Variable Gender Male Female Age at diagnosis (months) < 48 ≥ 48 LDH (IU/L)* < 500 ≥ 500 Uric Acid (mg/dL)** < 7 ≥ 7 Potassium (mEq/L)† < 4.2 ≥ 4.2 Serum creatinine (mg/dL)# < 0.8 ≥ 0.8 Weight-age Z-score < -1.28 ≥ -1.28 Height-age Z score) < -1.28 ≥ -1.28 Clinical stage†† I-II III-IV 9 3 3 9 0 3 3 9 3 3 8 4 3 9 1 7 1 10 24 9 10 23 7 12 25 5 15 14 25 7 12 21 7 25 12 21 < 0.001 0.99 0.90 0.22 0.96 0.34 0.50 0.50 0.50 Cunha KC, Oliveira MC, Gomes AC, Castro LP, Viana MB Table 2 - Factors associated with death of children with Burkitt’s lymphoma Dead Surviving p-value (log-rank) *Available for only 22 patients at diagnosis **Available for 42 patients at diagnosis † Available for 29 patients at diagnosis †† Available for 44 patients at diagnosis - one patient died before staging # Available for 40 patients at diagnosis Discussion In Brazil, despite well-established nationwide collaborative studies for the treatment of acute leukemia and several solid tumors, the majority of children who have B-NHL are treated according to local experience and single-institution protocols. This retrospective cohort study reports the results of a single service in the State of Minas Gerais, Brazil. Most of the characteristics of BL that presented in the children studied here were similar to those reported for the sporadic forms of BL. The mean age at diagnosis of our cohort was 4.7 years, similar to that reported for the US and Europe, which ranged from 5 to 9 years(9,15). As also reported in previous studies, there was a clear predominance of males. This fact may raise the question of whether a tumor-suppressor gene for BL might be located on the X chromosome(15,16). The main clinical presentation reported among patients with sporadic BL is the presence of abdominal tumors(15). In the present study, this was also the most frequent clinical manifestation. The predominance of intra-abdominal sites, mainly in the right ileocecal region, was similar to another Brazilian study (75%) (17). In areas of endemic BL, jaw tumor is more common and may affect as many as 60% of children with one third of them 364 having involvement of the CNS at diagnosis. Outside endemic areas, the frequency of jaw involvement is around 15% and CNS involvement is uncommon, except if there is concomitant HIV infection(5,18). In our study only one patient had CNS-positive disease at diagnosis; no inherited or acquired immune deficiencies were present and this patient remains in first clinical remission. Because of high tumor growth fraction, in general, patients show up with advanced disease. So, approximately 70% to 90% of patients present widespread disease at diagnosis(4,18,19), as observed in this series. Many studies have contributed to the identification of possible risk factors for a bad prognosis, such as age, gender, response to treatment, CNS or marrow involvement, and chromosomal abnormalities, such as del(13q) and +7q(20,21). Bulky disease, estimated through staging systems, resection status and serum LDH levels, seems to be an important adverse prognostic factor(15,16,19,22). Thus, it has been shown that a high LDH concentration has a negative impact on prognosis(15,22). Among our patients, LDH was not a statistically significant factor, but LDH values were registered in only half of the patients’ records. It has also been considered that a staging system that incorporates the situation of tumor resection and LDH levels seems to be a better indicator of prognosis than disease stage alone(22). Another way of estimating bulky disease, although uncommonly used, is based on uric acid concentration at diagnosis. Advanced clinical stage, the presence of antibodies to EBV early antigen (anti-EA) and high concentrations of uric acid and LDH were associated with a significantly poorer outcome in African children with BL. The authors concluded that the tumor burden, evaluated by the high concentrations of uric acid and LDH, was the most important prognostic factor in BL(23). In a study of Buyukpamukçu et al. high levels of creatinine and urea had a significant negative impact on the survival of 104 children with NHL, 59 of whom were NHL-B(24). However, our findings did not corroborate these results. On the other hand, a high concentration of uric acid at diagnosis was a strong predictor of adverse outcome in our patients. Therefore, tumor lysis syndrome also occurs prior to starting chemotherapy and uric acid can be another good marker of tumor burden. In this study, 12 patients (26.7%) died, a very similar situation to that reported for African children (23.8%)(25). However, this rate is much higher than that recorded in developed countries, which is around 2.8%(15). The higher mortality rate for patients treated in low-income countries may be due to a lack of supportive care required by the chemotherapy scheme employed. Another problem is malnutrition. These children are probably at increased risk for therapy-related toxicity, including life- threatening infections(26). In the present cohort of patients, one third had malnutrition at admission, a rate similar to that reported among African children with BL (38.6%)(25). In most treatment regimens currently used for childhood and adolescent B-NHL the key component is HD-MTX in both developed(8,9) and developing countries(27). However, dose and administration schedules vary considerably. Some low-income countries such as Brazil, Argentina, Lebanon and Iraq have reported improved survival rates of children with B-NHL, although the MTX dose did not exceed 2 g/m2(17,18,28). The present study demonstrates that it is possible to obtain satisfactory results Rev Bras Hematol Hemoter. 2012;34(5):361-6