Preoperative computed tomography and selection of patients with colorectal peritoneal carcinomatosis for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

Aim A survival benefit has been observed for colorectal cancer patients with peritoneal carcinomatosis treated by cytoreductive surgery with intraoperative hyperthermic intraperitoneal chemotherapy (HIPEC). However, this treatment modality is associated with a considerable morbidity and mortality and in a significant number of patients survival is not improved. We studied whether poor survivors could be identified on preoperative computed tomography (CT), in order to avoid unnecessary surgery. Patients and methods Films of abdominopelvic CT scans from 25 such patients treated by cytoreductive surgery and HIPEC were retrospectively analysed by two radiologists separately. A simplified peritoneal cancer index (SPCI) was used to determine the extent of peritoneal involvement. Correlation between the on preoperative CT based SPCI-scores as well as number of involved abdominopelvic areas (N) and survival was examined with the log-rank test. The relation between each affected region and survival was evaluated with Cox regression analysis. Results The preoperative SPCI- and N-scores of one of the radiologists had no statistically significant prognostic value, while for the second radiologist SPCI≥7 and N≥4 were associated with particularly poor outcome. Additionally, the presence of ileocaecal region involvement and, depending on the radiologist, the occurrence of tumour deposits in the left subdiaphragmatic area on CT appeared to be unfavourable prognostic signs. Conclusions The prognostic value of preoperative conventional CT appeared to be radiologist dependent and may, therefore, be of limited value in selecting colorectal cancer patients with peritoneal carcinomatosis who will not benefit from extensive cytoreductive surgery followed by HIPEC.