Intravascular large B-cell lymphoma with multi-organ failure presenting as a pancreatic mass: a case with atypical presentation and definite diagnosis postmortem.

Intravascular large B-cell lymphoma (IVLBCL) is a very rare extra nodal lymphoma that tends to proliferate within small blood vessels, particularly capillaries and postcapillary venules while sparing the organ parenchyma. The cause of its affinity for the vascular bed remains unknown. Because of its rarity and unremarkable clinical presentation, a timely diagnosis of IVLBCL is very challenging. Here, we describe a case of IVLBCL presenting as pancreatic mass that was ultimately diagnosed at autopsy. A 71-year-old Caucasian female presented with a 3-month history of fatigue, abdominal pain, and weight loss. She was referred to the emergency room with a new diagnosis of portal vein thrombosis and lactic acidosis. During her hospital course she was found to have a 1.9 × 1.8 cm lesion in the pancreatic tail on imaging; The cytologic specimen on the mass showed a high-grade lymphoma. A bone marrow biopsy showed no involvement. The patient's condition rapidly deteriorated and she, later, died due to multi-organ failure. An autopsy revealed diffuse intravascular invasion in multiple organs by the lymphoma cells. Based on our literature review-and to the best of our knowledge-there are virtually no reports describing the presentation of this lymphoma with a discernible tissue mass and associated multi-organ failure. The immunophenotypic studies performed revealed de novo CD5+ intravascular large B-cell lymphoma, which is known to be aggressive with very poor prognosis. Although it is a very rare lymphoma, it should be considered as a potential cause of multi-organ failure when no other cause has been identified. A prompt tissue diagnosis, appropriate high-dose chemotherapy and stem cell transplantation remain the only viable alternative to achieve some kind of remission.