Treatment for retinoblastoma, a cancer of the eye that occurs mainly in children, is often successful with surgical removal of the eye and radiation therapy. Although this treatment strategy is successful, it involves the loss of an eye as well as potential long-term side effects of radiation therapy. In a recent clinical study, researchers found that children with early-stage retinoblastoma may be able to keep the affected eye(s) and avoid radiation therapy by receiving chemotherapy and local treatments (treatments involving just the affected eye(s)).
Retinoblastoma, a disease most often occurring in children 5 years or younger, is characterized by the presence of cancer cells in the retina, a nerve tissue of the eye. Although this type of cancer may affect one or both eyes, it usually does not spread to other parts of the body unless it is very advanced. Treatment for retinoblastoma depends on the stage (extent) of disease and whether one or both eyes are affected. Treatment usually consists of surgical removal of the affected eye (called enucleation) and external-beam radiation therapy (high-energy rays, delivered by a machine outside the body). Other options that may be part of treatment or are under evaluation include cryotherapy (use of cold temperatures to kill cancer cells), photocoagulation (use of lasers to destroy blood vessels that go to the cancer cells), thermal therapy (use of heat to kill cancer cells), plaque radiation therapy (a method of applying radioactive material directly into or near the cancer cells), or chemotherapy (use of drugs to kill cancer cells).
Researchers have been exploring the use of chemotherapy combined with local treatments in order to sustain the high cure rates achieved with standard treatment but avoid the damaging long-term side effects of radiation. A medical group in Switzerland evaluated the effectiveness of chemotherapy and local treatment in over 30 children that had been newly diagnosed with retinoblastoma. Patients received 2 to 5 courses of combination chemotherapy consisting of etoposide and carboplatin. After each course of chemotherapy, additional local treatment was administered, consisting mostly of cryotherapy, photocoagulation, and plaque therapy.
All cancers showed a response to this treatment. Among the patients with less advanced disease, almost 70% achieved a complete disappearance of cancer with chemotherapy and local treatment alone. However, in patients with more advanced cancer, only 40% were able to avoid the aggressive treatment with external beam radiation and/or enucleation without a return of their cancer. The findings from this study indicate that chemotherapy combined with local treatment may be an effective treatment for patients with low-grade retinoblastoma, permitting the avoidance of the loss of an eye or radiation therapy. This is in contrast with the results for patients with more advanced cancer, an area where further studies are needed to develop more effective therapies.
Parents of children with retinoblastoma may wish to talk to their physicians about participating in ongoing clinical trials of new methods of avoiding radiation therapy and/or enucleation. Two sources of information on ongoing clinical trials that can be discussed with a doctor include a comprehensive, easy to use service provided by the National Cancer Institute (cancer.gov) and eCancerTrials.com. eCancerTrials.com also performs personalized clinical trial searches on behalf of patients. (Journal of Clinical Oncology, Vol 18, No 15, pp 2990-2995)