G-CSF Production by Undifferentiated Pleomorphic Sarcoma with Leukemoid Reaction Occurred in the Lower Leg: A Case...

A 46-year-old woman presented with a mass in the lower leg and severe leukocytosis. Diffuse uptake in the bones was detected with F-fluorodeoxyglucose positron emission tomography with computed tomography (F-FDG PET/CT) imaging. The serum granulocyte-colony stimulating factor (G-CSF) was elevated, and immunostaining for G-CSF was positive. When diagnosed as G-CSF-producing undifferentiated pleomorphic sarcoma (UPS), a wide resection was performed. The leukocytosis and serum G-CSF were remarkably improved after tumor resection. No local recurrence or metastasis was detected.

We report the first case of inflammatory UPS in the extremity which demonstrated the neoplastic production of G-CSF. In our case, F-FDG PET/CT, the serum G-CSF, and immunostaining for G-CSF were useful for diagnosis.