CK免疫标记在乳腺浸润性小叶癌淋巴结分期中的应用价值

目的探讨免疫标记是否有助于提高原发性乳腺浸润性小叶癌同侧腋窝淋巴结转移的检出率。方法18例Bcadherin(E-cad)阴性乳腺浸润性小叶癌根据光镜下有无同侧腋窝淋巴结转移分组，无同侧淋巴结转移11例(A组)；有同侧淋巴结转移但仍有淋巴结阴性者7例(B组)。对A组共189枚和B组115枚“阴性”淋巴结进行cytokeratin(CK，MNFll6)免疫标记。按照WHO乳腺癌淋巴结分期标准进行分期。结果A组11例中3例共7枚“阴性”淋巴结中检出CK阳性癌细胞，散在分布于窦隙中，此3例由pN0期改为pNla期。B组7例中6例共20枚“阴性”淋巴结中检出癌细胞呈散在或小簇状分布于包膜下窦或髓窦中，1例由pNlbi改为pNlbii期。结论免疫标记有助于检出淋巴结中微小转移癌，进而精确乳腺浸润性小叶癌的淋巴结分期。

Immunostaining for cytokeratin helpful for lymph-node-staging in invasive lobular carcinoma of the breast

ObjectiveRecognition of lymph node metastases in invasive lobular carcinoma of the breast is a known problem in surgical pathology This study aims to determine whether immunohistochemical staining can improve the detection of ipsilateral lymph node metastases in primary breast invasive lobular carcinoma MethodsEleven cases with no lymph node metastases (Group A, pN0 by morphologic examination) and 7 cases with known lymph node metastases and several negative lymph nodes (Group B) were retrieved for study All selected invasive lobular carcinomas were negative for E-cadherin In total, 189 and 115 morphologically negative lymph nodes from Group A and Group B respectively were immunostained with the cytokeratin antibody MNF116 The results were analyzed according to the WHO classification of lymph-node-staging of breast carcinoma ResultsOccult lymph node metastases in the form of isolated cells in the sin uses were detected by immunostaining in 7 lymph nodes (three cases) in Group A with lymph node staging changed from pN0 to pN1a in three cases In group B, isolated cells, clusters or small sheets of CK cells were detected in 20 lymph nodes (6 cases), lymph node staging of one case changed from pN1bi to pN1bii ConclusionsThis study confirms that immunohistochemical staining for cytokeratin can aid in more accurate nodal staging in patients with invasive lobular carcinoma