Benign

This chapter defines a benign FNAB and describes and illustrates the cytological features characteristic of specific benign neoplastic and non-neoplastic breast lesions. For each specific entity the clinical and imaging findings are described, and the key cytological diagnostic criteria are listed. The differential diagnosis and potential pitfalls in interpretation and diagnosis are discussed with emphasis on avoiding a false-positive diagnosis. This is particularly relevant in the diagnosis of fibroadenoma and intraductal papillomas. The category also includes a number of lesions that do not require an epithelial component for definitive diagnosis if the features are concordant with the clinical and radiological findings, including breast abscess, cysts, fat necrosis and granulomatous inflammation. Guidelines for optimal management are provided, tailored to different clinical settings with different resource facilities. Finally, a range of sample reports are provided to facilitate optimal communication with the clinical team.