Oncological Outcomes After Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) in the Treatment of Peritoneal Carcinomatosis

Background Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a new surgical technique for the treatment of initially unresectable peritoneal carcinomatosis (PC). Our objective was to assess its oncological outcomes. Methods Between July 2016 and September 2020, data from 100 PIPAC procedures with oxaliplatin or doxorubicin-cisplatin in 49 patients with PC (all etiologies) were analyzed. We studied the evolution of the peritoneal cancer index (PCI), the need for radical surgery (R0), and overall survival (OS). Results The patients' median age was 65 (59; 71) years, and 55.1% were women. Median PIPAC procedures per patient were 2 (1-3), and 28 (57.1%) underwent more than one PIPAC procedure. Median PCI at the first PIPAC was 19 (15-22). PCI decreased for 37%, remained stable for 29.6%, and increased for 33.4% patients. Four (8.3%) underwent radical R0 surgery after PIPAC. After a median follow-up of 16.1 months (1.5-90.1), the median overall survival from PC diagnosis was 29.1 months (14.8-34.3), with a median gastric and colorectal PC survival of 11.3 (7.2-34.3) and 29.1 months (16.1-31) respectively. Overall survival after the first PIPAC session was 11.6 months (6-17.3), with median survival after gastric and colorectal PCs being 6 (2.9-15.5) and 13.3 months (5-17.6), respectively. Stratification of patients according to the number of lines of systemic chemotherapy, PIPAC procedures, and the chronology of PC onset did not result in a significant difference in survival. Conclusion The OS was in line with the literature. PIPAC could delay oncological progression and improve survival. These encouraging results justify the ongoing and future evaluations of PIPAC by prospective randomized trials.