High-Intensity Focused Ultrasound as Salvage Therapy for Patients With Recurrent Prostate Cancer After Radiotherapy

Purpose: To evaluate the oncologic outcomes and postoperative complications of high-intensity focused ultrasound (HIFU) as a salvage therapy after external-beam radiotherapy (EBRT) failure in patients with prostate cancer. Materials and Methods: Between February 2002 and August 2010, we retrospectively reviewed the medical records of all patients who underwent salvage HIFU for transrectal ultrasound-guided, biopsy-proven locally recurred prostate cancer after EBRT failure (by ASTRO definition: prostate-specific antigen [PSA] failure after three consecutive PSA increases after a nadir, with the date of failure as the point halfway between the nadir date and the first increase or any increase great enough to provoke initiation of therapy). All patients underwent prostate magnetic resonance imaging and bone scintigraphy and had no evidence of distant metastasis. Biochemical recurrence (BCR) was defined according to the Stuttgart definition (PSA nadir plus 1.2 ng/mL). Results: A total of 13 patients with a median age of 68 years (range, 60-76 years) were included. The median pre-EBRT PSA was 21.12 ng/mL, the pre-HIFU PSA was 4.63 ng/mL, and the period of salvage HIFU after EBRT was 32.7 months. The median follow-up after salvage HIFU was 44.5 months. The overall BCR-free rate was 53.8%. In the univariate analysis, predictive factors for BCR after salvage HIFU were higher pre-EBRT PSA (p=0.037), pre-HIFU PSA (p=0.015), and short time to nadir (p=0.036). In the multivariate analysis, there were no significant predictive factors for BCR. The complication rate requiring intervention was 38.5%. Conclusions: Salvage HIFU for prostate cancer provides effective oncologic outcomes for local recurrence after EBRT failure. However, salvage HIFU had a relatively high rate of complications.