不明熱と著明な高CRP血症で発症したde novo CD20陰性びまん性大細胞型B細胞リンパ腫の１例

A ６８-year-old woman presented with sustained fever for more than １ month and admitted due to hematemesis and systemic edema. Computed tomography scan revealed swelling of the cervical, paraaortic lymph nodes. Blood test results showed severe anemia, elevation of white blood cell count, elevation of liver enzyme and coagulopathy with high C-reactive protein. Biopsy of the right cervical lymph node showed proliferation of abnormal lymphoid cells with necrosis and hemorrhage, which are positive for CD７９α, CD３０, MUM‐１, and bcl‐６ and negative for CD２０, CD５, CD１０, ALK, CD３８, CD１３８, and EBER. Gene rearrangement of immunoglobulin heavy chain was detected in tumor cells. Bone marrow aspiration showed tumor involvement. The patient was diagnosed with de novo CD２０‐negative diffuse large B-cell lymphoma（DLBCL）stage IV B. Reduced CHOP therapy was performed under artificial respiration due to pulmonary edema and takotsubo cardiomyopathy. Although her general condition and high CRP levels temporarily improved, she died ４７ days after admission due to rapid relapse. De novo CD２０‐negative DLBCL was rare and presented with high CRP levels and rapid progression, and was thought to be clinically different from the existing DLBCL. It is imperative to elucidate molecular pathophysiology and establish new treatment strategy for de novo CD２０‐negative DLBCL.