A recently published article in Urology Times claims that salvage high-intensity focused ultrasound (HIFU) appears to be an effective treatment option for locally recurrent prostate cancer after primary external beam radiation therapy (EBRT) failure. The study, which this article reported on, used data from analyses of 6-year oncologic outcomes show.

When the researchers did a subgroup analysis of the data they concluded that the HIFU must be performed quickly after the radiation failure. This need for quick action was more pronounced for men who had been previously treated with hormone deprivation therapy (ADT).

The study’s first author Sebastien Crouzet, MD, Assistant Professor of Urology and Transplantation at the Edouard Herriot Hospital, Lyon, France reported the results at the AUA annual meeting in Atlanta. She said that, “In our series, there were a number of men who presented for salvage treatment with a very high PSA, and we think many of those cases may be explained by referral delay.”

“She went on to say, “This is important because our outcomes data suggest that if HIFU is to be considered as definitive local salvage therapy with curative intent, early detection of radiation failure and prompt treatment are important.”

Biochemical survival and complications following salvage HIFU using the Ablatherm device (EDAP TMS, Lyon, France) were analyzed in a cohort of 982 men using data from a secured online database (@-Registry). The population was comprised of 411 men who had received ADT and 571 who had no prior hormone treatment. At the time of HIFU, which was about 5.1 years after the end of EBRT, the men had a mean age of about 69 years, mean ± standard deviation PSA of 14.6 ng/mL ± 42.6 ng/mL, and median Gleason sum of 7.

The median PSA nadir after HIFU was 0.2 ng/mL and was reached at a mean of 13.4 weeks. There was little difference in the PSA nadir between men who had received ADT compared with those who had no hormone treatment (0.22 vs. 0.2 ng/mL).
During a mean follow-up of 2 ± 2.2 years after HIFU (range, 0 to 15 years), 35.7% of men received salvage treatment, but the salvage rate was only 28.5% for the men who had not received hormones versus 45.7% for those who had received ADT. With biochemical failure defined using Phoenix criteria (PSA nadir +2), the Kaplan-Meier estimated biochemical disease-free survival (BDFS) rates at 4, 5, and 6 years in the overall population were 57%, 51%, and 46%, respectively. Patients underwent biopsy at 3 months after HIFU and then if PSA rose above 1.0 ng/mL during follow-up.

Further analyses of BDFS rates were conducted with patients divided according to pre-HIFU ADT use and PSA level (<4.0 ng/mL, 4.0-10.0 ng/mL, and >10.0 ng/mL), and the results showed a dramatic improvement in outcome with early salvage treatment, Dr. Crouzet said.

Among men who had no ADT, 6-year BDFS rates for those in the lowest, middle, and highest PSA tiers were 67%, 57%, and 40%, respectively, whereas for the men who had received ADT, the rates were 46%, 36%, and 25%, respectively.

Salvage HIFU is a good alternative for men who have failed radiation therapy because it has a good safety profile. Side effects like incontinence occurred in approximately 23% of men and was grade I in 9.8%, grade II in 8.8%, and grade III in 4.2%. Men also experienced other complications. At a rate >5% men experienced urethral stenosis (12%); urinary retention (9%); urethrorectal fistula occurred in 1.2% of men and pubis osteitis in 0.7%.

Bottom Line- HIFU is a good alternative choice for men who have experienced a local prostate cancer recurrence after having failed external beam radiation therapy as a primary treatment. However, it is vital that the HIFU treatment commence quickly after the failure, especially for men who have also had hormone therapy.

Joel T. Nowak, M.A., M.S.W.