A TI-RADS 5 thyroid nodule with repeat Bethesda III cytology and final diagnosis of classic papillary thyroid carcinoma: A case report

Background: Bethesda category III thyroid nodules remain a diagnostic challenge because the risk of malignancy is intermediate and management should not rely on cytology alone. Ultrasound risk stratification is particularly important when cytological findings are discordant or persistently indeterminate.
Case presentation: We report the case of a 50-year-old woman presenting with swallowing discomfort. Thyroid ultrasound demonstrated a highly suspicious right thyroid nodule classified as ACR TI-RADS 5, together with a suspicious right level IV cervical lymph node. Initial fine-needle aspiration (FNA) of the thyroid nodule showed nodular hyperplasia, whereas repeat FNA after follow-up yielded Bethesda III cytology. Because of the persistently high-risk ultrasound appearance, the patient underwent total thyroidectomy with central neck dissection. Histopathology confirmed classic papillary thyroid carcinoma, while the dissected lymph nodes were inflammatory.
Conclusion: This case highlights the importance of integrating ultrasound findings, repeat cytology, and clinical judgment in the management of Bethesda III thyroid nodules. A benign or indeterminate FNA result does not exclude malignancy when sonographic features are strongly suspicious.