Successful treatment of severe extremity pain in myelofibrosis with low-dose single-fraction radiation therapy.

Myelofibrosis (MF) is characterized by cytopenias/cytoses, leukoerythroblastic blood picture, bone marrow fibrosis, and extramedullary hematopoiesis. Extremity bone pain can be a feature of MF. There has been one case report of a patient with MF and bone pain treated with radiation. We treated five patients with MF and extremity pain with radiation at our institution between 2004 and 2010. All patients had severe pain unresponsive to narcotic medication. Radiation was one fraction of 100 to 600 cGy. Most patients saw improvement in the pain within days and achieved a complete response within days to weeks.The response lasted between 1 month and 2 years. Retreatment was performed in four patients and achieved a durable response in three patients. No patients reported any acute or late side effects from radiation.Bone involvement in MF can cause disabling pain, but single-fraction low-dose radiation is a safe and effective treatment, often leading to a durable response. Retreatment is also safe and effective inpatients who experience recurrent pain.