Computer-aided ultrasonography (HistoScanning): a novel technology for locating and characterizing prostate cancer

To assess the extent to which prostate HistoScanning (PHS), a new ultrasound-based technology that uses computer-aided analysis to quantify tissue disorganization induced by malignant processes, can identify and characterize foci of prostate cancer compared with step-sectioned radical prostatectomy (RP) specimens.

Between September 2004 and February 2006, 29 men had PHS before their scheduled RP. A three-dimensional ultrasound raw-data file was acquired, and PHS analysed regions of interest (ROI) corresponding to tissue volumes of approximately 0.04 mL. In 13 men the histology was examined on sections of the whole-mount prostate onto which a grid of 5 x 5 mm squares was applied. On a test set of 14 of the 29 patients, PHS analysis was used before knowing the histology results (blinded data), to predict the maximum tumour diameter, focality, laterality and extraprostatic extension (EPE).

Identification and characterization by PHS of the index tumour in the 14 patients in the test set correlated closely (r = 0.95, P < 0.001) with the reference test. The concordance in the attribution of multifocality (present/absent), unilateral/bilateral disease between PHS and histology was 100%. EPE as determined by PHS was attributed to all three pT3a pathological specimens in the blinded paired data. In the same set of data, EPE was attributed to one prostate cancer that on pathological inspection was deemed to be organ-confined (pT2b).

PHS has the potential to identify and characterize prostate cancer foci noninvasively. The precision appears to be sufficient to suggest that PHS might be useful as a triage test for men deemed to be at risk of prostate cancer and who wish to avoid prostate biopsy.