T1-Weighted Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) to Distinguish Between Concurrent Cholesterol Granuloma and Invasive Ductal Carcinoma of the Breast: A Case Report.

BACKGROUND Cholesterol granuloma is a benign condition that can be misdiagnosed as breast cancer on mammographic and ultrasound imaging. A case of concomitant cholesterol granuloma with invasive ductal carcinoma of the left breast was imaged with ultrasound elastography and magnetic resonance imaging (MRI) methods, including T1-weighted dynamic contrast-enhanced MRI (DCE-MRI), before biopsy and histopathology. CASE REPORT A 52-year-old woman, with a previous history of intraduct papillomas in both breasts, underwent six-monthly follow-up breast imaging. The most recent breast mammogram showed a progressively enlarging oval mass in the upper inner quadrant (UIQ) of the left breast, and an adjacent irregular mass with microcalcifications. Virtual Touch IQ (VTIQ) shear wave elastography was used with ultrasound of the breast lesions. T1-weighted fat saturation (T1WFS) MRI, T2-weighted short-tau inversion recovery (STIR) MRI, and T1-weighted DCE-MRI were used to image the left breast. T1-weighted DCE-MRI showed that the oval lesion had a high T1-weighted signal and mild progressive enhancement, with a Type I (benign) time-signal intensity curve; the second, irregular, mass showed rapid, intense enhancement with a washout pattern or Type III (malignant) time-signal intensity curve. Histopathology confirmed that the oval mass was a cholesterol granuloma, and the irregular mass was an invasive ductal carcinoma. CONCLUSIONS A case of concomitant cholesterol granuloma with invasive ductal carcinoma of the left breast, showed that ultrasound with shear wave elastography and T1-weighted DCE-MRI could distinguish between cholesterol granuloma and invasive ductal carcinoma.