"Retinoblastoma is usually thought of as one disease. But there is good evidence that unilateral and bilateral retinoblastoma are distinct and progress in different ways," says Dr. Orjuela.
"There is also significant variation in how tumors respond to treatment, no matter how soon we initiate therapy," says first author Marco A. Ramrez-Ortiz, MD, chief of the department of Ophthalmology at the Hospital Infantil de Mxico Federico Gomez, Mexico City.
Education and Housing Conditions Predict Outcomes
Intriguingly, the researchers found that stage and survival in both forms of retinoblastoma were predicted by the mother's education level. Mothers with less formal schooling had children with significantly higher stage disease and significantly worse survival. Education was more important than the time needed for families to travel to the hospital or how many other young children needing childcare were in the household.
The child's home environment may be another contributing factor. Children born in homes with dirt floors had more advanced disease than their peers with different housing conditions, even after taking family income into account, says Dr. Orjuela. "There is a possibility that these children were exposed to metal or some other toxin in the dirt, although confirming this hypothesis would be difficult, given the rarity of the disease."
The finding on maternal education may offer a more fruitful intervention. "We may need to rethink the costs and benefits of screening programs and consider how to improve survival among children with less-educated parents," says Dr. Orjuela.
"Although pathologic stage and tu
|Contact: Timothy S. Paul|
Columbia University's Mailman School of Public Health