Significance of the craniocaudal distribution of cancer in radical prostatectomy specimens

Objectives: To examine the differences in the distribution of prostate cancer (PCa) in the craniocaudal dimension and their potential significance. Methods: We studied 1253 patients with clinically localized PCa treated with radical prostatectomy (RP) from 1983 to 2000. We analyzed the clinicopathological features according to the craniocaudal distribution (apex, mid, base) of the largest cancer focus. Results: Of these patients, 456 (36%) had the largest cancer focus in the apex, 728 (58%) in the mid, and 69 (6%) in the base. The cancers in the apex were less invasive than those in the mid or base, as evidenced by the lower frequency of extracapsular extension (27% vs 43%, 52%, respectively) and/or seminal vesicle involvement (5% vs 13%, 20%, respectively). The frequency of the largest cancer focus in the apex has increased significantly over time, from 26% before 1995 to 46% after 1995 (P < 0.001). Serum prostate specific antigen non-progression rate at 10 years for patients with a cancer at the apex was 83%, which was better than 76% and 77% of patients with a cancer at the mid or base (P = 0.029, P = 0.14, respectively). Conclusion: The cancers dominant at the apex are increasing over time and represent half of the patients treated by RP in recent years. These cancers tend to be less aggressive compared to those in the mid or base of the prostate. This knowledge may be useful in understanding the biology of and maximizing the detection of PCa.