Ultrasound S-detect system can improve diagnostic performance of less experienced radiologists in differentiating breast masses. A retrospective dual-center study.

Objective: To compare the performance of radiologists when assisted by an S-detect system with that of radiologists or an S-detect system alone in diagnosing breast masses on US images in a dual-center setting.

Methods: US images were retrospectively identified 296 breast masses (150 benign, 146 malignant) by investigators at two medical centers. Six radiologists from the two centers independently analyzed the US images and classified each mass into categories 2 to 5. The radiologists then re-reviewed the images with the assistance of the S-detect system. The diagnostic value of radiologists alone, S-detect system alone, and S-detect alone, and radiologists + S-detect were analyzed and compared.

Results: Radiologists had significantly decreased the average false negative rate (FNR) for diagnosing breast masses using S-detect system (- 10.7%) (P < 0.001) and increased the area under the receiver operating characteristic curve (AUC) from 0.743 to 0.788 (P < 0.001). Seventy-seven out of 888 US images from six radiologists in this study were changed positively (from false negative to true positive or from false positive to true negative) with the S-detect, while 39 out of 888 US images were altered negatively.

Conclusion: Radiologists had better performance for the diagnosis of malignant breast masses on US images with an S-detect system than without.

Advances in knowledge: The study used a dual-center design and compared the performance of the radiologists alone, the S-detect alone, and the radiologists combined with the S-detect. The study reported an improvement in sensitivity and AUC particularly for low to intermediate-level radiologists, involved cases and radiologists from two different centers, and compared the diagnostic value of using S-detect system for masses of different sizes.