Stage IV lung carcinoids: spectrum and evolution of proliferation rate, focusing on variants with elevated proliferation indices.

The spectrum and evolution of proliferation rates in stage IV lung carcinoids is poorly defined. In particular, there are limited data on the prevalence and characteristics of tumors exceeding the standard upper proliferative criteria-as defined largely based on early-stage carcinoids-in metastatic setting. Sixty-six patients with stage IV lung carcinoids were identified, and all evaluable samples (n = 132; mean 2 samples per patient) were analyzed for mitotic counts and Ki-67 rate. Clinicopathologic and genomic features associated with elevated proliferation rates (>10 mitoses per 2 mm2 and/or >20% hot-spot Ki-67), and evolution of proliferation rates in serial specimens were analyzed. We found that mitoses and/or Ki-67 exceeded the standard criteria in 35 of 132 (27%) samples, primarily (31/35 cases) at  metastatic sites. Although neuroendocrine neoplasms with >10 mitoses per 2 mm2 are currently regarded as de facto neuroendocrine carcinomas, the notion that these cases are part of the spectrum of carcinoids was supported by (1) well-differentiated morphology, (2) conventional proliferation rates in other samples from same patient, (3) genetic characteristics, including the lack of RB1/TP53 alterations in all tested samples (n = 19), and (4) median overall survival of 2.7 years, compared to <1 year survival of stage IV neuroendocrine carcinomas in the historic cohorts. In patients with matched primary/metastatic specimens (48 pairs), escalation of mitoses or Ki-67 by ≥10 points was observed in 35% of metastatic samples; clonal relationship in one pair with marked proliferative progression was confirmed by next-generation sequencing. Notably, escalation of proliferation rate was documented in a subset of metastases arising from resected typical carcinoids, emphasizing that the diagnosis of typical carcinoid in primary tumor does not assure low proliferation rate at metastatic sites. In conclusion, stage IV lung carcinoids frequently exceed the standard proliferative criteria established for primary tumors, and commonly exhibit proliferative escalation at metastatic sites. Despite the overlap of proliferation rates, these tumors show fundamental morphologic, genomic and clinical differences from neuroendocrine carcinomas, and should be classified separately from those tumors. Awareness of the increased proliferative spectrum in metastatic carcinoids is critical for their accurate diagnosis. Further studies are warranted to explore the impact of proliferation indices on prognosis and therapeutic responses of patients with metastatic carcinoids.

Efficacy and safety of bevacizumab in active brain metastases from non-small cell lung cancer.

Bevacizumab is effective for the treatment of non-small cell lung cancer (NSCLC). Ongoing trials are exploring the safety of bevacizumab in patients with inactive, previously treated brain metastases. However, bevacizumab safety and efficacy in the treatment of active brain metastases is unknown. Bevacizumab received accelerated FDA approval for progressive glioblastoma, a primary brain tumor, because of high response rates and low incidence of intracranial hemorrhage. We retrospectively identified patients treated with bevacizumab for active (treatment naïve or progressive) central nervous system (CNS) metastases from NSCLC. MRI scans performed at least 6 weeks after initiating bevacizumab were assessed for response. There were six patients, four women and two men with a median age of 60 years (range 59-77) at initiation of bevacizumab. Five patients had progressive CNS metastases despite prior treatment including surgery, radiotherapy, and/or chemotherapy; one patient had treatment-naïve brain metastases. Two patients had leptomeningeal metastases, isolated or coexistent with parenchymal brain metastases in one patient each. Bevacizumab was administered alone to one patient and in combination with various cytotoxic chemotherapies in the others. Toxicity included an asymptomatic (Grade 1) intra-tumoral hemorrhage which occurred in one of three patients receiving concurrent anticoagulation with bevacizumab. There was no recurrent CNS bleeding in two patients with a prior history of such hemorrhage. Best CNS response (RECIST) was partial in two, stable disease in three, and progression in one. Median progression-free survival (PFS) was 7.8 months and median overall survival (OS) was 14.1 months following initiation of bevacizumab. Clinical benefit was also observed in the form of improved symptoms and reduced corticosteroid requirements. Bevacizumab should be used with caution in patients with active CNS metastases pending additional safety data. This series suggests bevacizumab may be safe and effective for progressive brain metastases from NSCLC and deserves further study.

Targeting the differential addiction to anti-apoptotic BCL-2 family for cancer therapy.

BCL-2 family proteins are central regulators of mitochondrial apoptosis and validated anti-cancer targets. Using small cell lung cancer (SCLC) as a model, we demonstrated the presence of differential addiction of cancer cells to anti-apoptotic BCL-2, BCL-XL or MCL-1, which correlated with the respective protein expression ratio. ABT-263 (navitoclax), a BCL-2/BCL-XL inhibitor, prevented BCL-XL from sequestering activator BH3-only molecules (BH3s) and BAX but not BAK. Consequently, ABT-263 failed to kill BCL-XL-addicted cells with low activator BH3s and BCL-XL overabundance conferred resistance to ABT-263. High-throughput screening identified anthracyclines including doxorubicin and CDK9 inhibitors including dinaciclib that synergized with ABT-263 through downregulation of MCL-1. As doxorubicin and dinaciclib also reduced BCL-XL, the combinations of BCL-2 inhibitor ABT-199 (venetoclax) with doxorubicin or dinaciclib provided effective therapeutic strategies for SCLC. Altogether, our study highlights the need for mechanism-guided targeting of anti-apoptotic BCL-2 proteins to effectively activate the mitochondrial cell death programme to kill cancer cells.

Large Cell Neuroendocrine Carcinoma of the Lung: Clinico-Pathologic Features, Treatment, and Outcomes.

BACKGROUND: Large cell neuroendocrine carcinoma (LCNEC) accounts for approximately 3% of lung cancers. Pathologic classification and optimal therapies are debated. We report the clinicopathologic features, treatment and survival of a series of patients with stage IV LCNEC. MATERIALS AND METHODS: Cases of pathologically-confirmed stage IV LCNEC evaluated at Memorial Sloan Kettering Cancer Center from 2006 to 2013 were identified. We collected demographic, treatment, and survival data. Available radiology was evaluated by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1 criteria. RESULTS: Forty-nine patients with stage IV LCNEC were identified. The median age was 64 years, 63% of patients were male, and 88% were smokers. Twenty-three patients (n = 23/49; 47%) had brain metastases, 17 at diagnosis and 6 during the disease course. Seventeen LCNEC patients (35%) had molecular testing, of which 24% had KRAS mutations (n = 4/17). Treatment data for first-line metastatic disease was available on 37 patients: 70% (n = 26) received platinum/etoposide and 30% (n = 11) received other regimens. RECIST was completed on 23 patients with available imaging; objective response rate was 37% (95% confidence interval, 16%-62%) with platinum/etoposide, while those treated with other first-line regimens did not achieve a response. Median overall survival was 10.2 months (95% confidence interval, 8.6-16.4 months) for the entire cohort. CONCLUSION: Patients with stage IV LCNEC have a high incidence of brain metastases. KRAS mutations are common. Patients with stage IV LCNEC do not respond as well to platinum/etoposide compared with historic data for extensive stage small-cell lung cancer; however, the prognosis is similar. Prospective studies are needed to define optimum therapy for stage IV LCNEC.

Next-Generation Sequencing of Pulmonary Large Cell Neuroendocrine Carcinoma Reveals Small Cell Carcinoma-like and Non-Small Cell Carcinoma-like Subsets.

PURPOSE: Pulmonary large cell neuroendocrine carcinoma (LCNEC) is a highly aggressive neoplasm, whose biologic relationship to small cell lung carcinoma (SCLC) versus non-SCLC (NSCLC) remains unclear, contributing to uncertainty regarding optimal clinical management. To clarify these relationships, we analyzed genomic alterations in LCNEC compared with other major lung carcinoma types. EXPERIMENTAL DESIGN: LCNEC (n = 45) tumor/normal pairs underwent targeted next-generation sequencing of 241 cancer genes by Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) platform and comprehensive histologic, immunohistochemical, and clinical analysis. Genomic data were compared with MSK-IMPACT analysis of other lung carcinoma histologies (n = 242). RESULTS: Commonly altered genes in LCNEC included TP53 (78%), RB1 (38%), STK11 (33%), KEAP1 (31%), and KRAS (22%). Genomic profiles segregated LCNEC into 2 major and 1 minor subsets: SCLC-like (n = 18), characterized by TP53+RB1 co-mutation/loss and other SCLC-type alterations, including MYCL amplification; NSCLC-like (n = 25), characterized by the lack of coaltered TP53+RB1 and nearly universal occurrence of NSCLC-type mutations (STK11, KRAS, and KEAP1); and carcinoid-like (n = 2), characterized by MEN1 mutations and low mutation burden. SCLC-like and NSCLC-like subsets revealed several clinicopathologic differences, including higher proliferative activity in SCLC-like tumors (P < 0.0001) and exclusive adenocarcinoma-type differentiation marker expression in NSCLC-like tumors (P = 0.005). While exhibiting predominant similarity with lung adenocarcinoma, NSCLC-like LCNEC harbored several distinctive genomic alterations, including more frequent mutations in NOTCH family genes (28%), implicated as key regulators of neuroendocrine differentiation. CONCLUSIONS: LCNEC is a biologically heterogeneous group of tumors, comprising distinct subsets with genomic signatures of SCLC, NSCLC (predominantly adenocarcinoma), and rarely, highly proliferative carcinoids. Recognition of these subsets may inform the classification and management of LCNEC patients. Clin Cancer Res; 22(14); 3618-29. ©2016 AACR.

Neoadjuvant and adjuvant chemotherapy in resected pulmonary large cell neuroendocrine carcinomas: a single institution experience.

BACKGROUND: Pulmonary large cell neuroendocrine carcinomas (LCNEC) are aggressive neoplasms with poor prognosis. The role of neoadjuvant and adjuvant therapies in these tumors remains uncertain. METHODS: We performed a retrospective review of a prospective database. Kaplan-Meier estimates of overall survival (OS) were determined and compared across prognostic factors using log-rank analysis and the Cox proportional hazards model. RESULTS: One hundred patients with resected LCNEC were identified from 1992 to 2008. Of these, 54% were male and 98% current or former smokers (mean 60.3 pack-years). Twenty-two patients received neoadjuvant platinum chemotherapy with a response rate of 68% (15 of 22). Eighty percent (80 of 100) underwent lobectomy and 11% (11 of 100) pneumonectomy with a 90% (90 of 100) complete resection (R0) rate. Seventy-one percent (71 of 100) were stage I-II, and 20 of 71 received platinum adjuvant chemotherapy. Mean OS was 40 months. Univariate factors associated with decreased OS included male gender (p = 0.007), increasing tumor (T) stage (p = 0.004), and stage III-IV disease (p = 0.04). Stage IB patients fared significantly worse than IA (p = 0.006). Multivariate analyses identified male gender (hazard ratio [HR] 2.3, p = 0.007), comorbid pulmonary disease (HR 2.3, p = 0.012), and pathologic stage (HR = 2.2, p = 0.011) as associated with risk of death. Univariate analysis in stage IB-IIIA completely resected (R0) patients receiving combination platinum-based induction and (or) adjuvant chemotherapy showed a trend toward improved OS (median survival 7.4 vs 2 years, p = 0.052). CONCLUSIONS: The LCNEC has a high response rate to platinum-based neoadjuvant chemotherapy. Resected advanced-stage patients receiving combination neoadjuvant and (or) adjuvant chemotherapy may have a survival advantage. These therapies should be considered in resectable patients with LCNEC.

A phase II study of obatoclax mesylate, a Bcl-2 antagonist, plus topotecan in relapsed small cell lung cancer.

INTRODUCTION: We previously reported data on the safety, tolerability, and recommended phase II dose of obatoclax mesylate in conjunction with topotecan in patients with advanced solid tumor malignancies. Preliminary efficacy data suggested activity in patients with recurrent small cell lung cancer (SCLC). Based on these data, we performed a phase II study of obatoclax mesylate plus topotecan in patients with relapsed SCLC to assess efficacy. METHODS: This was an open-label, single-arm, phase II extension of obatoclax mesylate plus topotecan in patients with relapsed SCLC. Obatoclax mesylate was given intravenously (IV) at a dose of 14mg/m(2) on days 1 and 3 with IV topotecan at 1.25mg/m(2) on days 1-5 of an every 3-week cycle. The primary end-point of this study was overall response rate. RESULTS: Nine patients with recurrent SCLC were enrolled into the first stage of the study. Patients received a median of 2 cycles of treatment. All patients were evaluable for the primary end-point of overall response. There were no partial or complete responses. Five patients (56%) had stable disease. The remaining four patients (44%) developed progressive disease. The most common grade 3 or 4 adverse events included thrombocytopenia (22%), anemia (11%), neutropenia (11%), and ataxia (11%). CONCLUSION: Obatoclax mesylate added to topotecan does not exceed the historic response rate seen with topotecan alone in patients with relapsed SCLC following the first-line platinum-based therapy.

Phase II trial of gefitinib and everolimus in advanced non-small cell lung cancer.

INTRODUCTION: Concurrent signal transduction inhibition with the epidermal growth factor receptor (EGFR) inhibitor gefitinib and the mammalian target-of-rapamycin inhibitor everolimus has been hypothesized to result in enhanced antitumor activity in patients with non-small cell lung cancer (NSCLC). This phase II trial assessed the efficacy of the combination of gefitinib and everolimus in patients with advanced NSCLC. METHODS: Two cohorts of 31 patients with measurable stage IIIB/IV NSCLC were enrolled: (1) no prior chemotherapy and (2) previously treated with cisplatin or carboplatin and docetaxel or pemetrexed. All patients received daily everolimus 5 mg and gefitinib 250 mg. Response was assessed after 1 month and then every 2 months. Pretreatment tumor specimens were collected for mutation testing. RESULTS: Sixty-two patients were enrolled (median age: 66 years, 50% women, 98% stage IV, all current/former smokers, and 85% adenocarcinoma). Partial responses were seen in 8 of 62 patients (response rate: 13%; 95% confidence interval: 5-21%); five responders had received no prior chemotherapy. Three partial responders had an EGFR mutation. Both patients with a KRAS (G12F) mutation responded. The median time to progression was 4 months. Median overall survival was 12 months, 27 months for no prior chemotherapy patients, and 11 months for patients previously treated with chemotherapy. CONCLUSIONS: The 13% partial response rate observed did not meet the prespecified response threshold to pursue further study of the combination of gefitinib and everolimus. The response rate in patients with non-EGFR mutant tumors was 8%, likely reflecting activity of everolimus. Further investigation of mammalian target-of-rapamycin inhibitors in patients with NSCLC with KRAS G12F-mutated tumors is warranted.