The experimental drug selumetinib may allow some patients with advanced thyroid cancer to overcome resistance to radioiodine (RAI), the most effective therapy for the disease, according to new research from Memorial Sloan-Kettering Cancer Center. Published in the Feb. 14 issue of the New England Journal of Medicine, the study offers new hope for patients with a disease that can have a poor prognosis. An estimated 56,000 new cases of thyroid cancer are diagnosed each year in the United States, and that number is on the rise, according to the National Cancer Institute. About 5 percent of these patients will eventually develop distant metastatic disease, and the ten-year survival rate for patients with metastatic tumors that fail to respond to RAI is approximately 10 percent.