A Case of Granuloma Pyogenicum-like Cutaneous Metastasis to the Fingertip in Papillary Thyroid Carcinoma

ABSTRACT

Cutaneous metastasis of the papillary thyroid carcinoma(PTC) is very rare. We report a case of PTC that metastasized to the left fourth fingertip. Its cutaneous appearance was similar to granuloma pyogenicum. A 65-year-old woman who has PTC with regional lymph nodes involvement and pulmonary metastasis complained of a protruding hemorrhagic subungual mass on the left fourth finger for two months. The histopathologic findings showed papillary projections of the tumor cells surrounding the axial fibrovascular stroma and mitotic cells. The tumor cells showed a positive reaction with antithyroglobulin antibody in immunoperoxidase stain. To the best of our knowledge, this is the first case report of PTC that metastasized to the fingertip, and that showed granuloma pyogenicum-like cutaneous lesion at the metastatic site.