Predictive and prognostic survival factors in peritoneal carcinomatosis from appendiceal cancer after cytoreductive surgery with hyperthermic intraperitoneal chemotherapy.

BACKGROUND: Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) has survival benefit in the treatment of selected patients with peritoneal carcinomatosis (PC) from appendiceal cancer (AC). We evaluated factors affecting the survival of patients with PC from AC after CRS/HIPEC.
METHODS: A retrospective analysis of 387 CRS/HIPEC procedures performed between February 1998 and February 2013 identified 202 patients with PC from AC. Tumor histopathology, complete cytoreduction (CC 0-1), Peritoneal Cancer Index (PCI), and lymph node (LN) status were related to overall survival (OS) and progression-free survival (PFS) using the Kaplan-Meier method.
RESULTS: Overall, 129 women (64 %) and 73 men (36 %), mean age 54 years (range 25-81), with a mean follow-up of 36 months were included in the study. Seventy-seven low-grade tumors (disseminated peritoneal adenomucinosis [DPAM]; 38 %) and 125 high-grade tumors (peritoneal mucinous carcinomatosis [PMCA]; 62 %) were identified. Five- and 10-year OS was 56 % and 47 %, respectively, with PFS of 44 % at 5 and 10 years. Five-year OS in DPAM patients was 83 %, with a 5-year OS significant difference related to CC 0-1 versus CC 2-3 (incomplete cytoreduction) [p = 0.021]. Five-year OS in PMCA patients was 41 %, with a 5-year OS significant difference related to CC 0-1 versus CC 2-3 (p < 0.001), PCI <20 versus PCI ≥20 (p = 0.002), and (-)LN versus (+)LN (p < 0.001). Grade III/IV complications were 16 %. No perioperative mortality was reported.
CONCLUSION: Positive LN, PMCA histopathology, and PCI ≥20 are negative prognostic factors, while CC 0-1 is a positive survival predictor in PC from AC treated with CRS/HIPEC. However, in patients with PMCA and PCI ≥20 in whom CC 0-1 was a potential outcome should not be denied CRS/HIPEC.