Intravascular large B-cell lymphoma (IVL) is a rare subtype of large B cell lymphoma that is characterized by the proliferation of lymphoma cells within the lumina of small blood vessels, particularly capillaries and post-capillary venules, without an obvious extravascular tumor mass or readily observable circulating lymphoma cells in the peripheral blood.
The clinical presentation is varied and often includes symptoms related to organ dysfunction caused by occlusion of blood vessels. [Freedman AS, UpToDate]
The diagnosis of IVL is made postmortem in over 50% of the cases.
IVL can affect virtually any organ in the body. Central nervous system (CNS) IVL had the highest proportion of postmortem diagnosis, 60% compared to 8% of skin, 11% of bone marrow and spleen, and 7% of lung IVL’s.
Age <70 years, non-CNS site of initial diagnosis, lactate dehydrogenase (LDH) <700, and rituximab treatment were favorable prognostic factors. [Fonkem E, 2014]
A 58-year-old man was referred to our hospital with a symptoms of stroke, weakness in the left hand and epileptic seizure (grand mal). Also, in his history 3-month of recurrent fever. Cerebral CT and MR imaging were performed and not showed abnormal results. The EEG study and lumbar puncture were normal. On physical examination, absence of peripheral lymphadenopathy, splenomegaly and skin lesions. Laboratory studies yielded elevated values of serum lactate dehydrogenase at 4000 U/L. Blood cell counts are normal with a hemoglobin level of 7.0 g/dL. Findings on both chest radiography and computed tomography (CT) of the lungs were unremarkable. However, positron emission tomography (PET)/CT with 18F-fluorodeoxyglucose (FDG) revealed diffuse uptake in the bilateral lung, predominantly in the upper fields. In addition, FDG uptake was slightly heterogeneous in the bone marrow with small focal accumulation sites and a little elevated in the cortex of the kidneys. Tests for viruses, bacteria and autoimmune diseases were negative. On bone marrow biopsy, pathological cells were not confirmed. Random skin biopsy specimens from normal-appearing skin on the patient’s thigh revealed CD20+ large lymphoid cells filling the small vessels in the subcutaneous tissues. IVL was diagnosed.
On the basis of 15 clinical IVL cases recorded in the literature, FDG-PET findings demonstrated diffuse FDG uptake in the lung (47.8%). The other reported abnormal foci of FDG uptake were in the bone marrow (57.0%), spleen (30.0%), renal cortex (22.0%), uterus/vagina (17.4%), adrenals (13.0%), lymph nodes (8.7%) and stomach (4.0%). From an anatomic viewpoint, these organs are affected by IVL cells because are rich in small blood vessels. [Shiiba M, 2014]
Posted on 26.04.19