What is retinoblastoma?
Retinoblastoma is a type of pediatric cancer that develops on the retina in the eye. Your retina works with your brain to help you see. The retina is located in the back of your eye. It has layers of cells that sense light and send information to your brain.
Retinoblastoma almost always develops in children under age 5. Retinoblastoma treatments include cryotherapy, chemotherapy, radiation and surgery. The outlook depends on several factors, including the tumor’s size and location and whether the cancer has spread. If the tumor hasn’t spread beyond the eye, most children with retinoblastoma live cancer-free after treatment.
How common is retinoblastoma?
Retinoblastoma is very rare. About 200 to 300 children are diagnosed with retinoblastoma every year. It affects boys and girls equally.
Most often, the condition affects one eye. In about a quarter of cases, both eyes are affected.
What are the stages of retinoblastoma?
Healthcare providers classify retinoblastoma using a process called staging. They consider the tumor’s location and whether it has metastasized (spread) to other parts of the body, such as the brain, bones or organs. Most retinoblastoma tumors are detected before they spread to the rest of the body.
Your child’s team of providers uses staging information to select the most appropriate treatment plan. Retinoblastoma stages include:
- Stage 0: The tumor is only in the eye. Healthcare providers can treat the cancer without surgery.
- Stage I: The tumor is only in the eye. Providers can treat the cancer by removing the eye. No cancer cells remain after treatment.
- Stage II: The tumor is only in the eye. Cancer cells remain after the eye has been removed, but the cells are so small they only appear under a microscope.
- Stage III: The cancer spreads to tissues surrounding the eye socket (stage IIIa). Or it spreads to lymph nodes in the neck or ear (stage IIIb). Lymph nodes are glands that help the body fight infection.
- Stage IV: The cancer spreads to other parts of the body. Cancer that spreads may affect the bones or liver (stage IVa) or the brain or spinal cord (stage IVb).
Symptoms and Causes
What causes retinoblastoma?
A genetic mutation (a change in the child’s genes) causes retinoblastoma. The gene that causes retinoblastoma is called RB1. The mutation causes cells in the eye to grow uncontrollably, forming a tumor. Around 40% of the time, the child inherits the RB1 mutation from a parent (heritable retinoblastoma). In about 60% of cases, the gene change occurs spontaneously. In those cases, healthcare providers aren’t sure what caused the genetic mutation (nonheritable retinoblastoma).
About 60% of children with heritable retinoblastoma will develop tumors in both eyes (bilateral) and 30% develop a tumor only in one eye. The remaining 10% of children may not develop retinal tumors, but are carriers of the gene. In children who develop tumors in both eyes, the tumors may form at the same time or they can grow months or years apart. Children who have nonheritable retinoblastoma develop tumors in only one eye (unilateral).
What are the symptoms of retinoblastoma?
Most often, the first sign of retinoblastoma is a change in the way the eye looks. Symptoms can affect one eye or both eyes. Retinoblastoma symptoms include:
- White pupil (leukocoria): Leukocoria is usually the first sign of retinoblastoma. The pupil (the round, black center of the colored part of the eye) appears white or cloudy. It may always be dilated. The pupil may look white at certain angles or in a photo that used a flash (pupils usually look red in a flash photo). Rarely, pupils are different sizes.
- Crossed eyes (strabismus): Eyes may appear misaligned, or one eye turns in a different direction than the other. Strabismus can range from mild to severe.
- Red or inflamed eyes: Inflammation and irritation can appear anywhere on the eye. The eyes may hurt or be sensitive.
Diagnosis and Tests
How is retinoblastoma diagnosed?
Healthcare providers usually diagnose retinoblastoma with a specialized eye examination. During the exam, your child will be under general anesthesia. Your child receives medicine through a vein and sleeps throughout the exam. The eye doctor uses instruments and lights to look at the retina.
Your child’s provider may also perform imaging studies or other tests to see if the cancer has spread to other parts of the body. These tests include:
- Imaging studies: MRI scans and ultrasounds produce detailed pictures of your child’s eyes.
- Spinal tap. A spinal tap detects cancer cells in the fluid that surrounds your child’s spine and brain.
- Bone marrow biopsy: To see if the cancer has spread to the bones and bone marrow, your provider may order a bone marrow biopsy. Bone marrow is spongy tissue at the center of large bones.
Management and Treatment
How is retinoblastoma treated?
Treatments vary based on the stage of the disease. Your child’s team of providers will consider whether cancer is only in the eye (intraocular retinoblastoma). Treatments may be different if it has spread to other parts of the body (extraocular retinoblastoma). Retinoblastoma treatments include:
- Chemotherapy: Healthcare providers inject chemotherapy drugs through artery or vein. The drugs stop cancer cells from multiplying. Your child may receive chemo treatments over several weeks or months.
- Cryotherapy (cryoablation): Cryotherapy treatment uses extreme cold (usually liquid nitrogen) to destroy cancer cells.
- Laser therapy: Laser procedures include photocoagulation and thermotherapy. Providers use lasers to destroy tumors with heat.
- Radiation: Radiation therapy kills cancer cells and stops them from multiplying. To treat retinoblastoma, your child’s provider may recommend a type of radiation called radioactive plaque therapy. Providers secure a plaque (a tiny device) onto the eyeball over the tumor. Over several days, the plaque delivers radiation directly to the tumor. Providers remove the plaque after treatment, and the tumor shrinks over time.
- Surgery: For large tumors, providers may need to remove the entire eyeball and part of the optic nerve behind the eyeball. This surgery is called enucleation. Your child’s provider can place an artificial eyeball and lens (similar to a contact lens) inside the eye socket.
Can retinoblastoma be prevented?
It’s not possible to prevent nonheritable retinoblastoma.
If you or your partner had retinoblastoma as a child, you have a 50% chance of passing the condition to your children. If you have a family history of retinoblastoma or have the RB1 gene change, you may want to consider genetic testing before having children. Children with a family history of retinoblastoma should get regular eye exams starting at birth. It’s important to detect and diagnose retinoblastoma early. Early diagnosis can significantly improve the prognosis. Catching cancer early may prevent loss of vision.
Outlook / Prognosis
What is the outlook for people with retinoblastoma?
With treatment, children who have retinoblastoma that has not spread to other parts of the body have a 96.5% survival rate at 5 years. Cancer specialists measure cancer outlook by the five-year survival rate. For kids with more advanced retinoblastoma, the outlook varies. The prognosis depends on whether the cancer has spread to the brain and spinal cord.
Children with heritable retinoblastoma have a higher risk of developing another type of cancer later in life. Later cancer is most often cancer of the bones (osteosarcoma). If cancer develops after retinoblastoma, it usually appears within 30 years after treatment.
What do I need to know about follow-up care after retinoblastoma treatment?
Follow-up care is essential after your child has finished treatment for retinoblastoma. Through regular checkups, your child’s provider can check if cancer has returned. They can also detect new tumors and monitor your child for side effects of treatment.
Children who had surgery to remove an eye will receive a prosthetic (fake) eye, which is almost like a big contact lens. A prosthetic eye looks natural. It isn’t painful to wear, but it may take some time for your child to get used to it. Your child’s provider will teach you and your child how to care for the prosthetic eye. You’ll have regular visits to make sure it fits properly.
When should I call my healthcare provider about retinoblastoma?
Call your provider if you notice any signs of retinoblastoma or changes in your child’s eyes or vision. Talk to your provider if you or your partner has a family history of retinoblastoma or you know you have the RB1 gene mutation. You may want to consider genetic counseling before having children.
What do I need to know if I have a family history of retinoblastoma?
If you have a family history of retinoblastoma, be sure to schedule regular eye exams for your child and other family members. The RB1 gene that causes retinoblastoma can also cause retinocytoma, a benign (noncancerous) eye tumor. Retinocytoma can develop in people of all ages.
A note from Cleveland Clinic
Receiving a cancer diagnosis is life-changing. But there is hope. Researchers and healthcare providers continue to develop promising treatments that improve the outlook for children with this type of cancer. If your child has retinoblastoma, you may want to consider participating in a clinical trial for new treatments. Talk to your provider about joining a cancer support group. Many parents and families find that support groups offer hope and encouragement.