Intravascular large B-cell lymphoma presenting as cholecystitis and pancytopenia: case report with literature review.

Intravascular large B-cell lymphoma (IVLBCL) is a rare variant of extranodal diffuse large Bcell lymphoma with only a few more than 300 cases reported. It is characterized as lymphoma cells confined to the lumina of small vessels, so patients usually do not present with masses or lymphadenopathy. Clinical presentations of these patients are non-specific and the pathologic changes may be subtle, which often leads to delayed diagnoses and, in many instances, a postmortem diagnosis. IVLBCL can essentially involve the vessels of any organ, but it is quite rare for the gallbladder to serve as the initial presenting site; there are only four such cases reported in the English literature. Furthermore, IVLBCL of the gallbladder with peripheral blood involvement is even less common. We report a recent case of IVLBCL presenting as acute cholecystitis and pancytopenia. The patient underwent a simple cholecystectomy. Examination of the gallbladder showed clusters of large lymphoma cells within lumina of small vessels in the gallbladder wall. These cells were positive for CD5/CD20 and negative for CD3, CD10, and TdT. Based on these findings, a diagnosis of IVLBCL was made. Coincidently, circulating lymphoma cells were identified in the peripheral blood and confirmed by flow cytometric analysis (positive for CD19/CD20/CD5, without light chain expression). The patient was started on chemotherapy but subsequently died of chemotherapy related multi-organ failure 10 days after the initial diagnosis.