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Updated: Feb 4, 2026

Intraductal Delivery to the Rabbit Mammary Gland
Published on: March 9, 2017
Are we overtreating intraductal papillomas?
Sayee Kiran1, Young Ju Jeong2, Maria E Nelson1
1Division of Breast, Endocrine and Soft Tissue Surgery, Department of Surgery, Norris Comprehensive Cancer Center and Los Angeles County + USC Medical Center, University of Southern California, Los Angeles, California.
Background:
The management of intraductal papillomas (IDPs) diagnosed on core needle biopsy (CNB) remains controversial regarding whether excision is required. We evaluated whether excision of IDPs might be overtreatment based on a consecutive patient population where all IDPs were routinely excised.
Materials And Methods:
We retrospectively reviewed the records of consecutive patients treated with excision of IDPs at our institution from 2009 to 2016. We evaluated the rate of upgrade of IDPs on CNB and factors predicting for malignant upgrade.
Results:
Of 153 CNB specimens, 136 (88.9%) were IDPs without atypia and 14 (9.2%) showed atypia. The overall upgrade rate on final pathology was 7.3% with 1.3% for invasive cancer, 2.7% for ductal carcinoma in situ, and 3.3% for atypical ductal hyperplasia. Of the 14 patients with atypia on CNB, two of these patients (14.2%) were found to have ductal carcinoma in situ. In the absence of atypia on CNB, upgrade rates were 1.5% for invasive and 1.5% for in situ carcinoma. Personal history of breast cancer and magnetic resonance imaging-guided biopsy predicted for malignant upgrade.
Conclusions:
IDPs on CNB have a low chance of harboring an occult malignancy. Given the low probability of upgrade to invasive breast cancer, it is reasonable to consider watchful surveillance in the absence of a prior personal history of breast cancer or atypia on CNB.
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