All patients were treated between 2003 and 2015, and all salvage treatments were whole gland, not focal or hemi-gland.
- 37 patients received sLDR-BT
- 61 received sHDR-BT
- 45% received adjuvant androgen deprivation therapy (ADT)
- All patients were screened for distant metastases with a CT or MRI and a bone scan at least
- All patients had biopsy-confirmed cancer in the prostate
After a median follow-up up 31 months:
- 3-year PSA relapse-free survival (RFS) was 60%
- Both therapies were similar
- RFS=39% for those with PSA doubling times (PSADT) less than 1 year vs. 72% for those with PSADTs of a year or more.
- No statistically significant differences in urinary or rectal toxicity between the two therapies: most returned to baseline function.
- sLDR-BT had a higher rate of acute urinary toxicity
- Erectile function was not measured because of high rates of pre-existing impotence and ADT usage
In the Fuller study of salvage SBRT (see this link), bRFS was 82% at 2 years, and ADT was not used. NIH will soon begin recruitment for a clinical trial of salvage SBRT (NCT03253744), which includes detection using the DCFPyL PET/CT - the best of the new generation. Dr. Kollmeier mentioned that MSKCC has treated a few select patients with salvage SBRT as well. They are also looking at using a more tailored approach: adding systemic therapy for higher grade recurrences and focal/hemi-gland treatment for less aggressive cases. MSKCC is on the leading edge of using the new generation of PET/MRI scans which will undoubtedly improve patient selection going forward.