RESUMEN
Objectives To study the clinical characteristics,diagnosis,treatment and prognosis of cancer metastases to the thyroid gland.Methods At Tianjin Medical University Cancer Hospital,from 1980 to 2016 30 patients were identified with a metastatic malignant tumor of the thyroid gland.Results Primary tumor sites were in the esophagus (26.7％),lung (16.7％),and kidney (13.3％).The median age at discovery of thyroid metastasis was 56 years old.The time lapse ranged from 0 to 108 months.There were 18 patients with metachronous metastasis with median survival of 36 months,12 patients were with synchronous metastasis,and the median survival was 8 months (P ＜ 0.01).20 patients were treated with thyroid surgery,and of which 15 patients were given post-op radiotherapy and chemotherapy.Patients who underwent thyroid resection had a median survival of 15 months,while that was 8 months in those without thyoid surgery (P ＜ 0.01).Conclusions Metastases to the thyroid gland is a rare clinical phenomenon,the prognosis of patients is mainly related to the biological behavior of primary tumors,but surgical resection and combined treatment can increase the survival rate.