Long-term survival outcomes of cytoreductive surgery and perioperative intraperitoneal chemotherapy: Single-institutional experience with 1225 cases.

BACKGROUND AND OBJECTIVES: To review long-term survival outcomes of patients with Peritoneal metastasis (PM) who underwent colorectal cancer (CRS) and intraperitoneal chemotherapy (PIC). METHODS: Patients that underwent CRS, with or without PIC, from January 1996 to March 2018 at the Peritonectomy Unit of St. George Hospital, Sydney were retrospectively analyzed from a prospectively maintained database. RESULTS: The study comprised of 1225 cases, including 687 females (56.1%) and 538 males (43.9%). Diagnoses included CRC (n = 363), followed by HAMN (n = 317), LAMN (n = 297), mesothelioma (n = 101), ovarian cancer (n = 55), and others including gastric, sarcoma, and neuroendocrine tumor (n = 92). The median OS, 5- and 10-year survivals for CRC were 35 months, 33% and 8%, respectively. Patients with LAMN, in relative to HAMN, experienced a higher median OS, 5- and 10-year survivals (248 months vs 63 months; 82% vs 52% and 59% vs 28%). The median OS for mesothelioma was 60 months with 5- and 10-year survivals of 48% and 19%, respectively. In ovarian cancer, the median OS was 30 months with 5- and 10-year survivals of 26% and 10%, respectively. For the remaining histological diagnoses, median OS and 5-year survival were 28 months and 27%, respectively. CONCLUSION: Our large-cohort data showed that CRS/PIC can provide long-term survival benefit to patients with PM of gastrointestinal and ovarian origin.

Prevention of peritoneal recurrence in high-risk colorectal cancer and evidence of T4 status as a potential risk factor.

Peritoneal metastasis (PM) following primary resection of colorectal cancer is common. The combined use of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy has significantly improved the survival outcome of patients with colorectal PM (CRPM). Diagnosing and treating early PM is essential as its extent is correlated with poorer outcomes. There are two novel therapies - second-look surgery and synchronous hyperthermic intraperitoneal chemotherapy - that are proposed to prophylactically treat or intervene early in the disease process to reduce the incidence and adverse outcomes associated with PM. These strategies are limited to patients at high risk of developing CRPM, including those that had synchronous PM or ovarian metastases resected at primary tumour removal, or a perforated primary tumour. The data on advanced primary tumour (T4) as a prognostic factor for PM after primary resection suggest that T4a tumours are prognostically worse than T4b. This literature review outlines the evidence, feasibility and safety regarding the pre-emptive treatments, as well as the relevance of T4a tumours as a risk factor for metachronous CRPM.