Table 1.

Reporting Categories of Needle Biopsies [2]

Category	Terminology	Meaning
B1	Normal tissue or uninterpretable	Normal or unsatisfactory biopsy which is: 1) uninterpretable because of artefact* 2) composed of stroma only* 3) composed of normal breast tissue where normal appearances are felt to be inconsistent with findings on imaging and clinical examination*
B2	Benign	Usual ductal hyperplasia, sclerosing adenosis, fiboradenoma, involutionary calcification, periductal mastitis, hamartoma
B3	Benign but of uncertain biological potential	Papillomas, radial scars/complex sclerosing lesions, lobular intraepithelial neoplasia (LIN), atypical epithelial proliferation of ductal type (AEDT) depending on grade and extension sometimes B4, phylloides tumor
B4	Suspicious	Changes suggestive of in situ or invasive malignancy but a categorical diagnosis cannot be made because of artefact or because the appearances are borderline
B5	Malignant a) in situ b) invasive c) uncertain whether in situ or invasive d) other malignancies	Unequivocal malignant process

*: indication for a second biopsy.