Ectopic thyroid as multiple nodules in bilateral lung lobes: a case report.

Ectopic thyroid rarely occurs in the thoracic or abdominal cavity, especially in the lung. Here, we describe an intrapulmonary thyroid tissue case in bilateral lung lobes without thyroid malignant history, which was found during a routine physical examination. A 37-year-old Chinese female showed multiple pulmonary nodules appearing in bilateral lung lobes on a computed tomography (CT) scan during a routine medical examination. To rule out the possibility of lung metastasis from occult cancer, a percutaneous lung biopsy was performed on a larger nodule. Histopathological examination confirmed that the nodule was completely consistent with normal thyroid tissue, which prevented the patient from requiring any unnecessary treatment. During the patient's follow-up, there was no abnormal thyroid function, and there was no change in the size of the nodule in the lung during serial CT scan. Currently, there is no guidance or consensus on the diagnosis of ectopic thyroid with bilateral multiple pulmonary nodules due to its rarity in clinical practice. When such pulmonary nodules are encountered, very careful diagnosis and follow-up should be performed.