KLK3 and cancer: Indeed, use of prostate mpMRI with targeted biopsy has improved detection of clinically significant, high-grade cancer (ie, cancer of GG 2 or greater) in men with tumors visible on mpMRI.7 While these data support prebiopsy mpMRI in patients requiring biopsy, the use of negative findings on mpMRI to rule out high-grade cancers in men with elevated PSA levels is not well supported.