EFFECTS OF AGE, SEX STEROIDS, AND FAMILY RELATIONSHIPS ON VOLUMES OF PROSTATE ZONES IN MEN WITH AND WITHOUT PROSTATE-CANCER

Benign prostatic hyperplasia (BPH) and prostate cancer commonly occur together. This suggests that common familial, hormonal, and environmen tal factors contribute to their development. In men at risk for the de velopment of prostate cancer (at 40 men in 19 families) and aged-match ed unrelated controls (n = 46), we have determined whether familial fa ctors, age, and blood hormone concentrations are related to the transi tion zone (TZ), peripheral zone (PZ), or total volume of the prostate measured by transrectal ultrasound (TRUS). We determined that the infl uences of age, prostate cancer (n = 15), and familial status did not s ignificantly affect the relationships reported. Therefore, data from a ll groups were combined for this study. TZ correlated positively with age (P = 0.003) after controlling for family status, but total prostat e volume correlated insignificantly with age (P = 0.08). In addition, the ratio of TZ to PZ volumes also correlated significantly with age i n the control group (r = 0.27, P = 0.014). Both TZ and PZ volumes corr elated highly(r = 0.91, P < 0.0001, n = 86) with total volume. In addi tion, total volume correlated significantly (r = 0.71, P < 0.001) with the ratio of the TZ/PZ volumes, which also correlated significantly w ith each other (r = 0.61, P < 0.0001, n = 86). In contrast to the incr ease of TZ volume related to total prostate volume, PZ volume declined compared with total volume. Prostate volumes up to 50 mi are predomin ated by the PZ and above 50 mi by the TZ, which may compress and shrin k the PZ. Both TZ and total prostate volume correlated positively with serum estrone concentrations (P = 0.04 and P = 0.003, respectively). These results suggest that the risk of prostate cancer does not contri bute to generalized overgrowth of the prostate, including the TZ. Howe ver, estrogens and age strongly influence TZ but not PZ volume. Both P Z and TZ volumes rise together until the prostate exceeds 50 mi, when the growth of the TZ appears to exceed the PZ and then to compress it. (C) 1995 Wiley-Liss, Inc.