May 13, 1997
Media Contact: Marc Kusinitz
Researchers at Johns Hopkins and other institutions have refined a chart that helps physicians determine how advanced a prostate cancer may be and guides treatment decisions.
The charts, called "nomograms," are a more accurate version of those developed by Hopkins researchers, according to Alan Partin, M.D., Ph.D., assistant professor of urology at the Johns Hopkins Brady Urological Institute.
The nomograms will be published in the May 14 issue of the Journal of the American Medical Association.
The nomograms combine in one chart information from three tests for prostate cancer: the clinical stage, Gleason score and PSA level. The clinical stage of cancer is found by digital rectal exam, in which the physician physically evaluates the prostate gland. The Gleason score is obtained by studying samples of the organ and its cells. The PSA level is the level of prostate specific antigen, a protein released by the gland. Higher levels of PSA suggest the gland is enlarging, perhaps due to cancer.
The newly revised nomograms were developed by using data from 4,133 men who underwent prostate cancer surgery for cancer at Johns Hopkins, Baylor University and the University of Michigan.
Current testing suggests about 60 percent of men with newly diagnosed prostate cancer have disease confined to that organ, according to Partin. "Unfortunately, after these men undergo surgery and their prostate is studied, more than half have cancer that has already spread from the prostate and may not be curable by surgery alone. The use of nomograms should improve our ability to identify those men who can best be cured by surgery alone."
"Counseling patients and helping them choose which treatment they prefer is difficult," says Partin, "because the decision depends in part on what level of risk the patient is comfortable with. A man may want surgery to remove a prostate with early cancer and risk impotence or lack of urinary control. Or he may want to avoid surgery and be treated with radiation or chemotherapy at an early stage of cancer. These nomograms are an important addition to that decision-making process."
In 1996, there were more than 317,000 new cases of prostate cancer diagnosed and more than 41,000 prostate cancer deaths.
Other authors of the study include Eric N. P. Subong and Patrick C. Walsh (Johns Hopkins), Kirk J. Wojno and Joseph E. Oesterling (University of Michigan), Michael W. Kattan and Peter T. Scardino (Baylor University, Houston, Texas), and J.D. Pearson (Merck Research Laboratories, Rahway, N.J.).