Retinoblastoma is a cancer that begins in the retina — the sensitive lining on the inside of your eye. Retinoblastoma most commonly affects young children, but can rarely occur in adults.
Your retina is comprised of nerve tissue that senses light as it comes through the front of your eye. The retina sends signals through your optic nerve to your brain, where these signals are interpreted as images.
Although a rare form of cancer, retinoblastoma is the most common cancer affecting the eye in children. The National Cancer Institute estimates about 300 children are diagnosed with retinoblastoma each year in the United States.
Signs of retinoblastoma include:
When to see a doctor
Make an appointment with your child's doctor if you notice any changes to your child's eyes that concern you. Retinoblastoma is a rare cancer, so your child's doctor may explore other more common eye conditions first.
If you have a family history of retinoblastoma, ask your pediatrician when your child should begin regular eye exams to screen for retinoblastoma.
Retinoblastoma occurs when nerve cells in the retina develop genetic mutations that cause them to continue growing and multiplying when healthy cells would die. This accumulating mass of cells forms a tumor. Retinoblastoma cells can invade further into the eye and nearby structures. Retinoblastoma can also spread (metastasize) to other areas of the body, including the brain and spine.
In the majority of cases, it's not clear what causes the genetic mutations that lead to retinoblastoma. However, it's possible for children to inherit a genetic mutation from their parents.
Inherited retinoblastoma
Gene mutations that increase the risk of retinoblastoma and other cancers can be passed from parents to children. Inherited retinoblastoma is passed from parents to children in an autosomal dominant pattern, which means only one parent needs a single copy of the mutated gene in order to pass the increased risk of retinoblastoma on to the children. If one parent carries a mutated gene, each child has a 50 percent chance of inheriting that gene.
Although a genetic mutation increases a child's risk of retinoblastoma, it doesn't mean that cancer is inevitable.
Children with the inherited form of retinoblastoma tend to develop the disease at an earlier age. Inherited retinoblastoma also tends to occur in both eyes, as opposed to just one eye.
Long-term side effects of cancer treatment
Treatments for retinoblastoma may cause long-lasting side effects in young children. What long-term side effects your child is at risk of will depend on what treatments are used.
Ask your child's doctor what long-term complications could occur in your child and what signs and symptoms to watch for. In some cases, doctors can predict what health problems your child may be at risk of in the future. In other cases, treatments are relatively new and doctors don't yet know what the long-term risks will be.
Recurrent retinoblastoma
Children treated for retinoblastoma have a risk of cancer returning in and around the treated eye. For this reason, your child's doctor will schedule follow-up exams to check for recurrent retinoblastoma. The doctor will design a personalized follow-up exam schedule for your child. In most cases, this will likely involve eye exams every few months for the first few years after retinoblastoma treatment ends.
Additionally, children with the inherited form of retinoblastoma have an increased risk of developing other types of cancers in any part of the body in the years after treatment. For this reason, children with inherited retinoblastoma require long-term follow-up with a cancer doctor (oncologist).
You're likely to start by first seeing your family doctor or a pediatrician. However, in some cases when you call to set up an appointment, you may be referred immediately to a doctor who specializes in treating eye diseases (ophthalmologist).
Because appointments can be brief, and because there's often a lot of ground to cover, it's a good idea to be well prepared for your child's appointment. Here's some information to help you get ready for your child's appointment, and what to expect from your child's doctor.
What you can do
Your time with your child's doctor is limited, so preparing a list of questions ahead of time will help you make the most of the time. List your questions from most important to least important in case time runs out. For retinoblastoma, some basic questions to ask your child's doctor include:
In addition to the questions that you've prepared to ask your child's doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your child's doctor
Your child's doctor is likely to ask you a number of questions. Being ready to answer them may allow more time to cover other points. Your child's doctor may ask:
What you can do in the meantime
Try to keep your child comfortable by avoiding things that seem to worsen signs and symptoms. Not feeling well and an approaching trip to the doctor may make your child feel anxious. To reduce your child's anxiety, try to:
Tests and procedures used to diagnose retinoblastoma include:
What treatments are best for your child's retinoblastoma depends on the size and location of the tumor, whether cancer has spread to areas other than the eye, your child's overall health and your own preferences. When possible, your child's doctor will work to preserve your child's vision.
Chemotherapy
Chemotherapy is a drug treatment that uses chemicals to kill cancer cells. Chemotherapy can be taken in pill form, or it can be delivered through a vein. Chemotherapy drugs travel throughout the body to kill cancer cells.
In children with retinoblastoma, chemotherapy may help shrink a tumor so another treatment, such as brachytherapy, cryotherapy, thermotherapy or laser therapy, may be used to treat the remaining cancer cells. This may improve the chances that the child won't need surgery.
Chemotherapy may also be used to treat retinoblastoma that has spread to tissues outside the eyeball or to other areas of the body.
Radiation therapy
Radiation therapy uses high-energy beams, such as X-rays and others, to kill cancer cells. Two types of radiation therapy used in treating retinoblastoma include:
Laser therapy (laser photocoagulation)
During laser therapy, a laser is used to destroy blood vessels that supply oxygen and nutrients to the tumor. Without a source for fuel, cancer cells may die.
Cold treatments (cryotherapy)
Cryotherapy uses extreme cold to kill cancer cells. During cryotherapy, a very cold substance, such as liquid nitrogen, is placed in or near the cancer cells. Once the cells freeze, the cold substance is removed and the cells thaw. This process of freezing and thawing, repeated a few times per cryotherapy session, causes the cancerous cells to die.
Heat treatments (hyperthermia)
Thermotherapy uses extreme heat to kill cancer cells. During thermotherapy, heat is directed at the cancer cells using ultrasound, microwaves or lasers.
Surgery
Surgery for retinoblastoma includes:
Side effects of surgery include infection and bleeding. Removing an eye will affect your child's vision, though most children will adapt to the loss of an eye over time.
Clinical trials
Clinical trials are studies to test new treatments and new ways of using existing treatments. While clinical trials give your child a chance to try the latest in retinoblastoma treatments, they can't guarantee a cure. Ask your child's doctor whether your child is eligible to participate in clinical trials. Your child's doctor can discuss the benefits and risks of enrolling in a clinical trial.
When your child is diagnosed with cancer, it's common to feel a range of emotions — from shock and disbelief to guilt and anger. In the midst of this emotional roller coaster, you're expected to make decisions about your child's treatment. And while you're trying to sort it all out, friends and family may be calling for updates and to find out if they can help. It's overwhelming, to say the least. Everyone finds his or her own way of coping with stressful situations, but if you're feeling lost, you might try to:
In most cases, doctors aren't sure what causes retinoblastoma, so there's no proven way to prevent the disease.
Prevention for families with inherited retinoblastoma
In families with the inherited form of retinoblastoma, preventing retinoblastoma may not be possible. However, genetic testing enables families to know which children have an increased risk of retinoblastoma, so eye exams can begin at an early age. That way, retinoblastoma may be diagnosed very early — when the tumor is small and a chance for a cure and preservation of vision is still possible.
If your doctor determines that your child's retinoblastoma was caused by an inherited genetic mutation, your family may be referred to a genetic counselor.
Genetic testing can be used to determine whether:
The genetic counselor can discuss the risks and benefits of genetic testing and help you decide whether you, your partner or your other children will be tested for the genetic mutation.