LAUSR

BACKGROUND Currently, patients with a limited extent of peritoneal metastases from colon and rectal cancer are treated by cytoreductive surgery combined with perioperative chemotherapy performed at experienced centers. OBJECTIVE To study and statistically evaluate features that may impact on survival of 5 years or more. These data are used in the risk/benefit analyses performed by the multidisciplinary team. DESIGN This is a retrospective review of a prospective database. SETTINGS Single institution study at an academic center. PATIENTS All patients who had biopsy-proven colon or rectal peritoneal metastases treated by systemic chemotherapy, complete cytoreductive surgery and perioperative surgery. MAIN OUTCOME MEASURES The primary outcomes measured were the clinical-, histologic- and treatment-related features that had an impact on 5-year survival. RESULTS From 131 patients who had a complete cytoreduction, 35 patients (26.7%) were identified as 5-year survivors. Median survival was 27 months. There were 16 males. Median age was 50.5 with a range of 25 to 80. By univariant analysis, an absence of lymph node involvement at the time of primary colorectal cancer resection (HR 1.899 (1.064, 3.388) p = 0.03), complete or near complete response to neoadjuvant chemotherapy (HR 0.251 (0.092, 0.684) p = 0.007), peritoneal cancer index ≤17 (HR 0.509 (0.329, 0.788) p = 0.002), complete visible resection of disease indicated by completeness of cytoreduction score of 0 (HR 0.412 (0.224, 0.756) p = 0.004) and well-differentiated tumor (HR 0.34 (0.157, 0.737) p = 0.006) were significantly associated with 5 years or greater survival. LIMITATIONS The study was limited by the retrospective nature, by unmeasured confounders, and data from a single institution. CONCLUSIONS The tumor biology as revealed by lymph node status and tumor differentiation plus extent of disease as measured by the response to neoadjuvant chemotherapy, peritoneal cancer index and no visible residual disease indicated a favorable outcome. See Video Abstract at http://links.lww.com/DCR/C62.