Risk of invasive breast cancer and ductal carcinoma in situ in women with atypical papillary lesions of the breast.

Benign papillary lesions of the breast include papilloma and papillomatosis. A retrospective analysis of patients with a papillary breast lesion diagnosed between October 1992 and December 2009 was performed. Patients were excluded if they had a previous or concurrent diagnosis of invasive or in situ cancer or less than 6 months of follow-up. The Kaplan-Meier method was used to determine the risk of developing subsequent malignancy. The log rank test was used to compare groups of patients. Median follow-up for the 167 patients included in the study was 4.6 years. Fifty-one patients had a papillary lesion with atypia and 116 patients had a papillary lesion without atypia. Patients with a papillary lesion with atypia were more likely to develop invasive or in situ breast cancer with a 5 year risk of 13.0% versus 4.6% in patients with no atypia (p = 0.03).