Retinoblastoma: towards an earlier diagnosis. / Retinoblastoma: hacia un diagnóstico más precoz.

OBJECTIVES: The number of enucleations and visual sequels due to retinoblastoma is high. The aim of this study was to evaluate the different diagnostic aspects and propose strategies that might improve the clinical management of this condition. METHOD: A retrospective study was conducted on 38 patients with retinoblastoma studied genetically (29 unilateral, 9 bilateral). The evaluation included: age of onset, clinical signs, and time since onset, number of enucleations, time to diagnosis, and survival at 5 years. RESULTS: Leukocoria was the main clinical sign (present in 90% of cases). The mean diagnostic delay was 3.2 months. Among the unilateral cases, the eyes were enucleated in 76%, and 55% in the bilateral forms. Only one death was found among the 25 patients followed-up for at least 5 years. CONCLUSIONS: Retinoblastoma diagnostic and treatment strategies need to be updated. Good coordination between paediatricians and ophthalmologists is essential for this. Its management in reference centres, which have the necessary technology and experience, should contribute to increase the rate of organ preservation.

Recombinant X chromosome in a prenatal diagnosis.

The prenatal cytogenetic study of an amniotic fluid sample of a 39-year-old female showed one X chromosome with a fragment of extra material in the short arm. The G-band pattern suggested that the extra material could be the long arm of an X chromosome. Several complementary studies were performed in order to better clarify the origin of the material. These studies included parental karyotypes, microsatellite typing and comparative genomic hybridization (CGH). The results obtained allowed us to conclude that the derivative chromosome arose de novo as a recombinant X chromosome with duplication of Xq and partial deletion of Xp. Once informed, the parents decided to continue with the pregnancy, after which a healthy girl was born with no apparent disorders.