We read with interest this recent article from Illing et al.[1] suggesting standardisation of the technique for HIFU in prostate cancer. The authors compared two different treatment approaches; an algorithm-based approach (group 1) and a visually directed approach (group 2), and hypothesized the potential technical advantage of the visually directed approach. They cited Uchida et al.[2], who reported a mean PSA nadir of 1.38 ng/mL using the same device, and claimed an advantage in terms of statistically significant lower PSA levels. By contrast, we would like to highlight the study by Blana et al.[3], who reported a median PSA level at 3 months of 0.07 ng/mL, in a similar patient group and with the algorithm-based approach using the Ablatherm® device. Similarly, a recent paper from Poissonnier et al.[4] showed comparable results with this technique.

It is unclear from the study of Illing et al. whether the two groups were truly randomized or whether group 1 were the first patients treated, in which case the results might in part reflect training and experience. Despite there being no difference in catheter-free rates or infective episodes between the groups, the visually directed HIFU group certainly had a higher intervention rate, with flexible cystoscopy due to irritative and obstructive complications. It is also our view that the subjective nature of the ‘Uchida’ changes make them potentially difficult to grade. We therefore question the conclusion of this paper, that a visually directed approach is better than an algorithm-based approach.