Alveolar soft-part sarcoma of tongue.

Alveolar soft-part sarcoma is a clinically and morphologically distinct soft-tissue sarcoma of adolescent and young adult patients. Though immunohistochemical stains implicate a myogenic origin, the histogenesis of this tumor has not yet been established. Its high vascular nature leads to dissemination of the tumor cells into the bloodstream and metastasis. It comprises less than 1% of all soft-tissue sarcomas and less than 0.1% of sarcomas of the head and neck, preferably involving the orbit (48%) and tongue (25%). Lingual involvement is very rare and only about 31 cases have been reported in English literature. Their deceivingly indolent clinical courses often lead to misdiagnosis and delayed treatment. The reported case indicates its asymptomatic nature and microscopic similarity to granular cell tumor, which is the common benign tumor of the tongue.