[Epidemiologic observations on prostate cancer based on tumor volumes]

Using the SEER Program of the NCI, and the U.S. total mortality rates, we calculated the probability at birth of being diagnosed with prostate cancer within one's lifetime to be 8.8%, and we subtracted the microscopic stage A cancers too small to ever be of clinical significance which gave a final probability of 8%. Prostates were examined in 139 consecutive, unselected cystoprostatectomies from patients with bladder cancers who were unknown to have prostate cancer. Prostate cancer was found in 55 patients (40%); the volume of the largest cancer in each of these 55 prostates was determined by histologic morphometry. We identified the 8% of these 139 cystoprostatectomies with the largest volume of prostate cancer. The largest 11 of the 55 cancers represented 7.9% of the 139 cystoprostatectomies. These cancers ranged in volume from 0.5 cc to 6.1 cc, representing only 20% of all patients with prostate cancer. Thus, if one accepts the strong evidence that cancer progression is proportional to cancer volume, we conclude that prostate cancers larger than 0.5 cc appear to correspond to the 8% of men who will be diagnosed with a clinically significant carcinoma, as derived from SEER data. Conversely, those 80% of prostate cancers under 0.5 cc are probably not destined to reach clinically significant size in view of the very long doubling time of this cancer.