Abstract
Granulocytic sarcoma is a rare solid malignant tumor that occurs in patients with acute myeloid leukemia. As such, granulocytic sarcoma without leukemia occurring in long bones is quite rare. This case report describes an isolated granulocytic sarcoma of the right humerus in an 82-year-old woman in the absence of acute myeloid leukemia. The patient was admitted to our hospital with a pathological fracture of the right humerus. An incisional biopsy was performed, and the pathological diagnosis was granulocytic sarcoma. Radiotherapy (45 Gy) to the humerus resulted in a good clinical outcome with no evidence of myeloid leukemia at 9.5 years of follow-up. Radiotherapy was effective for pain relief and maintenance of good quality of life in this patient. Although laboratory evaluation has not revealed any abnormalities 9.5 years after radiotherapy, periodic observation is required.