Transrectal high-intensity focused ultrasound using the Ablatherm device in the treatment of localized prostate carcinoma

Abstract

Objectives. High-intensity focused ultrasound (HIFU) consists of focused ultrasound waves emitted from a transducer that are capable of inducing tissue damage. The histologic effects and clinical outcome of the HIFU treatment were studied in two different groups of men with prostate carcinoma. Methods. The HIFU treatment was performed under regional or general anesthesia with the Ablatherm device. In one group, HIFU was performed 7 to 12 days before radical prostatectomy, and meticulous histopathologic examination of the radical prostatectomy specimens was performed. The second group consisted of patients with localized prostate carcinoma for whom radical prostatectomy was not an option and who received HIFU treatment alone. Results. In 14 patients treated with HIFU before radical prostatectomy, complete necrosis was seen in the treated region in all cases. On the dorsal border, however, incomplete destruction of tissue was noted, and in 4 cases a small vital tumor focus was seen. In the second group, of those patients in whom the entire prostate was treated, a negative biopsy result and a prostate-specific antigen (PSA) level less than 4 ng/mL was obtained in 60% and a PSA nadir less than 0.5 ng/mL in 55% of patients. Conclusions. HIFU treatment results in the two groups clearly demonstrate the potential of this modality in the treatment of localized prostate carcinoma. This study showed that extensive coagulative necrosis can be obtained in the treated areas; however, exact targeting is crucial and a prerequisite for extended clinical application of HIFU.