Granular Cell Tumors

Epidemiology

Granular cell tumors (GCTs) are rare benign neoplasms that can occur anywhere in the body. About 50% of all GCTs occur in the tongue and 30% involve the skin. The remaining areas include the breast, muscle, tracheobronchial tree, larynx, and temporal bone. Multiple lesions have been reported in 5 to 10% of involved patients. GCTs typically present in the fourth decade of life and are more common in women (2:1) and in African Americans than Caucasians (5:1).

In the past, the histogenesis of GCTs was controversial and has led to the use of various terms to describe the same tumor (Abrikosov’s tumor, congenital epulis, nonchromaffin paraganglioma, granular cell myoblastoma, granular cell neurofibroma, myoblastic myoma, uniform myoblastoma, embryonal rhabdomyoblastoma). It is now believed that GCTs are felt to be of primitive neuroectodermal origin and the term granular cell tumor is the appropriate descriptor.

Clinical Findings

The presenting findings are nonspecific and vary with the primary location of the tumor. Patients with GCT involving the tongue often present with a visible or palpable mass, local pain, or dysphagia. Patients with GCT of the larynx complain of progressive hoarseness, shortness of breath, and dyspnea on exertion.