Nerve sheath myxoma of the tongue: report of a case and review of the literature

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Nerve sheath myxoma is a rare benign tumor of nerve sheath origin that typically presents as a small solitary skin nodule and rarely affects the oral cavity. A case of nerve sheath myxoma of the tongue in a 51-year-old male is reported. The patient had a painless submucosal nodule in the lateral margin of the tongue for several months. The tumor was surgically removed under local anesthesia. Histopathologically, the removed tumor consisted of several loosely textured myxofibrous nodules in which spindle- or stellate-shaped cells with eosinophilic cytoplasm and hyperchromatic nuclei were scattered. Immunohistochemically, the myxoid stroma was strongly positive for perlecan, a basement membrane type heparan sulfate proteoglycan, and the tumor cells were individually circumscribed by type IV collagen-positive fibers. In addition, the tumor cells were strongly positive for vimentin, S-100 protein, neuronspecific enolase, and cathepsin D. However, they were not positive for epithelial membrane antigen, neurofilament protein, CD34, CD10, calponin, actin, or any subtypes of keratin. A review of the literature revealed that 11 cases of oral nerve sheath myxoma had been documented. The mean age of the patients was 29 years old, and there was no predilection between males and females. They arose most frequently in the tongue.