Malignant phyllodes tumor metastatic to the lung with osteogenic differentiation diagnosed on fine needle aspiration biopsy: A case report

Abstract

BACKGROUND: Osteosarcomatous differentiation in malignant phyllodes tumors is rare.# No cases of either primary or metastatic lesions were identified in the literature that were initially diagnosed on fine needle aspiration biopsy. CASE: Cytologic and histologic findings of a metastatic malignant phyllodes tumor with osteosarcomatous differentiation in a 63-year-old woman are presented. This case was diagnosed initially on fine needle aspiration biopsy and confirmed with histologic examination of the pulmonary lesion. CONCLUSION: Although rare, the differential diagnosis of metastatic phyllodes tumor should be considered in the appropriate clinical setting when examining a pleomorphic spindle cell tumor with heterologous elements on fine needle aspiration biopsy