Histological presence of viable prostatic glands on routine biopsy following cryosurgical ablation of the prostate

Purpose: Cryosurgical ablation of the prostate has recently received much attention as a therapeutic alternative for the treatment of localized prostatic adenocarcinoma. Biopsies after treatment reveal a variety of dysplastic changes as well as unaltered prostatic glandular epithelial elements. Prostate specific antigen (PSA) remains undetectable in the majority of men. However, in some PSA increases without demonstrable local recurrence. Materials and Methods: A total of 383 patients underwent 447 procedures between June 1990 and January 1994. Of 358 biopsies performed at our institution, 317 (2,075 cores) were available for review. Each core was examined for unaltered prostatic glandular epithelial elements and then scored for the percentage of epithelial glandular involvement according to a scale of: 0-no, 0.5-less than 10%, 1-10 to 25%, 2-25 to 50%, 3-50 to 75% and 4-76 to 100% unaltered prostatic glandular epithelial elements. Results: Of 317 biopsies 158 (49.8%) contained no unaltered prostatic glandular epithelial elements, while 185 (58.3%) and 206 (65%) had 1 core containing 10% and 10 to 25%, respectively, of such elements. Of 262 cases (82.6%) with a mean of 10% unaltered prostatic glandular epithelial elements per core 22 (8.4%) were positive for residual carcinoma. Among 55 cases with more normal epithelium per core 24 (43.6%) were positive for residual carcinoma. Patients with a positive biopsy had a median PSA of 2.02 ng./ml. (average gland/core score 0.54). Median PSA for men with negative biopsies was 0.2 ng./ml. (gland/core score 0.124). Conclusions: Cryosurgical ablation of the prostate has the ability to ablate prostatic tissue completely, thus rendering it free of glandular elements as determined by biopsy. Increasing PSA can indicate residual glandular elements. Increases in unaltered prostatic glandular epithelial elements with time are not paralleled by increased rates of local disease recurrence. Undetectable serum PSA has a low risk of residual unaltered prostatic glandular epithelial elements and localized carcinoma. Results as measured by unaltered prostatic glandular epithelial elements and PSA improve with the surgical experience.