Low PSA and Prostate Cancer
Low PSA and Prostate Cancer: Study ResultsImportantly, the study also found that only 2.3 percent of men in the study with PSA levels of 4 ng/ml or less had high-grade cancers. For men with a PSA of 2 or lower, the chance of having a high-grade cancer was even lower -- 1.4 percent.
Grade was measured by Gleason score, a system that ranks tumors from 2 to 10 based on their appearance under the microscope. High-grade tumors -- Gleason scores of 7 to 10 -- often grow more quickly and may be more likely to spread than lower-grade tumors.
Gleason scores of the highest grades -- 8 or 9 -- were found in only seven participants, or 0.2 percent of men in the study. Most of the men with prostate cancer, 349 of them (78 percent), had Gleason scores of 5 or 6.
Low PSA and Prostate Cancer: ConclusionsAt this point, there needs to be better methods to distinguish the harmless, slow-growing cancers from the more aggressive ones. If more biopsies are performed at lower PSA levels, more cancers will be found and treated.
But some men would undergo prostate cancer treatment, and the risks associated with it, for tumors that would never have been clinically significant. Treatment for prostate cancer can sometimes lead to impotence, urinary incontinence, and other problems, causing a substantial health burden for men.
In other words, lowering the PSA threshold for proceeding to prostate biopsy would increase the risks of overdiagnosing and overtreating clinically unimportant prostate cancer.