Fine-needle aspiration in the management of breast masses

The exact role of FNA in the diagnosis of palpable breast lesions is still uncertain. False-positive and false-negative cytological diagnoses occur and raise questions regarding the diagnostic utility of FNA as a replacement for open biopsy in many clinical situations. False-positive diagnoses may result from atypical epithelial proliferations, fibroadenomas, or inflammatory lesions. False-negative aspirates may occur because of technical errors, cystic lesions, and underdiagnosis of low grade neoplasms. The triple diagnosis protocol has been suggested as a replacement for open biopsy of palpable breast masses in many clinical situations. Following this algorithm, the results of palpation, mammography, and cytology are combined to guide management. Mammography should precede FNA or follow the cytologic procedure by 2 or more weeks. Patients with a positive triple diagnosis should undergo open biopsy or confirmatory intraoperative frozen section. Positive FNA results would be useful for preoperative counselling as well as serving as a diagnostic procedure for clinically suspicious lesions in patients wishing a confirmatory test before open biopsy is performed. Patients with discordant triplet results should be referred for open biopsy. The management of patients with negative triplet results is less clear. From the available data, it appears that approximately 2 percent of patients with negative triplet results have carcinoma. Based on these results, we cannot recommend replacing open biopsy by the triple diagnosis method in most patients with a persistent dominant mass. In most cases, a biopsy is indicated. Surgeons, who plan to follow a breast mass with clinical examination, may be able to reduce their false-negative rate by performing FNA. Further study is necessary to establish the best way to use FNA in the diagnosis of breast carcinoma, to determine the cost effectiveness of the triple diagnosis method as a substitute for open biopsy, and to assess the utility of aspiration cytology in the mammographically directed diagnosis of nonpalpable breast lesions.