Solitary lung metastasis diagnosed 30 years after surgery for thyroid cancer.

A 75-year-old woman with a history of extrapulmonary malignancies (ie, thyroid cancer and colon cancer) underwent a lobectomy for a solitary nodule in the left lung. Pathologic examination showed a lung metastasis from papillary thyroid cancer treated 30 years earlier. Solitary metastasis to the lung from thyroid cancer is unusual, and our case presented the long interval from initial treatment to the identification of metastasis. A careful follow-up is mandatory, and one should keep in mind the delayed metastasis in the patient with differentiated thyroid cancer.