What Causes Retinoblastoma, and How Is It Treated?

The retina is a thin layer of light-sensitive tissue that lines the back of your eye. It’s responsible for capturing light, transforming it into neural signals, and sending these signals to your brain as images.

During development, there are cells called retinoblasts that mature into nerve cells of the retina. But if some of these cells grow out of control, they can form retinoblastoma. Retinoblastoma occurs when nerve cells (neurons) that create the retina undergo genetic mutations.

During the early stages of a child’s development, retinal neurons divide and grow very quickly until they eventually stop. However, if a child has these genetic mutations, retinal neurons continue to grow and divide out of control and eventually form a tumor.

Because the neurons of babies and toddlers grow so quickly, these ages are at the highest risk for developing retinoblastoma. In fact, the average age of children diagnosed with retinoblastoma is 2, and it rarely occurs after 6 years of age.

There are two types of retinoblastoma: inheritable and sporadic. They have different causes. Let’s look at each one in more detail.

Inheritable retinoblastoma

Inheritable retinoblastoma accounts for about one-third of all retinoblastoma cases. In this type, all cells in a child’s body carry cancer mutations, not just their retinal cells.

In most cases, a child acquired these mutations very early in their development, but sometimes they inherit them from one of their parents. This type of retinoblastoma most commonly affects both eyes (bilateral retinoblastoma).

If you carry the gene that can cause retinoblastoma, there’s a chance that you’ll pass it down to your children.

That’s why it’s very important to speak with a genetic counselor if you’ve ever been diagnosed with this condition and plan to start a family.

Sporadic retinoblastoma

In the remaining two-thirds of retinoblastoma cases, a child will not have retinoblastoma mutations in all cells of their body. Instead, their cancer first starts when one retinal neuron in one of their eyes develops a mutation that makes it divide uncontrollably.

Sporadic retinoblastoma can’t be passed down to your children.

Whether a child’s retinoblastoma is inheritable or sporadic, it’s unclear what triggers the genetic mutations. There are no known risk factors for this disease, so it’s important to remember that there is nothing you could have done to prevent your child’s disease.

However, if there’s a family history of retinoblastoma, a child needs to be screened early.

Because retinoblastoma most often affects babies and toddlers, its symptoms aren’t always apparent. Some of the signs you may notice in your child include:

• leukocoria, which is a white reflex that appears when a light shines into the pupil (instead of the typical red reflex) or a white mass behind one or both pupils, often seen when a flash photograph is taken
• strabismus, or eyes looking in different directions (crossed eyes)
• eye redness and puffiness
• nystagmus, or repetitive uncontrolled eye movements
• poor vision

There can be other symptoms, but they are usually less common.

Make an appointment with your child’s pediatrician if you see any of these symptoms or any other changes in one or both of your child’s eyes that concern you.

Treatment of retinoblastoma is tailored to each person. It depends on several factors, including:

• size of the tumor
• location of the tumor
• whether one or both eyes are affected
• tumor stage and whether it’s spread to other tissues outside of the eye (metastasis)
• age and overall health

Therapies for retinoblastoma include:

• chemotherapy
• cryotherapy, or cold treatment
• laser therapy
• radiation therapy
• enucleation, or surgery to remove the affected eye

Sometimes, doctors can combine these treatments to achieve the best results.

If retinoblastoma is only in one eye, treatment depends on whether vision in the eye can be saved. If the tumor is in both eyes, doctors will try to save at least one eye if possible so that some vision can be maintained.

The goals of retinoblastoma treatment are:

• to save the child’s life
• to cure the cancer
• to save the eye, if possible
• to preserve as much vision as possible
• to limit the risk of side effects caused by treatment, especially radiation therapy, as it may increase the risk of developing another type of cancer later in a child’s life

The good news is that more than 9 out of 10 children with retinoblastoma are cured. The chances of long-term survival are much better if the cancer hasn’t spread to other tissues outside the eye.

The 5-year survival in children with retinoblastoma is 96 percent. This means that, on average, 96 percent of kids diagnosed with retinoblastoma live at least 5 years after their diagnosis.

The outlook for this cancer is very individual and depends on several factors, such as:

• overall health
• whether retinoblastoma is sporadic or inheritable
• the cancer stage
• treatments used
• how the tumor responds to treatment

Retinoblastoma is a rare type of eye cancer that affects the retina at the back of the eye. It’s most common in babies and toddlers.

Retinoblastoma occurs when retina cells develop mutations that cause them to divide uncontrollably. There are two types of retinoblastoma: inheritable (found in all cells in the body) and sporadic (found only in retinal cells).

The most common symptom of retinoblastoma is leukocoria, a white mass behind the pupil, but there are other symptoms. Retinoblastoma is almost always curable, but it’s important to diagnose it early for the best outcome.