Role of diagnostic laparoscopy in patients with suspicion of colorectal peritoneal metastases to evaluate suitability for cytoreductive surgery with hyperthermic intraperitoneal chemotherapy

Background: The aim of the present study was to determine the feasibility and safety of performing diagnostic laparoscopy (DLS) routinely in patients with suspicion of colorectal peritoneal metastases (PM) to evaluate suitability for cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS+ HIPEC). Methods: Data for consecutive patients who underwent DLS between 2012 and 2018 were extracted retrospectively from an institutional database. The primary outcome was the degree of visibility of the abdominal cavity during DLS. Good laparoscopic evaluation of the abdominal cavity was defined as visibility of at least the regions of the diaphragm, pelvis and small bowel. Secondary outcomes were reasons for perioperative exclusion for CRS+ HIPEC, major postoperative complications (Clavien-Dindo grade III or above) and difference in overall survival (OS) between patients deemed suitable or unsuitable for CRS+ HIPEC. Kaplan-Meier analyses were performed. Results: Some 184 patients were analysed. Good laparoscopic evaluation was possible in 138 patients (75.0 per cent), and 24 (13.0 per cent) had conversion to an open procedure. Ninety-three patients (50.5 per cent) were excluded for CRS+ HIPEC, most commonly because of absence of colorectal PM (34 patients, 37 per cent) or extensive disease (Peritoneal Cancer Index 20 or above) (33 patients, 35 per cent). Major complications occurred in five patients (2.7 per cent), with no postoperative deaths. Median OS was significantly decreased in patients who were excluded due to extensive disease (14 (95 per cent c.i. 10 to 18) months) compared with patients suitable for CRS+ HIPEC (36 (27 to 45) months) (P