Evaluation Of Predictive Biomarkers Of Response And Prognosis In Patients With High-Grade Extrapulmonary Neuroendocrine Carcinomas Treated With Platin-Based Chemotherapy.

e15183 Background: High-grade extrapulmonary neuroendocrine carcinomas (EPNEC) comprise a rare, aggressive and heterogeneous group of neoplasms. Most patients (pts) are metastatic and have shorter survival compared with others neuroendocrine tumors. Tissues markers could help tailoring systemic therapy to improve response rate (RR) to chemotherapy (Cx) and overall survival (OS). Methods: We conducted a retrospective analysis of pts with advanced high-grade EPNECs treated with platinum-based chemotherapy. Pts had their paraffin-embedded tumor tissues tested for Ki67, ERCC-1, BCL2 and Lin-28a by immunohistochemistry (IHC). All samples were reviewed by the same pathologist (R.S.S.M.). A final H-score was obtained multiplying the intensity of positive staining (0-3) by the percentage of positive cells (0-100), ranging 0-300. A H-score u003e = 200 was considered positive. Biomarkers were analyzed as both categorical and continuous variables. A cut of 55% was used to test Ki67 expression as a categorical variable. ...