Non-palpable tumour of the breast--radiological presentation.

During the period between 1977 and 1979, mammographic spot localizations were performed in 52 patients for evaluation of suspected occult neoplasms. Twenty-eight patients were found on biopsy to have a malignancy; on the remaining 24 patients the finding proved to be benign. The mammographic abnormalities were divided into two groups: (a) those associated with microcalcification and (b) those in which the abnormality was manifested by a small mass or localized distortion of the breast parenchyma. In many instances it was not possible to differentiate benign disease from malignancy on the mammogram. None of the 28 patients with malignant tumour had axillary node involvement at surgery.