Metastatic undifferentiated pleomorphic sarcoma causing intraoperative stroke.

[dedifferentiated liposarcoma]

Malignant Fibrous Histiocytoma was historically the most commonly diagnosed soft tissue sarcoma of adults . In 2002 , the World Health Organization declassified malignant fibrous histiocytoma as a formal diagnostic entity . They recommended renaming the disease "Pleomorphic Undifferentiated Sarcoma ". Current thoughts about the origin of this tumor are being debated . We report a case of a dedifferentiated liposarcoma that metastasized to the lung within one year . The histologic morphology of the metastasis was more aggressive than the primary lesion , and was consistent with a pleomorphic undifferentiated sarcoma . Following surgical resection of the metastatic pulmonary lesion , the patient never fully regained consciousness . He expired the day following his surgery . At autopsy , the patient was found to have died from a massive hemorrhagic stroke involving almost the entire left cerebrum . Tumor emboli from the pulmonary metastasis were seen in the left middle cerebral artery , causing the cerebral infarct . The embolic lesion was consistent with a pleomorphic undifferentiated sarcoma . This case illustrates the evolution that soft tissue sarcomas can undergo as they metastasize and become increasingly undifferentiated , and confirms the surgical risk of resecting such lesions .