HIFU is becoming increasing popular as a primary alternative treatment for men diagnosed with prostate cancer that is confined in the gland. Commonly used in Europe and in Mexico, HIFU is also being evaluated in a clinical trials in the United States. As with all primary prostate cancer treatments, it too has a failure rate. Recently there has been a study using salvage radiotherapy after HIFU to evaluate its feasibility, tolerance, and oncologic control
From March 1995 to May 2004, 45 patients presenting with local failure after HIFU underwent salvage radiotherapy alone (n = 32) or combined with hormonal therapy (n = 13). Both the tolerance for the radiation therapy was evaluated by using the Radiation Therapy Oncology Group score for urinary and digestive side effects, and incontinence was evaluated using the Ingelman Sundberg score. Subjects were asked to answer a questionnaire, which was then tabulated by the researchers.
For the 32 patients who underwent radiotherapy alone, the oncologic early results were evaluated by the disease-free survival rate, defined as no biochemical progression and no need for androgen suppression therapy.
The median and mean follow-up were 40 and 46 months, respectively, for the whole series. No additional digestive or urinary toxicity developed with salvage radiotherapy after HIFU. The data from 32 patients were evaluated, with a median follow-up of 37 months after radiotherapy. The 5-year disease-free survival rate was 64% for the 32 patients evaluated. The 5-year disease-free survival rate reached 80% for patients treated for positive biopsy findings and was 44% for those with isolated biochemical failure.
Results from this small study demonstrated that salvage radiotherapy after HIFU for local recurrence is feasible and well tolerated. Additionally it does not seem to pose any additional toxicity. The early oncologic results are encouraging even when isolated local recurrence is experienced.
HIFU seems to offer great potential for the treatment of prostate cancer and radiation offers another shot at the cancer in case of a recurrence. The sample size in this study was very small and we need to see a longer time line to better evaluate the long term efficacy of both HIFU and follow-up radiation in instances of HIFU failure.
For information on the current clinical trials of HIFU go to:
HIFU, is a therapy that destroys tissue with rapid heat elevation, which essentially “cooks” the tissue. Ultrasound energy, or sound waves, are focused at a specific location and at that “focal point” the temperature raises to 90 degrees Celsius in a matter of seconds causing the targeted tissue to be ablated. HIFU does not use any radiation and may be repeated if needed.
Urology. 2008 May 23. Epub ahead of print.
Joel T Nowak MA, MSW