Salvage cryotherapy as second-line treatment after first-line radiation therapy
Posted Feb 10 2011 12:00am
We really have no idea what the “best” way is to treat men with progressive disease after first-line radiation therapy. Salvage surgery is a difficult surgical procedure and patients can have serious incontinence problems in addition to the near certainty of impotence. Early hormone therapy is an obvious choice, but again comes with near certainty of impotence (as well as the known side effects and risks for cardiovascular and metabolic problems). High-intensity focused ultrasound is a relatively new option, but data are very limited indeed. … And then there is salvage cryotherapy.
Williams et al. have have conducted a retrospective analysis of available data from patients who received salvage cryotherapy at their institution (between 1995 and 2004) for biopsy-proven, recurrent prostate cancer after the failure of first-line radiation therapy. It should immediately be noted that data from as long ago as 1995 reflect some of the very early patients to receive “modern” salvage cryotherapy as a follow-up to radiation therapy.
All patients received two freeze-thaw cycles of transperineal cryotherapy, performed under transrectal ultrasound guidance by a single surgeon.
The results of this analysis are as follows:
A total of 187 men received salvage cryotherapy over 9 years.
176/187 patient records were available for follow-up (follow-up rate: 94 percent).
The average (mean) follow-up was 7.46 years (range, 1 to 14 years).
52/176 patients were followed for > 10 years.
10-year disease-free survival was 39 percent.
Risk factors for recurrence were the patient’s pre-salvage PSA level, pre-radiation, and the patient’s pre-salvage Gleason score.
A PSA nadir >1.0 ng/dl was highly predictive of early recurrence.
The authors summarize these data by stating that salvage cryotherapy offers an “acceptable” 10-year rate of biochemical progression-free survival; that the pre-salvage therapy PSA level and Gleason score are the best predictors of potential for disease recurrence; and that a nadir PSA level of > 1 ng/dl after salvage cryotherapy was a certain indicator of poor prognosis and disease recurrence in this set of patients.
The one thing that is not clear to The “New” Prostate Cancer InfoLink from this study is whether the units of the PSA level given are correct. A PSA level of > 1.0 ng/dl (one nanogram per deciliter) is equivalent to > 0.01 ng/ml. We suspect that when the authors wrote “> 1.0 ng/dl,” they may have meant to write “> 1.0 μg/dl” (one microgram per deciliter), which is precisely equivalent to > 1.0 ng/ml (one nanogram per milliliter).