Focal therapy for prostate cancer: Making the punishment fit the crime

Focal therapy is recently gaining popularity as an intermediate option between active surveillance and whole-gland treatment for localized prostate cancer.

This comprehensive review aims to present the different focal therapy technologies available to date while tackling the rationale for focal treatment, its indications, principles and outcomes of each technique.

A comprehensive review of the PubMed, Embase, and Web of Science was done. Keywords used for research were: "prostate cancer"; "focal therapy"; "focal treatment"; "High-Intensity Focal Ultrasound"; "cryotherapy"; "photodynamic therapy"; "focal laser ablation"; "irreversible electroporation"; "focal brachytherapy" and "gold nanoparticle directed therapy". Accepted languages were English and French.

Choosing the best candidate for focal therapy is crucial (localized small to medium sized Gleason≤7 lesions). Focal high-intensity focal ultrasound has shown excellent survival rates at 5 years, while maintaining good functional outcomes (urinary continence and erectile function). Focal cryotherapy, one of the oldest focal treatments for prostate cancer, has shown good oncologic outcomes, with good continence rates and fair erectile function rates. Focal laser ablation seems a safe and feasible technique, with promising results. Irreversible electroporation has demonstrated good survival outcomes with no biochemical recurrence or disease relapse in the preliminary studies. Focal brachytherapy has a good toxicity profile, a good biochemical outcome, and gives a sustained quality of life. Finally, gold nanoparticle directed therapy is safe and is being studied in current trials.

While proven to be safe in terms of continence and sexual aspects, the challenge remains to better assess oncological outcomes of these techniques in randomized longer follow-up studies.