Strong inflammatory response and Th1-polarization profile in children with acute lymphoblastic leukemia without apparent infection.

Children with acute lymphoblastic leukemia (ALL) often present fever. Febrile states are usually associated with infectious processes that generate an inflammatory response involving various molecules, including cytokines. However, an inflammatory response may also occur in the absence of infection. We hypothesized that the levels of inflammatory cytokines are increased in children with ALL without apparent infection. The serum levels of 13 cytokines in 99 patients with ALL and 48 non-oncological patients without apparent infection were measured using multiplex analyte profiling technology (Luminex®). The concentration of circulating pro-inflammatory cytokines associated with fever was similar between patients with ALL and fever at diagnosis and those without fever. The levels of tumor necrosis factor α, interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 (MCP-1) and IL-10 were higher in patients with ALL vs. the control group (P<0.05). Moreover, the levels of the T helper 1 (interferon­Î³ and IL-12) cytokines were higher in patients with ALL vs. the control group. Transforming growth factor ß was lower in patients with ALL vs. the control group (P<0.05). The levels of IL-1ß, IL-2, IL-4, IL-13, and IL-17 were similar in the two groups. Our results indicate that the circulating levels of seven of the important studied cytokines are elevated in patients with newly diagnosed ALL without apparent infection, reflecting a strong and deregulated inflammatory state in this disease, with a Th1-polarization profile.

Allergy and acute leukaemia in children with Down syndrome: a population study. Report from the Mexican inter-institutional group for the identification of the causes of childhood leukaemia.

BACKGROUND: Allergies have been described as protective factors against the development of childhood acute leukaemia (AL). Our objective was to investigate the associations between allergy history and the development of AL and acute lymphoblastic leukaemia (ALL) in children with Down syndrome (DS). METHODS: A case-control study was performed in Mexico City. The cases (n=97) were diagnosed at nine public hospitals, and the controls (n=222) were recruited at institutions for children with DS. Odds ratios (OR) were calculated. RESULTS: Asthma was positively associated with AL development (OR=4.18; 95% confidence interval (CI): 1.47-11.87), whereas skin allergies were negatively associated (OR=0.42; 95% CI: 0.20-0.91). CONCLUSION: Our findings suggest that allergies and AL in children with DS share biological and immune mechanisms. To our knowledge, this is the first study reporting associations between allergies and AL in children with DS.

Breastfeeding and early infection in the aetiology of childhood leukaemia in Down syndrome.

BACKGROUND: For a child to develop acute leukaemia (AL), environmental exposure may not be sufficient: interaction with a susceptibility factor to the disease, such as Down syndrome (DS), may also be necessary. We assessed whether breastfeeding and early infection were associated with the risk of developing AL in children with DS. METHODS: Children with DS in Mexico City, and either with or without AL, were the cases (N=57) and controls (N=218), respectively. Population was divided in children with AL and with acute lymphoblastic leukaemia (ALL) and also in children < or = 6 and >6 years old. RESULTS: Breastfeeding and early infections showed moderate (but not significant) association for AL, whereas hospitalisation by infection during the first year of life increased the risk: odds ratios (confidence interval 95%) were 0.84 (0.43-1.61), 1.70 (0.82-3.52); and 3.57 (1.59-8.05), respectively. A similar result was obtained when only ALL was analysed. CONCLUSION: We found that breastfeeding was a protective factor for developing AL and ALL, and during the first year of life, infections requiring hospitalisation were related to a risk for developing the disease in those children with DS >6 years of age. These data do not support the Greaves's hypothesis of early infection being protective for developing ALL.

A multicentre report from the Mexican Retinoblastoma Group.

BACKGROUND: Retinoblastoma (RB) is a relatively uncommon tumour in childhood. The incidence of retinoblastoma in Mexico is probably higher than the incidence reported worldwide, however there is not enough information about the characteristics of this illness in Mexico. This report aims to present the results of a multicentre clinical survey of RB in Mexico. METHODS: A retrospective study was carried out on all RB cases treated in 16 institutions during the last six years. The variables analysed were age at diagnosis, sex, affected eyes, treatment modalities, and pathological staging. Overall survival was obtained. RESULTS: The authors analysed 500 cases; age range was 0-182 months. There were 364 unilateral cases (72.8%). Enucleation was performed in 84.9% of the patients. The St Jude's staging was: 7.4% stage I, 52.8% stage II, 18.0% stage III, 11.4% stage IV, 7.2% not evaluated, and 3.2% missing data. Chemotherapy was used in 74.4% of the patients. Disease free survival was 89% at 73 months follow up. CONCLUSIONS: The paper presents a great number of cases and pioneers multicentre studies in paediatric ophthalmology and oncology in this country. Given the great number of patients in advanced stages and the variability on treatment schemes, it is evident that it is mandatory to work in a cooperative group and develop a national early detection programme as well as a treatment protocol which include all specialists involved in the care of patients with RB.

Pediatric oncology at Hospital Infantil de Mexico: fifty-five years of accomplishment.

The Department of Oncology at Hospital Infantil de México Federico Gómez (HIMFG) was the first unit in our country, and one of the first in Latin America, to specialize in the management of children with cancer. The HIMFG is part of the National Institutes of Health of Mexico, and is a reference hospital with research, educative, and tertiary care medical function. To date, the HIMFG and the Instituto Nacional de Pediatria are the principal medical centers in which children with cancer receive comprehensive care.

Diagnosis of bone marrow metastases in children with solid tumors and lymphomas. Aspiration, or unilateral or bilateral biopsy?

BACKGROUND: Malignancies are among the most common causes of death in children. The present study was undertaken to evaluate and compare bone marrow aspiration and unilateral biopsy to detect bone marrow metastases in pediatric patients, using bilateral biopsy as the gold standard. METHODS: During a 6-month period, 63 consecutive newly diagnosed children with confirmed malignant diseases other than leukemia were evaluated for bone marrow metastases or infiltration. Biopsies were obtained from both right and left posterior iliac crests whereas aspiration was performed only at the right crest. Interpretation to the right-side biopsy was considered as the unilateral biopsy result, whereas the bilateral biopsy result was as follows: positively was accepted if one or both of the two-side samples were qualified as positive, while a negative result was considered only if both sides were negative. The bilateral biopsy was considered the gold standard, and sensitivity, specificity, positive and negative predictive value, and false positive and negative rates were computed for the unilateral biopsy and aspiration procedure. RESULTS: We identified bone marrow metastases in 11 (17.5%) patients. The sensitivity was the only significant difference (p <0.05) observed between unilateral biopsy and aspiration. Finally, of the 63 patients, unilateral biopsy was reported as inadequate in one patient (1.6%), while aspiration was inadequate in two (3.2%). CONCLUSION: Unilateral biopsy was better than bone marrow aspiration. However, because bilateral biopsy is the gold standard, we recommend using this and bone marrow aspiration simultaneously to evaluate a pediatric patient with any malignancy potentially infiltrating bone marrow.