Radiofrequency ablation of metastatic liver masses: recurrence patterns and prognostic factors based on radiologic features.

Abstract

BACKGROUND/AIMS: To investigate the therapeutic result of RFA and the factors predicting recurrence after RFA in patients with hepatic metastases.

METHODOLOGY: We reviewed 33 patients who had hepatic metastases and underwent curative RFA. Statistical analysis of the determinants of tumor recurrence was done by sex, age, site and differentiation of the primary cancer, lesion size, location within the liver, ablative margin and presence of vessels contiguous to the mass and time from the initial liver metastasis to RFA.

RESULTS: Marginal tumor recurrence was seen at the ablation margin in 13 (25%) of 52 lesions. Lesions with an ablative margin of 5mm or more had longer marginal recurrence-free interval compared to lesions with an ablative margin of less than 5mm. The patients with primary colorectal cancer had a significantly longer distant recurrence-free interval compared to patients with non-colorectal neoplasms.

CONCLUSIONS: Percutaneous RFA is an effective alternative modality for the treatment of hepatic metastases from various primary cancers and has a relatively low recurrence rate. The presence of an ablative margin was a significant prognostic factor for marginal tumor recurrence. In addition, distant metastasis, a new hepatic lesion or extrahepatic was significantly influenced by the site of the primary cancer.