Intraductal Papilloma of the Breast: Prevalence of Malignancy and Natural History Under Active Surveillance.

Background: The optimal management of intraductal papillomas (IPs) without atypia diagnosed on needle core biopsy (NCB) is unclear. This study analyzed the malignancy risk of immediately excised IPs and characterized the behavior of IPs under active surveillance (AS).

Methods: We retrospectively reviewed the pathology and imaging records of patients diagnosed with IPs without atypia on NCB during a 10-year period (1999-2019).