Molecular and epidemiologic findings of childhood acute leukemia in Costa Rica.
In Central America, nearly 70% of pediatric cancer is related to hemato-oncologic disorders, especially acute lymphoblastic leukemia (ALL). Preliminary studies have described a high incidence of childhood leukemia in these countries; however, no molecular analyses of these malignancies have yet been carried out. We studied diagnostic samples from 84 patients from the National Children's Hospital in San Jose, Costa Rica (65 precursor B-ALL, 5 T-cell ALL, and 14 acute myeloblastic leukemia). Our methodology included cytogenetic, fluorescent in situ hybridization, and polymerase chain reaction approaches. The observed rate of leukemia was 52.2 cases per million children per year. Twelve out of 65 (18.4%) precursor B-ALL tested positive for TEL-AML1 and 3 cases for BCR-ABL (4.6%). In addition, we detected 2 patients carrying an E2A-PBX1 transcript (3.1%) and 1 patient with an MLL-AF4 fusion gene (1.5%). None of the T-cell ALL cases were positive for either SIL-TAL1 or HOX11L2. Within 14 acute myeloblastic leukemia patients, we confirmed 2 cases with FLT3-internal tandem duplication+, 1 patient with AML1-ETO, and only 1 case carrying a PML-RARalpha rearrangement. The present study confirms the relatively high incidence of pediatric leukemia in Costa Rica and constitutes the first report regarding the incidence of the main molecular alterations of childhood leukemia in our region.
Santamaría-Quesada
Carlos
C
Clinical Laboratory Department, Molecular Biology Laboratory double, National Children's Hospital, San José, Costa Rica. csantamariaq@hnn.sa.cr
Vargas
Mario
M
Venegas
Patricia
P
Calvo
Melvin
M
Obando
Catalina
C
Valverde
Berta
B
Cartín
Walter
W
Carrillo
Juan Manuel
JM
Jimenez
Rafael
R
González
Marcos
M
D000208:Acute Disease; D002648:Child; D003364:Costa Rica / Q000453:epidemiology; D020732:Cytogenetic Analysis; D015321:Gene Rearrangement; D006801:Humans; D007938:Leukemia / Q000175:diagnosis / Q000453:epidemiology* / Q000235:genetics*; D009154:Mutation; D015514:Oncogene Proteins, Fusion / Q000032:analysis
D015514:Oncogene Proteins, Fusion