Retinoblastoma is a tumor that arises in the cells of the retina, the light-sensitive tissue at the back of the eyeball, following mutation of the gene RB1. It is the third most common form of cancer in infants. Left untreated, the cancer spreads and is fatal. Retinoblastoma strikes about 250-350 infants and young children each year in the United States.
The St. Jude study suggests a new approach to treatment that could save both lives and vision, according to Michael A. Dyer, PhD, an assistant member of the department of Developmental Neurobiology. The new treatment might also prevent recurrence of retinoblastoma in children whose cancer is very advanced, he noted. Dyer is the senior author of the Clinical Cancer Care report.
The study showed that combination therapy with topotecan and carboplatin is superior to the standard triple-drug therapy using vincristine, carboplatin and etoposide. The new combination eliminates the use of etoposide, which is known to increase the risk of the children getting a form of leukemia called acute myeloblastic leukemia. The findings also suggest that vincristine, which is used in the standard combination therapy, contributes little to the treatment of retinoblastoma, and therefore can be eliminated from therapy.
Dyer's group was prompted to look for new treatments because of the difficulty in managing this cancer. Patients with retinoblastoma usually undergo enucleation (removal of the diseased eye); and children with retinoblastoma in both eyes often must undergo anticancer therapy in order to avoid the loss of both eyes and blindness.