Retinoblastoma is a malignant tumour that originates from embryonic retinal cells. It is the most common intra-ocular cancer of infants with a frequency of 1 in 18000 live births. Early genetic diagnosis and focal treatment, while lesions can still be ablated, is central to an effective management strategy. Inheritance of a mutation in one copy of the RB1 gene leads to a hereditary predisposition to retinoblastoma. Tumour development is initiated when a mutation of the second allele occurs. Somatic RB1 mutations in embryonal retinal tissue lead to non-hereditary unilateral retinoblastomas from a solitary focus. However, some unilateral tumours are the result of inherited mutations that confer risk to the affected individual with a risk of subsequent malignancy. Germline mutations generally result in bilateral disease and/or multiple tumours. There is a 3% risk of an associated intracranial retinoblastoma and a high risk (6-35%) of a second non-ocular malignancy later in life, especially when external beam radiotherapy is used for ocular treatment.
Genetics - Molecular Pathology
MOLP
intra-ocular cancer
4 weeks
7312