Surveillance after prostate focal therapy

Long-term outcomes from large cohorts are not yet available upon which to base recommended follow-up protocols after prostate focal therapy. This is an updated summary of a 2015 SIU-ICUD review of the best available current evidence and expert consensus on guidelines for surveillance after prostate focal therapy.

We performed a systematic search of the PubMed, Cochrane and Embase databases to identify studies where primary prostate focal therapy was performed to treat prostate cancer.

Multiparametric magnetic resonance imaging (mpMRI) should be performed at 3-6 months, 12-24 months and at 5 years after focal therapy. Targeted biopsy of the treated zone should be performed at 3-6 months and fusion biopsy of any suspicious lesion seen on mpMRI. Additionally, a systematic biopsy should be performed at 12-24 months and again at 5 years. In histological diagnosis, characteristic changes of each treatment modality should be noted and in indeterminate situations various immunohistochemical molecular markers can be helpful. Small volume 3 + 3 (Prognostic grade group [PGG] 1) or very small volume (< 0.2 cc or < 7 mm diameter) 3 + 4 (PGG 2) are acceptable in the treated zone at longitudinal follow-up. Significant volumes of 3 + 4 (PGG 2) or more within the treated zone should be treated. Any clinically significant cancer subsequently arising within the non-treated zone should be treated and handled in the same way as any de novo prostate cancer. Patients should be counseled regarding whole-gland and focal approaches to treating these new foci where appropriate. One or two well-delineated foci of significant cancer can be ablated to keep the patient in the 'active surveillance pool'. More extensive disease should be treated with traditional whole-gland techniques.

Focal therapy remains a nascent field largely comprising single center cohorts with little long-term data. Our current post-focal therapy surveillance consensus recommendations represent the synthesis of the best available evidence as well as expert opinion. Further work is necessary to define the most oncologically safe and cost-effective way of following patients after focal therapy.