Resection of liver metastases in colorectal cancer--competitive analysis of treatment results in synchronous versus metachronous metastases.

One hundred and twenty-two patients underwent liver resection for metastases of colorectal cancer within 8 years. Seventy-four of them were treated for metachronous metastases detected in a median of 18 months after resection of the primary tumor. In another 48 patients the metastases were resected at the same time as the primary cancer. Both groups were analysed for disease-free and overall survival, and for peri-operative morbidity. However, neither the type of hepatic resection nor peri-operative morbidity showed relevant differences in the groups, except for the metachronous group, the only group in which operative mortality occurred (6.7%). Survival was not significantly different, being 32 months in the metachronous and 24 months in the synchronous groups (P = 0.051). However, disease-free survival showed significant differences; no patient in the synchronous group experienced a recurrence-free interval of more than 3 years. The median time interval until diagnosis of a recurrence was 10 months after resection of metachronous metastases, but only 6 months in the synchronous group (P = 0.018). The pattern of recurrence showed a much higher proportion of patients with disseminated disease in the synchronous group (95% vs 42%). Therefore, liver resection in synchronous colorectal metastases should be handled very restrictively and adjuvant treatment strategies considered in the future.