Retinoblastoma Treatment (PDQ®): Treatment - Health Professional Information [NCI] - General Information
Fortunately, cancer in children and adolescents is rare, although the overall incidence of childhood cancer has been slowly increasing since 1975. Children and adolescents with cancer should be referred to medical centers that have a multidisciplinary team of cancer specialists with experience treating the cancers that occur during childhood and adolescence. This multidisciplinary team approach incorporates the skills of the primary care physician, an ophthalmologist with extensive experience in the treatment of children with retinoblastoma, pediatric surgical subspecialists, radiation oncologists, pediatric medical oncologists/hematologists, rehabilitation specialists, pediatric nurse specialists, social workers, and others to ensure that children receive treatment, supportive care, and rehabilitation that will achieve optimal survival and quality of life. (Refer to the PDQ Supportive and Palliative Care summaries for specific information about supportive care for children and adolescents with cancer.)
Guidelines for pediatric cancer centers and their role in the treatment of pediatric patients with cancer have been outlined by the American Academy of Pediatrics. At these pediatric cancer centers, clinical trials are available for most types of cancer that occur in children and adolescents, and the opportunity to participate in these trials is offered to most patients/families. Clinical trials for children and adolescents with cancer are generally designed to compare potentially better therapy with therapy that is currently accepted as standard. Most of the progress made in identifying curative therapies for childhood cancers has been achieved through clinical trials. Information about ongoing clinical trials is available from the NCI Web site.
Purpose of This Summary
This PDQ cancer information summary for health professionals provides comprehensive, peer-reviewed, evidence-based information about the formal ranking system used by the PDQ Editorial Boards to assess evidence supporting the use of specific interventions or approaches. It is intended as a resource to inform and assist clinicians who care for cancer patients. It does not provide formal guidelines or recommendations for making health care decisions.
Dramatic improvements in survival have been achieved for children and adolescents with cancer. Between 1975 and 2002, childhood cancer mortality has decreased by more than 50%. Childhood and adolescent cancer survivors require close follow-up because cancer therapy side effects may persist or develop months or years after treatment. (Refer to the PDQ Late Effects of Treatment for Childhood Cancer summary for specific information about the incidence, type, and monitoring of late effects in childhood and adolescent cancer survivors.)
Retinoblastoma is a relatively uncommon tumor of childhood that arises in the retina and accounts for about 3% of the cancers occurring in children younger than 15 years. The estimated annual incidence in the United States is approximately 4 per 1 million children younger than 15 years. Although retinoblastoma may occur at any age, it most often occurs in younger children; the annual incidence is 10 to 14 per 1 million in children aged 0 to 4 years. Ninety-five percent of cases are diagnosed before age 5 years, and two-thirds of these cases occur before age 2 years. Older age is usually associated with more advanced disease and a poorer prognosis.
Hereditary and Nonhereditary Forms of Retinoblastoma
Retinoblastoma is a tumor that occurs in heritable (25% to 30%) and nonheritable (70% to 75%) forms. Hereditary disease is defined by the presence of a positive family history, multifocal retinoblastoma, or an identified germline mutation of the RB1 gene. This germline mutation may have been inherited from an affected progenitor (25%) or may have occurred in utero at the time of conception, in patients with sporadic disease (75%). Hereditary retinoblastoma may manifest as unilateral or bilateral disease. The penetrance of the mutation (laterality, age at diagnosis, and number of tumors) is probably dependent on concurrent genetic modifiers such as MDM2 and MDM4.[4,5] Approximately 85% of patients with unilateral retinoblastoma do not have the hereditary form of the disease, whereas all children with bilateral disease are presumed to have the hereditary form, even though only 20% have an affected parent. In hereditary retinoblastoma, tumors tend to occur at a younger age than in the nonhereditary form of the disease. Unilateral retinoblastoma in children younger than 1 year should raise concern for the hereditary disease, whereas older children with a unilateral tumor are more likely to have the nonhereditary form of the disease.[6,7]