Capromab Pendetide Scanning Has a Potential Role in Optimizing Patient Selection for Salvage Cryosurgical Ablation of the Prostate

Abstract

To evaluate an algorithm using Capromab pendetide scanning (CPS) and prostate biopsy to select appropriate patients with biochemical recurrence (BCR) after radiation therapy (RT) for salvage cryosurgical ablation of the prostate (CSAP) and to avoid premature androgen deprivation therapy (ADT); and to estimate the local salvage success rate for patients with high-risk clinical features. Sixty-nine patients underwent a history, physical, CPS, and prostate biopsy. Patients with a negative or prostate-only positive signal and a positive biopsy were offered CSAP. Success was defined as a postsalvage nadir PSA of ≤ 0.4 ng/mL. Patients who failed were followed to establish when they required ADT. The results were compared with the putative results of applying clinical parameters alone. Patients were considered high-risk if they had any of the following characteristics: stage T3B-T4, Gleason ≥ 4 + 3, PSADT ≤ 10 months or presalvage PSA > 10 ng/mL. Twelve patients (6 with metastatic signal and 6 with negative biopsy) were excluded. Fifty-seven patients underwent CSAP. Overall 67% were successfully treated. Pre-salvage PSA was significantly associated with success (P = .013). Using clinical risk alone, only 14 patients achieved success compared with 38 using our algorithm. Most of the patients (75%) avoided ADT over a period of 21 months. Using our algorithm with CPS and prostate biopsy enabled us to spare some low-risk patients the undue morbidity of local salvage procedures that are likely to fail, while offering selected high-risk patients the opportunity for cure, avoiding premature ADT. Low presalvage PSA seems to be correlated with successful outcomes.