Diagnosis of retinoblastoma in a presymptomatic stage after detection of interstitial chromosomal deletion 13q.
In a newborn with only minor malformations the finding of an extended interstitial chromosome deletion 13q was unexpectedly found [46,XY,del(13) (q14.11q22.2)]. The included deletion of chromosome band 13q14, which is known to be predisposing for retinoblastoma (Rb), gave rise to subsequent ophthalmological inspection. A multifocal tumor was detected immediately in the right eye and 11 months later contralaterally. In contrast to the Knudson hypothesis, which suggests a high risk of a multifocal and bilateral tumor in patients with an inherited mutation of the RB-1 gene, literature data indicate a reduced tumorigenesis in patients with a cytogenetic deletion of the critical Rb region of chromosome 13. However, the authors' patient shows that even with a cytogenetic deletion early, bilateral, and multifocal tumor formation is possible. Reliable risk estimates of tumorigenesis for patients with a chromosome deletion cannot be given, since most of these were ascertained by their tumor.
Abteilung Klinische Genetik der Universität Ulm, Germany.
I
I
Kennerknecht
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G
Barbi
J
J
Greher
D002872:Chromosome Deletion; D002882:Chromosomes, Human, Pair 13; D005134:Eye Neoplasms / Q000175:diagnosis* / Q000235:genetics; D005145:Face / Q000002:abnormalities; D016161:Genes, Retinoblastoma / Q000235:genetics; D006801:Humans; D007223:Infant; D007621:Karyotyping; D008297:Male; D009367:Neoplasm Staging; D012175:Retinoblastoma / Q000175:diagnosis* / Q000235:genetics