Oncologic outcomes after splenectomy during initial cytoreductive surgery in advanced epithelial ovarian cancer: a nationwide population-based cohort study.

INTRODUCTION:Epithelial ovarian cancer (EOC) patients undergoing splenectomy during cytoreductive surgery represent a small subgroup of patients. Splenic metastases or technical reasons due to extensive upper abdominal disease may require a splenectomy. It has been hypothesized that as the spleen's antitumor immunologic functions may inhibit cancer growth, splenectomy may promote the growth of residual disease as observed in other cancer types of murine studies. The few studies assessing the impact of splenectomy on the oncologic outcomes of advanced stage EOC patients have reported inconsistent results. It remains unclear whether splenectomy during cytoreductive surgery is justified to achieve complete cytoreduction. The aim of this study was to assess the impact of a splenectomy on perioperative outcomes and survival of advanced stage EOC patients. MATERIAL AND METHODS:In this nationwide population-based study, all consecutive patients diagnosed with FIGO stage IIIC and IV EOC between 1 January 2008 and 31 December 2015 were identified from the Netherlands Cancer Registry. Patients who underwent cytoreductive surgery combined with platinum-based chemotherapy as primary treatment were selected. Differences in clinicopathologic characteristics between splenectomy and non-splenectomy patients were assessed. Progression-free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier survival curves and log-rank tests. Cox proportional hazards models were used to adjust for covariates that influence survival. RESULTS:A total of 3911 patients were identified: 99 splenectomy and 3812 non-splenectomy patients. Splenectomy patients were more likely to undergo extensive surgery or surgical reintervention, to receive intraperitoneal chemotherapy, intraoperative and postoperative blood transfusion, to experience postoperative infections, and to be admitted to an intensive care unit (all p < 0.002). No significant differences in PFS or OS were observed between splenectomy vs non-splenectomy patients after adjusting for covariates. CONCLUSIONS:Although advanced stage EOC patients who undergo splenectomy during cytoreductive surgery have less favorable perioperative outcomes, no adverse impact of splenectomy on the survival of advanced stage EOC patients was observed. Splenectomy during cytoreductive surgery seems to be justified to achieve complete cytoreduction in advanced stage EOC patients.