A patient of mine was recently diagnosed with retinoblastoma. Can you tell me about the disease — and is it hereditary? Thanks.
Registered Nurse – Carlsbad, New Mexico
Dr. Greene`s Answer:
When you see the red-eye effect in a photograph, you are looking at a clue to the presence or absence of retinoblastoma, an important childhood cancer.
Retinoblastoma, which is usually found in infants and toddlers, is cancer of the eye. It first arises in the retina (the innermost layer of the eyeball, where light is sensed and transformed into a nerve signal to be passed on to the brain), but can move to other parts of the body. This tumor blocks the view from the outside of the eye to the retina, preventing the “red-eye effect” in photographs. During my residency, I took care of a chid with retinoblastoma who was diagnosed because the family noticed she had a “red-eye effect” in only one of her eyes.
Unfortunately, about a third of children with retinoblastoma have cancer in both eyes. In this form, retinoblastoma is a hereditary condition that is passed through families in a dominant fashion (if a person with bilateral retinoblastoma has children, about 50 percent of his or her offspring will have retinoblastoma.) The retinoblastoma gene is on the long arm of chromosome 13.
Retinoblastoma also exists as a non-hereditary condition. Retinoblastoma in only one eye is usually not hereditary. (Still, of those who have retinoblastoma in one eye, as many as 20 percent have inherited this disease.)
The standard treatment for retinoblastoma is taking out the eye. The process of removing the eye from the socket is called enucleation. The surgeon will also try to remove tissue from the lining of the socket, and as much of the optic nerve as possible. The optic nerve can be a highway for tumor spread to the brain. Other treatment modalities may be considered when the tumors are small.
If both eyes are involved, sometimes one eye is left in and other treatments are used in an attempt to preserve some vision in the remaining eye. Treatments on the remaining eye may include radiation or cryotherapy (using extreme cold to kill the tumor — like freezing a wart). Both of these alternatives can be quite painful, requiring daily general anesthesia for weeks.
The overall survival rate for retinoblastoma is very good — over 90 percent. This rate is even higher for those in whom the tumor is limited to the eyes. If the tumor has already spread beyond the eyes at the time of diagnosis, however, cure is unlikely.
Surviving retinoblastoma often means life without one or both eyes. It also means an increased risk of other cancers. About 30 percent of those with hereditary retinoblastoma will develop another type of cancer within 30 years. The non-hereditary forms of retinoblastoma do not carry such a dramatically increased risk.
Currently researchers are investigating the long-term quality of life in survivors of retinoblastoma. There is also a great deal of effort made both to standardize internationally the treatment of this condition and to improve the chances of avoiding vision loss.
The first sign of this devastating disease is white light reflected from one or both pupils instead of red. This may be seen by a family member in a snapshot or by a physician during a physical exam. When you see red in the pupil, you are seeing the retina; when you see white, you might be seeing a tumor. Every baby and toddler should have a physician look in the eyes with an ophthalmoscope to check for this red reflex. If a white reflection is seen, there are more than 2 dozen possible causes, but the child should certainly be evaluated for retinoblastoma.
I’m so sorry your patient has been diagnosed with retinoblastoma. I have treated children with this cruel disease, and I have always been amazed by their courage and joy. The entire family will need your support and compassion to face the difficult struggle ahead of them, but I’m sure that your work with them will enrich your life far more than you could possibly imagine.