Whole-Exome Sequencing of Metaplastic Breast Carcinoma Indicates Monoclonality with Associated Ductal Carcinoma Component

Although most human cancers display a single histology, there are unusual cases where two or more distinct tissue types present within a primary tumor. One such example is metaplastic breast carcinoma, a rare but aggressive cancer with a heterogeneous histology, including squamous, chondroid, and spindle cells. Metaplastic carcinomas often contain an admixed conventional ductal invasive or