Ultrasound-guided high-intensity focused ultrasound treatment for needle-track seeding of hepatocellular carcinoma: Preliminary results

Purpose: To evaluate therapeutic efficacy of ultrasound (US)-guided high-intensity focused ultrasound (HIFU) ablation for treatment of needle-track seeding of hepatocellular carcinoma (HCC). Materials and methods: Nine patients with needle-track seeding of HCC were treated as outpatients using US-guided HIFU ablation. The mean size of the lesion was 1.8 cm (range 1.1 to 2.6 cm), two lesions were located on the abdominal wall, seven lesions were located on the chest wall. An acoustic power of 200 to 400 W was used determined by the echo changes after energy exposures, intermittent HIFU exposures of 1 to 2 s were used during treatment. Treatment was considered complete when the entire nodule and a surrounding 0.5 cm margin become hyperechoic on US. The outcome of HIFU ablation was observed by US and contrast-enhanced magnetic resonance imaging during follow up. Results: HIFU ablation was performed smoothly in all patients, the treatment lasted for 6 to 21 min (mean 12 min). No major complications occurred. During a mean follow up of 10.3 months (range 7-15 months), persistent absence of lesion enhancement was seen in eight patients, one patient developed a recurrent lesion near the treated area, which was successfully treated by a repeat HIFU ablation. Conclusions: US-guided HIFU ablation may be an effective treatment for needle-track seeding of HCC.