title: Metastatic leiomyosarcoma of the uterus with heterologous differentiation to malignant mesenchymoma.
abstract: Heterologous differentiation in metastatic leiomyosarcomas of uterine origin is an extremely rare phenomenon. We report a remarkable case of a metastatic leiomyosarcoma from the uterus with an unusual pattern of tumor progression to malignant mesenchymoma after chemotherapy. The patient, an 80-yr-old woman with a history of metastatic leiomyosarcoma of the uterus to the lungs, presented with a large intra-abdominal mass. Histologic examination of the intraperitoneal mass demonstrated a high-grade sarcoma containing various heterologous malignant mesenchymal elements including osteosarcoma, chondrosarcoma, a liposarcoma-like area, and osteoclast-like multinucleated giant cells. Only the identification of small areas of smooth muscle differentiation revealed the true nature of the tumor as a metastatic leiomyosarcoma with aberrant sarcomatous differentiation. This unique presentation emphasizes the importance of clinicopathologic correlation in the diagnosis of tumors with unusual histology.
authors: Department of Pathology, Florida Hospital Orlando, Orlando, FL 32803, USA. trannguyentienanh@hotmail.com
authors: Tien
authors: T
authors: Anh Tran
authors: Robert W
authors: RW
authors: Holloway
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D007890:Leiomyosarcoma / Q000473:pathology*; D008175:Lung Neoplasms / Q000556:secondary*; D008637:Mesenchymoma / Q000473:pathology*; D014594:Uterine Neoplasms / Q000473:pathology*