OBJECTIVE: The purpose of this study was to evaluate the effect of intrahepatic microvascular and lymphatic infiltration on survival in cases of colorectal liver metastases. MATERIALS AND METHODS: Prospectively collected data of 331 patients were analyzed for microvascular invasion (V), lymphatic infiltration (L), and resection margins (R) with respect to overall and disease-free survival. RESULTS: One-, 3-, and 5-year overall survival rates for R0 resected patients were 89%, 64%, and 39%, respectively. The corresponding survival rates for R1 resected patients were 83%, 42%, and 24% (p <0.001). The sole presence of microvascular invasion (V1) or lymphatic infiltration (L1) was not associated with a diminished overall survival (p > 0.05). However, patients with a combination of L1V1 had a significantly worse overall survival of 68%, 20%, and 0% when compared to L0V0 patients. This difference was not influenced by the status of the resection margin. No other parameter investigated was found to be of predictive value. CONCLUSIONS: The presence of combined lymphatic and vascular invasion (L1V1) constitutes a predictor of poor overall and disease-free survival. This subgroup of patients might benefit from adjuvant strategies such as chemotherapeutic treatment.
