Abstract
BACKGROUND: Burkitt lymphoma (BL) is a post-transplant lymphoproliferative disorder (PTLD) different from other monomorphic PTLDs (M-PTLDs). AIMS: We report clinical presentation and pathologic findings in 6 pediatric cases. METHODS: We included patients that undergone a liver transplantation (LT) at Sainte Justine Hospital (Montreal) or in The Children hospital of Lyon, from 1991 to 2017, (aged ≤18 years). During this period, 10 patients presented monomorphic PTLDs (M-PTLDs), 6 of which were Burkitt lymphoma (BL). RESULTS: The median age at transplantation, for the 6 children (5 boys, 1 girls) with BL, was 21.5 months (range 6 – 159 months), and biliary atresia was the main indication (3/6). BL had an abdominal presentation in majority of cases (5/6). Patients displayed a monomorphic population of small to intermediate-sized, non-cleaved, lymphoid elements with a “starry-sky” pattern. The immune-phenotype in patients available for analysis was CD20+ (n =6/6), CD10+ (n = 6/6), Bcl-6+ (n = 6/6), Ki-67/MIB-1 proliferation index (n = 5/5), and negative for TdT (n = 5/5). Pre-transplant Epstein-Barr virus serology was negative in 4 patients (n = 4/6). At the time of BL diagnosis, all patients showed high EBV viral loads estimated by quantitative PCR testing between 16000 and 20(6) copies/ ml. The PCR was positive since a median time of 26.5 months (range, 1–40 months). The median time from transplantation to diagnosis was 33 months (range, 3–46 months). All patients were currently alive after chemotherapy, with median disease-free time of 14.5 years from diagnosis (range, 2–19 years). CONCLUSIONS: Post-transplant-BL is strongly associated with high EBV viral loads and represented a distinct monomorphic PTLD. Managed aggressively with decreased immunosuppression and specific chemotherapy must lead to a favorable outcome. These data also lead to discuss the modality of monitoring and the establishment of early treatment, with anti CD 20, for transplanted patients who retain high EBV viral loads. FUNDING AGENCIES: Ste Justine Foundation, Servier Laboratory