RESULTS OF HIFU for Radiation Failure Using Ablatherm Technolgoy

High intensity focused ultrasound has been used as a primary treatment for prostate cancer for 15 years. Recently, the technology has been used also for the treatment for recurrent prostate cancer after radiation treatment. For locally recurrent prostate cancer after radiation treatment in men without metastasis, the largest data on HIFU comes from the French multicenter trial. The initial publication from 290 patients was reported in 2012. This data showed that the 7 year cancer specific rate was 80%. The progression free survival was better in patients who had low and intermediate risk disease. HIFU for patients with recurrence after radiation is called salvage HIFU. Salvage HIFU therapy is administered as whole gland therapy with specific parameters to reduce complications. Recently in 2017 the authors published their results in 418 patients 


Results of HIFU Treatment

The median time between therapy and HIFU was 5.1 years. The mean age of the patient was 68.6 years. Mean PSA before HIFU treatment was 6.8 ng/ml. The mean prostate volume was 20.6cc. Among those treated, 87% had one treatment, 12% had two treatments, and 0.7% of patients had three treatments. Results are given in the following table.

These results show that whole gland salvage HIFU  is feasible with  results similar to that of surgery but with lower side effects. In a detailed analysis of the study results the authors found found that the nadir PSA of less th 0.3 ng/ml was reached in 53% of patients and nadir PSA less than 0.2 ng/ml in 47% of patients. After salvage HIFU 53% of men

 did not need additional treatment. 47% needed Androgen Deprivation Therapy.

The cancer specific and metastatic free survival rate 82% and 81% respectively. The 5 year biochemical disease free rate was 67% ,42% and 22% in men with pre salvage PSA under 4ng/ml, 4-10 mg/ml, and over 10ng/ml. The 5 year biochemical  disease free rate was 59%, 41% and 39% for men with Gleason scores 6,7 and over 7 respectively. These data suggest that salvage HIFU in men with recurrence after radiation should be performed early when PSA is starting to rise but still under 4ng/ml 

The lead author Pr. Sébastien Crouzet commented: "This is the largest series of salvage patients treated with HIFU and followed for data collection. The results are encouraging, and support the use of Ablatherm Robotic HIFU for these patients who are particularly fragile after the failure of their radiation treatment and are limited to minimally invasive treatment options. Patients who require additional treatment after a radiation therapy may benefit from prostate tissue ablation with HIFU."

Compared to results of radical surgery, HIFU treatment after radiation is safer. In the latest results from Crouzet, the cancer specific survival was 82% and metastatic free survival was 81%. This compares to results from post radiation surgery at cancer specific  survival of 64 to 91%. The complication rates, however, are significantly worse with surgery compared to HIFU.

Results of Partial Salvage HIFU for Radiation Recurrence

Between 2009 and 2012, the French investigators  treated 48 men prospectively in 2 centers. Inclusion criteria were positive MRI and biopsy in one lobe diagnosing unilateral cancer after External Beam Radiation (46 men) and after Brachytherapy (seed therapy)(2 men). Mean age was 68.8 ± 6 years, mean pre HIFU PSA was 5.2 ± 5.2 ng/mL and the Gleason score was ≤7: 28, ≥8: 18 and not determined in 2 men. Median follow-up was 16.3 months [range 3-43]. Treatments were performed with Ablatherm® HIFU device.

Results: The mean PSA nadir value was 0.69 ± 0.83 (median: 0.4). Sixteen men had control biopsies because of rising PSA. Local recurrence was found in 4 men in the contralateral lobe, and in 4 men in both lobes. Six patients developed metastases and 2 had rising PSA without local recurrence or proven metastases. 

 Fifteen of these 16 men received salvage treatments (3 re-HIFU, 11 androgen-deprivation, and 1 re-HIFU plus androgen-deprivation). Progression free survival rates  at 12, 18, and 24 months were 83%, 64%, and 52%.

Thirty-six men (75%) were pad-free. Seven  (14.6 %) required 1 pad a day. Severe incontinence occurred in 5 men (10.4%).

The authors concluded that Hemi-salvage HIFU is efficient in patients with unilateral radiation-recurrent prostate cancer.Quality of life was preserved  and cancer control was comparable to whole gland treatment. Hemi-salvage HIFU is possible only for focal relapse identified with MRI and targeted biopsies , early following External Beam Radiation Failure  [5]

Results of this study shows that Salvage Hemi HIFU is safe and feasible even in patients with high Gleason score provided they are detected early and staged carefully with MRI and other tests

Crouzet, et al. BJUI vol 114; 4 October 2014; 5:32