High intensity focused ultrasound for treating residual liver cancer after radiotherapy: primary clinical observation

Abstract

Objective To investigate the safety and effect of high intensity focused ultrasound ablation(HIFU) on residual liver cancer in patients after radiotherapy. Methods Twenty liver cancer patients with twenty five residual tumors after three-dimensional conformal radiotherapy or stereotactic radiotherapy received HIFU ablation. Liver function and periphery blood cell counts were performed before HIFU and at 1 week after HIFU in all patients. Enhanced MRI and α-fetoprotein (AFP) level were performed before HIFU and at 2 weeks after HIFU to evaluate the effect of HIFU ablation. The survival of all patients was assessed by the Kaplan-Meier method. Results The mean follow-up time was (12.6 ± 8.0)months. The median survival time and 1-year survival rate were 22 months and 87.5% respectively. No skin burns were observed in all patients. As compared with before HIFU,there were no significant differences in the levels of albumin,alanine transarninase, aspartate transarninase, total bilirubin, direct bilirubin, blood red cell counts,blood white cell counts and blood platelet counts at 1 week after HIFU (paired t test, P =0. 156,0. 356,0. 203,0.659,0. 531,0. 519,0. 310,0. 346, respectively). Significant difference in AFP level of 9 patients with AFP＞20 μg/L was observed before HIFU and 2 weeks after HIFU (paired t test, P =0.030). Among 25 residual liver tumors,sixteen with complete ablation and six with ablation volume of ≥80% were observed by enhanced MRI at 2 weeks after HIFU. Conclusions HIFU may be a safe and effective new method to ablate residual liver cancer after three-dimensional conformal radiotherapy or stereotactic radiotherapy. Key words: High intensity focused ultrasound; Liver neoplasms; Radiotherapy,computer-assisted