Retinoblastoma (Rb)





Retinoblastoma (Rb) is a malignant congenital tumor that develops in the retina. It forms on the immature cells of the light-sensitive lining of nerves at the back of one or both eyes.

This condition has two forms: heritable and non-heritable. A little more than half of the diagnosed cases are of the non-heritable form, meaning it cannot be transmitted to their offspring (although cancers are often considered as genetic). If there is no prior history of the condition in the family, the case is considered as sporadic, but it doesn’t mean that it shall be non-heritable. Most heritable Rb’s are unilateral (affects only one eye), while non-heritable Rb’s are most likely bilateral (both eyes are affected). Unilateral retinoblastomas occur twice as often as bilateral retinoblastomas.

Retinoblastoma is a rare condition. It affects more or less 11 in a million children who are below 5 years old, or roughly 1 in 18,000 live births in the United States. Despite that, retinoblastoma is considered as the most common pediatric cancerous tumor of the eye. Roughly 80% of retinoblastoma diagnoses are on children who are below 3 years old, and diagnosis beyond the sixth year are already quite rare.



A mutation on the RB1 gene on chromosome 13 causes the retinoblastoma of the heritable genetic form. This defective gene has a 50% chance of being acquired by a child if one parent has it, however, it does necessarily mean that he or she will be manifesting cancer during fetal development or in his or her early childhood years.

The condition occurs when the nerve cells of the retina begins to undergo genetic mutation. The mutations make the cells grow and multiply even when it is supposed to simply just mature then die out. These cells then form into a tumor. The mutated cells of a retinoblastoma, however, sometimes will spread into the eye and the other structures near it; and can even extend as far as the brain and the spinal cord.


Signs and Symptoms

The following are the general signs of retinoblastoma:

  • Swelling/puffiness and/or redness of the eye;
  • Eyes that seem to go in different directions (lazy eye or amblyopia); and
  • Absence of the customary red-orange reflection (instead, a white spot is in place) from the center of the eyes when a light is shined into it, such as when taking pictures with flash.



The treatment for retinoblastoma depends on the size, location, and number of tumors within the retina of the eye. The metastasis of the mutated cells is also considered, including the locations of the spread.

Several treatment options can be chosen from to manage retinoblastoma:

  • Chemotherapy;
  • Radiation Therapy;
  • Laser Therapy (Photocoagulation);
  • Cryotherapy (Cold Treatments);
  • Thermotherapy (Heat Treatments); and
  • Surgery.


Disability Tax Credits for Retinoblastoma

Retinoblastoma affects an individual beginning the early days of his or her life. Presence of these tumors in the eyes can seriously affect the vision of the affected person. However, prognosis for this type of condition can be good, especially when it has been managed early. Even with this, a diagnosis of retinoblastoma in a child can entitle him or her to a lifetime disability savings plan worth up to $90,000 in government grants and bonds from the Canadian Revenue Agency. To know more about this, dial the HandyTax hotline and ask for an agent who can assist you with your needs.