Predictive factors of non-completion of cytoreductive surgery in colorectal peritoneal metastasis

Introduction: Cytoreductive surgery (CRS) ± hyperthermic intraperitoneal chemotherapy (HIPEC) is the only potentially curative treatment that can improve the survival prognosis for patients with peritoneal metastasis (PM) of colorectal origin. The main independent prognostic factors are extent of disease, as measured by the Peritoneal Cancer Index (PCI), and completion of CRS (CC-0 or R1). Despite thorough preoperative work-up for selection of surgical candidates, 20%-25 % of CRS procedures are stopped after exploration during laparotomy. These patients undergo "open-and-close" procedures associated with a risk of complications and without any benefit. The aim of this study was to identify preoperative predictors of non-resectability and/or non-completion of CRS in patients with colorectal PMs who were candidates for surgery.

Materials and methods: Retrospective, monocentric study including patients admitted for CRS ± HIPEC at the Jules Bordet Institute between January 01, 2010 and December 31, 2021. The preoperative epidemiological, pathological, clinical, radiological, and biological features of patients with unresectable disease were compared with those of patients treated with CRS.

Results: One hundred nineteen patients were included, 60 men and 59 women (median age 61 years). Twenty-one CRS procedures (17.65 %) were stopped during exploratory laparotomy. Statistically significant factors associated with non-completion were age (p = 0.0183), PCI (p = 0.0001), presence of sub/occlusive episode(s) prior to CRS (p = 0.0012), and multifocal-diffuse uptakes on PET-scan (p = 0.0017).

Conclusion: Almost 18 % of patients had an "open-and-close" procedure. PCI was the major determinant of non-completion of CRS. Other predictive factors of unresectability of colorectal PM were age, the presence of sub/occlusive episodes, and PET/CT with multiple peritoneal uptakes.