Pleural metastasis of thyroid carcinoma diagnosed by thoracoscopy under local anesthesia

A 79-year-old male patient with no symptoms was referred to us with incidentally detected pleural effusion and nodules. He had previously been diagnosed with papillary thyroid carcinoma (PTC) and had undergone left subtotal thyroidectomy 12 years before his referral. Four years after the operation, he experienced a relapse limited to the cervical lymph node and was treated with neck dissection. He experienced no further recurrence until his referral. Thoracoscopy was performed under local anesthesia to confirm the diagnosis because thoracentesis was precluded by the small quantity of pleural effusion and the nodules. Many vivid red pleural masses were evident as was a small amount of bloody pleural effusion. The patient was diagnosed with pleural metastasis of PTC, which has a poor prognosis. Because of this poor prognosis, prompt diagnosis is essential. Thoracoscopy under local anesthesia can allow the prompt diagnosis of cases in which safe thoracentesis would be difficult.