摘要目的 探讨乳腺基底样浸润性小叶癌(ILC)的临床病理特点、临床进展及预后.方法 对4例乳腺基底样ILC进行病理形态学观察,并采用MaxVision法进行免疫组织化学E-cadherin、p120 catenin、雌激素受体(ER)、孕激素受体(PR)、HER2、CK5/6、表皮生长因子受体(EGFR)、p63、p53、Ki-67染色,对其进行随访和分析并回顾相关文献.结果 4例乳腺基底样ILC,1例为混合型,3例为多形型.免疫组织化学染色肿瘤细胞3例E-cadherin阴性,1例少部分胞膜阳性；p120 catenin 均为胞质阳性,l例少部分除细胞质阳性外有少部分细胞膜阳性；ER、PR及HER2均呈“三阴性”；CK5/6和EGFR均呈不同程度阳性；p63 2例阳性；p53阳性或弱阳性；Ki-67阳性指数为30％ ～ 75％.2例有腋窝和锁骨下淋巴结转移,3例获得随访,其中2例发生胸壁转移,1例同时发生肝转移和腹部转移.结论 乳腺基底样ILC癌细胞异型性大、核级高、核分裂象多,免疫表型ER、PR及HER2“三阴性”,CK5/6和EGFR阳性,符合基底样亚型,易发生邻近部位和远处组织或器宫转移,对化疗反应差,预后较差.

abstractsObjective To investigate the clinicopathologic features,clinical progress and prognosis of the basal-like subtype of invasive lobular carcinoma (ILC) of the breast.Methods Four cases of ILC were analyzed by detailed histopathologic observation and immunohistochemical staining for E-cadherin,p120 catenin,ER,PR,HER2,CK5/6,EGFR,p63,p53,Ki-67 using MaxVision method.The follow-up and clinical data were analyzed.Results Morphologically,one case was mixed ILC and three cases were pleomorphic ILC.The tumor cells were negative for E-cadherin except one case with focal membrane positivity,and all showed p120 catenin cytoplasmic positivity except one case with focal membrane positivity.All cases were negative for ER,PR and HER2 (triple negative),and positive for EGFR and CK5/6.Two cases were positive for p63.The cases were partly and weakly positive for p53,and the Ki-67 positive rate was between 30％ and 75％.Follow-up data showed that two cases developed chest wall metastases,and in one case,there was progression to liver and abdominal metastases.Conclusions ILC of the breast are ER,PR and HER2 "triple negative",CK5/6 and EGFR positive,indicative of basal-like characteristics.Basal-like subtype of ILC are peculiarly prone to metastasis and poor response to chemotherapy,suggesting that it is associated with poor prognosis.