Retinoblastoma is a rare form of cancer that affects the eyes. It is usually diagnosed in children before the age of 5. Retinoblastoma symptoms can be successfully treated providing they are detected early, and approximately 90% of children make a full recovery.
This article explains key retinoblastoma symptoms and how it is treated. But first, we will look at what retinoblastoma is and its causes.
What is Retinoblastoma?
Retinoblastoma is a cancer of the eye and affects part of the eye called the retina. It is a thin layer of tissue that lines the back of the eye and contains light-sensitive cells. When light shines onto the retina through the pupil, it is converted into nerve signals and sent to the brain.
The retina is one of the first structures to develop when a baby is in the womb. Specialized cells grow and multiply rapidly, then stop once the eye has formed. However, sometimes a genetic mutation means that the cells do not stop growing when they should. This causes a tumor to develop.
The mutation usually occurs in a gene known as RB1. In around 40% of cases, it is inherited from the baby’s parents. In these cases, the mutation tends to occur quite early during development and often affects both eyes.
In the remaining 60% of cases, the mutation occurs spontaneously. This tends to happen later on in the developmental process and usually only affects one eye.
Because retinoblastoma is often inherited, babies born into families with a history of the condition should undergo genetic screening. However, in many cases, there is no known family history. Therefore, it is important to know the symptoms of retinoblastoma, so they can be investigated as soon as possible if they occur.
The 7 Most Common Retinoblastoma Symptoms
1. White Color in the Center of the Eye
The most common retinoblastoma symptom is an unusual white color in the pupil (the center of the eye).
The pupils are openings that allow light to shine into the eye and onto the retina. They usually look dark but under a bright light they can seem red due to the retina’s blood vessels. This is why people’s eyes sometimes appear red in photos taken with a flash.
In retinoblastoma, the pupils will appear white rather than red in photos. They might also be reflective in low or artificial light, much like a cat’s eyes.
This symptom is known as white pupillary reflex and is one of the key diagnostic features of retinoblastoma. It may be noticed by parents or picked up during a routine eye exam, which is why regular check-ups are so important.
2. Other Pupil Changes
In addition to the white pupillary reflex, children with retinoblastoma may have other changes to their pupils.
Normally, the pupils get smaller in bright light to limit the amount of light entering the eye. In retinoblastoma, this may not happen, or the pupils may generally appear larger than usual.
The eyes might also move uncontrollably up and down or from side to side, which is a symptom known as nystagmus.
3. Eye Color Changes
The colored part of the eye is the iris. It is a muscle that controls the size of the pupil and helps to focus light onto the retina.
In retinoblastoma, the iris can change color so that a child has different colored eyes. Alternatively, just one part of the iris may change color.
4. Squint or Lazy Eye
Retinoblastoma can also cause the eyes to look in opposite directions, either toward the nose or the ears. The medical name for this is strabismus but it is commonly known as a lazy eye or squint.
This symptom can occur in children for many different reasons, such as muscle weakness around the eye. However, it should always be investigated in case retinoblastoma is the cause.
5. Red or Swollen Eye
The affected eye may appear red or swollen as a result of inflammation. The eye might seem to be bulging, or there could be blood in the front part of the eye. However, children with retinoblastoma do not usually complain of eye pain.
6. Poor Vision
As a tumor grows larger, pressure can build up inside the eye, affecting one’s vision. Parents or teachers might notice a child having difficulty focusing on faces or objects or controlling their eye movements. Older children might complain that they cannot see as well as they used to.
7. Full-Body Symptoms
Most children with retinoblastoma seem otherwise healthy. However, if the cancer spreads outside the eye, they may experience other symptoms, including:
- Poor appetite.
- Weight loss.
- Swollen glands in the neck.
There are many other possible causes of these symptoms, but they should be investigated by a doctor.
Most cases of retinoblastoma can be treated successfully if detected early enough. The precise treatment will depend upon the location of the tumor and whether it has spread outside the eye.
For small tumors that are contained within the eye (intraocular), local treatment may be sufficient. For example, the cancer cells can be destroyed with extreme heat (thermotherapy) or cold (cryotherapy). Local radiation treatment (brachytherapy) or chemotherapy may also be an option.
If the tumor has grown large and there is no vision, then the eye may have to be removed surgically (enucleation). However, this is a last resort and doctors will do everything they can to save a child’s eyesight if possible.
If the cancer has spread to other parts of the body (extraocular), systemic treatment such as chemotherapy will be necessary. This will usually be given in addition to local treatments for the eye.
Once the cancer has been treated, the child will need to return for regular follow-ups to ensure that it has not returned or spread.