Fine-needle aspiration cytology of cutaneous granular cell tumor: Report of two cases with special emphasis on cytological differential diagnosis

Granular cell tumors (GCTs) are uncommon neoplasms with recently postulated origin from Schwann cell or neural crest. It can appear in different parts of the body and is most commonly found in the tongue. The cutaneous presentation is not that uncommon. Fine needle aspiration cytology (FNAC) has been suggested to be the diagnostic modality of choice. It will help to differentiate benign tumors from malignant ones and to differentiate GCT from frequent misdiagnoses such as granular histiocytic reaction, xanthogranuloma, rhabdomyoma, oncocyte rich lesions, alveolar soft part sarcoma (ASPS), epithelioid sarcoma, and carcinoma. We report two cases of GCT who presented with subcutaneous swellings in the right thigh and the left lumbar region for 24 months and 18 months, respectively. In the first case, a cytodiagnosis of chronic inflammation showing histiocytes was suggested while GCT was found in the second case. Subsequent histologic examination of the first case and immunocytochemistry in the second case gave the confirmatory diagnosis of GCT.