Flat epithelial atypia of the breast commonly co-exists with @entity1373 , @entity1137 , and indolent forms of @entity189 such as @entity420 . Most @entity1 with pure @entity2543 on core biopsy undergo surgical excision to evaluate for @entity189 in the adjacent breast tissue. Studies to date have reported varying upgrade rates with most recommending follow-up excision. These studies have often lacked detailed radiographic correlation, central review by breast pathologists and information regarding the biology of the @entity189 identified upon excision. In this study, we report the frequency of upgrade to invasive @entity189 in situ in excision specimens following a diagnosis of pure @entity2543 on core biopsy. Radiographic correlation is performed for each case and grade/receptor status of detected @entity189 is reported. Seventy-three (73) core biopsies containing pure @entity2543 were identified from our files, meeting inclusion criteria for the study. In the subsequent excision biopsies, five (7%) cases contained invasive @entity189 in situ and seventeen (23%) contained @entity28648 . All of the @entity513 in situ cases with @entity172 receptor results were @entity172 receptor positive and intermediate grade. The invasive @entity5 were small (pT1a) hormone receptor-positive, @entity1722 -negative, low-grade invasive @entity513 with negative sentinel lymph-node biopsies. No upgrades were identified in the 14 @entity1 who had all of their @entity730 removed by the stereotactic core biopsy. Our rate of upgrade to @entity189 , once cases with discordant imaging are excluded, is at the lower end of the range reported in the literature. Given the low upgrade rate and indolent nature of the @entity189 associated with @entity2543 , case management may be individualized based on clinical and radiographic findings. Excision may not be necessary for @entity1 without remaining @entity730 following core biopsy.Modern Pathology advance online publication, 21 November 2014; doi:10.1038/modpathol.2014.159.

Management of XXXX on breast core biopsy may be individualized based on correlation with imaging studies.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1137 :: ('MESH:D018275', 'Disease') :: ['lobular neoplasia'] @entity172 :: ('MESH:D004967', 'Chemical') :: ['estrogen'] @entity1722 :: ('2064', 'Gene') :: ['HER2'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumors'] @entity1373 :: ('MESH:D006965', 'Disease') :: ['atypical ductal hyperplasia'] @entity189 :: ('MESH:D002277', 'Disease') :: ['invasive carcinomas', 'carcinomas', 'carcinoma or ductal carcinoma', 'carcinoma'] @entity513 :: ('MESH:D044584', 'Disease') :: ['ductal or tubular carcinomas', 'ductal carcinoma'] @entity730 :: ('MESH:D002114', 'Disease') :: ['calcifications'] @entity2543 :: ('MESH:D017573', 'Disease') :: ['flat epithelial atypia'] @entity420 :: ('MESH:D000230', 'Disease') :: ['tubular carcinoma'] @entity28648 :: ('MESH:D018299', 'Disease') :: ['atypical ductal hyperplasia or lobular neoplasia']
@entity2543 :: (MESH:D017573,Disease) :: ['flat epithelial atypia']
