Effect of Ageing on Morphologic and Clinical Predictors of Prostate Cancer Progression

Abstract

Objectives: Autopsy studies show that prostate cancer begins in the 4th and 5th decade of life. We sought to determine if increasing age at the time of diagnosis is related to morphologic and clinical predictors of cancer progression. Materials and Methods: We examined 7 morphologic variables known to impact progression of prostate cancer plus clinical stage and serum PSA in relation to increasing age. 981 untreated men undergoing radical prostatectomy were divided into 5 increasing age groups. Prostate size, which is known to increase with age, was used as a positive control. We compared the median and inter-quartile range for each grouping. Results: Increase in prostate weight was highly significant at all age differences. The % Gleason grade 4/5 cancer and cancer volume showed the most statistically significant changes with ageing, followed by non-organ confined cancer and capsular penetration both of which are highly correlated with cancer volume. Serum PSA was significant at 12, 17, and 22 years of age differences, but may be related more to prostate size than to increasing cancer volume. The presence of positive lymph nodes, seminal vesicle invasion, and palpable cancer were unrelated to increasing age. Conclusions: With the exception of increasing prostate size, % Gleason grade 4/5 cancer and cancer volume are the most significantly related variables to increasing age. Since % Gleason grade 4/5 cancer and cancer volume are also the primary determinants of failure to cure prostate cancer by radical prostatectomy, these age related changes suggest that detection of prostate cancer later in life will be accompanied by increased amounts of high grade cancer and larger tumor volumes. They also explain why, in so many younger men (age 45–60), the largest prostate cancer is often clinically insignificant (< 0.5 cc) at the time of radical prostatectomy.