Aggressive primary hepatic histiocytic sarcoma: case report and literature review

Histiocytic sarcoma is an uncommon non-Langerhans histiocyte disorder of mature tissue histiocytes. The authors presented an example of this rare tumor in a 14-year-old girl who presented with left upper quadrant pain, loss of appetite, and weight loss. A large 18 cm × 10 cm heterogeneous solid and cystic enhancing mass was found in the left lobe of the liver. Based on the histomorphology and positivity for histiocyte-specific markers in a needle biopsy, a diagnosis of histiocytic sarcoma was made. Chemotherapy was initiated, but the tumor did not respond well, and she died about 7 weeks following initial diagnosis with multi-organ failure. At autopsy, the tumor showed extensive necrosis, with no evidence of metastatic spread. In conclusion, the diagnosis of histiocytic sarcoma is challenging, and requires a high index of suspicion, with an appropriate panel of confirmatory immunohistochemical stains. Recognition of this rare tumor is important because of its poor response to chemotherapy and high mortality.