Mucinous cystadenocarcinoma of the breast with a basal‐like immunophenotype

• DOI: 10.1111/j.1440-1827.2012.02810.x
• Publication Date: 2012-03-22T18:04:44Z
• Authors: Yunte Deng; Debin Xue; Xiaoyan Wang; Sanpeng Xu; Qilin Ao; Zhiyong Hu; Guoping Wang
• Keywords: Mucinous cystadenocarcinoma; Mucinous carcinoma; Immunophenotyping; Cystadenocarcinoma

Mucinous cystadenocarcinoma (MCA) of the breast is extremely rare and was only recently described as a distinct variant invasive ductal carcinoma breast. A case MCA reported in 41‐year‐old woman. Mammographic ultrasonographic examinations showed an irregularly shaped 10.0 × 8.0 5.5 cm lesion with patching calcification upper outer quadrant left The gross examination revealed that tumor has well‐circumscribed edge gelatinous cut surface hemorrhage necrosis were also noticed mass. Microscopically, mass resembled mucinous cystic neoplasm ovary pancreas closely, areas lined by columnar cells associated abundant extracellular intracellular mucin, which distinctively different from typically nests low grade neoplastic floating mucin pool. positive for CK7, CK20 CDX2 negative displayed typical immunophenotype basal‐like cancer (ER, PR, HER2 negative, CK5/6 EGFR positive). Metastatic identified three 14 axillary lymph nodes. We describe here very unusual immunophenotype.