The Role of Near-Infrared Fluorescence Imaging in the Assessment of Peritoneal Carcinomatosis from Colorectal Cancer

Abstract

Peritoneal carcinomatosis (PC) is a severe oncological condition originating from the mesothelium or, more frequently, from gastrointestinal or gynecological tumors. The PC is believed to be a terminal phase of the oncological disease and, if left untreated, has a median survival of approximately 6 months after diagnosis. PC originating from colorectal cancer is often a metachronous disease, and only 10–15% of patients with colorectal cancer show PC at the time of primary diagnosis. However, the peritoneum is involved up to 50% of cases in patients with colorectal cancer who develop tumor recurrence after potentially curative surgery of the primary tumor; and in 10–35% of cases it is the only site of tumor recurrence. The only potentially curative treatment in primary and metastatic peritoneal carcinomatosis is cytoreductive surgery associated with intraperitoneal hyperthermic chemotherapy (HIPEC) with a 5-year survival rate of 30–48%, in selected cases. One of the most critical problems in PC treatment is represented by the correct diagnosis of the peritoneal nodules and identification of smaller lesions. In recent years, new technologies have allowed surgeons to cope better with these limits. Intraoperative fluoroscopy (FI) is a recently revised imaging modality that could improve PC detection. Indocyanine green (ICG), a near-infrared contrast agent that may become fluorescent, has been shown to selectively accumulate in the tumor tissue, thus increasing diagnostic detection of PC.