A Case of Symplastic Glomus Tumor

Glomus tumor is a benign lesion characterized by vessels and glomus cells in the varying proportion and it classically presents as a solitary, painful papule or nodule. Occasionally it displays unusual histopatholgic features diagnosed as “atypical” glomus tumor, including malignant glomus tumor, glomus tumor of uncertain malignant potential, glomangiomatosis, and symplastic glomus tumor. Glomangiomatosis and symplastic glomus tumor reveal benign biologic behavior. We report herein a typical case of symplastic glomus tumor showing marked nuclear atypia, its only unusual feature comparing with classical one, in addition to the typical clinical and pathological features.