Cytoreductive surgery with or without hyperthermic intraperitoneal chemotherapy for small bowel neuroendocrine tumors with peritoneal metastasis

Background: Up to 20% of patients with small-bowel neuroendocrine tumors (SB-NETs) may present with peritoneal carcinomatosis (PM). Surgical cytoreduction (CRS) has been proposed as an adequate management as it confers a survival benefit in selected patients. The addition of hyperthermic intraperitoneal chemotherapy (HIPEC) to CRS in this context may be an option but data on its added benefits is lacking. Methods: A search was performed in the prospective multicenter international collaborative database of the Peritoneal Surface Oncology Group International (PSOGI) and BIG-RENAPE working groups, and patients who underwent a surgical treatment (CRS or CRS with HIPEC) for a SB-NET with PM were identified and compared. Results: Between 2002 and 2016, a total of 67 patients were identified as having a CRS for SB-NET, with 36 receiving HIPEC during surgery. Median postoperative follow-up was 34 months. The peritoneal cancer index (PCI) and the completeness of cytoreduction score (CCR-score) were higher in the CRS-HIPEC group. More grade III-IV complications occurred in this group as assessed by the National Cancer Institute Common Terminology Criteria for Adverse Events Version 4.0. Despite a tendency toward a better progression/recurrence-free survival in patients receiving HIPEC, no significant differences were noted between the CRS and CRS-HIPEC groups in terms of postoperative recurrence. Conclusions: HIPEC does not seem to provide additional benefits in terms of postoperative evolution and survival in patients with SB-NET undergoing CRS. It is associated with higher morbidity. It may possibly lead to an improved recurrence-free survival, but further reports are required to confirm this assumption.