Abstract
Granular cell tumours are rare, typically benign neuroectodermal neoplasms. While most follow an indolent clinical course, a small subset exhibits aggressive behaviour. We report a case of a granular cell tumour of uncertain malignant potential, non-neural type, in an 87-year-old male, presenting as a rapidly growing, ulcerated forehead nodule. Histopathology revealed high-risk features, including nuclear pleomorphism, increased mitotic activity, and perineural invasion. This case highlights diagnostic challenges in histomorphology, immunohistochemistry and application of conflicting diagnostic criteria—namely the Fanburg-Smith and Nasser frameworks—to determine malignancy in the absence of documented metastasis.
Keywords: Granular cell tumour; cutaneous non-melanoma skin cancer; malignant granular cell tumour; non-neural granular cell tumour
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