1.Single solid nodule more than 1 cm in size. 2.Single solid nodule less than 1 cm but with calcification or abnormal blood flow or lymph node enlargement. 3.Single cyst more than 2-3 cm in size. 4.Multiple nodules in which the largest nodule is more than 2 cm or nodules with calcification or abnormal blood flow or lymph node enlargement. 5, Thyroid nodule with previous history of neck radiation exposure or treatment. 6, Age less than 20 years old or greater than 70 years old. 7, Male patients with thyroid nodules. 8.Patients with retrosternal thyroid enlargement. 9.Patients with sudden increase in thyroid nodules recently. 10.Thyroid nodules with pressure, voice change, swallowing difficulty and irritating cough.