A rare case of a non-neural granular cell tumor presenting as an enlarging right chest wall nodule in a 4-year-old male and review of the literature

Non-neural granular cell tumor was first described in 1991 as an unusual primitive, polypoid variant of the conventional granular cell tumor. To date, this neoplasm remains a rare entity and the cell of origin is uncertain. While the histological features are similar to the conventional granular cell tumor, it represents a distinct entity that is negative for S100 and lacks true nerve sheath differentiation. Here, we describe a case of a 4-year-old male who presented with a painless, soft nodule on his right chest wall that was slowly increasing in size. The mass was excised and sent for pathologic analysis. Microscopic examination reveals spindle and epithelioid cells with vesicular nuclei and prominent granular eosinophilic cytoplasm. Immunohistochemical analysis shows negative staining for S100 and AE1/AE3/PCK26 but is positive for CD68. A diagnosis of a non-neural granular cell tumor was made. We report a rare and diagnostically challenging case in a pediatric patient.