Sonographic Correlations With Histological Grade and Biomarker Profiles in Breast Invasive Ductal Carcinoma

Invasive ductal carcinoma (IDC), the most common breast cancer subtype, exhibits significant heterogeneity, limiting traditional prognostic markers. Molecular profiles improve precision, but imaging features may also reflect tumor biology.

This study evaluates the predictive potential and clinical applicability of ultrasound features for determining tumor grade and molecular profiles in IDC.

A blinded radiologist retrospectively analyzed 109 IDC cases using the American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS) classification, evaluating ultrasound features such as lesion shape, margins, orientation, echo pattern, calcifications, vascularity, and lymph node involvement. Tumors were graded histologically (Scarff-Bloom-Richardson system) as low (grades 1 and 2) or high (grade 3). Immunohistochemistry determined estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki-67 status. ER and PR positivity were defined as > 10% nuclear staining, HER2 graded on a 0-3+ scale, and Ki-67 positivity as ≥ 10% staining. Statistical analyses, including logistic and linear regression, examined correlations between ultrasound features and histological/molecular profiles. Among 109 women (mean age 48.4 ± 12.5 years), the mean tumor length and width were 21.83 ± 11.22 mm and 15.3 ± 6.97 mm, respectively. Histopathological grading revealed that grade 2 tumors were predominant (51%), while grade 1 and grade 3 tumors were observed in 25% and 24% of cases, respectively. ER and PR positivity were observed in 76.4% and 67.6% of cases, respectively. High-grade tumors were significantly associated with ER and PR negativity (p-value < 0.05). Ultrasound features associated with high-grade tumors included larger tumor length (p-value = 0.029). ER positive tumors had smaller axillary lymph nodes (p-value < 0.05). Likewise, PR positive tumors exhibited smaller suspicious axillary lymph nodes compared to PR negative cases (p-value = 0.004).

Sonographic features may correlate with histological grades and hormone receptor statuses in breast IDC, suggesting that ultrasound could aid in predictive assessment.