Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Outcomes for Colorectal and Mesothelioma Peritoneal Metastases: A 12-year Study

BACKGROUND/AIM: Peritoneal surface malignancies, including colorectal peritoneal metastases (CRPM) and peritoneal mesothelioma (PM) carry poor prognoses. The advent of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has significantly altered the treatment landscape, offering selected patients the potential for prolonged survival and improved quality of life. This study evaluated perioperative and oncological outcomes following CRS and HIPEC for CRPM and PM at a single tertiary center. PATIENTS AND METHODS: A retrospective review was conducted using a prospectively maintained database (CALHN reference Q20160412) from 2012-2024 at the Queen Elizabeth Hospital, South Australia. RESULTS: A total of 67 CRS procedures on 62 patients with CRPM and 21 procedures on 19 patients with PM were performed. Complete cytoreduction (CC0/CC1) was achieved in 74.6% and 60.0% patients, respectively. Median overall survival for patients with CRPM was 25 months, with a 53% 2-year and a 23% 5-year survival rate. For patients with PM, the 2-year and 5-year overall survival was 58% and 33% respectively. In patients with CRPM, incomplete cytoreduction and high peritoneal carcinomatosis index were independently associated with poorer outcomes. CONCLUSION: In our 12-year experience, outcomes were primarily determined by cytoreduction completeness and disease burden, with long-term survival achievable through careful patient selection and specialized surgical care.