RESUMEN
Anaplastic large cell lymphoma, ALK-positive is a mature T-cell neoplasm that accounts for 10- 20% of paediatric non-Hodgkin lymphoma. Its frequency in infants and very young children is exceedingly rare and was rarely documented in the literature. The disease prognosis in this agegroup is unknown. We report two male patients who were diagnosed with ALCL-ALK(+) at the ages of 12 and 14 months, both presented with fever and leukemoid reaction, one was in stage I and the other in stage IV diseases. They were treated with APO-based chemotherapy and remained in complete remission for more than 7 years. To our knowledge, this is the first report that describes the long-term survival of ALCL-ALK(+) at very young age.
Asunto(s)
Linfoma Anaplásico de Células Grandes , Proteínas Tirosina Quinasas Receptoras , Lactante , Humanos , Masculino , Niño , Preescolar , Quinasa de Linfoma Anaplásico/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/uso terapéutico , Linfoma Anaplásico de Células Grandes/diagnóstico , Linfoma Anaplásico de Células Grandes/patología , Estudios de Seguimiento , PronósticoRESUMEN
BACKGROUND: Weak D phenotypes involve a quantitative variation of D. The genomic basis in weak D has been disputed, however. STUDY DESIGN AND METHODS: Five sequence-specific polymerase chain reactions (SSP-PCRs) on exons 2, 5, and 7 of the RHD gene were evaluated in 248 white and 98 Japanese blood donors and compared with the results obtained by amplification of intron 4 and serology. All methods and SSP-PCR testing on the 3' non-coding region of the RHD gene were applied to the genotyping of 94 DNA samples derived from individuals expressing weak D phenotypes. RESULTS: Concordant results were obtained with all genotyping and phenotyping methods in testing 201 D-positive and 145 D-negative donors. Four of 94 weak D samples were typed as D-negative by amplification of intron 4 and SSP-PCR on exon 5. Phenotyping with monoclonal antibodies revealed a DVI category in one of these cases and DFR phenotype in three of these cases. One weak D sample, which reacted like normal D-positive cells with all applied monoclonal antibodies, was typed falsely negative by SSP-PCR on exon 5 because of a point mutation at nucleotide 667 (T-->G) that resulted in a Phe223Val amino acid substitution. In this individual, heterozygosity was found at two other amino acid positions (Glu233Gln and Val238Met) by restriction fragment length polymorphism analysis. CONCLUSION: Genetic diversity in weak D phenotypes is rare. Only 1 of 90 true weak D phenotypes (1.1%) had a genetic variation in testing on seven gene regions of the RHD gene.
