Salvage cryotherapy for recurrent prostate cancer after radiotherapy: variables affecting patient outcome

To determine the long-term disease-specific survival (DSS) and disease-free survival (DFS) rates after salvage cryotherapy for locally recurrent adenocarcinoma of the prostate and to identify pretreatment factors that have an impact on DSS and DFS.

Between July 1992 and January 1995, 131 patients who had received definitive radiation therapy (XRT) underwent salvage cryotherapy for locally recurrent adenocarcinoma of the prostate. Cryotherapy failure was defined as an increasing postcryotherapy prostate-specific antigen (PSA) level of > or = 2 ng/mL above the postcryotherapy nadir, a positive prostate biopsy, or radiographic evidence of metastatic disease. Clinical variables were studied to determine whether there was an association with the DSS and DFS.

The median follow-up was 4.8 years. The 5-year DSS rates were 87% for patients with a precryotherapy Gleason score < or = 8 and 63% for those with Gleason scores of 9 and 10 (P =.012). The 5-year DFS rates were 57% for patients with a precryotherapy PSA level of < or = 10 ng/mL and 23% for those with a PSA level greater than 10 ng/mL (P =.0004). The 5-year DSS rates for patients with a pre-XRT clinical stage of T1 to T2 and those with a clinical stage of T3 to T4 were 94% and 72%, respectively (P =.0041). The 5-year DFS rates for these groups were 90% and 69%, respectively (P =.0057).

Androgen-independent local recurrences, Gleason score, and pre-XRT clinical stage were important factors that had an impact on DSS and DFS. The subset of patients cured by salvage cryotherapy seems to be small, and patient selection is important.