Correlation of Ultrasonography Features of Breast Masses with Hormone Receptor Status and Molecular Subtypes of Breast Cancer

Objectives: The purpose of the study is to inquire the possibility of predicting tumour subtypes of breast cancer based on imaging features of breast lesions on ultrasonography.

Methodology: This cross-sectional study was conducted on 55 patients who were referred to the department of Radiodiagnosis of K.S.Hegde Medical Academy who were diagnosed or suspected to have breast cancer. USG features of breast lesions were characterised based on BIRADS lexicon. After histopathological confirmation and Immunohistochemistry (IHC) analysis, lesions were classified into molecular subtypes. Association of the USG features of lesions with molecular subtypes and hormone receptor status were assessed statistically.

Results: Majority of the tumours belonged to Luminal B (LB) subtype followed by Triple negative breast cancer (TNBC), human epidermal growth factor receptor 2/neu (Her 2 Neu) enriched and Luminal A (LA) subtypes in descending order. Majority of LA subtype showed non parallel orientation, posterior acoustic shadowing, calcifications and vascularity. Most of the Her 2 neu enriched subtype showed non-parallel orientation, lesion calcifications and none showed posterior acoustic features. Non parallel orientation and increased vascularity were also observed in TNBC lesions. Posterior acoustic enhancement was seen in only TNBC subtype lesion. Lesions showing posterior acoustic shadowing were associated more with Hormone receptor (HR) positive status.

Conclusion: Though most of the subtypes of malignant breast tumours showed similar features on USG , the combination of features would help in predicting the molecular subtype to some extent.