Intravascular Large B-cell Lymphoma with a Pulmonary [18F]-Fluorodeoxyglucose Uptake.

A 58-year-old woman was referred to our hospital with a 3-month history of recurrent fever and weight loss. Computed tomography (CT) revealed normal findings of the bilateral lungs (Picture 1A) and splenomegaly (Picture 1B). Laboratory examinations revealed elevated levels of soluble interleukin-2 receptor (sIL-2R; 6,774 pg/mL). A subsequent examination using [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET) showed a high uptake in the spleen, and curiously, the bilateral lungs (Picture 1C and D). A transbronchial lung biopsy specimen (Picture 2A and B) and a partially resected spleen specimen (Picture 2C and D) were examined pathologically, and a definitive diagnosis of intravascular large B-cell lymphoma (IVLBCL) was confirmed. The most common symptom of IVLBCL is a fever, and it often demonstrates a pulmonary FDG uptake even in the absence of chest CT abnormalities (1,2). For the early diagnosis of IVLBCL, serum sIL-2R and FDG-PET/CT should be examined in patients presenting with a fever of unknown origin.

Picture 1.

Picture 2.

The authors state that they have no Conflict of Interest (COI).