Neglected prognostic importance of ileal resection in patients with peritoneal metastasis

We aimed to determine the prognostic role of ileal resection on postoperative complications and the final oncological results of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) treatment in patients with peritoneal metastasis (PM). Patients with PM who underwent CRS and HIPEC between 2007 and 2020 were analyzed retrospectively. Ileal resection was defined as the resection of the ileum at 100 cm or below. Patients were divided into ileal-resection and non-ileal resection groups. Besides clinico-pathological variables, peritoneal cancer index (PCI), completeness of cytoreduction (CC-0-1-2), (neo)adjuvant chemotherapy, operative time, need for surgical intensive care unit, and usage of blood products were all evaluated. The data of 664 patients was analyzed. Ileal resection was performed in 346(52.1%) patients. The median follow-up period was 27 months. The ileal resection group had significantly lower 3-and 5-year survival rates (55% and 43% vs. 69% and 52, p = .005, respectively). High PCI score (p < .001), more CC-1-2 cytoreductions (p < .001), more anastomoses (p < .001), prolonged operative time (p < .001), more ostomy creation (p = .001), increased morbidity (p < .001), and more infectious complications (p < .001) were all significantly associated with ileal resection. The loss of ileal function has a potential prognostic role in increased post-operative complications and worsened overall survival in patients with PMs.