OBJECTIVE: To demonstrate the efficacy of core-needle biopsy to avoid unnecessary surgery; to assess the technical difficulties of this method; to establish decision criteria for clinical follow-up or surgery in patients with lesions classified as suspicious for malignancy (BI-RADS IV); to expedite surgery in patients with lesions classified as highly suspicious for malignancy (BI-RADS V). MATERIALS AND METHODS: The patients were submitted to clinical examination, mammography and ultrasound. Core-needle biopsy was done using a 14-gauge needle, and 4-8 cores per lesion were obtained. RESULTS: A hundred lesions were studied, 47 of them underwent surgery and biopsy, and 34 cancers were diagnosed. In 23 lesions classified as probably benign (III) only one case of cancer was diagnosed (4.34%). In 43 lesions classified as IV, seven (16.28%) cancers were found whereas in 34 lesions classified as V, 26 (76.47%) cases of cancer were identified. It was possible to avoid surgery in 53 cases (53%). Difficulties in core-needle biopsy occurred in seven cases including insufficient material, risk of malignancy due to sclerosing lesions and lack of correlation between imaging and core-needle biopsy results. All the core biopsy diagnoses of malignancy were confirmed by surgery. There was one false negative result when the core biopsy specimen examination showed atypical hyperplasia while surgery specimen analysis revealed a carcinoma. There were no false positive cases.

Keywords: Breast disease, Breast cancer, Core-needle biopsy, Breast ultrasound