FOLFIRINEC: a randomized phase II trial of mFOLFIRINOX vs platinum-etoposide for metastatic neuroendocrine carcinoma of gastroenteropancreatic or unknown origin

Selection of Chemotherapy in Advanced Poorly Differentiated Extra-Pulmonary Neuroendocrine Carcinoma

Extra-pulmonary poorly differentiated neuroendocrine carcinoma is rare, and evidence for treatment has been limited. In this article, the evidence behind the cytotoxic chemotherapy choices used for metastatic or unresectable EP-PD-NEC is reviewed. In the first-line setting, etoposide and platinum chemotherapy or irinotecan and platinum have been demonstrated to be equivalent in a large phase III trial. Questions remain regarding the optimal number of cycles, mode of delivery, and the precise definition of platinum resistance in this setting. In the second-line setting, FOLFIRI has emerged as an option, with randomized phase 2 trials demonstrating modest, but significant, response rates. Beyond this, data are extremely limited, and several regimens have been used. Heterogeneity in biological behaviour is a major barrier to optimal EP-PD-NEC management. Available data support the potential role of the Ki-67 index as a predictive biomarker for chemotherapy response. A more personalised approach to management in future studies will be essential, and comprehensive multi-omic approaches are required to understand tumour somatic genetic changes in relation to their effects on the surrounding microenvironment.

Managing Metastatic Extrapulmonary Neuroendocrine Carcinoma After First-Line Treatment

PURPOSE OF REVIEW

Extrapulmonary neuroendocrine carcinoma (EP-NEC) is a rare, aggressive malignancy that can arise from any organ and frequently presents with distant metastases. Advanced disease has a poor prognosis with median overall survival (OS) rarely exceeding 1 year even with systemic therapy. The management paradigm of advanced/metastatic EP-NEC has been extrapolated from small cell lung cancer (SCLC) and commonly consists of 1st line therapy with etoposide and platinum (cisplatin or carboplatin), followed by alternative cytotoxic regimens at the time of progression. Only a minority of patients are able to receive 2nd line therapy, and cytotoxics derived from the SCLC paradigm such as topotecan or lurbinectedin have very limited activity. We aimed to evaluate emerging therapeutic options in the 2nd and later lines and survey potential future developments in this space.

RECENT FINDINGS

After a long period of stagnation in treatment options and outcomes, more promising regimens are gradually being utilized in the 2nd line setting including systemic therapy combinations such as FOLFIRI, FOLFOX, modified FOLFIRINOX, CAPTEM, and, more recently, novel checkpoint inhibitors such as nivolumab and ipilimumab. Simultaneously, advances in the understanding of disease biology are helping to refine patient selection and identify commonalities between NEC and their sites of origin which may eventually lead to additional targeted therapy options. While many questions remain, contemporary developments give grounds for optimism that improved outcomes for EP-NEC will soon be within reach.

Bevacizumab plus FOLFIRI after failure of platinum-etoposide first-line chemotherapy in patients with advanced neuroendocrine carcinoma (PRODIGE 41-BEVANEC): a randomised, multicentre, non-comparative, open-label, phase 2 trial

BACKGROUND

There is no standard second-line treatment after platinum-etoposide chemotherapy for gastroenteropancreatic neuroendocrine carcinoma. We aimed to evaluate the efficacy of FOLFIRI plus bevacizumab, and FOLFIRI alone, in this setting.

METHODS

We did a randomised, non-comparative, open-label, phase 2 trial (PRODIGE 41-BEVANEC) at 26 hospitals in France. We included patients aged 18 years or older with locally advanced or metastatic gastroenteropancreatic neuroendocrine carcinoma or neuroendocrine carcinoma of unknown primary origin, documented progressive disease during or after first-line platinum-etoposide chemotherapy, and an Eastern Cooperative Oncology Group performance status of 0-2. Patients were randomly assigned (1:1; block size of three), without stratification, to receive FOLFIRI (irinotecan 180 mg/m², calcium folinate 400 mg/m² or levofolinate 200 mg/m², and fluorouracil 400 mg/m² bolus then 2400 mg/m² over 46 h) plus bevacizumab 5 mg/kg or FOLFIRI alone, intravenously, every 2 weeks until disease progression or unacceptable toxicity. Neither patients nor investigators were masked to group assignment. The primary outcome was overall survival at 6 months after randomisation, evaluated in the modified intention-to-treat population (all enrolled and randomly assigned patients who received at least one cycle of FOLFIRI). This study is now complete and is registered with ClinicalTrials.gov, NCT02820857.

FINDINGS

Between Sept 5, 2017, and Feb 8, 2022, 150 patients were assessed for eligibility and 133 were enrolled and randomly assigned: 65 to the FOLFIRI plus bevacizumab group and 68 to the FOLFIRI group. 126 patients (59 in the FOLFIRI plus bevacizumab group and 67 in the FOLFIRI group) received at least one cycle of FOLFIRI and were included in the modified intention-to-treat population, 83 (66%) of whom were male and 43 (34%) were female, and the median age of the patients was 67 years (IQR 58-73). The primary tumour location was colorectal in 38 (30%) of 126 patients, pancreatic in 34 (27%), gastro-oesophageal in 22 (17%), and unknown in 23 (18%). After a median follow-up of 25·7 months (95% CI 22·0-38·2), 6-month overall survival was 53% (80% CI 43-61) in the FOLFIRI plus bevacizumab group and 60% (51-68) in the FOLFIRI group. Grade 3-4 adverse events that occurred in at least 5% of patients were neutropenia (eight [14%] patients), diarrhoea (six [10%]), and asthenia (five [8%]) in the FOLFIRI plus bevacizumab group, and neutropenia (seven [10%]) in the FOLFIRI group. One treatment-related death (ischaemic stroke) occurred in the FOLFIRI plus bevacizumab group.

INTERPRETATION

The addition of bevacizumab did not seem to increase the benefit of FOLFIRI with regard to overall survival. FOLFIRI could be considered as a standard second-line treatment in patients with gastroenteropancreatic neuroendocrine carcinoma.

FUNDING

French Ministry of Health and Roche SAS.

Future therapeutic strategies in the treatment of extrapulmonary neuroendocrine carcinoma: a review

Neuroendocrine neoplasms (NENs) are rare malignancies arising most commonly in the gastrointestinal and bronchopulmonary systems. Neuroendocrine carcinomas (NECs) are a subgroup of NENs characterised by aggressive tumour biology, poor differentiation and dismal prognosis. Most NEC primary lesions arise in the pulmonary system. However, a small proportion arise outside of the lung and are termed extrapulmonary (EP)-, poorly differentiated (PD)-NECs. Patients with local or locoregional disease may benefit from surgical excision; however, this is often not an option, due to late presentation. To date, treatment has mirrored that of small-cell lung cancer, with platinum-etoposide forming the basis of first-line treatment. There is a lack of consensus in relation to the most effective second-line treatment option. Low incidence, an absence of representative preclinical models and a lack of understanding of the tumour microenvironment all present challenges to drug development in this disease group. However, progress made in elucidating the mutational landscape of EP-PD-NEC and the observations made in several clinical trials are paving the way towards improving outcomes for these patients. The optimisation and strategic delivery of chemotherapeutic interventions according to tumour characteristics and the utilisation of targeted and immune therapies in clinical studies have yielded mixed results. Targeted therapies that complement specific genetic aberrations are under investigation, including AURKA inhibitors in those with MYCN amplifications, BRAF inhibitors in those with BRAFV600E mutations and EGFR suppression, and Ataxia Telangiectasia and Rad3-related inhibitors in patients with ATM mutations. Immune checkpoint inhibitors (ICIs) have conferred promising results in several clinical trials, particularly with dual ICIs and in combination with targeted therapy or chemotherapy. However, further prospective investigations are required to elucidate the impact of programmed cell death ligand 1 expression, tumour mutational burden and microsatellite instability on response. This review aims to explore the most recent developments in the treatment of EP-PD-NEC and contribute towards the requirement for clinical guidance founded on prospective evidence.

Second-line treatment and prognostic factors in neuroendocrine carcinoma: the RBNEC study

Neuroendocrine carcinomas (NEC) are aggressive malignant diseases. Etoposide-based rechallenge (EBR) and the prognostic role of RB transcriptional corepressor 1 (RB1) status in second-line chemotherapy (2L) have not been studied. The objectives of this study were to report the results of 2L including EBR as well as prognostic factors in a national retrospective multicentre study. NEC patients treated with 2L and further, with tissue samples available, were included. RB1 status and morphological classification were reviewed centrally. Among the 121 NEC patients (40% female, median age 61 years) included, there were 73 small-cell NEC (60%), 34 large-cell NEC (28%) and 14 NEC (not otherwise specified, 12%). Primary sites were lung (39%), gastroenteropancreatic (36%), other (13%) and unknown (12%). Median Ki-67 index was 80%. Median progression-free survival (PFS) and overall survival (OS) under 2L were 2.1 and 6.2 months, respectively. No difference was observed between patients who received an 'adenocarcinoma-like' or a 'neuroendocrine-like' 2L or according to the RB1 status. Thoracic NEC primary was the only adverse prognostic factor for OS. EBR, administered to 31 patients, resulted in a 62% disease control rate with a median PFS and OS of 3.2 and 11.7 months, respectively. In the 94 patients with a relapse-free interval of ≥3 months after first-line platinum-etoposide chemotherapy, the median OS was 12 months in patients who received EBR as compared to 5.9 months in patients who did not (P = 0.043). EBR could be the best 2L option for patient with initial response to first-line platinum-etoposide lasting at least 3 months. RB1 status does not provide prognostic information in this setting.

Prognostic factors of metastatic neuroendocrine carcinoma under first-line treatment with platinum etoposide with a focus on NEC score and Rb expression: Results from the multicentre RBNEC study of the Groupe d'Etude des Tumeurs Endocrines (GTE) and the ENDOCAN-RENATEN network

INTRODUCTION AND AIM

Neuroendocrine carcinomas (NECs) are aggressive malignant diseases. Platinum-etoposide (PE) combination is the standard first-line treatment, whatever the primary location. The NEC score and also retinoblastoma protein (Rb) status have been suggested to be predictive/prognostic factors in NEC. The primary objective of our multicentric retrospective study was to evaluate the prognostic relevance of the NEC score and Rb status, assessed by immunohistochemistry in PE-treated patients with metastatic NEC.

METHODS

Seven centres participated. The inclusion criteria were NEC, whatever the primary site, metastatic stage, first-line treatment with PE and tissue samples available. Rb status was determined centrally.

RESULTS

We report multicentric data from 185 metastatic patients (37% women, median age 63). There were 108 small-cell NECs (SCNECs, 58.4%), 50 large-cell NECs (LCNECs, 27%) and 27 not otherwise specified NECs (nosNECs, 14.6%). The primary sites were the thorax (37%), gastroenteropancreatic sites (38%), unknown (15%) and other (9%). The mean Ki-67 index was 76% (range 20-100). Rb status was interpretable in 122 cases. Rb expression was lost in 74% of the cases: 84% of SCNEC vs. 60% and 63% of LCNEC and nosNEC, respectively (p = 0.016). Objective response was seen in 70% of SCNEC, 45% of LCNEC and 48% of nosNEC (p < 0.001) and in 62% of Rb-negative tumours vs. 46% of Rb-positive tumours (p = 0.3). There was no difference in median progression-free survival or overall survival (OS) as per Rb status. Age, NEC score and response to chemotherapy were the main factors associated with OS in our cohort.

CONCLUSION

In our series, Rb status had no prognostic impact in PE-treated metastatic patients with NEC, whereas age, NEC score and response to chemotherapy were the main factors associated with OS.