Needle core biopsy can reliably distinguish between benign and malignant papillary lesions of the breast

To review 21 screen-detected papillary lesions in which the core biopsy findings suggested a papillary lesion and to correlate pathological and radiological findings in order to assess the risks of associated malignancy and the need for surgical intervention. The appropriate management of non-malignant papillary breast lesions detected on needle core biopsy (NCB) is currently uncertain.

Forty-seven papillary breast lesions with a histological diagnosis of papilloma, papilloma with atypical ductal hyperplasia (ADH) or ductal carcinoma in situ (DCIS), multiple papillomas, 'papillomatosis' or papillary carcinoma (invasive or in situ) were identified from records at the Leeds Breast Screening and Assessment Unit. The cases were diagnosed between between May 1995 and May 2002. In 21 cases the previous NCB contained a papillary proliferation which had been categorized as either 'B2', benign, 'B3', of uncertain malignant potential, or 'B4', suspicious of malignancy. All of the 19 'B3' or 'B4' cases and one of the two 'B2' lesions had undergone open surgical biopsy. All cases with a previous 'B4' were malignant on subsequent excision. All excised cases with a previous 'B3' or 'B2' were found benign, although four of the 'B3's derived from papillomata associated with an atypical proliferation amounting to ADH. In three of these four (75%) the papillary proliferation had been associated with epithelial hyperplasia of usual type (HUT) on the core and the radiological features were of a mass lesion detected on incident round screen which had increased in size.

Our results confirm the accuracy of NCB in the diagnosis of screen-detected papillary lesions of the breast. Surgical excision may not always be necessary following a 'B3' core biopsy.