Peritoneal tunnels: A site at risk for treatment failure when performing treatments for peritoneal metastases. A case series of 2 patients

BACKGROUND: Peritoneal metastases from gastrointestinal cancer can be treated by a combination of surgery to remove visible evidence of disease and perioperative intraperitoneal chemotherapy to eradicate microscopic disease. Complete cytoreduction is necessary for long-term benefit. METHODS: Two sites for incomplete cytoreduction because tumor is hidden from visual inspection were identified. Patients who developed recurrence at these anatomic sites were studied. RESULTS: A peritoneal tunnel along a patent processus vaginalis allowed tumor to be sequestered along the inguinal canal in a female patient. A peritoneal tunnel beneath a hepatic bridge over the round ligament obscured mucinous tumor in a male patient. CONCLUSIONS: Peritoneal tunnels in the inguinal region or at the porta hepatis should be opened by surgical dissection so that all foci of peritoneal metastases are removed at a complete cytoreductive surgery and these sites treated with chemotherapy.