Stereotaxic aspiration biopsy in the evaluation of mammographically detected clustered microcalcification.

Background: Stereotaxic fine-needle aspiration biopsy (SFNA) of mammographically detected nonpalpable lesions of the breast provides accurate diagnosis and may eliminate many unnecessary excisional biopsies of areas of microcalcification.

Methods: SFNA of microcalcification of indeterminate radiologic significance was performed on 125 patients (1991-1994), yielding 130 specimens (2 sites in 2 patients and bilateral aspirations in 3 patients). Stereotaxic localization was performed, and samples from within the area of microcalcification were obtained using 22-gauge needles. Smears stained with a Giemsa-type stain were prepared and studied by a cytopathologist during the procedure to determine the adequacy of each specimen.

Results: Of 130 specimens, 104 (80%) were cytologically benign, 13 (10%) were atypical, 6 (4.6%) were suspicious, and 7 (5.3%) were malignant. All malignant diagnoses were confirmed by subsequent operative biopsy. Follow-up was available in 74 of 104 benign cases (71%): surgical excisions (all benign) in 8 cases and follow-up mammograms at 6 months to 5.8 years in 66 cases (no radiologic change in 64 cases and 2 [1.9%] cases with new radiologic findings [SFNAs of the new radiographic abnormality revealed adenocarcinoma in both]).

Conclusions: SFNA is a reliable and cost-effective method of evaluating indeterminate microcalcification; however, mammographic follow-up is indicated because of the possibility of subsequent and independent cancers.