Single-center "Argentine" analysis of post-transplant lymphoproliferative disorders: incidence, histopathological characteristics and EBV status

ABSTRACT

ABSTRACT Introduction: Post-transplant lymphoproliferative disorders (PTLDs) are a heterogeneous group of lymphoid proliferations occurring after solid organ or bone marrow transplantation. The primary aims of our study were to characterize cumulative incidence of PTLDs, clinical and pathological features according to the Epstein-Barr virus (EBV) status and survival. Methods: This was a retrospective cohort study on adult and pediatric patients, from January 2001 to December 2017. The cumulative incidence of PTLD was calculated by analyzing all the patients transplanted at our hospital, based on the database of the Organ Donation and Ablation Authority of Argentina (INCUCAI). The Kaplan-Meier method was used to plot the survival. Results: Fifty-eight cases of biopsy-confirmed PTLD were identified and 12 cases of clinical data were incomplete and these patients were excluded. The median age at the time of the PTLD diagnosis was 17.5 years (interquartile range [IQR] 9 - 57). The median interval between transplant and PTLD diagnosis was 39 months (IQR 9 - 113). The most commonly transplanted organ was the liver (24 cases, 52.2%), followed by kidney (20 cases, 43.5%). The Epstein-Barr encoding region in situ hybridization (EBER ISH) was positive in 29 (69.8%) of the 43 evaluable biopsies. The PTLD cumulative incidence was 1.84% (95%CI 1.77 - 1.91) for solid organ and 0.84% (95%CI 0.48 - 1.2) for bone marrow transplant patients. The overall survival rate at 5 years was 0.77 (95%CI 0.61 - 0.87). Subgroups by the EBV EBER status, transplant type, PTLD subtype and age group (adult vs. pediatric) showed no statistically significant association with the overall survival. Conclusion: The PTLD incidence was similar to that of previous series and the EBER did not appear as a relevant factor in our patient survival.