[Two cases of successfully treated intravascular lymphoma presenting with fever and dyspnea].

We report two patients with intravascular large B-cell lymphoma who presented with fever and dyspnea. Serum level of lactate dehydrogenase (LDH) and soluble interleukin-2 receptor (sIL-2R) levels were extremely high in both cases. Chest CT revealed tumor mass and ground glass opacity in one patient, and no abnormality in another patient who had severe hypoxemia. Their perfusion ventilation lung scintigraphy demonstrated multiple defects, and gallium scintigraphy showed abnormal accumulation in both lungs, and the spleen. Both patients were successfully treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Initial chemotherapy was followed by high dose systemic chemotherapy with peripheral blood stem cell support. Intravascular large B-cell lymphoma should always be considered in the differential diagnosis of fever and hypoxemia with elevated serum LDH and sIL-2R, regardless of the chest CT findings.