Purpose: We assessed how well preoperative serum prostate specific antigen (PSA) reflects the largest cancer in consecutive untreated radical prostatectomies during the last 20 years at Stanford University.
Materials and methods: A total of 1,317 consecutive radical prostatectomies were divided into 4, 5-year periods between August 1983 and July 2003, and examined sequentially in 3 mm step sections by 1 pathologist. The largest cancer and 5 other histological variables in each prostate were measured. Preoperative clinical stages were tabulated for each 5-year period. Means, Pearson correlation coefficients, % change and multiple regression were used to compare selected variables.
Results: Most parameters decreased linearly during the 20 years, including palpable nodules on digital rectal examination from 91% to 17%, mean age from 64 to 59 years, mean serum PSA from 25 to 8 ng/ml, and index (largest) cancer volume from 5.3 to 2.4 cc. Percent Gleason grade 4/5 of the largest cancer averaged 27% to 35% and prostate weight 44 to 53 gm. Contrasting August 1983 to December 1988 with January 1999 to July 2003, 6 histological cancer parameters had statistically significant relationships to serum PSA in the first period. In the last 5 years serum PSA was related only to prostate size.
Conclusions: Serum PSA was related to prostate cancer 20 years ago. In the last 5 years serum PSA has only been related to benign prostatic hyperplasia. There is an urgent need for serum markers that reflect the size and grade of this ubiquitous cancer.