A Case of Skin Metastasis from Papillary Thyroid Carcinoma

Skin metastasis from papillary thyroid carcinoma is extremely rare. Due to similar histopathologic features, it is difficult to differentiate skin metastatic papillary thyroid carcinoma and some primary skin neoplasms without a clinical history. However, most of metastatic skin lesions showed a strong reactivity to the antithyroglobulin antibodies unlike primary skin neoplasms. Metastatic skin lesions must be completely removed and radiotherapy can be added. Investigators reported that prognosis of skin metastases from thyroid carcinoma is dismal and the average survival after it's diagnosis was only 19 months because distant metastases were often discovered at diagnosis of skin metastasis or during follow-up period. We report a case of skin metastasis from tall cell variant of papillary thyroid carcinoma. In our case, the anti thyroglobulin antibodies measured from cystic fluid from a skin lesion was more than 2000 IU/ml. Skin metastasis was diagnosed at 20 months after primary surgery for thyroid cancer and brain metastasis at 12 months after diagnosis of skin metastasis. Although skin metastasis is an ominous prognostic indicator in patients with thyroid carcinoma, a radical treatment for skin lesions and early diagnosis of distant metastasis could provide a chance to the patients to improve their survival.ope