Because of low mortality and morbidity and increasing survival rates the resection of liver metastases of colorectal cancer (CRC) plays an important role in the multimodal management of patients with metastasized CRC. The knowledge of prognostic factors (as for example the FONG-criteria) is crucial in the planning of different treatment options. We here evaluated the outcome after liver resection for CRC metastases and analyzed potential prognostic factors.
Methods: Long-term follow-up was available in 186 patients (32% female, median age 63 years) who underwent primary liver resection for CRC metastases between 1996 and 2006. Initially 57% had colon and 43% rectal cancer. 66% of the primary tumors were lymph node positive. The median time interval between resection of the primary and of liver metastases was 12 (range 0-140) months. For further analyses this interval was classified as < 12 months or ≥ 12 months. Survival analysis was performed by the Kaplan-Meier- and Cox-methods. The FONG-criteria as well as age, gender, blood transfusions and extent of resection were evaluated for potential prognostic influence.
Results: An atypical or segmental resection was performed in 47%, whereas 53% had at least a hemihepatectomy. Free resection margins were achieved in 88%. Five year survival (5-y SV) of all patients after liver resection was 45% (median survival 4.1 years). Univariate risk factors for poorer survival were a positive margin (5-y SV 36% vs 47% with R-0; p=0.001) and size of metastases ≥ 5cm (5-y SV 33% vs 50% < 5cm; p=0.009). A trend to poorer survival was found for patients with node-positive primaries, female gender, more than one metastasis and elevated CEA-levels.In multivariate analysis the resection margin (p=0.003), size of metastases (p=0.002) and gender (p<0.05) were factors independently influencing survival. After classifying patients according to the FONG-criteria (0 to 5 positive) univariate survival analysis showed a clear correlation of survival with this FONG-score (p<0.01): patients with a score of 0 or 1 had a 5-y SV of almost 60%, whereas the five-year survival of patients with a score of four / of five was below 35%/20%.
Conclusions: Prognosis after resection of CRC liver metastases is relatively good especially in the case of small metastases and free resection margins. Identified prognostic factors (e. g. FONG-criteria) should be considered in the planning of multimodal therapy in order to achieve optimal treatment results in the individual patient, possibly even without (primary) resectional therapy in high-risk patients.