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Scientific Comments
Rev Bras Hematol Hemoter. 2012;34(5):323-33
A step towards the cure of Burkitt’s lymphoma in developing countries
The outcome of sporadic Burkitt’s lymphoma (BL) in high-income countries may
be considered excellent due to its overall cure rate of roughly 90%
(1-4)
. Three major US
and European childhood cancer groups [Lymphoma malignancy B-cell (LMB), Berlin-
Frankfurt-Munster (BFM), Children’s Cancer Group/Children Oncology Group (CCG/COG)]
contributed to the most effective treatment strategies to date. Nevertheless, the treatment has
pronounced toxic effects such as long periods of mucositis, hematological toxic effects as
well as the potential risk of severe infection. Assuredly, the improvement of supportive care
has contributed to these better outcomes
(1-4)
. On the other hand, in low-income countries,
therapeutic schemes need to be modified in accordance with local conditions in order to avoid
unacceptable treatment-related mortality
(5)
.
In this issue Cunha et al.
(6)
present a retrospective study of 50 cases of BL in children
and adolescents who were treated with chemotherapy regimens containing intermediate
methotrexate doses (500 mg/m
2
). The probability of overall survival was 73% (median follow-up of
35 months). The data show a favorable step with improvement in the results of BL treatment in
Brazil even considering the high mortality rate (23.8%) observed in the study. Reinforcing the
predicted tumor burden value in the prognosis of BL patients, survival was significantly lower
for patients with uric acid levels > 7 mg/dL. In addition, these results may also show that the
impact of methotrexate on the overall success may be of less importance in patients with lower
tumor load compared with those with larger tumor masses
(7)
. Thus, the efficacy of treatment
may depend as much on the number of drugs used (at least 4-6 drugs systemically) as on
their doses and so lower dose multidrug regimens may improve outcome without comparable
increases in toxicity
(8)
.
Although the study by Cunha et al.
(6)
provides important information on the approach to
BL care in Brazil, there are still several areas to be addressed. Differences among survival rates
in a large country such as Brazil are worthy of comment. The mean tumor burden at diagnosis
has an important impact on the outcome
(9)
. Even though the Brazilian Government Healthcare
System (SUS –
Sistema Único de Saúde
) covers most chemotherapy drug costs, primary
healthcare should be improved for earlier diagnosis. Moreover, supportive care facilities
remain inadequate in some Brazilian regions where resources are limited. Enhancement of
laboratory monitoring, aggressive hydratation and the use of urate oxidase in patients with high
risk of tumor lysis syndrome will result in fewer toxic events and better treatment outcomes
(10)
.
The availability of rituximab in the SUS to treat B-cell lymphomas in adult patients has led
to the possibility of obtaining excellent results in children with less toxicity by combining this
drug with chemotherapy. However, there is a question as to whether rituximab is an effective
drug in pediatric B-cell non-Hodgkin lymphoma (B-NHL). This drug was tested in a phase
II short-window study showing that it can be safely added to a pediatric chemotherapeutic
regimen
(11)
. Even so, only controlled clinical trials will allow an evaluation of the role of this
drug in the treatment of pediatric B-NHL.
Taking these considerations into account, results like those of high-income countries
may be achieved by directing research towards designing protocol regimens in formal clinical
trials with chemotherapy tailored by tumor burden. The primary goal of therapy studies
in developing countries today is to define risk groups as accurately as possible, so that the
patients receive therapy consistent with the best possible outcome while further reduction of
acute and chronic toxicity may be achieved.
References
1. Patte C,AuperinA, GerrardM, Michon J, Pinkerton R, Sposto R,Weston C, Raphael M, Perkins SL, McCarthy
K, Cairo MS; FAB/LMB96 International Study Committee. Results of the randomized international FAB/
LMB96 trial for intermediate risk B-cell non-Hodgkin lymphoma in children and adolescents: it is possible to
reduce treatment for the early responding patients. Blood. 2007;109(7):2773-80.
2. Gerrard M, Cairo MS, Weston C, Auperin A, Pinkerton R, Lambilliote A, Sposto R, McCarthy K, Lacombe
Claudete Esteves Klumb
Instituto Nacional de Câncer - INCA, Rio de
Janeiro, RJ, Brazil
Conflict-of-interest disclosure:
The author declares no competing financial
interest
Submitted: 8/17/2012
Accepted: 8/26/2012
Corresponding author:
Claudete Esteves Klumb
Instituto Nacional de Câncer- INCA
Programa de Hemato-Oncologia
Molecular, Laboratório de
Hemato-Oncologia Celular e Molecular
Praça da Cruz Vermelha No 23 – Centro
20230130 Rio de Janeiro, RJ, Brazil
Phone: 55 21 32071198
cklumb@inca.gov.br
www.rbhh.org or www.scielo.br/rbhh
DOI: 10.5581/1516-8484.20120087