Prostate Cancer Monitoring Tests May Prompt Patients to Pick More Aggressive Treatment

04/30/03    Portland, Ore.

Younger men more likely to choose aggressive treatment earlier

Some men who are diagnosed with prostate cancer choose to monitor the disease's progress instead of beginning aggressive treatment right away. This is called "watchful waiting."

The relatively new practice of using a prostate cancer monitoring test during this watch-and-wait period may lead men to seek more aggressive treatment earlier, according to a study presented by Oregon Health & Science University scientists on April 30, 2003, during the American Urological Association annual meeting in Chicago.

One of the study's most striking findings is that age is a significant predictor of a patient's willingness to undergo aggressive treatment after first picking watchful waiting as a treatment strategy. Of those men younger than 65, nearly 40 percent chose aggressive therapy within two years of starting watchful waiting that included prostate-specific antigen (PSA) monitoring.

"This is a relatively new phenomenon," said Tomasz M. Beer, M.D., study co-investigator and member of the OHSU Cancer Institute. "In the past, few men who started out on watchful waiting later changed their minds. This study demonstrates that such a change of heart is much more common today. The use of PSA tests in prostate cancer diagnosis and during observation may be one reason for this shift in the outcome of watchful waiting."

In men of all ages who initially chose watchful waiting with PSA monitoring, within 31/2 years almost half received treatment for their cancer, and more than one-fifth chose aggressive treatments. These included removal of the prostate, external radiation and an internal, localized form of radiation called brachytherapy.

PSA is a protein made only by prostate cells. Certain prostate conditions, including prostate cancer, can cause high levels of PSA in the blood. PSA blood levels are monitored to help predict the presence and progression of prostate cancer.

"The outcome of watchful waiting for men with localized prostate cancer has not been fully evaluated since physicians routinely began to use PSA tests to monitor the disease," said Mark Garzotto, M.D., study co-investigator and member of the OHSU Cancer Institute. "The ability to identify patients who seek more aggressive treatments earlier could help physicians reduce prostate cancer progression in these patients."

Beer and Garzotto studied 561 men with prostate cancer. Of those, 192 elected to undergo watchful waiting. Follow-up data were available for 187 patients. Data were collected on all patients diagnosed with prostate cancer at a single institution between January 1993 and December 2000. Factors recorded included: patient age, stage of cancer, Gleason score (extent of differentiation of cancer cells from normal cells), PSA level, prostate gland volume as measured by ultrasound, total number of biopsies obtained, number of biopsies positive for cancer, and initial treatment selections. The outcome of all patients who elected watchful waiting was determined by a review of all medical records and the cancer registry.

Particulars: Tomasz M. Beer, M.D., is an assistant professor of medicine (hematology and medical oncology) in the OHSU School of Medicine, and a member of the OHSU Cancer Institute.

Mark Garzotto, M.D., is an assistant professor of surgery (urology) in the OHSU School of Medicine, director of urologic oncology at the Portland Veterans Affairs Medical Center, and a member of the OHSU Cancer Institute.

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