Retinoblastoma risk factors

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Simrat Sarai, M.D. [2] Sahar Memar Montazerin, M.D.[3]

Risk factors associated with the development of retinoblastoma are mutation in RB1 gene, a positive family history of retinoblastoma, living in areas with high incidence rate of the disease, HPV exposure and other environmental factors.

• Retinoblastoma has been associated with the following genetic disorders:
  • RB1 gene mutation
  • Deletion of chromosome 13 long arm of (13q deletion syndrome)^[1]
  • Fragile-X syndrome

• Approximately 10% of patients with retinoblastoma have a previously established family history of the disease.^[2]
• The magnitude of risk among offsprings of the proband depends upon the tumor presentation in the proband (unilateral or bilateral) and the relationship of the individual to the patient with retinoblastoma.
• The table below provides the estimated risk percentage of developing retinoblastoma in individuals with a positive family history of retinoblastoma:

• The presence of HPV sequences in retinoblastoma tumor tissue may play a role in the development of sporadic retinoblastoma.^[4]
• There is evidence suggesting that the mutations of RB1 are more common during spermatogenesis than oogenesis.^[5]

• Epidemiological data indicates that retinoblastoma has higher incidence in some geographic areas. For more information click here.
• Other factors associated with an increased risk of retinoblastoma development include:^[6]
  • Mother’s use of insect or garden sprays during pregnancy
  • Diagnostic x-ray with direct fetal exposure
  • Father’s employment as a welder, machinist, or related metal worker

​