Radiofrequency ablation in 447 complex unresectable liver tumors: lessons learned.

BACKGROUND: Radiofrequency ablation (RFA) is a promising technique for unresectable hepatic malignancies. We reviewed our RFA experience to identify variables affecting local recurrence.
METHODS: Patients undergoing RFA between 1997 and 2001 were reviewed for demographics, tumor size, pathology, diagnosis, recurrence, procedures, survival, and complications.
RESULTS: The 447 unresectable liver tumors were ablated in 198 procedures. The 153 patients averaged 61.9 years of age and 1.25 RFA procedures per patient. Follow-up averaged 11 months. Serial ablations were performed in 28 patients, 8 of whom are without evidence of disease. Tumors were most commonly carcinomas of colorectal, hepatocellular, breast, and melanoma histologies. Colorectal carcinomas and hepatomas individually recurred more frequently than all other tumor types combined in univariate analyses (P =.009 and P =.008, respectively). Patients with multiple tumors ablated recurred significantly more frequently (P =.001). Size was also significant in univariate and multivariate analyses (P =.0032 and <.0001, respectively). Eighteen patients experienced 36 complications.
CONCLUSIONS: Size has the highest correlation with local recurrence, but multiple tumors and pathology may also predict local recurrence risk. Large, complex lesions can be safely serially ablated, but because of morbidity and recurrence, RFA should not replace resection as the primary treatment of resectable liver tumors.