Aggressive treatment appears to significantly improve survival among patients who develop radiation-induced osteosarcoma following treatment of childhood cancer, according to a study published in the International Journal of Radiation Oncology, Biology, Physics.
Osteosarcoma is a type of cancer that originates in the bone. Standard treatment for osteosarcoma depends largely on the stage or extent of spread. If the cancer is confined to an extremity, standard treatment typically consists of chemotherapy, surgery to remove the cancer, and possibly radiation therapy.
Radiation-induced osteosarcoma results from radiation therapy for a prior cancer. In the past, radiation-induced osteosarcomas had a poor prognosis. In order to describe the characteristics of radiation-induced osteosarcoma that develops after treatment for childhood cancer, researchers reviewed published reports of this condition.
The researchers identified 30 relevant studies published between 1981 and 2004. The studies evaluated patients who were under the age of 21 at the time of their first cancer. The information collected from these studies included type of cancer treated with radiation therapy, radiation dose, time between radiation therapy and the development of radiation-induced osteosarcoma, and treatment and outcome of radiation-induced osteosarcoma.
The 30 evaluated studies included a total of 109 patients. Half the patients were under the age of six years at the time of their initial cancer. The most common primary cancers were Ewing’s sarcoma, rhabdomyosarcoma, retinoblastoma, Hodgkin’s lymphoma, brain tumor, and Wilm’s tumor.
- Radiation-induced osteosarcoma developed a median of eight years after radiation therapy.
- Three-year overall survival was 42%.
- Five-year overall survival was 40%.
- Survival after osteosarcoma did not vary by age at radiation therapy, primary cancer site, total radiation dose, or time between radiation and development of osteosarcoma.
- Survival did vary by type of treatment for radiation-induced osteosarcoma. Five-year overall survival was 17% for patients treated with chemotherapy alone, 50% for patients treated with surgery alone, and 68% for patients treated with surgery and chemotherapy.
The researchers conclude that “Patients who develop [radiation-induced osteosarcoma] should be aggressively treated, because outcome is not as dismal as once thought.”
Reference: Koshy M, Paulino AC, Mai WY et al. Radiation-Induced Osteosarcomas in the Pediatric Population. International Journal of Radiation Oncology, Biology, Physics . 2005;63:1169-1174.