Irinotecan-based chemotherapy in extrapulmonary neuroendocrine carcinomas: survival and safety data from a multicentric Italian experience

Purpose Neuroendocrine carcinomas (NECs) are a rare subgroup of neuroendocrine neoplasms that occasionally originate from gastro-entero-pancreatic (GEP) tract. Evidence of the effectiveness of chemotherapy is scarce. Platinum plus Etoposide regimens are currently the standard treatment in first-line, while little data are available on second-line treatments. The aim of this study is to evaluate the efficacy and safety of irinotecan (IRI)-based chemotherapy in a series of extrapulmonary NECs. Methods Patients with NEC diagnosis treated at University Hospitals of Modena, Florence, Pisa, and European Institute of Oncology of Milan with an IRI-based regimen (FOLFIRI or XELIRI) after progression to a first-line platinum-based therapy were enrolled. Objective responses were assessed according to RECIST criteria. Progression-free survival (PFS) and overall survival (OS) were calculated. Results Thirty-four patients, 16 males, and 18 females, median age of 59 years (range 32-77), with metastatic NEC were included. Twenty-seven patients had Ki-67 >= 55% and four patients Ki-67 of <55% (for three patients data were not available). The median number of treatment cycles of the IRI-based regimen was 7.5 (range 1-16). Six partial responses (17.6%) and 9 stable diseases (26.5%) were observed, with a disease control rate of 44.1%. Median PFS and OS were 4.4 and 5.9 months, respectively. Neutropenia, anemia, and nausea were the only G3-G4 toxicities reported. Conclusions Despite the relatively small sample size, IRI-based therapy demonstrated to be a valid option for patients with pretreated extrapulmonary NEC.