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Original Article
361
Rev Bras Hematol Hemoter. 2012;34(5):361-6
Clinical course and prognostic factors of children with Burkitt’s lymphoma in a
developing country: the experience of a single centre in Brazil
Keyla Christy Christine Mendes Sampaio
Cunha
Maria Christina Lopes Araujo Oliveira
Ana Cecília Silva Gomes
Lucia Porto Fonseca de Castro
Marcos Borato Viana
Universidade Federal de Minas Gerais –
UFMG, Belo Horizonte, MG, Brazil
Conflict-of-interest disclosure:
The authors declare no competing financial
interest
Submitted: 4/17/2012
Accepted: 6/25/2012
Corresponding author:
Maria Christina Lopes Araujo Oliveira
Departamento de Pediatria - Unidade
de Hematologia Pediátrica. Hospital das
Clínicas, Universidade Federal de Minas
Gerais – UFMG
Av. Prof. Alfredo Balena, 190
30130-100 Belo Horizonte, MG, Brazil
chrismariana@gmail.com
www.rbhh.org or www.scielo.br/rbhh
DOI: 10.5581/1516-8484.20120093
Introduction
The most frequent immunophenotype of non-Hodgkin lymphoma in children and
adolescents is B-cell lymphomas (NHL-B). Burkitt’s lymphoma (BL) is the most common
subtype, corresponding to approximately 40% of cases
(1)
; it occurs worldwide and has
endemic, sporadic and immunodeficiency-associated phenotypes
(2)
. The endemic form
classically presents as a jawbone tumor in children of African descendency. Its incidence
is high at 50–100 cases per million during the first 15 years of life
(3)
. Sporadic BL has a
low incidence and occurs without specific geographic or climatic associations. In contrast to
adults, lymph node involvement is less common among children with extranodal sites being
the most frequent presentation
(4)
. Immunodeficiency-associated BL mainly occurs in patients
infected with human virus immunodeficiency (HIV) but also occurs in allograft recipients and
in individuals with congenital immunodeficiencies
(5)
.
The pathogenesis of BL is universally associated with specific chromosomal
translocations that lead to deregulation of the
c-Myc
oncogene. Other cellular genetic changes
have been implicated in the pathogenesis including abnormalities of the p53-ARF pathways
and environmental factors such as infection with Epstein-Barr virus (EBV) and malaria
(6)
.
The interactions between these cellular and environmental events continue to fascinate the
scientific community
(7)
.
Among human neoplasms, BL has the shortest doubling time. Its unequalled proliferation
rate creates special challenges for diagnosis and treatment
(4)
.
In addition, although BL is a
highly aggressive lymphoma, 80% to 90% of children on risk-adapted chemotherapy are
cured in the developed world
(8,9)
.
The aim of this study was to contribute to the knowledge about the clinical course and
identification of prognostic factors related to death in 45 children and adolescents followed up
at a single teaching hospital over a 26-year period.
Methods
In this retrospective cohort study, the medical charts of 50 consecutive cases of children
and adolescents aged 16 years or less with
de novo
BL were reviewed. The patients were
admitted to the Pediatric Hematology Unit, University Hospital, UFMG between January
1981 and December 2007. Five patients were excluded because of previous treatment at other
institutions (n = 1), severe concomitant immunodeficiency (post-transplantation lymphoma;
Objective:
Burkitt’s lymphoma is the most common subtype of non-Hodgkin lymphoma in children. The aim
of this study was to characterize the clinical course and prognostic factors of children and adolescents with
Burkitt’s lymphoma treated in the Hematology Unit of
Hospital das Clínicas, Universidade Federal de Minas
Gerais (UFMG).
Methods:
A retrospective cohort study was made of 50 consecutive cases of children and adolescents aged 16 years
or less with Burkitt’s lymphoma admitted between January 1981 and December 2007. Prognostic factors associated
with death were evaluated using the Kaplan-Meier method and compared by the two-tailed log-rank test.
Results:
The median age at diagnosis was 4.7 years. Most patients had abdominal tumors (66.7%) and
advanced disease (68.9%) at diagnosis. Thirty-eight patients (84.4%) achieved complete clinical remission and
33 (73.3%) were alive at the first remission. Twelve children (26.7%) died. The median follow-up was 35 months
with the probability of overall survival being 73% (89.2% and 35.7% for patients with uric acid < 7 mg/dL and
≥ 7.0 mg/dL, respectively - p-value < 0.001). Uric acid was the only significant prognostic factor at diagnosis.
Conclusion:
Our findings confirm the favorable prognosis of children with Burkitt’s lymphoma even when
treated with intermediate doses of methotrexate (500 mg/m
2
). Survival was significantly lower for individuals
with concentrations of uric acid ≥ 7 mg/dL.
Keywords:
Burkitt’s lymphoma; Lymphoma, Non-Hodgkin; Child; Uric acid; Survival; Prognosis; Child