Objective: Our objective was to evaluate the effect of sonography-guided percutaneous microwave ablation of high-grade dysplastic nodules in the cirrhotic liver.
Materials and methods: From July 1997 to May 2003, 49 histologically proven high-grade dysplastic nodules in 30 patients with liver cirrhosis were treated by microwave ablation. Three patients had concomitant small hepatocellular carcinomas (D < 3.0 cm), whereas another three had undergone liver segmentectomy for hepatocellular carcinoma 1 year earlier. The mean size of the nodules was 1.8 cm (range, 0.9-4.6 cm). Sixty-eight insertions with 78 applications were administered to the 49 nodules.
Results: The follow-up period was 12-82 months (mean, 45.1 +/- 19.0 months). Five patients died during this study: three from advanced hepatocellular carcinoma, one from bleeding in the upper gastrointestinal tract, and another from cerebral hemorrhage. All nodules showed decreased density on unenhanced CT and no enhancement on contrast-enhanced CT after microwave ablation. Posttreatment biopsy performed in 16 patients with 18 nodules 1-3 months after microwave ablation showed no evidence of viable tissue but replacement by fibrotic tissue in all nodules.
Conclusion: Percutaneous microwave ablation as a minimally invasive therapy is effective for ablating high-grade dysplastic nodules, thus preventing their potential malignant transformation, which may improve survival. The preliminary data warrant further prospective, randomized studies.