Risk of malignancy when microscopic radial scars and microscopic papillomas are found at percutaneous biopsy

The objective of our study was to assess the incidence of associated malignancy when microscopic radial scars and microscopic intraductal papillomas are encountered at percutaneous biopsy for lesions that otherwise reveal benign histopathology.

A search of the pathology database for the period from December 14, 2006, through December 21, 2009, identified patients with a microscopic radial scar, a microscopic intraductal papilloma, or both at percutaneous biopsy. Patients whose percutaneous biopsy was performed for a lesion that revealed carcinoma or a high-risk pathology result were excluded to avoid confounding bias, as were patients who had only imaging follow-up. Only patients who underwent surgery solely for the study lesion were included. The lesion type that prompted core biopsy, biopsy guidance and device, sample number, and surgical outcomes were recorded. The incidences of benign, high-risk, and malignant pathology findings from surgery were calculated.

The search revealed 35 patients (18 microscopic radial scars, 17 microscopic papillomas) who underwent surgery solely for the study lesion. Stereotactic guidance was used for 15 (43%); ultrasound, for 12 (34%); and MRI, for eight (23%). At surgery, 12 patients (34%) had high-risk histopathology results and 23 (66%) had benign results. No study lesions were upgraded to malignancy.

Our study found no evidence of associated malignancy at surgical excision when microscopic radial scars and microscopic intraductal papillomas were encountered at percutaneous biopsy in patients who otherwise had benign histopathology results; thus, routine imaging follow-up may be performed.