Assessment of the role of ultrasound in the differentiation of radial scars and stellate carcinomas of the breast.

Radial scars are benign lesions of the breast which cannot be reliably distinguished from carcinoma by their mammographic appearances alone [1,2]. The present wisdom is that all such lesions should be biopsied [2]. We report a retrospective study carried out to assess whether there are any ultrasound imaging features that may be useful in differentiating radial scars from carcinoma and so reduce the need for excision biopsy. Over a period of 44 months between 1988 and 1992, 530 patients underwent surgery for abnormalities detected by routine mammographic screening. Of the 191 benign lesions excised, 24 were radial scars. Ultrasound images of 21 radial scars were mixed with an equal number of images of histologically proven carcinomas that had similar mammographic appearances. These images were reviewed 'blind' by a single radiologist. We were unable to find any ultrasound appearances sufficiently specific to radial scars to allow confident exclusion of malignancy. We therefore endorse the current practice of biopsying all mammographically detected stellate lesions.