Approximately 18,100 new cases of thyroid carcinoma were diagnosed in the United States in 1999, ranking it 22nd in incidence among the major malignancies.1 Its frequency varies with gender and age and is highest among women between the ages of 30 and 70 years. The lifetime risk of being diagnosed with thyroid cancer is ˜0.64% for women and 0.25% for men.2 In 1998, ˜1200 of the 135,000 persons with thyroid carcinoma in the United States died of their disease.1 Between 1973 and 1992, its incidence among all ages rose steadily (almost 28%), whereas its mortality rates dropped more than 23%.2 The declining mortality rates are largely due to early diagnosis and effective therapy applied at an early tumor stage when it is most amenable to surgery and ¹³¹I therapy.3