Ultrasound-guided mammotome vacuum biopsy for the diagnosis of impalpable breast lesions

Objectives To assess the diagnostic accuracy of ultrasound-guided mammotome vacuum biopsy in impalpable breast lesions. Methods Seventy-three patients who presented with impalpable breast lesions that were suspicious for malignancy at mammography and/or sonograpby were included in the study. In the first instance the women underwent ultrasound -guided fine-needle aspiration cytology, then, 3 days later, histological b iopsy with an ultrasound-guided mammotome device. The patients with both cy tological and histological diagnoses of malignancy underwent surgery; those with a negative (for malignancy) cytological diagnosis, but with a histolo gical diagnosis of atypical hyperplasia or sclerosing adenosis, underwent s urgical biopsy. Results The diagnostic accuracy of fine-needle aspiration cytology was 67.2 %; the sensitivity was 86.7%, the specificity was 48.4%, the negative predi ctive value was 78.9% and the positive predictive value was 61.9%. In compa rison, the diagnostic accuracy of histological sampling by mammotome vacuum biopsy was 97.3%; the sensitivity was 94.7%, the specificity was 100%, the negative predictive value was 94.6% and the positive predictive value was 100%. Thus there was a statistically significant difference in diagnostic a ccuracy between fine-needle aspiration cytology and mammotome vacuum biopsy (67.2% vs. 97.3%; chi (2) test, P < 0.001). The 2.7% (2/73) failure rate o f mammotome biopsy was likely to be due to an error in the positioning of t he needle. The subsequent surgical biopsy proved that two cases, negative f or malignancy by mammotome biopsy, were in fact malignant. Conclusions Our data confirm the value of sonography for the diagnosis of b reast carcinoma in the preclinical phase and the efficacy of ultrasound sam pling using a mammotome device to confirm the diagnosis in impalpable breas t lesions.