Cutaneous Granular Cell Tumor in a Middle-aged Woman: Clinicopathological Insights from a Rare Schwannian Neoplasm

We report the case of a 51-year-old female with an unusual presentation of a cutaneous granular cell tumor (GCT) on the lower back. The lesion was asymptomatic, well-defined, and firm, with an initial clinical differential of dermatofibroma, pilomatricoma, or leiomyoma. Histopathological examination revealed a dermal tumor composed of large polygonal cells with granular eosinophilic cytoplasm and uniform nuclei, without atypia or necrosis. Immunohistochemistry confirmed the diagnosis with strong S100 and CD68 positivity. Due to tumor extension tumor extension to the deep resection margin, close follow-up was advised. Accurate diagnosis of cutaneous GCTs relies on histopathology and immunohistochemistry, as clinical and dermoscopic findings are often nonspecific. Complete surgical excision is the primary treatment, with a generally favorable prognosis. Awareness of malignant potential and proper surgical management is crucial for optimal outcomes.