Automated breast ultrasound (ABUS) versus handheld ultrasound (HHUS) for the preoperative assessment of tumor size in invasive breast cancer

Purpose: Accurate preoperative assessment of tumor size (T parameter) is crucial for surgical planning in breast cancer. This study aimed to compare the diagnostic performance of automated breast ultrasound (ABUS) and conventional handheld ultrasound (HHUS) in evaluating tumor size, using histopathology as the reference standard. Methods: Between September 2025 and March 2026, 43 patients with 46 invasive breast carcinoma lesions underwent preoperative evaluation with both HHUS and ABUS. Tumor diameters were measured by two experienced radiologists. Measurements obtained with each imaging modality were compared with histological findings. Statistical analysis included analysis of variance (ANOVA), paired Student’s t-tests, and inter-observer agreement using Cohen’s kappa coefficient. Results: Mean tumor diameters were 12.82 mm for ABUS, 12.50 mm for HHUS, and 12.74 mm for histology. No statistically significant differences were observed between ABUS and HHUS measurements (p = 0.07), nor between either imaging modality and histology (ABUS vs. histology: p = 0.15; HHUS vs. histology: p = 0.86). Inter-observer agreement was excellent (κ = 0.88). Measurements obtained with ABUS showed a closer overlap with histological findings. Conclusion: Both ABUS and HHUS provide accurate preoperative assessment of tumor size in invasive breast cancer. However, ABUS demonstrates advantages in reproducibility, operator independence, and three-dimensional visualization, supporting its role as a valuable tool for surgical planning.