Granular cell tumours (GCTs) are infrequent submucosal growths, presumed to arise from Schwann cells, distinguished by large polygonal cells containing numerous lysosomes. This study sought to explore whether GCTs display features of antigen-presenting cells (APCs) or neural crest cells (NCCs) using immunohistochemistry and to contrast their expression patterns with Schwannomas. Expression of APC-associated markers (CD68, HLA-DR, CD163, CD40, CD11c) and NCC-associated markers (S100, SOX10, NSE, GAP43) was analyzed in 23 GCTs and 10 Schwannomas. Furthermore, RT-qPCR was conducted on 6 GCT cases to assess a possible NCC developmental signature. GAP43 emerged as a novel NCC marker for GCTs, while CD68 and HLA-DR staining provided limited support for an APC-like profile. RT-qPCR did not detect an NCC developmental program in GCTs, likely due to technical constraints.
