Posttransplantation lymphoproliferative disorders in pediatric patients undergoing liver transplantation

To study the clinicopathologic and molecular genetic findings in posttransplantation lymphoproliferative disorders (PTLDs) following pediatric liver transplantation and to determine the applicability of a recently proposed consensus classification system.

The clinical, pathologic, and molecular genetic findings of 11 PTLDs that occurred in 10 patients are presented. These 10 patients were derived from a group of 121 pediatric patients who underwent liver transplantation at the University of California, San Francisco. The PTLDs were classified using the proposed Society for Hematopathology scheme. Clonality was determined by immunohistochemical detection of monotypic immunoglobulin or by using polymerase chain reaction-based methods to detect monoclonal immunoglobulin heavy-chain gene rearrangements. Epstein-Barr virus (EBV) was detected by immunohistochemistry, in situ hybridization, or polymerase chain reaction. Epstein-Barr virus typing and the presence of LMP1 gene deletions were also analyzed by polymerase chain reaction.

There were 3 early lesions, 4 polymorphic PTLDs, and 4 monomorphic PTLDs. Monoclonality was demonstrated in 8 of 9 cases assessed. Epstein-Barr virus was present in all cases; of 9 cases assessed by polymerase chain reaction, the virus was type A in 8 and type B in 1. No EBV LMP1 gene deletions were identified. The corresponding liver explants were negative for EBV in 8 cases and positive in 1 case. Greater than 3 foci of disease and monomorphic PTLD were associated with decreased actuarial survival (P <.05).

The prognosis of pediatric patients with PTLD is favorable for early lesions and polymorphous PTLD, particularly in patients with localized disease. Multifocal disease and monomorphic PTLD are associated with an unfavorable prognosis.