Thyroid TI-RADS category 2 refers to thyroid nodules category 2, which are benign lesions that generally do not require treatment and can be reviewed periodically. TI-RADS is an acronym for Thyroid Imaging Reporting and Systematic Grading, which categorizes thyroid nodules into categories 1-6 based on the size, margins, and echogenicity of the nodule. Category 1 is no nodule, with a malignancy rate of 0%; Category 2 is benign nodule, with a malignancy rate of 0%; Category 3 is possibly benign nodule, with a malignancy rate of <2%; Category 4 is divided into 4a, 4b, and 4c, with a malignancy rate of 2% to 90%; Category 5 is highly suggestive of malignancy, with a malignancy rate of >90%; and Category 6 is biopsy-proven malignant nodule. Patients with thyroid nodules need to be treated under the guidance of a doctor and reviewed regularly.