Editorial Comment on: Focal Treatment for Unilateral Prostate Cancer Using High-Intensity Focal Ultrasound: A Comprehensive Study of Pooled Data by Albisinni et al.

Focal therapy/partial ablation for prostate cancer now garners a lot of attention and controversy. There is intuitive attraction of lower treatment-related morbidity minus the uncertainly of surveillance of a proven malignancy. Critics and skeptics point to the known multifocality nature of prostate cancer, countered by proponents of focal therapy with the “dominant index lesion versus secondary lesions” theory. The authors are to be congratulated for their effort in surveying the evidence on high intensity focused ultrasound (HIFU) as one of the two commonest ablative tools for prostate cancer focal therapy (the other being cryoablation) and also for their diligence in adhering to the PRISMA guidelines for systematic reviews and meta-analyses. ¹ Although the risk of bias was deemed to be low, the level of evidence available for the pooled analysis was generally low (comprising single-institutional nonrandomized case series) and consequently the impact of the end product regrettably suffers.

The authors did highlight the limitations of the pooled analysis with variable inclusion criteria, exclusion criteria, extent of ablation, postprocedural monitoring routine (biochemical, imaging, and histologic), and definitions of urinary and erectile dysfunction.

Salvage treatment-free rate is a meaningful oncologic outcome and was promising from the pooled data, although follow-up was short and has to be interpreted with caution. Emphasizing function outcomes of focal therapy would not have been impactful in terms of advancing focal therapy as a form of treatment for prostate cancer, since patients predictably would and should have “good” functional outcome.

On a broader topic of focal/partial prostate ablation as definitive therapy, there are still several unresolved issues (some of which were highlighted by this pooled analysis): conceptual, technical (i.e., targeting precision/selectivity, reproducibility, and ideal ablative energies), and clinical (i.e., lack of standardization of patient selection, follow-up, and metrics of “success” and “failure”). Limitations aside, this pooled analysis has made a contribution to the literature. However, as rightly pointed out by the authors, higher level evidence from studies addressing the aforementioned unresolved issues is needed to further delineate the role of partial ablation in the management of localized prostate cancer.