Pooled analysis of the surgical treatment for colorectal cancer liver metastases.

Liver metastases in colorectal cancer patients decreases the expected 5 year survival rates by a factor close to nine. It is generally accepted that resection of liver metastases should be attempted whenever feasible. This manuscript addresses the optimal therapeutic plan regarding timing of resection of synchronous liver metastases and the use of chemotherapy in combination with resection of synchronous metachronous liver metastases. The aim is to pool all published results in order to attribute a level of evidence to outcomes and identify lacking evidence areas. A systematic search of guidelines, reviews, randomised controlled, observational studies and updating a meta-analysis was performed. Data were extracted and analysed. Data failed to demonstrate an effect of timing of surgery or use of chemotherapy on overall survival. Concomitant resection of liver metastases and the primary tumour may result in lower postoperative morbidity. Systemic peri-operative chemotherapy may improve progression free survival compared to surgery alone.