Objective: The aim of this study was to evaluate the role of fluorescence imaging (FI) using an intraoperative injection of free indocyanine green (ICG) in the detection of peritoneal metastases (PM) due to colorectal cancer (CRC). Background: A large proportion of patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy will have local recurrence. This is, in part, related to the presence of small undetected nodules in the peritoneal cavity. Near-infrared FI-guided surgery has provided new opportunities for detection of nonvisible lesions during cancer surgery. Methods: Patients with PM from CRC admitted for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy were selected for participation in this study (NCT02032485). Free ICG, at 0.25 mg/kg of patient weight, was intravenous (IV)-injected intraoperatively. Tumor-to-background ratio was calculated for all suspect resected PM. Results: Sixty-three of 78 peritoneal resected nodules in 14 patients were evaluated for fluorescence, among them, 53 were malignant (84%) and 10 benign (16%). Twenty-six were hypofluorescent, 16 moderately hyperfluorescent, and 21 hyperfluorescent. Amongst the 42 nodules of the 9 patients with nonmucinous adenocarcinoma, the mean tumor-to-background ratio was 1.92 (SD 0.67) in malignant and 1.02 (SD 0.06) in benign nodules (P = 0.0099). In 4 of 14 patients (29%), the surgery was modified by intraoperative ICG-FI, which detected additional PM not found using visualization and palpation. Conclusions: This pilot study demonstrates that non-mucinous PM of CRC can be visualized intraoperatively using ICG-FI. Furthermore, ICG-FI findings resulted in modification of the planned surgery in 29% of patients.

Background: The purpose of this study was to report the pharmacokinetics (PK) and tolerance profile of intraoperative intraperitoneal chemo-hyperthermia (IPCH) with oxaliplatin and irinotecan. Patients and methods: Thirty-nine patients with peritoneal carcinomatosis (PC) of either gastrointestinal or peritoneal origin underwent complete cytoreductive surgery followed by IPCH with a stable dose of oxaliplatin (460 mg/m²), plus one among seven escalating doses of irinotecan (from 300 to 700 mg/m²). IPCH was carried out with the abdomen open, for 30 min at 43°C, with 2 l/m² of a 5% dextrose instillation in a closed continuous circuit. Patients received intravenous leucovorin (20 mg/m²) and 5-fluorouracil (400 mg/m²) just before IPCH to maximize the effect of oxaliplatin and irinotecan. Results: Irinotecan concentration in tumoral tissue increased until 400 mg/m² and then remained stable despite dose escalations. It was 16–23 times higher than in non-bathed tissues. Increasing doses of intraperitoneal irinotecan did not modify the PK of intraperitoneal oxaliplatin, and the drug concentration ratio was 17.8 higher in tumoral tissue (bathed) than in non-bathed tissues. The hospital mortality rate was 2.5% and the non-hematological complication rate was 25%. However, grade 3–4 hematological toxicity rate was 58%. Conclusion: Intraperitoneal heated oxaliplatin (460 mg/m²) plus irinotecan (400 mg/m²) presented an advantageous PK profile and was tolerated by patients, despite a high hematological toxicity rate.