Intravascular Large B-cell Lymphoma Associated with Systemic and Central Nervous System Hemophagocytic Lymphohistiocytosis: A Case Report.

We present a case of an Asian variant of intravascular large B-cell lymphoma associated with systemic and central nervous system hemophagocytic lymphohistiocytosis (HLH) with multiple neurologic manifestations.A 68-year-old, previously healthy, Korean woman presented with a 4-week history of fever and weight loss. She had pancytopenia with neutropenia, a ferritin level of 5030 μg/L, and elevated liver enzyme levels. Bone marrow, liver biopsy specimens, and cerebrospinal fluid demonstrated hemophagocytosis. The patient was treated with the HLH-2004 protocol, but her disease relapsed 3 months later. A repeated liver biopsy specimen confirmed the initially missed diagnosis of intravascular large B-cell lymphoma, a known driver of HLH in patients of Asian origin. She was then treated with lymphoma-directed therapy and had a prompt resolution of fever and neurologic symptoms as well as normalization of her blood cell counts and ferritin level.This case serves as a reminder that patients with an Asian variant of intravascular large B-cell lymphoma frequently present with HLH and neurologic manifestations, including seizures, strokes, and cognitive deficits. A high index of suspicion is needed for prompt diagnosis and initiation of lymphoma-directed therapy.