Patient selection for focal therapy of localized prostate cancer

Prostate-specific antigen screening has led to a dramatically increased detection of low-grade, small-volume, organ-confined tumors. On the basis of concerns regarding overtreatment of biologically indolent cancers, focal ablative therapy has been introduced as an alternative to radical therapy or active surveillance. Because a critical requirement of focal therapy is appropriate patient selection, we review the pathologic characteristics of localized prostate cancer and methods to identify patients likely to have low-risk disease.

Up to 33% of patients undergoing radical prostatectomy have unilateral, low-grade, organ-confined tumors on final pathology. Standard diagnostic methods such as ultrasound-guided biopsies may not be adequate to reliably identify these patients. Early data on three-dimensional transperineal and transrectal mapping biopsies have suggested an increased ability to precisely localize and characterize low-grade tumors. The addition of multisequence MRI and spectroscopy to standard diagnostic techniques is under study and may eventually further augment disease characterization.

Appropriate selection criteria for focal therapy are evolving, and diagnostic techniques widely vary. Further study of extensive mapping biopsies, imaging techniques, and biomarkers are mandatory to improve the recognition and characterization of patients with biologically indolent lesions and better inform their treatment decision making.