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Needle biopsy of the breast.

Recently, there has been a considerable increase in the use of both fine-needle aspiration biopsy (aspiration cytology) and tissue-core needle biopsy of the breast. In patients with suspected breast cancer, needle biopsy is frequently used to confirm the diagnosis before treatment is planned. This allows a more thoughtful approach to the patient and full screening for possible metastatic disease prior to definitive surgery. Needle biopsy techniques are simple, rapid, can be performed in the doctor's office, and save time, equipment, and hospital beds. Complications are few. Aspiration cytology has the advantage that it is quick to perform, the preparation can be examined almost immediately and, in the event of an unsatisfactory smear, the procedure can be repeated. However, the diagnosis is based on purely cytological evaluation, and the information obtained is somewhat limited. Reported accuracy rates range from 42 to 96%. False positive reports are rare but have occurred in most centers, and a high degree of accuracy will only be obtained by experienced practitioners. Tissue-core needle biopsy has the advantage that the diagnosis is based on histopathological assessment, but the procedure is slightly more time consuming, is more traumatic for the patient, and the equipment is more expensive. Accuracy rates range from 67 to 98.5%. During the past 4 years, 329 tissue-core (Tru-Cut) biopsies have been performed in the Guy's Hospital Breast Unit, with an accuracy rate of 83% in the diagnosis of carcinoma. The procedure has been acceptable to most patients, and complications have been minimal. Studies comparing the use of aspiration cytology and tissue-core needle biopsy in the diagnosis of mammary carcinoma have produced variable results. Both methods have advantages and disadvantages, and the choice of technique must depend on the clinical situation and the preferences and skills of the practitioners involved in the management of the patient.