Determining the Upgrade Rate of De-novo Breast Intraductal Papillomas to Malignancy, its Related Risk Factors, and 6-Month Outcome After Treatment.

Intraductal papillomas (IDPs) are benign breast lesions with potential for malignant transformation. This study aimed to determine the upgrade rate of de-novo IDPs to malignancy, identify associated risk factors, and assess the 6-month outcome after treatment. This retrospective cohort study included 320 patients diagnosed with de-novo IDP at a breast surgery clinic in Tehran, Iran, between March 2011 and March 2022. Patients were divided into upgraded (malignant) and non-upgraded (benign) groups based on pathology results from core needle biopsy (CNB) or vacuum-assisted excision (VAE). Baseline characteristics, pathology outcomes, and follow-up outcomes were analyzed. Multivariable logistic regression identified risk factors for malignant upgrade. Of the 320 participants, 16 (5.0%) had upgraded (malignant) IDPs, and 304 (95.0%) had non-upgraded (benign) IDPs. The median age was significantly higher in the upgraded group (53 years) compared to the non-upgraded group (43 years) ( < 0.001). Age ≥ 50 years was a significant risk factor for malignant upgrade (,  < 0.001). The most common malignant pathology was ductal carcinoma in situ (DCIS) (68.8%). Age was identified as a significant risk factor for malignancy, with older age increasing the likelihood of an upgrade (OR = 1.249,  = 0.02). After 6 months follow-up, three patients with IDP were detected by sonography. Older age was the sole significant risk factor for malignant transformation of IDPs. Continuous follow-up is recommended, especially for older patients, to promptly detect potential recurrence or malignant progression.