Utility of T-weighted MRI texture analysis in assessment of peripheral zone prostate cancer aggressiveness: a single-arm, multicenter study.

T-weighted (TW) MRI provides high spatial resolution and tissue-specific contrast, but it is predominantly used for qualitative evaluation of prostate anatomy and anomalies. This retrospective multicenter study evaluated the potential of TW image-derived textural features for quantitative assessment of peripheral zone prostate cancer (PCa) aggressiveness. A standardized preoperative multiparametric MRI was performed on 87 PCa patients across 6 institutions. TW intensity and apparent diffusion coefficient (ADC) histogram, and TW textural features were computed from tumor volumes annotated based on whole-mount histology. Spearman correlations were used to evaluate association between textural features and PCa grade groups (i.e. 1-5). Feature utility in differentiating and classifying low-(grade group 1) vs. intermediate/high-(grade group ≥ 2) aggressive cancers was evaluated using Mann-Whitney U-tests, and a support vector machine classifier employing "hold-one-institution-out" cross-validation scheme, respectively. Textural features indicating image homogeneity and disorder/complexity correlated significantly (p < 0.05) with PCa grade groups. In the intermediate/high-aggressive cancers, textural homogeneity and disorder/complexity were significantly lower and higher, respectively, compared to the low-aggressive cancers. The mean classification accuracy across the centers was highest for the combined ADC and TW intensity-textural features (84%) compared to ADC histogram (75%), TW histogram (72%), TW textural (72%) features alone or TW histogram and texture (77%), TW and ADC histogram (79%) combined. Texture analysis of TW images provides quantitative information or features that are associated with peripheral zone PCa aggressiveness and can augment their classification.