OBJECTIVE: To review the different types of radial scar/complex sclerosing lesion (RS/CSL) seen on clinical, mammography, and ultrasound examinations. The histopathology findings and the association of RS/CSL with atypical hyperplasia and malignancy are discussed. MATERIALS AND METHODS: We performed a retrospective study of patients from the files of the "Centro de Diagnóstico por Imagem and Hospital Santa Rita" - Vitória, ES, Brazil, of the period between October, 1993 and December, 2001. A total of 926 non-palpable lesions of 901 patients submitted to excision biopsy after pre-surgical localization were studied. Fifty-seven patients had pathology proven RS/CSL diagnosis. RESULTS: The age of the patients ranged from 31 to 84 years (average 49 years). There were palpable lesions in 10 patients (17.9%). The mammographic signs that suggested the need of biopsy were divided into three groups: architectural distortion (48 patients; 85.7%), stellate nodules (4 patients; 7.1%), and asymmetric densities (4 patients; 7.1%). Microcalcifications were detected by mammography alone in 14 patients (25%) and in the surgical specimen in 20 (35.7%) patients. Among 51 patients submitted to ultrasound, 17 had irregular hypoechoic areas with posterior acoustic shadowing. Of the 57 patients with RS/CSL, 42 had ductal hyperplasia, 9 had atypical ductal proliferation and 6 had infiltrative carcinoma. CONCLUSION: Differential diagnosis of RS/CSL from carcinomas can not be made using imaging methods and excision biopsy is mandatory.

Keywords: Radial scar, Breast cancer, Breast fibrocystic disease, Mammography, Breast ultrasound