Choi Young J, Pinto Marguerite M, Hao Liming, Riba Ali K
Department of Pathology, Yale University School of Medicine, New Haven, CT 06520, USA.
Mod Pathol. 2008 Oct;21(10):1224-37. doi: 10.1038/modpathol.2008.106. Epub 2008 Jun 27.
The distinction between lobular neoplasia and infiltrating lobular carcinoma from ductal neoplasia and infiltrating duct carcinoma with equivocal histologic features may present a challenge as this distinction has important therapeutic implications. Although E-cadherin staining has been of value in helping to make this determination, the variability of the E-cadherin staining pattern and the immunohistochemistry techniques can be problematic in clinical practice. A total of 161 cases of breast lesions previously diagnosed as lobular neoplasia and infiltrating lobular carcinoma were selected from the departmental files. Three surgical pathologists interpreted them in a blinded manner for the histology diagnoses and E-cadherin staining. E-cadherin staining was conducted on the paraffin-embedded sections of the breast lesions using two different source antibodies. Our results using morphology and E-cadherin stain agreed with the previous diagnoses of lobular neoplasia and infiltrating lobular carcinoma in 140 of 161 cases (86.9%). Among the 140 cases, three pathologists agreed with the morphologic diagnoses of lobular neoplasia and infiltrating lobular carcinoma in 100 (71.4%), two pathologists in 26 (18.6%) and one pathologist in 14 (10%). All three pathologists disagreed with the previous diagnoses of lobular neoplasia and infiltrating lobular carcinoma but reevaluated as ductal lesions in 21 cases (13.0%). E-cadherin staining was confirmatory in 136 of total 161 cases (84.5%) of both lobular and duct lesions by showing the loss of staining in lobular lesions and the presence of complete membrane staining in duct lesions. Aberrant E-cadherin reactions were retained weak or partial incomplete thin membrane reaction in lobular-type lesions and reduced membrane reaction in ductal-type lesions were seen in 25 of the total 161 cases (15.5%). E-cadherin immunoreaction with two different antibodies showed discrepant results in 5 of 78 cases tested (6.4%). This study illustrates (1) interobserver variability of the morphologic diagnoses of lobular neoplasia/infiltrating lobular carcinoma and duct neoplasia/infiltrating duct carcinoma, (2) the occasional presence of aberrant E-cadherin stain pattern in these breast lesions and (3) variability of E-cadherin immunostaining results by two different antibodies.
小叶肿瘤与浸润性小叶癌和导管肿瘤与浸润性导管癌之间的区别，在组织学特征不明确时可能构成挑战，因为这种区别具有重要的治疗意义。尽管E-钙黏蛋白染色有助于做出这一判断，但E-钙黏蛋白染色模式的变异性以及免疫组织化学技术在临床实践中可能存在问题。从科室档案中选取了161例先前诊断为小叶肿瘤和浸润性小叶癌的乳腺病变病例。三位外科病理学家以盲法对其进行组织学诊断和E-钙黏蛋白染色解读。使用两种不同来源的抗体对乳腺病变的石蜡包埋切片进行E-钙黏蛋白染色。我们利用形态学和E-钙黏蛋白染色得出的结果与先前对161例病例中的140例（86.9%）小叶肿瘤和浸润性小叶癌的诊断一致。在这140例病例中，三位病理学家对小叶肿瘤和浸润性小叶癌的形态学诊断达成一致的有100例（71.4%），两位病理学家达成一致的有26例（18.6%），一位病理学家达成一致的有14例（10%）。三位病理学家均不同意先前对小叶肿瘤和浸润性小叶癌的诊断，但重新评估为导管病变的有21例（13.0%）。在161例小叶和导管病变的病例中，E-钙黏蛋白染色在136例（84.5%）中具有确诊意义，表现为小叶病变中染色缺失，导管病变中出现完整的膜染色。在161例病例中的25例（15.5%）可见异常的E-钙黏蛋白反应，小叶型病变中保留微弱或部分不完全的薄膜反应，导管型病变中膜反应减弱。在78例检测病例中的5例（6.4%），两种不同抗体的E-钙黏蛋白免疫反应结果存在差异。本研究表明：（1）小叶肿瘤/浸润性小叶癌和导管肿瘤/浸润性导管癌形态学诊断的观察者间变异性；（2）这些乳腺病变中偶尔存在异常的E-钙黏蛋白染色模式；（3）两种不同抗体的E-钙黏蛋白免疫染色结果存在变异性。
