Department of Pathology, JIPMER, Puducherry, India.
Department of Medical Oncology, JIPMER, Puducherry, India.
Breast J. 2020 Dec;26(12):2371-2375. doi: 10.1111/tbj.14056. Epub 2020 Sep 22.
Metaplastic Breast Carcinoma (MBC) is a rare heterogeneous group of tumors, the incidence of which is less than 1% of breast tumors. These are a unique set of tumors with varying subtypes, poor prognosis, and an increased chance of distant metastasis. We aimed to study the clinical, histomorphological, and immunohistochemical (IHC) features of Metaplastic Breast Carcinoma (MBC). This was a descriptive study of cases diagnosed as MBC at a tertiary care center in Southern India from January 2015 to December 2019. A total of 20 cases were diagnosed whose clinical, histomorphological, and IHC features were studied. PD-L1and CD8 IHC were performed and analyzed in 12 cases. The median age of presentation was 50 years. Seventy percent (14/20) patients were postmenopausal women. On excision, 75% (15/20) showed mixed typed MBC, the remainder showing epithelial type MBC. Metastasis to axillary lymph node was seen only in 20% (4/20) of the cases. Thirty percent (6/20) of the cases belonged to stage 3 disease and 5% (1/20) of the cases belonged to stage 4 disease with liver metastasis. Estrogen receptor (ER), Progesterone receptor (PR) were negative in all the cases, Her2neu was positive in three cases. Ki67 labeling index was greater than 14% in all the cases. PD-L1was positive in 41.5% of the cases and intratumoral CD8 positive lymphocytes were increased in 83.3% of the cases. MBCs are tumors occurring in elderly postmenopausal women, presenting with large tumor size, have lesser chances of lymph node metastasis, and a higher chance of recurrence and hematogenous spread. They are negative for ER, PR, Her-2 neu, with a high Ki67 index and a strong PDL-1 expression.
化生性乳腺癌（MBC）是一组罕见的异质性肿瘤，其发病率低于 1%的乳腺肿瘤。这些是一组独特的肿瘤，具有不同的亚型、不良的预后和增加远处转移的机会。我们旨在研究化生性乳腺癌（MBC）的临床、组织形态学和免疫组织化学（IHC）特征。这是一项在印度南部的一家三级保健中心对 2015 年 1 月至 2019 年 12 月期间诊断为 MBC 的病例进行的描述性研究。共诊断出 20 例，研究了其临床、组织形态学和 IHC 特征。对 12 例进行了 PD-L1 和 CD8 IHC 检测和分析。中位发病年龄为 50 岁。70%（14/20）的患者为绝经后妇女。切除后，75%（15/20）表现为混合性 MBC，其余为上皮性 MBC。仅 20%（4/20）的病例发生腋窝淋巴结转移。30%（6/20）的病例属于 3 期疾病，5%（1/20）的病例属于 4 期疾病，伴肝转移。所有病例的雌激素受体（ER）、孕激素受体（PR）均为阴性，Her2neu 阳性 3 例。所有病例的 Ki67 标记指数均大于 14%。PD-L1 阳性率为 41.5%，肿瘤内 CD8 阳性淋巴细胞增加率为 83.3%。MBC 发生在老年绝经后妇女，肿瘤较大，淋巴结转移的机会较少，复发和血行播散的机会较高。它们对 ER、PR、Her-2 neu 均为阴性，Ki67 指数高，PDL-1 表达强。
