Prognosis in patients with synchronous colorectal cancer metastases after complete resection of the primary tumor and the metastases

Background Synchronous metastases are considered a negative prognostic factor in patients with metastatic colorectal cancer (CRC). We investigated the outcomes of stage IV CRC patients undergoing complete gross resection (R0/1) of both the primary tumor and the metastases under the guidance of a multidisciplinary team (MDT). Methods All CRC patients with synchronous metastases were retrieved from a prospective database. Patients treated from 2006 to 2017 who underwent complete resection were analyzed. Various factors, including multiple metastatic sites and complex procedures, were investigated. Univariate and multivariate overall survival (OS) calculations were performed. Results Of 330 consecutive patients with synchronous metastases, 101 (30.6%) achieved an R0/1 status including 12 (11.9%) patients with multiple metastatic sites. Complex procedures were necessary in 45 (44.6%) patients. Five-year OS was 53.0% for the R0/1 patient group. Multivariate analysis could not detect factors associated with prognosis. Conclusions With modern treatment, the prognosis of patients with synchronous CRC metastases can be improved. Decisions made by a MDT offered one-third of patients a potentially curative approach to their stage IV disease. Despite the treatment of a high rate of patients with complex metastases necessitating complex procedures, we achieved a favorable 5-year OS rate.