Resectability of Peritoneal Carcinomatosis: Learnings from a Prospective Cohort of 533 Consecutive Patients Selected for Cytoreductive Surgery

The aim of this study was to identify the risk factors and causes of unresectability in a large cohort of patients with peritoneal carcinomatosis (PC) selected for cytoreductive surgery (CRS), and to assess the contribution of the different imaging modalities to the patient-selection process. The pre- and intraoperative data of 533 consecutive patients with PC planned for CRS at a single institution were reviewed. All patients underwent computed tomography (CT) magnetic resonance imaging and/or positron emission tomography/CT within the 2 days prior to surgery. Among the 533 patients, 436 (82 %) underwent complete CRS, 86 (16 %) underwent exploratory laparotomy without CRS because of multiple small-bowel involvement (n = 31), invasion of different digestive segments (n = 15), an elevated PC index (n = 14), invasion of the mesenteric root (n = 12), or another cause (n = 14), and 11 (2 %) did not undergo laparotomy because of disease progression on preoperative imaging findings. On univariate analysis, elevated levels of tumor markers and a short delay between the last cycle of chemotherapy and the scheduled surgery were identified as predictors of unresectability for the colonic PC population, while a younger age was identified in patients with gastric PC. Multivariate analysis disclosed the use of neoadjuvant chemotherapy and a younger age as independent predictors of unresectability in the colonic PC population. The current modalities for the assessment of PC resectability, including functional imaging examinations, have a low impact on patient selection for CRS. New tools are needed to decrease the rate of open-close procedures.