[Diffuse large B-cell lymphoma relapsing with intravascular large B-cell lymphoma-like perivascular and intravascular lesions].

A 64-year-old woman was diagnosed with diffuse large B-cell lymphoma (DLBCL) in 2013. After eight courses of R-CHOP therapy followed by local irradiation of the remaining retroperitoneal soft tissue shadow, complete response was confirmed on 18F-2-fluoro-2-deoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT). Early in 2016, patient's serum LDH and soluble IL-2 receptor levels elevated. With suspected recurrence of DLBCL, FDG-PET/CT was performed that showed no lymphadenopathy or abnormal FDG uptake. By the end of July 2016, the patient developed fever and night sweating. Intravascular large B-cell lymphoma (IVLBCL) was suspected, and the patient underwent random skin biopsies, which revealed large atypical cells infiltrating peripheral and intravascular regions of the subcutaneous adipose tissue. Cell morphology, immunostaining, and PCR analysis of the immunoglobulin heavy chain gene suggested the recurrence of DLBCL. Despite salvage chemotherapy and autologous peripheral stem cell transplantation with high-dose chemotherapy, approximately 15 months later, DLBCL recurred and involved the lungs. The patient again received chemotherapy and achieved a second remission. Because DLBCL may recur like intravascular lymphoma, the same tests used for IVLBCL diagnosis are required in cases of suspected recurrence of DLBCL based on clinical and laboratory findings.