Ductal enhancement on MR imaging of the breast

The purpose of this study was to determine the prevalence and positive predictive value of ductal enhancement among MR imaging-detected breast lesions that had biopsy and to assess the histologic findings associated with ductal enhancement.

Retrospective review was performed of 427 nonpalpable, mammographically occult lesions that had MR imaging-guided needle localization and surgical biopsy. Lesions were reviewed by one radiologist who was unaware of the histologic outcomes and were classified according to a standardized lexicon. MR imaging and histologic findings of ductal enhancing lesions were reviewed.

Ductal enhancement accounted for 88 (21%) of 427 lesions and 88 (59%) of 150 nonmass lesions. Histologic finding in these 88 lesions were ductal carcinoma in situ (DCIS) in 18 (20%); infiltrating carcinoma in five (6%), including three with DCIS; lobular carcinoma in situ (LCIS) in nine (10%); atypical ductal hyperplasia in eight (9%); and benign in 48 (55%). Among the 48 benign lesions, the dominant histologic findings were fibrocystic change (n = 16); ductal hyperplasia (n = 8); fibrosis (n = 8); postbiopsy change (n = 5); benign breast tissue (n = 3); sclerosing adenosis (n = 2); and single cases of fibroadenoma, fibroadenomatoid change, lymph node, mastitis, papilloma, and radial scar. Factors associated with a trend toward a higher frequency of carcinoma included clumped enhancement (p = 0.05) and synchronous ipsilateral cancer (p = 0.07).

Ductal enhancement accounted for 21% of MR imaging-detected lesions that had biopsy and had a positive predictive value of 26%. Differential diagnosis of ductal enhancement includes carcinoma (usually DCIS); atypical ductal hyperplasia; LCIS; and benign findings such as fibrocystic change, ductal hyperplasia, and fibrosis.