A comparison of the use of the "Tru-Cut" needle and fine needle aspiration cytology in the pre-operative diagnosis of carcinoma of the breast.

Two methods of obtaining a pre-operative diagnosis of carcinoma of the breast are compared. Tru-Cut needle biopsy was carried out on 368 consecutive patients with palpable breast lumps, and both Tru-Cut biopsy and fine needle aspiration cytology were performed during part of this study on 163 of the patients. A final histological diagnosis was obtained in each patient, at excision biopsy or mastectomy. There were 278 patients with carcinoma and 90 with benign breast disease. A correct positive diagnosis of carcinoma was made by the Tru-Cut method in 73.5% of cases, but in only 52% of cases by aspiration cytology. More importantly, there were no false positive diagnoses of carcinoma with Tru-Cut biopsy, but five cases of benign breast disease were incorrectly diagnosed as carcinoma by aspiration cytology. It is concluded that Tru-Cut biopsy is sufficiently reliable to be able to proceed direct to mastectomy following a positive diagnosis of carcinoma, in distinction to aspiration cytology with which an unacceptably high number of false positives occurs. The benefits of a pre-operative Tru-Cut biopsy diagnosis are identified.