Meningeal recurrence of intravascular large B‐cell lymphoma: early diagnosis with PET‐CT

Abstract

A 50-year-old woman with a history of pyrexia of unknown origin, weight loss and constitutional symptoms was diagnosed with intravascular large B-cell lymphoma. The trephine biopsy confirmed the presence of CD19+, CD20+, CD79a+ large lymphoid cells, with prominent nucleoli, lodged intraluminally. Initial staging with [18F]-fluorodeoxyglucose (FDG) combined positron emission tomography – computed tomography (PET/CT) demonstrated left axillary nodal disease and diffuse increased bone marrow uptake. She was treated with six cycles of R-CEOP (rituximab, cyclophosphamide, epirubicin, vincristine and prednisolone). Early PET-CT re-staging after two cycles of R-CEOP demonstrated a complete metabolic response and bone marrow examination demonstrated complete remission. In view of high-risk disease, consolidation treatment with carmustine, etoposide, cytarabine and melphalan (BEAM) chemotherapy plus autologous stem cell transplantation was undertaken in first remission. The transplant course was uncomplicated with neutrophil engraftment on day 12. Routine restaging at 3 months post-transplant with a bone marrow examination showed no evidence of lymphomatous infiltration. On clinical review 2 weeks later, she was asymptomatic except for a several-day history of a vague intermittent headache. A routine PET-CT at this time demonstrated striking intense uptake in the spinal canal extending from L1 to L5 levels. There was further intense uptake in subcentimetre right axillary lymph nodes, and further focal bony uptake in the right clavicle, sternum, humeri and femora, without abnormality on CT bony windows. Subsequent lumbar puncture revealed heavy infiltration with lymphocytes confirming meningeal lymphoma recurrence. Treatment with salvage chemotherapy was undertaken, with an early re-staging PET study after one cycle demonstrating a complete metabolic response. Intravascular large B-cell lymphoma is a rare subtype of diffuse large B-cell lymphoma. It is characterised by the presence of lymphoma cells in the lumina of small vessels resulting in highly variable end-organ involvement and clinical presentation. It has a very poor prognosis, partly reflecting frequent delays in diagnosis and initiation of therapy due to its unusual presentation. This case demonstrates the utility of functional imaging with PET-CT throughout disease management, including initial staging, early re-staging and response to therapy, which resulted in the early diagnosis of disease recurrence, allowing prompt institution of appropriate salvage chemotherapy.