How should childhood acute lymphoblastic leukemia relapses in low-income and middle-income countries be managed: The AHOPCA-ALL study group experience.

BACKGROUND: Children with relapsed acute lymphoblastic leukemia (ALL) in low-income and middle-income countries rarely survive. The Pediatric Hematology-Oncology Association of Central America (AHOPCA) developed the AHOPCA-ALL REC 2014 protocol to improve outcomes in resource-constrained settings without access to stem cell transplantation. METHODS: The AHOPCA-ALL REC 2014 protocol was based on a modified frontline induction phase 1A, a consolidation therapy with six modified R-blocks derived from the ALL-Berlin-Frankfurt-Munster REZ 2002 protocol and intermittent maintenance therapy. Children with B-lineage ALL were eligible after a late medullary relapse, an early or late combined relapse, or any extramedullary relapses. Those with T-lineage ALL were eligible after early and late extramedullary relapses, as were those with both B-lineage and T-lineage relapses occurring at least 3 months after therapy abandonment. RESULTS: The study population included 190 patients with T-lineage (n = 3) and B-lineage (n = 187) ALL. Of those with B-lineage ALL, 25 patients had a very early extramedullary relapse, 40 had an early relapse (32 extramedullary and 8 combined), and 125 had a late relapse (34 extramedullary, 19 combined, and 72 medullary). The main cause of treatment failure was second relapse (52.1%). The 3-year event-free survival rate (± standard error) was 25.9% ± 3.5%, and the 3-year overall survival rate was 36.7% ± 3.8%. The 3-year event-free survival rate was 47.2% ± 4.7% for late relapses. The most frequently reported toxicity was grade 3 or 4 infection. Mortality during treatment occurred in 17 patients (8.9%), in most cases because of infectious complications. CONCLUSIONS: Selected children with relapsed ALL in Central America can be cured with second-line regimens even without access to consolidation with stem cell transplantation. Children in low-income and middle-income countries who have lower risk relapses of ALL should be treated with curative intent.

Asociación de Hemato-Oncología Pediátrica de Centro América (AHOPCA): a model for sustainable development in pediatric oncology.

Bridging the survival gap for children with cancer, between those (the great majority) in low and middle income countries (LMIC) and their economically advantaged counterparts, is a challenge that has been addressed by twinning institutions in high income countries with centers in LMIC. The long-established partnership between a Central American consortium--Asociación de Hemato-Oncología Pediátrica de Centro América (AHOPCA)--and institutions in Europe and North America provides a striking example of such a twinning program. The demonstrable success of this endeavor offers a model for improving the health outcomes of children with cancer worldwide. As this remarkable enterprise celebrates its 15th anniversary, it is appropriate to reflect on its origin, subsequent growth and development, and the lessons it provides for others embarking on or already engaged in similar journeys. Many challenges have been encountered and not all yet overcome. Commitment to the endeavor, collaboration in its achievements and determination to overcome obstacles collectively are the hallmarks that stamp AHOPCA as a particularly successful partnership in advancing pediatric oncology in the developing world.

Nutritional status at diagnosis is related to clinical outcomes in children and adolescents with cancer: a perspective from Central America.

BACKGROUND: The prevalence of malnutrition in children may exceed 50% in countries with limited resources. The aims of this study were to assess nutritional status at diagnosis in children and adolescents with cancer, and to correlate it with clinical outcomes in the Spanish speaking countries of Central America that formed the AHOPCA (Asociacion de Hemato-Oncologia Pediatrica de Centro America) consortium. METHODS: Patients aged 1-18 years, diagnosed with cancer between 1st October 2004 and 30th September 2007, were eligible for study. Weight (kg) and height or length (m), mid upper arm circumference--MUAC and triceps skin fold thickness--TSFT were measured and their Z-scores or percentiles were calculated. Three categories of nutritional status were defined according to these parameters. RESULTS: A total of 2954 new patients were enrolled; 1787 had all anthropometric measurements performed and 1513 also had measurements of serum albumin. By arm anthropometry 322/1787 patients (18%) had moderate nutritional depletion and 813/1787 patients (45%) were severely depleted. Adding serum albumin, the proportion classified as severely depleted rose to 59%. Malnourished children more often abandoned therapy and their event free survival was inferior to that of other children. CONCLUSIONS: Arm anthropometry in children with cancer is a sensitive measure of nutritional status. Since malnutrition at diagnosis was related to important clinical outcomes, an opportunity exists to devise simple, cost-effective nutritional interventions in such children that may enhance their prospects for survival.

Hemoglobinas anormales en la población neonatal de Costa Rica

Abnormal haemoglobins in the newborn human population of Costa Rica. Hemoglobinopathies are hereditary autosomic recessive diseases. A total of 70 943 samples of whole blood collected by heel prick in filter paper (S&S 903) from throughout Costa Rica (October 2005-October 2006) were analyzed to detect variants of hemoglobin by the iso-electric focusing technique. Eight hundred ninety one cases presented some variant, for a frecuency of 1/79. Five cases are homozygous for hemoglobin S (sickle cell disease) and one shows the double heterozygous genotype SC. in this study the S and C variants of hemoglobin, although with some local differences, are widespread all over the country. Thus, the prevention of new cases is important through the testing of hemoglobin in the Costa Rican National Newborn Screening Program, together with a interdisciplinary National Program of Education for the disease and carrier status (AS/AC) for patients, families and medicar personnel. This is the basis for proper genetic counseling, to improve treatment and to reduce morbi-mortality. Rev. Biol. Trop. 56 (3): 995-1001. Epub 2008 September 30.

Se han analizado un total de 70 943 muestras de sangre total en papel filtro S&S 903 de neonatos de Costa Rica (octubre 2005 a Octubre 2006) con el fin de detectar variantes de hemoglobina mediante la técnica de isoelectroenfoque. Se detectaron 891 casos con alguna variante para una frecuencia de 1/79. Se clasifican 5 casos homocigotos para hemoglobina S (anemia drepanocítica o anemia falciforme) y un caso doble heterocigoto para SC. En este estudio se demuestra que las variantes fenotípicas de hemoglobina S como la C, se encuentran distribuidas por todo el país con algunas diferencias locales, razón por la cual es importante que la prevención de nuevos casos se realicé a través de nuestro Programa Nacional de Tamizaje de Hemoglobinas junto con un Programa Nacional interdisciplinario de Educación para el portador del rasgo (AS/AC) como, para el enfermo y su familia; al igual que la instauración de programas dirigidos a médicos generales y enfermeras en todas las regiones de salud del país, para asegurar consejo genético a portadores y enfermos, y a la vez, mejorar los sistemas de tratamiento a los pacientes para reducir la morbi -mortalidad.

[Abnormal haemoglobins in the newborn human population of Costa Rica]. / Hemoglobinas anormales en la población neonatal de Costa Rica.

Hemoglobinopathies are hereditary autosomic recessive diseases. A total of 70 943 samples of whole blood collected by heel prick in filter paper (S&S 903) from throughout Costa Rica (October 2005-October 2006) were analyzed to detect variants of hemoglobin by the iso-electric focusing technique. Eight hundred ninety one cases presented some variant, for a frecuency of 1/79. Five cases are homozygous for hemoglobin S (sickle cell disease) and one shows the double heterozygous genotype SC. In this study the S and C variants of hemoglobin, although with some local differences, are widespread all over the country. Thus, the prevention of new cases is important through the testing of hemoglobin in the Costa Rican National Newborn Screening Program, together with a Interdisciplinary National Program of Education for the disease and carrier status (AS/AC) for patients, families and medicar personnel. This is the basis for proper genetic counseling, to improve treatment and to reduce morbi-mortality.

Citogenética y citoquímica de pacientes con leucemias en dos hospitales neotropicales / Citogenetics and citochemistry of leukemia patients in two neotropical hospitals

A cytogenetic and/or cytochemical study was performed in 166 individuals with leukemia or related disorders, in two major Costa Rican hospitals. In those patients treated at an adult`s (14 years old and over), acute leukemias represented 66 porcent of all cases. In that hospital the most frequent types of disorders were, in decreasing order: ANLL(>M1), ALL, CML (all of them showed the Ph chromosome) and MDS. In the cases fron a children`s hospital (<14 years old) acute leukemias were 98 porcent. Among them the order of frequency was: ALL (70 porcent): ALL-1(84 porcent), ALL-2(16 porcent) and ANLL (27 porcent): M5a>M3>M4>M5b. In ALL 85 porcent were type B and occurred mostly in women while 15 porcent of them were type T and more frequent in males. There was 5.6 porcent infant leukemia, which presented a similar number of acute lymphoids and myeloids. The cytogenetic pattern was similar among Costa Rica and other tropical and temperate countries. Key words: Leukemia cytogenetics, acute lymphocytic leukemia, acute nonlymphocitic leukemia, chronic granulocytic leukemia

Evaluación de parámetros plaquetarios en trombocitosis pediátrica / Evaluation of parametrics platelet in pediatric thrombocytosis

El hallazgo de un recuento plaquetario elevado tiene importantes implicaciones para el diagnóstico, pronóstico y tratamiento del paciente. En el presente estudio, se pudo comprobar la utilidad de los índices plaquetarios como el VPM, (volumen plaquetar medio ) y el PDW (rango de la distribución plaquearia), en unión del cómputo de plaquetas, para el diagnóstico de trombocitosis reactiva en pacientes pediátricos. Un 45 por ciento de los pacientes estudiados presentaron alteraciones en el VPM, en el PDW o en ambos, en comparacón con los valores que se obtuvieron en el grupo control. Se observó en que los niños con trombocitosis reactiva, tendían a presentar plaquetas de menor tamaño y con mayor heterogeneidadd. Es importante considerar estos parámetros disponibles actualmente, como una orientación diagnóstica de primera línea para las trombocitosis. (Rev Cost Cienc Med 1999; 20(3,4): 185-191) Palabras claves: plaquetas, volumen plaquetar, heterogeneidad plaquetaria, trombocitosis