Outcome and Safety of Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC) +/- Intraoperative Radiation Therapy (IORT) in the Management of Peritoneal Sarcomatosis: A Real-World Experience

Background: Peritoneal sarcomatosis (PS) is an aggressive disease; cytoreductive surgery (CRS) could be curative. Can the addition of hyperthermic intraperitoneal chemotherapy (HIPEC) +/- intraoperative radiation therapy (IORT) overcome treatment failure with an overall survival benefit. Methods: Retrospective review of the medical records of patients with PS treated by CRS, HIPEC and IORT at a comprehensive cancer center in the period between 2011-2016. Results: Twenty-four patients were identified. Fifteen were men and their median age was 58 years. Liposarcoma was the most frequent diagnosis (50%). Cytoreduction completeness (CC) score 0/1 was achieved in 19 patients, with a median pathological peritoneal cancer index (pPCI) of 12. Intraoperative radiation therapy was given in 16 patients. Eight patients developed grade III-IV Clavien-Dindo post-operative complications and 1 patient died 5 days post operative. Adjuvant chemotherapy was received in 9 patients. After a median follow-up of 28.5 months, the median PFS was 20.7 months, while the estimated 2- and 4-year PFS were 37.1% and 19.1%, respectively. The median OS was 176.5 months and the estimated 2- and 4-year OS were 95.8% and 79.8%, respectively. In the univariate analysis, the PFS differed significantly according to the CC score only. The median PFS for patients with CC 0-1 was 23.8 vs. 8.8 months for those with CC 2-3 (p = 0.027). Conclusions: The addition of HIPEC and IORT to CRS in the management of PS is feasible and safe. Comparing our results to several studies, this multimodality approach seems to improve local and regional control rates. A larger cohort of patients is needed for further evaluation and to give a concrete conclusion.