CHARACTERIZATION OF PROSTATE SIZE, PSA AND ENDOCRINE PROFILES IN PATIENTS WITH SPINAL-CORD INJURIES

Aims of this study: From cross-sectional and longitudinal population b ased studies as well as from autopsy studies it is well documented tha t total prostate volume increases with advancing age. However, it is n ot well known (1) which factors are ultimately responsible for this gr owth phenomenon; or (2) at what time in a persons life the growth tend s to occur. At present at least a permissive role for testicular andro gens is assumed to be involved in growth regulation. Other factors suc h as growth factors, epithelial-mesenchymal interaction, and the role of intact neural pathways are still poorly understood. We aimed to stu dy a group of men with spinal cord injuries to determine whether the p attern of prostate enlargement would be different in men with partiall y or completely interrupted innervation of the pelvis and the prostate gland. Materials and methods: Forty-three men from the Spinal Cord In jury (SCI) Service at the VA North Texas Health Care System ranging in age from 27-73 y (mean 51 y) were recruited to participate in this st udy. Time since SCI ranged from 2-47 (mean 19 y). All patients underwe nt standardized questionnaire, physical examination, transrectal ultra sonography (TRUS) measurements of total and transition zone volume of the prostate, serum PSA, testosterone (T), dihydrotestosterone (DHT), FSH and LH measurements, some had TRUS guided biopsies taken. Results: By all the measured criteria there were no abnormalities regarding th e pituitary-gonadal axis observed in these men. Testicular volume, ser um T, DHT and LH were within normal ranges, and when the patients were stratified by age, no differences were identified. There was an age r elated increase in FSH which has been described in neurologically inta ct men. Serum PSA increased slightly with advancing age. While total ( TPV) and transition zone (TZV) prostate volume increased with age, the groupwise differences by decades of life were not significant. Moreov er, when compared to a group of community dwelling men without known p rostatic diseases and a clinic cohort of men with BPH, TPV was substan tially lower for each decade of life except for men in their 40s, whil e TZV was substantially lower for men in their 60s. Conclusions: We ob served normal age related changes regarding serum PSA and serum FSH wi thout significant changes in other hormonal parameters. All parameters behaved consistent with changes described in neurologically intact po pulations. However, we did not observe the typical increase in TPV and TZV of the prostate as seen in population, autopsy and clinic patient studies. This interesting finding indicates that factors other than a n intact pituitary-gonadal axis and male steroid hormones may be respo nsible for the normal age related growth of the prostate. Further stud ies in larger cohorts are needed to corroborate our findings.