The follow-up excision (FUE) results were analyzed from 370 cases diagnosed as intraductal papilloma on breast core needle biopsy (CNB) with no history of malignancy or other risk factors. Of these cases, 98.6% were rendered a Breast Imaging Reporting and Data System score of 4 on mammography before the CNB. Fifty-one cases (13.8%) were found to have microcalcifications on microscopic examination of CNB. A total of 7 (1.9%) of 370 cases were upgraded to invasive carcinoma, ductal carcinoma in situ, or pleomorphic lobular carcinoma in situ on FUE. Six of 51 (11.8%) cases with microcalcifications found on imaging and CNB were upgraded to ductal carcinoma in situ or invasive carcinoma, whereas only 1 (0.3%) of 319 cases without microcalcifications was upgraded to pleomorphic lobular carcinoma in situ (P = .003). Results of a multivariate analysis adjusted for age confirmed that microcalcifications was a risk factor for upgrading to cancer, independent of age. Our results indicate that surgical excision is required for intraductal papilloma diagnosed on CNB if microcalcifications are present. However, excision may not be required for those who have no microcalcifications on CNB and no other known risk factors.