Eosinophils and serum eosinophilic cationic proteins in interleukin-2-based immunotherapy for cancer

BACKGROUND: Extramedullary hematopoiesis (EMH) occurs in many disorders, including thalassemias and other hemoglobinopathies, and commonly presents in the spleen and liver. We present a case of spinal cord compression in a patient with beta-thalassemia intermedia, and review the literature and available treatment options. PATIENT AND METHODS: A 35-year-old black female with beta-thalassemia intermedia presented with a 3-week history of back pain and lower extremity weakness. Neurologic examination was consistent with spinal cord compression, and gadolinium enhanced magnetic resonance imaging (MRI) confirmed this diagnosis. She was given intravenous steroids and radiotherapy was begun in 200 cGy fractions to a total dose of 2000 cGy. RESULTS: At the completion of radiotherapy the patient was ambulatory with mild residual weakness. MRI scans 16 months later showed smaller, but persistent masses, and she remains asymptomatic 5 years from her diagnosis. CONCLUSION: Recognition of spinal cord EMH requires prompt physical examination and MRI for accurate diagnosis. EMH can be managed with radiation, surgery, transfusions, or a combination of these therapies. Radiation in conservative doses of (750-3500 cGy) is non-invasive, avoids the surgical risks of potentially severe hemorrhage and incomplete resection, and has a high complete remission rate in the majority of patients. Relapse rates are moderate (37.5%), but retreatment provides excellent chance for second remission.