Although PSA is used to screen for prostate cancer, high PSA results can occur for many reasons other than prostate cancer, including an enlarged prostate gland, prostate infection, recent sexual activity, or rigorous exercise. In fact, three out of four men with an elevated PSA do not have prostate cancer. Often, an elevated PSA result will lead to additional follow-up, like biomarker testing, to help determine whether prostate cancer is present.