PATHOLOGY OF R4 SPICULATED LESIONS IN THE BREAST SCREENING-PROGRAM

Small spiculated carcinomas are indistinguishable from benign radial s car/complex sclerosing lesions on mammography, leading to a radiologic al assessment of R4 (suspicious, probably malignant, The cytological a nd pathological features of 80 screen detected R4 spiculated lesions w ere reviewed. The analysis showed that there were 46 radial scars, of which 38 were benign and 8 (17%) contained foci of ductal carcinoma in situ (DCIS), and 34 spiculated carcinomas. The majority of radial sca rs showed some degree of epithelial hyperplasia (assessed semi-quantit ively) but the cellularity of the lesion as a whole was not related to the presence of DCIS. In 20 cases no aspiration was attempted for cyt ology but 40% were inadequate and only one lesion containing DCIS had cytology C4 or C5, Diagnosis of radial scar was made in all cases by l ocalization biopsy, The carcinomas ranged in size between 4 and 15 mm (mean 8.9 mm) and were of grade 1 (21 = 63%) or grade 2 (12 = 37%). Th ere were 16 infiltrating ductal carcinomas of no special type, 12 tubu lar carcinomas, three lobular carcinomas, two ductal and lobular mixed , and one mucinous carcinoma. Only one patient with carcinoma was node -positive, For the carcinomas, 12 (35%) yielded C5 (malignant) cytolog y allowing pre-operative diagnosis.