Flow cytometry used to identify histiocytic sarcoma: A case report.

Histiocytic sarcoma (HS) is an extremely rare but aggressive malignancy of hematopoietic origin. The diagnosis of HS mainly relies on pathological morphology and immunohistochemical staining combined with clinical symptoms. However, whether histiocytic sarcoma can be detected using flow cytometry (FCM) is not clear.