Geographic variation in Epstein‐Barr virus–associated Burkitt's lymphoma in children from Brazil

Abstract

In developing countries, BL has a strong association with EBV infection during childhood. In South America, the data have shown an EBV association intermediate between that reported in the United States (30%) and that in equatorial Africa (95%). Early age at EBV infection and lower socioeconomic status have been related to increased EBV-associated BL in developing countries. In Brazil, there are not enough data on childhood BL related to EBV infection. Our aim was to evaluate the clinicopathologic features and EBV association of 44 children with NHL from the state of Rio de Janeiro, situated in the southeast of Brazil. EBV was detected using RNA in situ hybridization in 36 biopsy specimens. DNA from fresh tumor samples and from paraffin-embedded tissues of patients were analyzed by PCR, in which the first reaction included primers for an EBNA-2 common region while the nested reaction amplified the region discriminating between EBV types 1 and 2 in separate reactions. EBV was detected in 21 of 29 BLs (72%), and type 1 virus infected the majority of EBV-positive BLs (18/21). There was a trend for younger age in children with EBV-positive BL compared to EBV-negative BL (median age 4 compared to 6 years, respectively; p ‫؍‬ 0.056). Our study confirmed that in the southeast of Brazil BL had an intermediate association with EBV. A higher rate of EBV-associated BL was described in the northeast of Brazil. These differences are probably related to regional socioeconomic status. In conclusion, our study suggests that early infection with EBV in the background of a low socioeconomic condition associated with other environmental factors could contribute to BL in Brazil.

Clinical and demographic characteristics of Epstein-Barr virus-associated childhood Burkitt's lymphoma in Southeastern Brazil: epidemiological insights from an intermediate risk region

“…Patients at advanced (III/IV) stages (75%) were younger than stage I/II patients (median 4.5 vs. 7 years; Mann-Whitney test, p=0.03). This seems to be a characteristic of Brazilian BL, 4,5,8 contrary to that observed in a large series in Kenya, where stages I/II were predominant in childhood BL. 16 Abdominal involvement was unrelated to age class, while in older patients, a trend of nodal involvement was evident (χ 2 =5.48; p=0.064).…”

“…The frequency of EBV association was intermediate between eBL (95%) and sBL (10-30%), 1,4 predominantly of type 1 (Table 1), as previously reported in Brazil. 5,8,17 In immunocompetent children, a significant association between EBV infection and lower age was observed (χ 2 =10.24; p=0.006) (Figure 1 A-B). EBV + BL showed a median age of 4 years, against a median of 8 years in EBV-negative cases (Mann-Whitney test; p=0.002).…”

“…The clinical characteristics of 29 patients have been previously described. 5 Histopathological diagnosis was performed according to the WHO classification. 2 Statistical analyses were based on non-parametric methods and a p value <0.05 was considered significant.…”

“…3 An alternative classification to the standard types, based on three different epidemiological conditions, considers: (i) BL in areas of high risk or incidence (endemic), (ii) BL in areas of low risk or incidence (sporadic cases in USA, Northern and Eastern Europe, and Japan), and (iii) BL in areas of intermediate risk or incidence (Northern Africa, the Middle East, and northern and central regions of South America). 3 BL in Brazil might be included in this third subtype, 4,5 although the epidemiological status of BL, in a geographically extensive and heterogeneous country like Brazil, remains poorly understood. We report a study of 54 children with BL in Southeastern Brazil and analyse their clinicopathological characteristics and EBV association.…”

Plasma Epstein-Barr viral load predicting response after chemotherapy for post-transplant lymphoproliferative disease

“…Immunohistochemistry revealed the following phenotypes CD20+, CD30-, CD10-, CD3-, TdT-and BCL6-. The association with EBV was confirmed by in situ hybridisation for Epstein-Barr-encoded RNAs (EBERs) and latent membrane protein immunohistochemistry (LMP1) as previously described [8,9]. According to St. Jude's criteria, the patient had stage II [10].…”