Ultrasound and Mammographic Features of Ductal Carcinoma in Situ: A Retrospective Review of 70 Ultrasound-Guided Core Needle Biopsy Cases at Ho Chi Minh City Oncology Hospital

Abstract

Background: Ductal carcinoma in situ (DCIS) is a heterogeneous breast malignancy with variable mammographic and sonographic appearances. Although mammography remains the primary modality for detecting DCIS, especially calcified lesions, ultrasound is particularly useful in dense breasts, non-calcified lesions, and biopsy guidance. Upgrade from DCIS diagnosed on core needle biopsy (CNB) to invasive carcinoma on surgical pathology remains clinically important because it may alter surgical planning. Methods: We conducted a retrospective review of ultrasound-guided 14-gauge CNB cases diagnosed as DCIS at the Department of Endoscopy and Ultrasound, Ho Chi Minh City Oncology Hospital, from June 2024 to December 2024. Among 153 CNB-proven DCIS cases, 70 had complete ultrasound, mammography, CNB pathology, and surgical pathology data and were included in the final analysis. Results: Of the 70 included cases, 24 were upgraded to invasive carcinoma on surgical pathology, yielding an upgrade rate of 34.0%. On mammography, the most common presentation was a mass with calcifications (50.0%), followed by non-calcified mass lesions (21.4%) and calcifications alone (14.3%). On ultrasound, 55 lesions (78.6%) appeared as masses and 15 (21.4%) as non-mass lesions. Among upgraded cases, 21 of 24 (87.5%) were mass-forming lesions. Large lesion size (≥20 mm) and multifocality were the most notable features associated with upgrade. Conclusion: DCIS shows diverse mammographic and ultrasound appearances in ultrasound-guided biopsy practice, with a predominance of mass-forming lesions. Lesion size of at least 20 mm and multifocality appear to be useful clues for predicting upgrade from DCIS to invasive carcinoma.