Abstract
A 78-year-old woman with a remote history (1987) of liver transplantation, hepatitis C infection, and chronic active EBV infection. She was treated successfully for her hepatitis C infection and was on immunosuppressive therapy for organ transplantation with sirolimus. She recently presented with skin lesions on her ankle and thigh, and a biopsy showed neoplastic cells with a T-cell phenotype and diffuse expression of MUM1 and BCL2 and a high proliferative index with Ki-67. The neoplastic cells were positive for EBV. The findings support diagnosis of post-transplant lymphoproliferative disorder (PTLD) of T-cell phenotype, and the non-specific immunophenotypic changes suggested subclassification as peripheral T-cell lymphoma (PTCL), not otherwise specified (NOS). PTLD is a rare but serious complication of organ transplantation, which is seen in 1.0 to 5.5% of people with liver transplant. PTLD is often associated with EBV infection or reactivation, although other risk factors such as recipient age, transplanted organs, type of immunosuppression, and genetics are important. The most common type of PTLD is monomorphic PTLD. Although most monomorphic PTLD are of B-cell type, up to 15% are of T-cell or natural killer-cell type as in this case. Because the phenotypic findings did not indicate a specific T-cell lymphoma subset, this case was subclassified as PTCL, NOS, a rare and aggressive form of PTLD that can be nodal or extranodal. Skin involvement accounts for a small percentage of extranodal disease (16%). This case is unique as it highlights an uncommon presentation of skin involvement greater than 30 years following organ transplantation.