E361: Peritoneal Carcinomatosis in the Elderly: Too Old for Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy (CRS/HIPEC)?

Introduction: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) has been established as an effective treatment modality for patients with peritoneal malignancies with significant improvement in overall survival. Despite an aging population, there are recommendations against this procedure in elderly patients as its postoperative outcomes are still unclear. To close this knowledge gap, we examined postoperative outcomes in patients 70 years of age or older.

Methods: We retrospectively analyzed a prospective two-institution database of patients with peritoneal malignancies undergoing CRS/HIPEC from 2011-2023. We analyzed outcomes including morbidity, mortality, and overall survival in patients 70 years or older at the time of diagnosis. We performed descriptive statistics to analyze population characteristics and Kaplan-Meier survival analysis for overall survival (OS), recurrence, and recurrence-free survival (RFS).

Results: Of the 12 patients identified, median age was 71 years (70-81), 67% were female, and 67% had an ECOG performance status of 0. Primary tumors included: appendiceal mucinous (33%), mesothelioma (16%), gastric (16%), and unknown primary (8%). Nine patients received neoadjuvant chemotherapy. Mean length of operation was 8.9 hours (7.6-10.5).  Mitomycin-C was the agent used in 75% of cases. Peritoneal cancer index (PCI) ranged from 4 to 18 with 82% achieving a completeness of cytoreduction score (CCR) of 0. Mean length of hospital stay was 10 days (4-23) with mean SICU admission of 5 days (2-14). Seven patients experienced postoperative Clavien-Dindo grade 1 complication, with only one patient experiencing grade three. The median follow up was 25 months with 2-year OS rate of 100% and total RFS of 50%. At the end of the follow up period, there were 2 deaths, 4 recurrences, and 50% of patients were alive with no evidence of disease.

Conclusions: In this cohort, CRS/HIPEC seems to be a safe and feasible surgical option in select elderly patients with peritoneal carcinomatosis. Careful patient selection and implementation of proper postoperative care can reduce risk of complications. Given a rapidly aging population requiring advanced oncologic care, further studies are required to elucidate better predictors of surgical outcomes and assess quality of life in this patient population.