Neck ultrasonography is the best tool for lookingat the sizeand shapeof the thyroid nodule. Size is important. Except in special cases, nodules smaller than 1 centimeter (less than about half an inch) shouldnot be biopsied.Many nodules do not need a biopsy. Some aremonitored with follow-up ultrasonography.If the nodule looks like it may contain a cancer, the next step isto perform a fine-needle aspiration biopsy. A thin needle is used toremove some of the cells out of the thyroid nodule. A pathologistwill test the sample and give results, usually labeling it as benign,indeterminate, suspicious for, or positive for a cancer.