A small number of atypical follicular epithelial cells found by thyroid puncture is a follicular lesion of undetermined significance and should be repeated by puncture, molecular testing, or surgery. A small number of atypical follicular epithelial cells found by thyroid puncture indicates that the follicular cells and structure have changed and are different from normal follicular cells; however, the number of atypical cells is not sufficient to classify them as suspected follicular neoplasms or suspected malignancies, and therefore, they are classified as cellular atypical lesions of undetermined significance or follicular lesions. When the results of puncture biopsy cannot determine the definite nature of the nodule, fine-needle puncture biopsy can be performed again, and molecular markers such as BRAF (V600E) can be used to jointly determine the benign or malignant nature of the nodule, or the patient’s wishes and other choices such as direct surgery of the thyroid gland lobes. Patients are advised to consult a specialist for further examination and treatment.