TUMOUR BIOLOGY

Le résumé fourni par la source

DIG (Desmoplastic Infantile Ganglioglioma) is a rare intracranial neoplasm classified as WHO grade I tumor under neuronal and mixed neuronal glial tumors (under 2007 World Health Organization brain tumor classification).It is usually considered to have a good prognosis but 40% of the cases require additional medical, radiation and/or further surgical intervention and 15% of infants and children develop leptomeningeal spread or die from DIG.We report a case of DIG presenting at 2 mo of age that showed aggressive behavior, requiring debulking at 2.5 mo age and subsequently at 10 mo age following a tumor recurrence.Chemotherapy following surgery was successful in suppressing the tumor growth for 7.5 yrs.He then presented with malignant transformation into glioblastoma.Successful debulking followed by chemotherapy was given.At 1 yr follow up, the child had moderate neurological deficits but had a subsequent rapid progression and died.Chromosome microarray analysis (CMA) using oligo array performed on the biopsy specimen obtained at 2 mo age did not show any significant abnormality.However, CMA of the glioblastoma was very abnormal showing significant genomic deletions and duplications.Genomic next generation sequencing showed a somatic single nucleotide non-synonymous variant, p.R248Q in Exon 7 of TP53 in the primary DIG and the GBM tumors.The non-synonymous variant in TP53 gene is predicted to be deleterious, altering the structure of the L2/L3 motif of the DNA binding domain tp53 protein.The TP53 gene which is a known primary site of genetic alteration that predisposes to malignant tumors provides a reason for the transformation of DIG to glioblastoma in our case.Therefore, molecular genetic testing is recommended on some DIG tumors which may provide a prognostic biological marker. TB-002.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.