Microvascular infiltration has limited clinical value for treatment and prognosis in hepatocellular carcinoma.

Background: Microvascular infiltration (MVI) is considered a necessary step in the metastatic evolution of hepatocellular carcinoma (HCC), but its prognostic value after liver resection (LR) is uncertain. We studied the clinical value of MVI compared to the Milan criteria in a consecutive series of patients submitted to radical LR.
Methods: A total of 441 patients were retrospectively evaluated. MVI and the Milan criteria were analyzed and compared as prognostic factors for overall and disease-free survival (DFS).
Results: MVI was present in 189 patients (42.8 %). Grading, satellitosis, size of cancer, and alfa fetoprotein value were significantly related to MVI, which was present in 34.3 and 53.2 % of Milan+ and Milan- patients, respectively (p = 0.00001). Both MVI and the Milan criteria were associated with a lower overall and DFS, but only the Milan criteria were associated with the rate of early recurrence and the feasibility of a curative treatment of the recurrence. The application of MVI parameters to patients classified by the Milan criteria further selects the outcome in Milan+ patients (5-year survival rate of 54.1 and 67.9 %, respectively, in the presence or absence of MVI) but not in Milan- patients.
Conclusions: MVI is related to survival after LR for HCC, but the clinical value of this information is limited. In Milan+ patients, the absence of MVI selects the cases with better prognosis. In the presence of a liver recurrence, the Milan criteria related to the primary HCC show a better prognostic accuracy and have clinical relevance in the decision-making process.