Granular cell tumor, otherwise known as Abrikossoff's tumor, most often presents as stable or slow growing, benign, and solitary tumor less than 3
cm in diameter. Two-thirds of cases are reported in women, and two-thirds of cases are reported in black persons. It most commonly occurs between the fourth and sixth decades of life. The neoformation can affect all parts of the body with the highest concentration in areas with highest concentration of peripheral nerves. The head and neck areas are affected in 50% of cases and of these, 70% are located interorally (tongue, oral mucosa, and hard palate). The cutis and the subcutaneous tissue are affected in 30% of cases, the breasts in 15%, and the respiratory system in 10% of cases. Only 1% to 3% of all reported cases are malignant [1
The malignancy of the neoformation is suggested by the rate of growth, the size (>4
cm), and the presence of necrotic and hemorrhagic areas whereas histologically it shows a high mitotic index and cellular and nuclear pleomorphism [8
Both benign lesion such as hyperkeratotic or verrucous lesion and malign lesion such as squamous cell carcinoma or acral melanoma have to be considered as differential diagnosis.
Histologically, the benign tumor appears in no ulcerated nodular form, in varying dimensions from 2 to 5
cm. Microscopically the cells appear to show small, round, and central nuclei. The neoformation cells have a low mitotic index. The cytoplasm contains an abundant granular eosinophilic substance [1
]. Typically the granules stain positive with periodic acid-Schiff (PAS) staining and are resistant to diastase digestion; they also stain with Sudan black B.
The origin of the granular cell tumor is controversial. The most substantiated hypothesis at present is that the lesion is a consequence of altered cellular metabolism of the Schwann cells. This theory is supported by the presence of the protein S-100, a marker regularly expressed in tumors of neural origin [10
The treatment, exclusively surgical, consists of local excision of the neoformation. The case we report is uncommon: only three granular cell tumors have been reported on the toe; none of these were treated with conservative surgery and reconstructed with a dermal regeneration template. Amputation has been the surgical first choice.
In 15% of cases reappearance locally is possible in the incomplete excision of the neoformation [1
]. The use of radiotherapy and chemotherapy is advisable only in treating the malignant forms of such tumors.