Unusual spontaneous improvement in Asian variant of intravascular large B-cell lymphoma

The clinical course of the Asian variant of intravascular large B-cell lymphoma (AIVL) is generally very aggressive. We describe a case of AIVL demonstrating an unusual clinical course, with spontaneous improvement. An 81-year-old man with high-grade fever and thrombocytopenia was admitted to our hospital. Although we could not confirm the origin of his symptoms, they disappeared completely without intervention within 2 weeks. Three months later, however, thrombocytopenia reappeared and progressed. Finally, he was readmitted due to a subdural hemorrhage with high fever and he finally died of rapidly progressive multiple organ failure. Autopsy findings revealed the presence of B-cell lymphoma cells in microscopic vessels of many organs as well as hemophagocytosis in the bone marrow. He was diagnosed with AIVL with an unusual indolent clinical course with spontaneous improvement.