Impact of Time of Occurrence of Liver Metastases (Synchronous vs. Metachronous) on Early Postoperative Outcome and Long-Term Survival of Colorectal Cancer Patients

Background: Today, liver resection represents the only curative treatment option for patients with resectable colorectal liver metastases. Large studies could show that liver surgery can be performed safely in specialised centres, but most of those studies did not differentiate between resection of synchronous and metachronous metastases. The aim of this study was to evaluate the impact of the time of the occurrence of colorectal liver metastases on the early postoperative course as well as the long-term survival. Patients and Methods: Two groups of 30 patients each who underwent liver surgery due to synchronous or metachronous colorectal liver metastases at our centre between 2000 and 2010 were included in a matched-pairs analysis. Early postoperative course as well as long-term survival were assessed and compared between both groups. Matching criteria included: age, sex, number of metastases and size of largest metastasis. Results: Postoperative morbidity for the entire study cohort was 23.3% with a mortality of 0%. No significant difference could be shown between synchronous and metachronous metastases with regard to incidence and severity of postoperative complications (20 vs. 26.7%, p = 0.54). The median survival of the synchronous group was 38.9 months (95% CI 26.4-51.6) compared to 47.9 months (95% CI 21.4-74.4%) in the metachronous group, but no significant difference could be detected in the univariate analysis (p = 0.425). Conclusion: According to the present results, liver surgery can be performed safely in a specialised centre. The time of occurrence of the metastases (synchronous vs. metachronous) does not seem to have any impact on the early postoperative course as well as on the long-term survival in patients undergoing curative resection of colorectal liver metastases. However, larger studies appear necessary to confirm the results of the present study.