[229] Acidophilic Nuclear Inclusions Are Fairly Specific for Florid Duct Hyperplasia among Proliferative Breast Lesions

S Lauer, G Oprea, A Adams, C Cohen, N Adsay. Emory University Hospital, Atlanta, GA; Grady Memorial Hospital, Atlanta, GA

Background: It is believed that breast usual ductal hyperplasia (UDH) represents a different lineage of cells than atypical ductal hyperplasia (ADH) and low-grade ductal carcinoma in-situ (LG-DCIS). Many of the cytologic features distinguishing UDH from ADH/DCIS have been well established. In 1991, Tavassoli et al noted helioid nuclear inclusions (Ultrastructural Pathol., 15(3):267) in hyperplasias; however, to the best of our knowledge there has not been any systematic study on the incidence and specificity of these inclusions.
Design: 89 cases from were selected including 40 cases of UDH, 15 cases of UDH, and 34 cases of LG-DCIS. The cases were reviewed by three pathologists who developed a consensus diagnosis for the lesion, and the presence or absence of intranulcear inclusions was documented.
Results: Two distinct types of nuclear inclusions were discerned. The first, termed white nuclear inclusions (WNI), consisted of white areas of chromatin clearing associated with an ill-defined vacuolated appearance, as well as other artifactual nuclear changes in the background, and when present tended to be widespread. The second, termed acidophilic nuclear inclusions (ANI), exhibited round, dense, sharply demarcated eosinophilic globules with occasional targetoid condensation and well defined borders. ANI were identified in 50% of cases of UDH, while none were observed in any cases of ADH or LG-DCIS. WNI were seen in 47.5% of UDH cases, but were not specific as they were also present in cases of ADH (40%) and LG-DCIS (23.5%). No inclusions of any kind were seen in 20% of cases of UDH, 60% of ADH, and 73.5% of LG-DCIS. Overall, the presence of acidophillic inclusions was significantly associated with a diagnosis of UDH compared to ADH (p=0.019) and LG-DCIS (p=0.008).
Conclusions: Acidophilic nuclear inclusions are a common, specific feature found in usual ductal hyperplasia of the breast, and may be helpful in distinguishing UDH from some cases of ADH and low grade DCIS. The significance of these inclusions is unknown, but may be related to the heliod inclusions seen by Tavassoli et al., or to the BROCNs (biotin-rich optically clear nuclei) seen in morular-type proliferations in women, which are now thought to be surrogate products of beta-catenin pathway alterations (Hum Pathol 2004, 35:869). Elucidating the nature of these inclusions may provide insight into the pathogenesis of usual ductal hyperplasia of the breast.
Category: Breast

Tuesday, March 10, 2009 1:00 PM

Poster Session IV # 7, Tuesday Afternoon