Thyroid nodules TI-RADS grade. Grade 0: No abnormal ultrasound findings in clinically suspected cases, additional testing is required. Grade 1: Negative, with normal size and echogenicity of the gland and no nodules, cysts or calcifications on ultrasound. Grade 2: benign with 0% risk of malignancy, all requiring clinical follow-up. Grade 3: Probably benign with a risk of malignancy of <2%, puncture biopsy may be required. Grade 4: The probable percentage of malignancy is 5 to 50% needs to be combined with clinical diagnosis! Grade 5: Suggests the highest likelihood of cancer <95% Grade 6: Cytologically detectable cancer. Definite diagnosis of cancer!