subgroup. Grade ≥3 adverse events included neutropenia (34%), fatigue (13%), diarrhea (9%), and anemia (6%). Trop-2 tumor staining was not required for patient selection. No antibodies to the drug conjugate or its components were detected on serial blood collections.Conclusions: Sacituzumab govitecan appears to have a safe and effective therapeutic profile in heavily pretreated mSCLC patients, including those who are chemosensitive or chemoresistant to first-line chemotherapy. Additional studies as a monotherapy or combination therapy are warranted. Clin Cancer Res; 23(19); 5711-9. ©2017 AACR.

The Humanistic Burden of Small Cell Lung Cancer (SCLC): A Systematic Review of Health-Related Quality of Life (HRQoL) Literature

Background: Little is known about the humanistic burden of small cell lung cancer (SCLC), specifically the impact on health-related quality of life (HRQoL). The aim of this systematic literature review was to explore the impact of SCLC on HRQoL and the patient reported outcomes (PROs) used to capture this impact.

Methods: We conducted a systematic search of Medline®, Embase, and PsycINFO, oncology organization websites and conference proceedings within the past 10 years. Articles reporting HRQoL outcomes of SCLC patients were selected.

Results: Twenty-seven eligible publications were identified. Global or overall impact on HRQoL (n = 21) was reported most often, with considerably fewer reporting individual domains that comprise HRQoL. Results indicated that HRQoL was negatively impacted in SCLC patients in comparison to the normal population in most domains. Overall, the domains measuring physical functioning and activities of daily living were most impacted. However, results on cognitive and emotional functioning were inconclusive. The impact on HRQoL may be least in both limited disease and extensive disease (ED) SCLC patients who have responded to treatment, and greatest in ED patients who were treatment naïve. The most frequently used PROs were the EORTC QLQ-C30 core cancer instruments, the lung cancer specific module the EORTC QLQ-LC13, LCSS, and EQ-5D.

Conclusion: There exists a paucity of reporting on SCLC HRQoL outcomes. This extends to the reporting of domain level scores and by patient sub-group. Greater reporting at a granular level is recommended to allow for more robust conclusions to be made.

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.

Treatment advances in small cell lung cancer (SCLC)

Small cell lung cancer (SCLC) is an aggressive tumor characterized by rapid doubling time and high propensity for early development of disseminated disease. Although most patients respond to initial therapy with a platinum doublet, the majority of those with limited stage and virtually all patients with metastatic disease eventually develop tumor progression for which there are limited treatment options. There have been no recent changes in the treatment of SCLC, with platinum plus etoposide and topotecan as the standard first-line and second-line respectively, neither showing survival benefit over the combination of cyclophosphamide, doxorubicin and vincristine, which was developed in the 1970s. More recently, a new understanding of the biology of SCLC has led to the development of novel drugs, of which the most promising are the immune checkpoint inhibitors and the antibody drug conjugate rovalpituzumab tesirine.

Outcome and prognostic factors in patients with brain metastases from small-cell lung cancer treated with whole brain radiotherapy

The purpose of this study was to evaluate prognostic factors associated with overall survival (OS) and neurological progression free survival (nPFS) in small-cell lung cancer (SCLC) patients with brain metastases who received whole-brain radiotherapy (WBRT). From 2003 to 2015, 229 SCLC patients diagnosed with brain metastases who received WBRT were analyzed retrospectively. In this cohort 219 patients (95%) received a total photon dose of 30 Gy in 10 fractions. The prognostic factors evaluated for OS and nPFS were: age, Karnofsky Performance Status (KPS), number of brain metastases, synchronous versus metachronous disease, initial response to chemotherapy, the Radiation Therapy Oncology Group recursive partitioning analysis (RPA) class and thoracic radiation. Median OS after WBRT was 6 months and the median nPFS after WBRT was 11 months. Patients with synchronous cerebral metastases had a significantly better median OS with 8 months compared to patients with metachronous metastases with a median survival of 3 months (p < 0.0001; HR 0.46; 95% CI 0.31-0.67). Based on RPA classification median survival after WBRT was 17 months in RPA class I, 7 months in class II and 3 months in class III (p < 0.0001). Karnofsky performance status scale (KPS < 70%) was significantly associated with OS in both univariate (HR 2.84; p < 0.001) and multivariate analyses (HR 2.56; p = 0.011). Further, metachronous brain metastases (HR 1.8; p < 0.001), initial response to first-line chemotherapy (HR 0.51, p < 0.001) and RPA class III (HR 2.74; p < 0.001) were significantly associated with OS in univariate analysis. In multivariate analysis metachronous disease (HR 1.89; p < 0.001) and initial response to chemotherapy (HR 0.61; p < 0.001) were further identified as significant prognostic factors. NPFS was negatively significantly influenced by poor KPS (HR 2.56; p = 0.011), higher number of brain metastases (HR 1.97; p = 0.02), and higher RPA class (HR 2.26; p = 0.03) in univariate analysis. In this series, the main prognostic factors associated with OS were performance status, time of appearance of intracranial disease (synchronous vs. metachronous), initial response to chemotherapy and higher RPA class. NPFS was negatively influenced by poor KPS, multiplicity of brain metastases, and higher RPA class in univariate analysis. For patients with low performance status, metachronous disease or RPA class III, WBRT should be weighed against supportive therapy with steroids alone or palliative chemotherapy.

Meta-analysis of the role of bevacizumab in extensive stage small cell lung cancer

Progress in the treatment options for small cell lung cancer (SCLC) remains poor. Concerns exist regarding the efficacy of bevacizumab in SCLC. The present study aimed to evaluate the efficacy of bevacizumab in extensive stage (ES)-SCLC. A meta-analysis on studies conducted and listed on the Medline, Cochrane Trials, ASCO, ESMO and ClinicalTrial databases, and Chinese databases prior to April 2015 was performed. All clinical trials in which patients with ES-SCLC were treated with bevacizumab were considered. Survival rates at specific time points were extracted from the reported survival curves. Hazard ratios (HR) for progression-free survival (PFS) and overall survival (OS), rates for PFS, OS, overall response rate (ORR), and side-effects were synthesized using random-effects or fixed-effects model. Two randomized control trials (RCT) (176 patients) and six single-arm trials (292 patients) were identified. In RCTs, no statistically significant differences were observed in PFS [HR, 0.70; 95% confidence interval (CI), 0.41–1.19; P=0.19] or OS (HR, 1.21; 95% CI, 0.84–1.75; P=0.31). In the first-line trials, pooled 6-month and 1-year PFS rates were 57% (95% CI, 39–76%) and 10% (95% CI, 4–16%), respectively. Synthesized 1-year and 2-year OS rates were 45% (95% CI, 36–54%) and 10% (95% CI, 6–14%), respectively. Reported median PFS and OS times for pretreated patients were 2.7–4.0 months and 6.3–7.4 months, respectively. Pooled ORRs were 71% (95% CI, 59–82%) in the first-line trials and 18% (95% CI, 11–25%) in the second-line trials. The most common types of reported toxicities were chemotherapy-associated, including neutropenia, leukopenia, fatigue and thrombocytopenia. According to the RCTs, bevacizumab did not appear to improve the PFS or OS for patients with ES-SCLC, with low quality of evidence. Due to the disappointing pooled efficacy in the single-arm trials, more clinical studies on bevacizumab in SCLC may not be valuable, although the evidence was with low quality.

Second-line pazopanib in patients with relapsed and refractory small-cell lung cancer: a multicentre phase II study of the Hellenic Oncology Research Group

Background:

Pazopanib is a tyrosine kinase inhibitor with antiangiogenic activity. Vascular endothelial growth factor expression is increased in SCLC and is correlated with poor prognosis. The efficacy and tolerance of second-line pazopanib in SCLC was evaluated.

Patients and methods:

Patients with platinum-sensitive (cohort A; n=39) and -resistant/refractory (cohort B; n=19) SCLC were enrolled in a multicentre phase II study. The primary end point was the progression-free survival rate (PFS-R) at week 8 in each cohort. Pazopanib (800 mg per day per os) was administered until progressive disease (PD). Circulating tumour cells (CTCs) were enumerated using the Cellsearch assay.

Results:

All patients were evaluable for response and toxicity. In the intention-to-treat analysis, eight (13.8%) patients achieved partial response (PR) (95% confidence interval (CI): 5.0–22.7), 20 (34.5%) stable disease (SD) and 30 (51.7%) PD. Accrual in cohort B was halted because the hard-stop rule was met; in cohort A, the PFS-R was 59% (95% CI: 43.5–74.4; PR=7, SD=16). Nine (23.1%) patients received pazopanib for >6 months and 3 of them for >12 months. One pazopanib cycle resulted to a significant decrease to the number of patients with ⩾5 CTCs/7.5 ml of blood (20%) compared with baseline (50%). The median PFS and OS for all patients was 2.5 months (95% CI: 1.9–3.1 months) and 6.0 months (95% CI: 3.8–8.2 months), respectively (cohort A: PFS=3.7 months and OS=8.0 months). No unexpected toxicity was observed.

Conclusions:

Second-line treatment with pazopanib in platinum-sensitive SCLC is well tolerated and resulted in promising objective responses and disease control; CTC enumeration might serve as a reliable surrogate biomarker of response.

Thoracic radiation therapy could give survival benefit to elderly patients with extensive-stage small-cell lung cancer

AIM

To evaluate the effect of thoracic radiation therapy (TRT) in elderly patients (aged ≥65 years) with extensive-stage small-cell lung cancer (ES-SCLC).

PATIENTS & METHODS

This study reviewed the records of 118 elderly patients with ES-SCLC (all with distant metastasis) through January 2006-December 2013. The patients were divided into either a chemotherapy (ChT)/TRT-combination group or a ChT-alone group.

RESULTS

The median survival time and 3-year overall survival rates in the ChT/TRT group were significantly higher than those in the ChT-alone group (17.0 vs 11.7 months; 18.1 vs 14.9%; p = 0.014). The 3-year overall survival rates in patients who received prophylactic cranial irradiation were also higher than the rates in patients who did not receive prophylactic cranial irradiation (18.1 vs 5.1%; p = 0.708).

CONCLUSION

TRT combined with ChT could provide a survival benefit to elderly patients with ES-SCLC.

An open-label, phase II study of the polo-like kinase-1 (Plk-1) inhibitor, BI 2536, in patients with relapsed small cell lung cancer (SCLC)

OBJECTIVES

This phase II, open-label study was designed to evaluate the response rate to the polo-like kinase 1 (Plk-1) inhibitor BI 2536 in patients with sensitive-relapsed small cell lung cancer (SCLC). Secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of response, and safety.

MATERIALS AND METHODS

Patients were treated with the recommended phase II dose of 200mg of BI 2536 intravenously every 21days. This was a two-stage design with an early stopping rule in place if responses were not seen in at least 2 of the first 18 enrolled patients.

RESULTS AND CONCLUSION

Twenty-three patients were enrolled in the study and 21 patients were evaluable for response. No responses were observed and all 23 patients have progressed. The median PFS was 1.4 months. Treatment was generally well tolerated and the most frequent adverse events were neutropenia, fatigue, nausea, vomiting, and constipation. BI 2536 is not effective in the treatment of sensitive relapsed SCLC. The criteria for expanding the trial to the second stage were not achieved, and the study was terminated for a lack of efficacy.

Seeking New Approaches to Patients With Small Cell Lung Cancer

The fundamental approach to the treatment of small cell lung cancer (SCLC) has not changed in the last several decades, with most advances being restricted to improved radiation approaches. The standard first-line chemotherapy regimen in the United States and Europe remains cisplatin or carboplatin plus etoposide in the treatment of limited stage (LS-SCLC) and extensive stage (ES-SCLC) disease. Radiation therapy is administered to those patients with LS-SCLC, whose cancer is confined to the chest in a single tolerable radiation field. This article will summarize a number of exciting observations regarding the biology of SCLC and how a deeper understanding of newly integrated targets and target pathways may lead to new and better therapeutic approaches in the near future.

Molecular analysis of circulating tumor cells identifies distinct copy-number profiles in patients with chemosensitive and chemorefractory small-cell lung cancer

In most patients with small-cell lung cancer (SCLC)-a metastatic, aggressive disease-the condition is initially chemosensitive but then relapses with acquired chemoresistance. In a minority of patients, however, relapse occurs within 3 months of initial treatment; in these cases, disease is defined as chemorefractory. The molecular mechanisms that differentiate chemosensitive from chemorefractory disease are currently unknown. To identify genetic features that distinguish chemosensitive from chemorefractory disease, we examined copy-number aberrations (CNAs) in circulating tumor cells (CTCs) from pretreatment SCLC blood samples. After analysis of 88 CTCs isolated from 13 patients (training set), we generated a CNA-based classifier that we validated in 18 additional patients (testing set, 112 CTC samples) and in six SCLC patient-derived CTC explant tumors. The classifier correctly assigned 83.3% of the cases as chemorefractory or chemosensitive. Furthermore, a significant difference was observed in progression-free survival (PFS) (Kaplan-Meier P value = 0.0166) between patients designated as chemorefractory or chemosensitive by using the baseline CNA classifier. Notably, CTC CNA profiles obtained at relapse from five patients with initially chemosensitive disease did not switch to a chemorefractory CNA profile, which suggests that the genetic basis for initial chemoresistance differs from that underlying acquired chemoresistance.

Lesser Toxicities of Belotecan in Patients with Small Cell Lung Cancer: A Retrospective Single-Center Study of Camptothecin Analogs

Purpose. Topotecan and belotecan are camptothecin derivatives that are used to treat small cell lung cancer (SCLC). This study compared the toxicities and efficacies of belotecan and topotecan monotherapies in patients with SCLC. Methods. We retrospectively reviewed data from 94 patients with SCLC (with or without prior chemotherapy) who were treated using belotecan monotherapy (n = 59, 188 cycles) or topotecan monotherapy (n = 35, 65 cycles) between September 2003 and December 2011. Results. Thrombocytopenia occurred during 42% and 61.5% of the belotecan and topotecan cycles, respectively (p = 0.007). Significant differences between belotecan and topotecan were also observed for grade 4/5 lung infection (3.2% versus 10.8%, resp.; p = 0.003), all-grade headache (3.2% versus 10.8%, resp.; p = 0.017), and grade 4/5 increased liver enzymes (0.5% versus 4.6%, resp.; p = 0.023). The median TTPDs, CSSs, and OSs were 14 months and 11.6 months (p = 0.646), 10 months and 7 months (p = 0.179), and 34.5 months and 21.4 months (p = 0.914) after belotecan and topotecan monotherapy, respectively. Conclusions. Belotecan monotherapy may be safer than topotecan monotherapy in SCLC patients. And in terms of efficacy, belotecan could be comparable to topotecan monotherapy.

A Phase II Clinical Trial of CPI-613 in Patients with Relapsed or Refractory Small Cell Lung Carcinoma

Background

Small cell lung cancer (SCLC) is a common lung cancer which presents with extensive stage disease at time of diagnosis in two-thirds of patients. For treatment of advanced disease, traditional platinum doublet chemotherapy induces response rates up to 80% but with few durable responses. CPI-613 is a novel anti-cancer agent that selectively inhibits the altered form of mitochondrial energy metabolism in tumor cells.

Methods

We evaluated CPI-613 with a single-arm, open-label phase II study in patients with relapsed or refractory SCLC. CPI-613 was given at a dose of 3,000 mg/m2 on days 1 and 4 of weeks 1–3 of 4 week cycle. The primary outcome was response rate as assessed by CT imaging using RECIST v1.1 criteria. Secondary outcomes were progression-free survival (PFS), overall survival (OS), and toxicity. Twelve patients were accrued (median age 57yo) who had previously received between 1 and 4 lines of chemotherapy (median 1) for SCLC with a treatment-free interval of less than 60 days in 9 of the 12 patients.

Results

No complete or partial responses were seen. Ten patients (83%) progressed as best response and 2 (17%) were not evaluable for response. Median time to progression was 1.7 months (range 0.7 to 1.8 months). Eleven patients (92%) died with median overall survival of 4.3 months (range 1.2 to 18.2 months). The study was closed early due to lack of efficacy. Of note, three out of three patients who progressed after CPI-613 and were subsequently treated with standard topotecan then demonstrated treatment response with survival for 18.2, 7.4, and 5.1 months. We conducted laboratory studies which found synergy in-vitro for CPI-613 with topotecan.

Conclusions

Single agent CPI-613 had no efficacy in this study. Further study of CPI 613 in combination with a topoisomerase inhibitor is warranted.

Targeting angiogenesis in small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive and lethal malignancy. Despite high initial response rates to systemic chemotherapy, the disease eventually relapses; further treatment only modestly improves outcomes and overall survival (OS) for patients with extensive stage disease is less than one year. Little progress has been made during the past decades, with no new drugs approved. Consequently, the development of novel strategies is an unmet need. The inhibition of angiogenesis, a defining characteristic of cancer, has demonstrated modest efficacy in several human malignancies, including non-small cell lung cancer (NSCLC). However, results from clinical trials in SCLC have been disappointing, and no anti-angiogenic agent has received regulatory approval due to lack of clinical efficacy. The elucidation of underlying mechanisms responsible for tumor resistance to angiogenic therapy and the simultaneous blockade of multiple elements that play a role in angiogenesis need to be further explored.

Targeting the PD-1/PD-L1 axis in the treatment of lung cancer

In recent years major advances in the field of molecular profiling of non-small cell lung cancer led to the identification of targetable driver mutations and revolutionized the treatment of specific patient subsets. However, the majority of NSCLC tumors do not harbor these genomic events. On the other hand, current studies have confirmed an expanding role for immunotherapy in lung cancer and new agents, such as inhibitors of the programmed cell death-1 (PD-1)/programmed cell death ligand 1 (PD-L1) axis have been introduced in the treatment armamentarium. The monoclonal antibodies nivolumab and pembrolizumab targeting PD-1 resulted in superior survival when compared to standard second line chemotherapy within the context of randomized trials and received regulatory approval. Moreover, several other anti-PD-L1 antibodies have demonstrated encouraging preliminary efficacy and multiple clinical trials in various settings during the disease trajectory are currently underway. Early immunotherapy trials have also illustrated the potential of PD-1 blockade in small cell lung cancer treatment, a disease for which major advances in systemic therapy are lacking. The currently available clinical data on PD-1/PD-L1 inhibition in lung cancer are summarized in this review.