Intramammary scar tissue: a mimic of the mammographic appearance of carcinoma.

Scar tissue within the breast parenchyma, when dense and located adjacent to fatty tissue, often appears as a poorly defined, spiculated mass on mammography. Intramammary scars may also appear as areas of architectural distortion or clustered microcalcification, sometimes associated with thickening or retraction of overlying skin. Because of the difficulty in differentiating such benign lesions from carcinoma, false-positive diagnoses of cancer occur. This article illustrates the radiographic spectrum of intramammary scars to familiarize the reader with this entity. Although several differential criteria have been described to help distinguish benign scarring from carcinoma, these features are not totally dependable, resulting in the need for biopsy in most cases and careful clinical and radiographic observation in others.