High-intensity focused ultrasound (HIFU) followed after one to two weeks by radical retropubic prostatectomy: results of a prospective study.

Background: High-intensity focused ultrasound (HIFU) consists of focused ultrasound waves emitted from a transducer that are capable of inducing tissue damage. Experimental studies have shown clear damage of malignant tissue exposed to HIFU, but knowledge of in vivo effects is limited. We studied the safety and efficacy of HIFU in patients with a T1-2 N0) M0 prostate carcinoma.
Methods: HIFU treatment was performed under general anesthesia with the Ablatherm device (Technomed Medical Systems, Lyon, France), 7-12 days prior to radical prostatectomy. Only the lobe in which carcinoma was confirmed was treated. The radical prostatectomy specimen was examined histopathologically, and the changes were compared with treatment goals.
Results: So far, 9 patients have been treated. On histology, a sharp delineation was noted between areas treated with HIFU and untreated areas. On the dorsal border, however, incomplete destruction of tissue was noted, and in 2 cases a small residual tumor was seen in this region. In all cases complete necrosis was seen in the treated region.
Conclusions: Histology reports of radical prostatectomy specimens of patients operated 7-12 days after HIFU treatment showed marked and complete necrosis in the treated area. Due to incomplete tissue destruction at the dorsal side, however, a small focus of residual vital tumor was found in 2 of 9 patients.