Diffuse Large B-Cell Lymphoma in the Portal Vein

Tumor thrombus in the portal vein without any liver parenchymal abnormality is extremely rare. In the liver, the primary tumor most frequently presenting with intravascular tumor thrombi is hepatocellular carcinoma and lymphoma is rarely considered. Even though thrombosis occurs quite often in lymphoma, cases of tumor thrombus are rare and cases of tumor thrombus in the portal vein are even rarer. Only four cases of lymphoma with portal vein tumor thrombosis have been reported to date and all cases were the result of direct extensions of a dominant nodal or extra-nodal mass. To our knowledge, there has been no report on diffuse large B-cell lymphoma (DLBCL) presenting only within the lumen of the portal vein and not intravascular B-cell lymphoma. We present the first case of DLBCL presenting only within the lumen of the portal vein in an immunocompetent patient.