“Incidental” Intraductal Papillomas: Is Excision Necessary?
Paul S Weisman, Brian J Sutton, Kalliopi P Siziopikou, Julie Franz, Stephen M Rohan, Megan E Sullivan. Northwestern University, Chicago, IL
Background: Intraductal papillomas (IDP) have classically become clinically apparent either due to patient symptoms or through discovery of a mass on imaging. Once diagnosed on needle core biopsy (NCB), excision is the standard of care due to the known association with higher grade lesions including cancer. However, as imaging has improved, asymptomatic IDPs that are not mass associated are being diagnosed: the "incidental" IDP. In this context, the appropriate next clinical step is unclear. In this study we retrospectively review all NCB with IDP over a 5 year period and correlate with imaging findings to determine the risk of upgrade for incidental IDPs.
Design: After IRB approval, the pathology database was reviewed for NCB with a diagnosis of IDP between 1/03 and 12/07. All available NCB slides were reviewed blinded to the specific original diagnosis (DX). Cases in which the reviewed DX conflicted with the original DX were re-reviewed by a second pathologist to establish consensus. Imaging was reviewed and mass associated IDPs were excluded. Incidental IDPs were categorized as either microscopic (MicIDP - in a single core) or multiple (MultIDP - fragmented or in multiple cores). Atypia in the NCB was noted. Excision pathology was recorded; for this study an upgrade is defined as a patient who had no known ipsilateral cancer pre-excision & whose final pathology showed ductal carcinoma in situ (DCIS) or invasive carcinoma.
Results: Out of 12353 NCB performed in the date range, 224 were IDP (2%). Slides from 207 were available for review, 45 of which were not associated with a mass on imaging and were included in the study. 89% were stereotactic NCB targeting calcifications and 11% were MRI NCB targeting non mass like enhancement. The maximum microscopic size in a single core ranged from <0.1-0.4 cm for MicIDP and from 0.2-0.9cm for MultIDP. Excision pathology was available in 24/45 (53%). The only upgrades were associated with cores showing atypia (2/5; 40%). No incidental IDPs without atypia on NCB were upgraded at excision (0/14). In the 21 patients with incidental IDPs that did not undergo excision, 1 went on to develop ipsilateral grade 1 DCIS (average FU = 55 mo; range 29-89).
Conclusions: Surgical excision is necessary when atypia is associated with an incidental IDP, as there is a significant risk of upgrade. However, incidental IDPs without atypia showed no upgrades at excision regardless of microscopic size. Of the non-excised IDPs, only 1 patient developed subsequent DCIS (interval=22 mo). With careful pathology-radiology correlation, incidental IDPs without atypia likely do not require surgical excision.
Tuesday, March 20, 2012 9:30 AM
Poster Session III # 16, Tuesday Morning