MORPHOLOGICAL ANALYSIS AND CLASSIFICATION OF LATENT PROSTATE-CANCER USING A 3-DIMENSIONAL COMPUTER ALGORITHM - ANALYSIS OF TUMOR VOLUME, GRADE, TUMOR DOUBLING TIME AND LIFE EXPECTANCY

Purpose: We estimate the potential clinical significance of prostate c ancers found at autopsy provided the individual had lived to the proje cted lifespan based on life expectancy tables. Materials and Methods: We used 3-dimensional computer models of 59 autopsy prostates that con tained clinically undetected carcinoma to determine tumor volumes. Usi ng doubling times of 2, 3, 4 and 6 years, carcinoma volumes at autopsy were extrapolated through patient projected lifespans. The carcinomas were then classified as clinically insignificant or significant accor ding to Mayo Clinic criteria. Results: In 13 patients less than 60 yea rs old, using doubling times of 2, 3, 4 and 6 years, clinically signif icant tumors were identified in 13 (100%), 10 (77%), 7 (54%) and 7 (54 %), respectively. In 46 patients 60 years old or greater significant t umors were identified in 32 (70%), 22 (48%), 21 (46%) and 18 (39%), re spectively. A statistical difference (p <0.0001) was found between the mean tumor volume (0.20 +/- 0.10 cc) of 43 organ confined carcinomas and the mean tumor volume (3.26 +/- 3.58 cc) of 16 extracapsular tumor s. No capsule perforation was found in tumors with Gleason sums of 4 o r less. However, capsule perforation was present in 8 of 31 tumors (25 .8%) with Gleason sums of 5 or 6, and 8 of 11 tumors (72.7%) with Glea son scores of 7 or 8. Conclusions: Prostatic carcinomas that remain cl inically insignificant throughout life are likely to have doubling tim es greater than 4 years. The subset of carcinomas that emerge as clini cally significant are likely to have doubling times less than 3 years. Therefore, an accurate method to measure doubling time at diagnosis c ould, provide an objective indicator to guide clinical management.