Fine-wire localization and biopsy of non-palpable breast lesions.

We have undertaken fine-wire localization and biopsy of 130 impalpable breast lesions identified by mammography and considered suspicious of malignancy. Histologically 22 of these lesions were invasive carcinomas and 24 were in situ carcinomas (35 per cent malignant). Twenty-nine per cent of the lesions were identified during the screening of asymptomatic women. In the remainder, the presenting symptoms bore no relation to the eventual histological diagnosis. Clusters of microcalcification were more often malignant than were abnormal soft-tissue masses. Malignancy in the absence of microcalcification was almost always invasive.