Granular cell tumor of hand presenting as subcutaneous nodule mimicking dermal adnexal tumor: A diagnosis by cytology

Abstract

Granular cell tumor (GCT) is an uncommon tumor and is believed to be of schwannian origin. GCT is benign but rare malignant cases are recorded. GCT occurs in almost any part of the body. The common sites are the tongue, skin, and subcutaneous tissue. GCT of hand is an extremely rare. Till date only 17 cases are reported in the literature. Preoperative diagnosis of GCT is important, because GCT mimics dermal adnexal tumor in subcutaneous tissue, other soft tissue tumor or inflammatory lesions. GCT is composed of large polygonal cells with eosinophilic granular cytoplasm and these cells are often immunoreactive for the S-100 protein. Fine-needle aspiration cytology has been suggested to be diagnostic modality of choice and this would undoubtedly aid the correct diagnosis. Excision with wide surgical margins is curative for benign GCT. Recurrence and malignant transformation requires regular follow-up. Here, this communication documents a case of cytological diagnosis of the granular cell tumor of hand in a 21-year-old female, clinically suspected to be a dermal adnexal tumor.

Granular cell tumor: An uncommon benign neoplasm

“…The characteristic cytologic findings are large, pale oval, round, bipolar or polygonal cells with abundant fine or coarsely granular, eosinophilic cytoplasm, inconspicuous cell border, eccentrically located nuclei, fine nuclear chromatin and indistinct nucleoli. [ 7 ] Histopathology shows the same cellular architecture, pseudoepitheliomatous hyperplasia and cords of cells infiltrating into the dermis. Electron microscopy indicates that the characteristic granularity is owing to the accumulation of lysosomes.…”

Recurrent benign cutaneous granular cell tumor: A case report

“…and mitosis (>2/10 high power fields at ×200 magnification). [ 4 5 7 8 ] In the present case, size of the tumor was 7 cm, still it was labeled as benign due to the absence of both necrosis and mitosis.…”

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

“…Rarely benign adnexal tumors may also come under the clinical differential diagnosis but the cytology of GCT is very characteristic and different from these. [ 11 ] Also, the adnexal neoplasms are cytokeratin positive.…”