Prostate biopsy not the final say

NORTHWESTERN (US) — Nearly 70 percent of men who had a rising prostate-specific antigen (PSA) level, but a normal biopsy, were eventually diagnosed with prostate cancer.

The findings, presented at the annual meeting of the American Urological Association, stress the importance of individual patient trends and repeated follow-ups, even if a biopsy is negative.

“Our findings show an elevated and rising PSA level or velocity should lead a clinician to follow a patient more closely, even if he has a negative biopsy,” says William Catalona, professor of urology at Northwestern University.

“One negative biopsy isn’t the end of the road.”

PSA is a substance whose elevated levels can indicate prostate cancer but can also be caused by prostate inflammation or enlargement or other conditions. Catalona was the first to show in 1991 that a simple blood test measuring PSA levels could be used to detect prostate cancer.

For the study, researchers looked in their database at the history of 97 patients with a rising PSA trend (or velocity) who had a subsequent negative biopsy and found 66 percent of patients were eventually diagnosed with prostate cancer, 20 percent had a benign prostate, 8 percent had protatitis, and 6 percent had premalignant lesions.

“This underscores the importance of using a patient’s individual PSA trend when deciding whether to pursue a prostate biopsy,” says Gregory Auffenberg, a urology resident. “It’s not enough to only look at an individual PSA value when historical data is also available.”

The research was supported in part by the Urological Research Foundation, Prostate SPORE Grant and a Lurie Cancer Center grant.

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