Recognize & Refer: Focus on retinoblastoma

Lisa Diller, MD

This month’s spotlight is Pediatric Oncology as Contemporary Pediatrics sits down exclusively with pediatric oncologist Lisa Diller, MD, vice chair, Clinical Affairs, and medical director, Clinical Cancer and Blood Disorders Service Line, Dana-Farber Cancer Institute, Boston, Massachusetts, to discuss the one key condition for which she believes community pediatricians should be especially aware-retinoblastoma.

Q.­ Dr. Diller, can you tell us why you think that retinoblastoma is something of particular concern for pediatricians?

A. ­Retinoblastoma is important for pediatricians because early detection can make a huge difference in terms of the outcome for the child. Knowing who might be at risk for retinoblastoma or what signs and symptoms are important to pick up for retinoblastoma is very important because the pediatrician is usually the first person to see the patient who might have retinoblastoma.

Q.­ What are the underlying reasons for maybe the increased severity of retinoblastoma in children?

A.­ It’s not really increased severity that I’m thinking about. I’m thinking about the possibility of picking up a retinoblastoma early that makes a huge difference. So, the severity of retinoblastoma in terms of the aggressiveness of the treatment is often related to delays in diagnosis, and if we can find retinoblastomas early and get the children into treatment, we can often avoid therapies that can have long-term effects for the rest of a child’s life, such as radiation therapy or losing an eye. That’s what I think it’s important for pediatricians to know.

Q. ­What advice can you offer as far as those diagnostic clues that the pediatrician should be on the lookout for to properly identify retinoblastoma?

A.­ First of all, retinoblastoma can run in families, so it’s very important to have a good family history. Often adult parents who had retinoblastoma may not be aware of the word retinoblastoma because they were treated at a very young age. They may have had an eye removed as a young child for reasons that they don’t know. They’ve had a glass eye their whole lives or a false eye their whole lives and they may not know this. So, unless the pediatrician is aware of the parent’s history he or she might be missing a clue. I had a recent patient, for example, whose mother lost an eye as a baby, was never told why, and then her child was diagnosed with retinoblastoma but she was completely unaware of the relationship between her likely retinoblastoma and what happened to her child.

Another sign or symptom that a pediatrician should be aware of-and that we’re seeing at increased frequency because people take so many photographs-is the lack of red reflex that you normally see in a photograph. In a photograph, when you shine a light, use the flash, you often see the reflection of the retina in both eyes. If a parent comes in with photographs where one eye is white and one eye is red, and it’s in more than one photograph, it’s something to be aware of. Because people take so many photographs these days using their cell phones, we can therefore know that we need to pay attention to that a little bit more than we used to when we were looking back at old photographs.

Another sign is redness of the eye itself or glaucoma, changes in vision, lazy eye, which is an indication of a change in vision, and then just leukocoria on exam or the physician seeing the lack of the red reflex. Those are all signs that pediatricians should be looking for.

Q. What are the best treatment options for retinoblastoma in children?

A. Children diagnosed with retinoblastoma with very small tumors often can be treated with what we call local therapies, mostly commonly cryotherapy or laser therapy, without needing a removal of the eye, also known as enucleation, or needing chemotherapy or radiation therapy. That’s one of the reasons we are very vigilant about doing exams on children who have a family history, for example, before they develop clinical signs of the disease, to pick up tiny little bits of retinoblastoma early to save them from those therapies.

The other treatments that are increasingly being used are chemotherapy delivered directly to the eye often through the ophthalmic artery where the child undergoes a cannulation of the ophthalmic artery and then chemotherapy is directed, is infused, directly to the retina. This allows us to avoid systemic chemotherapy, can be preserving of vision, can help us avoid removal of the eye, and avoids needing to use external beam radiation therapy.

Another therapy used when external beam radiation therapy is necessary is proton beam radiation, which is increasingly available and used in retinoblastoma patients because it can limit the dose in these very young children, limit the spread of the dosing of radiation outside of the eye. It really can target where the tumor is and avoid dosing areas such as the bones around the eye, because when we do that in very young children, the dose, to the bones around the eye or the soft tissues around the eye, is known to be associated with the development many years later of tumors of that area because of the tumorigenic effect of the radiation. So, if we can limit where we deliver radiation, we can hopefully reduce the risk that those secondary tumors will develop.

Q. Most importantly, at what point should a community pediatrician refer a patient to a specialist?

A. Any child who has a family history suspicious for retinoblastoma-that would be an unknown history of visual losses in multiple family members, a parent who has a glass eye, a parent who says there was something wrong with his/her eye as a baby but didn’t know what it was-those children all should be referred just based on the family history, and that should be done very early in infancy. Pediatricians are very good at looking for red reflex and, obviously, if they see an abnormality on physical exam, that should be referred. If a parent comes in with photographs that are of concern, I think that’s a reason to refer to a specialist as well, and that specialist would be a pediatric ophthalmologist. It’s not necessary to go directly to a pediatric oncologist at that point. I think the diagnosis is mostly made by observation by a pediatric ophthalmologist who has expertise in this field.

Q. Dr. Diller, is here anything else that you would like to add as a final thought for our community of pediatricians?

A. The other thing to remember is that increasingly genetic counselors who have expertise in cancer predisposition syndrome are able to take a family history and assess whether or not a child should be genetically tested for a risk of retinoblastoma. That is something that a pediatrician might consider if there’s a family history that is somehow concerning, and that might be the first level of referral before a pediatric ophthalmologist in certain situations.