Mid-term results demonstrate salvage high-intensity focused ultrasound (HIFU) as an effective and acceptably morbid salvage treatment option for locally radiorecurrent prostate cancer

Abstract

Background: Local occurrence of prostate cancer (PCa) after external beam radiation (EBRT) may benefit from definitive local therapy.

Objective: To evaluate the safety and efficacy of salvage high-intensity focal ultrasound (HIFU) in local PCa recurrence after EBRT and to determine prognostic factors for optimal patient selection.

Design, setting, and participants: Between 1995 and 2006, patients with a local PCa recurrence after EBRT were retrospectively included.

Intervention: All patients received salvage HIFU with the Ablatherm device.

Measurements: Prognostic factors (pre-EBRT risk group, androgen-deprivation [AD] use, pre-HIFU prostate-specific antigen [PSA], Gleason score and positive biopsy percentage) were studied in univariate and multivariate analyses. Progression was defined as positive biopsy and/or last PSA > nadir + 2 ng/ml and/or adjuvant therapy introduction. All complications were recorded.

Results and limitations: Some 194 HIFU sessions for 167 patients were performed. Local cancer control was achieved with negative biopsy results in 122 (73%) patients. The median PSA nadir was 0.19 ng/ml. The mean follow-up period was 18.1 mo (range: 3-121 mo). Seventy-four patients required no hormone therapy. The actuarial 5-yr overall survival rate was 84%. The actuarial 3-yr progression-free survival rate was significantly lower in three circumstances: (1) worsening of the pre-EBRT stage with 53%, 42%, and 25% for low-, intermediate-, and high-risk patients, respectively, (2) increase in the pre-HIFU PSA, and (3) use of AD during PCa management. In multivariate analyses, the risk ratio for intermediate- and high-risk patients were 1.32 and 1.96, respectively. The risk ratio was 2.8 if patients had received AD. No rectal complications were observed. Urinary incontinence accounted for 49.5% of the urinary sphincter implantations required in 11% of patients. This is a retrospective study in which the role of the PSA doubling time and the time until recurrence was not evaluated.

Conclusions: Salvage HIFU is a curative treatment option for local relapse after EBRT with acceptable morbidity. Careful patient selection is imperative depending upon the aforementioned prognostic factors.