S2572 Post-Liver Transplantation Lymphoproliferative Disorder Presenting as Biliary Stricture

Abstract

INTRODUCTION: A 63 year-old man with non-alcoholic steatohepatitis (NASH) cirrhosis who underwent orthotopic liver transplant (OLT) presented 1 year later with obstructive jaundice due to a biliary stricture. Further investigation revealed encasement of the bile duct by a tumor, later determined to be post-transplant lymphoproliferative disorder (PTLD). PTLD represents a rare cause of post-OLT biliary stricture. CASE DESCRIPTION/METHODS: Post-transplant course was complicated by Grade 2 acute rejection, necessitating high-intensity immunosuppression. He later developed laboratory derangements, intermittent fevers, weight loss, and sweating episodes which were ascribed to active cytomegalovirus (CMV) and Epstein-Barr Virus (EBV) viremia. One year post-transplantation, an acute elevation in total bilirubin prompted an MRCP which revealed a soft tissue mass arising from segment VIII of the liver, extending into the porta hepatis and encasing the common bile duct at the surgical anastomosis. Biopsy showed diffuse large B cell lymphoma, later classified as stage IV disease with diffuse lymph node and bony metastasis. His tacrolimus was discontinued and systemic chemotherapy with R-CHOP was initiated. DISCUSSION: PTLD includes a heterogenous group of lymphoproliferative disorders that occur after solid organ or allogenic hematopoietic stem-cell transplantation, generally in the setting of EBV. PTLD may occur in up to 5.5% of adults following liver transplant. The clinical presentation of PTLD is heterogenous, and may range from incidental findings to fulminant organ failure. Treatment for PTLD consists of reduction of immunotherapy and systemic chemotherapy regimens, such as R-CHOP. Biliary complications after OLT are reported in up to 40% of cases, and usually involve biliary strictures. Biliary strictures are classified as anastomotic or non-anastomotic and are usually secondary to vascular or surgical complications. Post-OLT biliary stricture resulting from PTLD is quite rare. This case demonstrates the difficulties of prevention and diagnosis of PTLD-related biliary stricture. The presence of acute rejection necessitated high-intensity immunosuppression, which predisposed the patient to both CMV and EBV. These active viral infections were used to explain persistent “B symptoms” and abnormal laboratory findings that may have actually been the direct result of PTLD. This case illustrates the need to consider PLTD-related biliary stricture in any post-OLT transplant patient presenting with obstructive jaundice.Figure 1.: This demonstrates an isointense mass on T2-weighted imaging, which involves hepatic segment 8 and extends towards the porta hepatis with resultant stricture of the post-transplant biliary anastomosis and subsequent intrahepatic biliary dilatation.Figure 2.: On diffusion weighted imaging, the mass demonstrates marked diffusion restriction, with corresponding low signal on ADC.Figure 3.: 18F-FDG PET demonstrates intense FDG uptake within the mass, with multifocal hypermetabolic metastatic disease involving several lymph node groups as well as multiple osseous structures.