Prostatic growth rate determined from MRI data: Age-related longitudinal changes

Men with prostatic enlargement are at highest risk of developing symptomati c lower urinary tract symptoms (LUTS) and related outcomes, such as acute u rinary retention. The study of prostatic growth rate can identify the age r ange at which prostate growth peaks. Evaluation of the natural course of pr ostate growth requires repeated intraindividual volume measurements at time intervals sufficient to document growth. Our objective was to examine age- stratified prostate growth rates from men taking part in a longitudinal stu dy of aging using magnetic resonance imaging (MRI) of the prostate. Sixty-f our men (ages 30-71 years) enrolled in the Baltimore Longitudinal Study of Aging (BLSA) who had T2 pelvic MRIs taken approximately every 2 years were studied. Men were age stratified into four groups: <45, 45-55, 56-65, and > 65 years old. Whole prostate and central gland (anatomically referred to as the transition zone) volumes were determined from the MRI images by a semi -automated image analysis program. Peripheral gland volumes were calculated as the difference between whole prostate and central gland volumes. Growth rates (cc per year) were calculated as change in volume divided by the tim e interval. On the basis of measurements from the T2 images (n = 128), we o bserved a linear trend between prostate volume and age. The overall prostat e growth rate was 2.36 +/- 3.52 cc per year. Age-stratified growth rates re vealed that prostate growth increased with age, peaked at 4.15 +/- 4.98 cc/ year for the 56-65-year-old age group and then declined rapidly for the old er-aged men. The central gland growth rates followed a trend similar to tot al prostate volume. These data suggest that there is an age-related increas e in prostate growth rate that peaks in men ages 56-55 and then declines. i dentification of this trend in prostate growth may aid physicians in target ing men for early diagnosis of LUTS and for possible early intervention. Fu ture studies with a larger sample size are necessary to substantiate these findings.