“…The stromal cells can exhibit heterologous sarcomatous differentiation, while the epithelial component can become malignant with in situ or invasive carcinoma [14] . Heterologous differentiation in malignant phyllodes tumor of the breast is exceedingly rare, but there are a few reported cases of malignant phyllodes tumor with chondrosarcomatous or osteosarcomatous differentiation [13 , [15] , [16] – 17] , although the reporting of radiological features of such cases is even rarer [18] . Formation of bone or cartilage tissue in mammary tumors is rare, and as a primary breast tumor, osteosarcoma or chondrosarcoma may occur in 3 different forms: as a pure neoplasm (pure osteosarcoma or chondrosarcoma), as the stromal component of a histologically malignant phyllodes tumor, or as osteosarcomatous or chondrosarcomatous differentiation in a metaplastic carcinoma [19 , 20] .…”