How to select the right patients for focal therapy of prostate cancer?

Just as lumpectomy for breast cancer aims at achieving oncological control with maximal tissue preservation, the concept of focal therapy for prostate cancer has evolved with the aim of controlling disease while preserving urinary and erectile function. Our review aims at describing the evolution of focal therapy in time and the resulting advances in patient selection.

Originally, focal therapy was developed as an alternative to active surveillance for men with low-risk disease and a minimal burden of cancer. However, with improvement of the diagnostic technologies, the entry criteria for this therapeutic approach are broadening. Since its introduction, focal therapy has evolved from ablation of half or three-quarters of the prostate in men with low-risk disease to only selected cancer foci even if they present with Gleason pattern 4. This development has become possible because of a better understanding of the biology of the index lesion(s) and the improvement of biopsy techniques. Candidates were selected at first with conventional transrectal random prostate biopsies. To overcome the sampling bias of standard techniques, a more thorough multicore sampling utilizing transperineal three-dimensional template mapping biopsies was developed. Today, advances in multiparametric MRI allow for detection and targeted biopsies of high-grade and high-volume lesions.

In light of the less stringent selection criteria, enrollment for focal therapy protocols should encourage patient education on the need of possible subsequent cycles of ablation as well as the need for surveillance of the untreated prostatic tissue, as prostate cancer is transformed into a chronic, manageable condition.