[2] Granular cell tumors are derived from neural tissue, as can be demonstrated by immunohistochemistry and ultrastructural evidence using electron microscopy.

[3] Multiple granular cell tumors may seen in the context of LEOPARD syndrome, due to a mutation in the PTPN11 gene.

Of the head and neck cases 70% of lesions are located intraorally (tongue, oral mucosa, hard palate).

[5] Granular cell tumors are also found in the internal organs, particularly in the upper aerodigestive tract.

The usual presentation is of a slow growing behavior, forming a polygonal accumulation of secondary lysosomes in the cytoplasm.