How is atypical papilloma differentiated from small, peripheral intraductal papilloma (IDP)?

Updated: Dec 25, 2019
  • Author: Joshua I Warrick, MD; Chief Editor: Chandandeep Nagi, MD  more...
  • Print


Atypical papilloma is a controversial diagnosis. As with IDP (S/P ST), it has a fibrovascular core with overlying epithelial and myoepithelial layers, but, in contrast to IDP, atypical papilloma is involved by an epithelial proliferation similar to that seen in atypical ductal hyperplasia (ADH) or DCIS. For this reason, it has also been referred to as "DCIS involving a papilloma." Although atypical papilloma more commonly presents in the differential diagnosis with IDP (L/C ST), it occasionally presents as a smaller, IDP (S/P ST)–sized lesion.

The diagnostic criteria for atypical papilloma are not well established, and there is considerable interobserver variability in diagnosis between pathologists. These discussions are beyond the scope of this article.

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!