Study: Prostate Cancer Missed on First Biopsy Likely to Be Smaller

A prostate cancer that is missed on the first biopsy is likely to be at an earlier stage and smaller than a prostate cancer confirmed on the initial test, according to Austrian researchers.

But repeated biopsies that produce "false-negative" result are of no additional prognostic value for the stage of prostate cancers found during a subsequent biopsy, the researchers reported in the journal The Prostate.

The researchers from the University of Innsbruck evaluated 653 patients who had biopsies followed by radical prostatectomies, and compared those diagnosed during their first biopsy to those diagnosed on a second, third, fourth or fifth biopsy.

Gleason scores, pathologic tumor stages, and tumor volumes for the patients whose prostate cancer was missed the first time around "were found to be significantly decreased compared to" those whose cancer was diagnosed during their first biopsy, the researchers reported.

"But from the 2nd to 5th serial biopsy no further decrease in pathologic stage, Gleason score, or tumor volume was observed," the researchers said. "On the contrary, there was a tendency towards higher tumor stages and Gleason scores.

"Of the tumors detected after the second false-negative set of biopsies, almost 70 percent were lesions with Gleason scores of 6 or higher," the researchers added..

"False-negative results at the first needle biopsy are predictive of a lower pathologic stage and grade as well as smaller tumor volumes of prostate cancer diagnosed at repeat sets of biopsies," the researchers concluded. "False-negative results on repeat biopsy, however, have no prognostic significance for the tumor stage of prostate cancers detected at subsequent sets of biopsies."

Other Sources: The Prostate