Radial scars are getting more and more common since the implementation of mammography as a diagnostic tool in screening women for breast cancer. At the Karolinska Hospital, 18,987 asymptomatic women, between the ages of 50 and 69, were screened for breast cancer by means of mammography during the period August 1989 to May 1991. A total of 735 (3.87%) women were recalled for additional views after initial mammograms and 463 (2.44%) were assessed with the help of cytology. In all 175 (0.92%) women were selected for surgery and 146 (0.77%) had histologically verified cancers. The remaining 29 (0.15%) had non-malignant lesions of which 11 (0.06%) were radial scars. All radial scars were diagnosed on mammograms and later confirmed with histology. The radiologic characteristics were found to be (a) rather thick and long radiating structures accompanied by radiolucent linear structures parallel to some of the spicules, (b) absence of calcifications, (c) radiolucent areas in the central body of the lesion, (d) an average mean size of 6 mm and (e) changing image in different views. Most of the lesions, 73% (8/11), were in moderately dense breasts and there was no specific relation to the right or left breast. A majority of radial scars, 64% (7/11), were found in the upper outer quadrants, 27% (3/11) in the lower outer quadrants and 9% (1/11) in the lower inner quadrant. Literature shows that histology uses many synonyms for radial scars and therefore team work between the radiologists and pathologists is suggested for better conformity of the diagnosis.