Focal prostate therapy: will we ever know the best energy?

Abstract

The study in the current issue of the BJUI by Durand et al. 1 from Montsouris shows that focal cryotherapy can eradicate cancer in >80% of rebiopsied patients, with acceptably low complication rates. They have applied Clavien–Dindo scoring for complications, which is welcome. When even some of the giants of laparoscopic and robot-assisted prostatectomy are looking at minimally invasive focal therapies, we can see that the concept is here to stay, although it is clearly not suitable for all patients. A procedure carried out in an ambulatory setting, with no major surgery or radiation exposure sounds attractive, particularly to patients. But the problem in analysing such papers is the variability in both patient selection and follow-up, as well as the lack of standardization of techniques and follow-up protocols. There is debate and confusion over the place of MRI diagnosis as well as the biopsy technique used to select patients, with standard biopsies missing significant contralateral tumours in too many patients 2. So selection of patients for these novel therapies remains a problem. As mentioned by the authors, even the largest registry of patients undergoing cryotherapy, the Cryo On-Line Database (COLD) 3, has great variations in entry and follow-up stringency; follow-up for novel prostate cancer treatments needs to be rationalized and standardized. The common call at the end of a comment such as this is for a large randomized controlled trial (RCT), but a recent multicentre study of salvage prostate cryotherapy in the UK failed because of slow recruitment and issues with study support from local funding bodies. A recent UK-based feasibility study to consider randomizing surgery vs brachytherapy concluded that this would not be viable 4. In addition, we previously showed that the quality of most RCTs in surgery is so low that the results are of dubious reliability 5. Equipment manufacturing companies rarely have the resources or the inclination to properly fund and run large multicentre RCTs. So what should we tell our patients? It is clear that in correctly selected patients, focal prostate cancer therapy can be a safe and effective option in the medium term. We are unlikely to see direct comparative studies, so agreement is needed on how we select patients for inclusion. Agreement and commitment to standardized follow-up is also needed. This should not be too hard to obtain. Surgeons offering focal therapies should agree with other groups to standardize protocols, and to collect and share honest data. If we did only this, it would allow better future data from focal therapy studies to be available to our patients than we have been able to give for other curative options until very recently. None declared.