Oral Granular Cell Tumors Workup

Updated: Mar 20, 2018
  • Author: Steven Brett Sloan, MD; Chief Editor: Dirk M Elston, MD  more...
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Laboratory Studies

No clinical laboratory tests are used for these lesions. A definitive diagnosis requires biopsy.



Conservative excisional biopsy is indicated because both lesions are rarely larger than 2 cm in diameter. As a general rule, the depth of biopsy for granular cell tumors approximates the diameter of the lesion. Margins do not need to be extensive; generally, a few millimeters is adequate.

The depth of biopsy for congenital epulis is the periosteum. Removal of bone is not indicated. Since these are exophytic lesions, surgical margins do not need to be much greater than the clinical margins.


Histologic Findings

The granular cell tumor is characterized by the presence of sheets or clusters of plump, polygonal cells with a granular cytoplasm. These lesions are not circumscribed and often come into intimate contact with the overlying surface squamous epithelium. A frequent finding is pseudoepitheliomatous hyperplasia of the overlying epithelial layer. These cells generally are uniform and do not exhibit significant atypical features. Malignant granular cell tumors, which fortunately are rare, may have a very benign histologic appearance. Tumor cells more or less stain uniformly positive for S-100 protein, neuron-specific enolase, CD68, PGP9.5, and inhibin alpha. [21, 22, 23, 24]

Congenital epulis also contains sheets and/or clusters of plump cells with a granular cytoplasm.

Pseudoepitheliomatous hyperplasia generally is not present. Congenital epulis lacks specificity for S-100 protein and is vimentin positive.