Your child's healthcare provider will ask about your child's health history and symptoms. He or she will examine your child and pay close attention to the eyes. The healthcare provider will likely advise that your child see an eye specialist (ophthalmologist).
The ophthalmologist will check your child's eyes with special tools. Your child may need a dilated indirect ophthalmoscopic exam. Your child may be given anesthesia medicine to sleep through the exam.
Your child may need other tests such as:
- Ocular ultrasound. This test uses sound waves to create images of the eyes.
- CT scan. A series of X-rays and a computer are used to make images.
- MRI. Large magnets, radio waves, and a computer are used to make detailed images.
- Blood tests. Your child’s blood may be tested for signs of disease, and for gene changes.
A child may be diagnosed with no symptoms. This may be the case if you have a family history of retinoblastoma. Your child may have eye exams often to check for signs of the cancer.
After a diagnosis of retinoblastoma, these tests will help your child's doctor know if the cancer is inside the eye, how much of the eye is involved, and if it has spread beyond the eye. This process is called staging. The stage of a cancer is one of the most important things to know when deciding how to treat it. Doctors use 2 standard staging systems for retinoblastoma.
The newer system is called the International Classification for Intraocular Retinoblastoma. It divides these tumors into 5 groups lettered A through E. The groups are based on how likely it is that the eye can be saved. Group A means the tumor is small and not near important structures that allow your child to see. These tumors can likely be removed and vision can be saved. The higher the group, the more advanced the tumor is. A tumor in Group E means that doctors have little to no chance of saving the eye. The other groups then fall between these extremes.
The Reese-Ellsworth system is older and less commonly used. It groups retinoblastomas much like the International Classification system, based on whether the eye and vision can be saved. The system uses groups numbered 1 through 5. Group 1 means a good chance of saving the eye, and Group 5 means it's not likely. The other groups fall between this.
Doctors may use other staging systems. The staging process for retinoblastoma can be very complex. Be sure to ask your child's healthcare provider to explain the stage of your child's cancer to you in a way you can understand.