Evaluation of Patients for Salvage HIFU
Evaluation of Men with Radiation Recurrence prior to Salvage HIFU
For men to be considered for salvage HIFU treatment they need to meet the following requirements:
Documented Biochemical failure/Elevated, Rising PSA (Astro,Phoenix criteria)
Post-radiation biopsy that is positive for cancer.
Metastatic evaluation that shows no evidence of cancer in a bone scan, multiparametric pelvic and prostate MRI and
F18Choline PET Scan
The contraindications for salvage HIFU include:
Rectal or Anal stenosis, and a rectal wall thickness that is more than 6 millimeters on transrectal ultrasound. Rectal wall that is more than 6 millimeters will cause heat to dissipate into the rectal wall and increase chances of rectal injury.
Salvage HIFU Treatment Protocol
The post-radiation therapy HIFU protocol for use with the Ablatherm device includes a 4 second pulse for treatment, a 6 second waiting period, and 90% of the 40 watt acoustic power. This is based on the fact that prior to 2002 higher power and 6 second pulse of energy with a 4 second delay caused more morbidity. The main concern for morbidity is the rectal wall, which has some ischemia secondary to radiation and develops thickness and scar tissue which can absorb heat during the HIFU process.
There are additional considerations when patients with post-radiation recurrence are treated with HIFU.
Patients should have an evaluation with cystoscopy and if they have urethral or bladder neck strictures they should be incised. Patients who have a median lobe should have the median lobe resected.
In the French experience, the largest to date, patient follow-up included clinical and biochemical evaluations every 3 months for the first year and every 6 months thereafter.
The follow-up protocol for biopsies after salvage HIFU is still under evaluation.
It is reasonable to do biopsies at 6 months after the treatment and at any time if a PSA starts rising. If there is a rise in PSA, patients should have a complete evaluation including workup for metastatic disease.
A second HIFU treatment was offered in the French series when only local recurrence was identified