Micro-Ultrasound Sagittal Length to Predict Clinically Significant Prostate Cancer in Lesions Visible on Both MRI and Micro-Ultrasound (Dual-Image Visible Lesions)
Francis Nguyen, Dan Luca, Kevin Walsh, Ailene Corona, William Chen, Seryn Ma, Ankush Sachdeva, Qi Miao, Steve Raman, Anthony Sisk, Kyunghyun Sung, Wayne G. BrisbanePurpose:
Dual-imaging visible prostate lesions (Prostate Imaging Reporting and Data System [PI-RADS] ≥ 4 and Prostate Risk Identification Using Micro-Ultrasound [PRI-MUS] ≥ 4) demonstrate high sensitivity for Grade Group (GG) ≥ 2 cancer but limited positive predictive value (PPV). We evaluated whether micro-ultrasound sagittal lesion length improves the prediction of GG ≥ 2 cancer in this high-risk population.
Materials and Methods:
We retrospectively analyzed 273 MRI/micro-ultrasound concordant lesions from men undergoing targeted prostate biopsy. All lesions were PI-RADS ≥ 4 and PRI-MUS ≥ 4. Maximal sagittal lesion length was measured on micro-ultrasound. PPV for GG ≥ 2 disease was calculated across 0.1 cm length thresholds. Logistic regression quantified the association between sagittal length and GG ≥ 2 cancer. GG distributions were compared across 0.5 cm length bins using χ 2 analysis.
Results:
Baseline PPV for dual-imaging visible lesions was 72.6%. A sagittal length threshold ≥ 2.1 cm yielded a PPV of 91.6%. All lesions ≥ 3.0 cm harbored GG ≥ 2 cancer (n = 9). On univariate analysis, each 1 cm increase in sagittal length was associated with an 8.7% increase in the odds of GG ≥ 2 disease (
Conclusions:
In dual-imaging visible lesions, micro-ultrasound sagittal length has potential to provide incremental risk stratification for GG ≥ 2 prostate cancer. A threshold of approximately 2 cm confers > 90% PPV, offering a practical, real-time metric to refine risk assessment during targeted biopsy.