Malignant Phyllodes of Breast With Heterologous Differentiation: A Rare Case Report

Abstract

Sarcomas of the breast are rare neoplasms accounting for less than 1% of breast malignancy. Phyllodes tumours are rare biphasic tumours of the breast. We present a case of a 42-year-old-female with left breast mass measuring 12 x 8 cm who underwent mastectomy and on histopathological examination, a diagnosis of malignant phyllodes tumour with heterologous differentiation of osteosarcoma along with osteoclast-like giant cells and chondrosarcoma was rendered. The heterologous elements were tumour osteoid formation and tumour chondroid formation. The rarity of malignant phyllodes showing stromal elements of osteosarcoma and chondrosarcoma differentiation was considered when reporting this case.