Impact of resection for primary colorectal cancer on outcomes in patients with synchronous colorectal liver metastases.

<bold>Purpose: </bold>This study was designed to evaluate the impact of resection for primary colorectal cancer on oncologic outcomes in patients with synchronous colorectal liver metastases.<bold>Methods: </bold>A retrospective analysis was performed on 91 consecutive patients with synchronous colorectal liver metastases who underwent resection of the primary colorectal cancer between December 1999 and December 2007. Of the 91 patients, 54 (59.3%) also underwent complete (R0) resection for liver metastases, and 84 (92.3%) received postoperative chemotherapy. The oncologic outcomes and prognostic factors were analyzed.<bold>Results: </bold>Operative mortality was 1.1%, and morbidity was 37.4%. The 3- and 5-year overall survival rates were 44.5% and 26.8%, respectively. A multivariate analysis revealed that residual disease after surgery (non-R0 resection; p = 0.003), lymph node metastasis of the primary tumor (p = 0.015), and no postoperative chemotherapy (p = 0.001) were independent prognostic factors for poor survival. Independent predictors of an inability to achieve a complete resection were the presence of three or more liver metastases and the presence of extrahepatic disease at exploration. Significant differences in survival existed among the three risk stratification groups (no-, low-, and high-risk groups; p < 0.001).<bold>Conclusions: </bold>The inability to safely render the liver and colon microscopically free of disease should cause a surgeon to reconsider synchronous colectomy and hepatectomy. A multidisciplinary approach that combines both complete resection of synchronous colorectal liver metastases and postoperative chemotherapy may achieve improved survival in patients with synchronous colorectal liver metastases. [ABSTRACT FROM AUTHOR]