Benign glandular schwannoma

Glandular schwannoma is a rare variant of schwannoma characterized by the p resence of glands in an otherwise typical schwannoma. We report a patient w ith benign glandular schwannoma occurring on the scalp, a site not previous ly reported. Histologically, a well-defined, encapsulated oval nodule was o bserved in the subcutaneous tissue. The nodule was composed of a spindle ce ll component and glandular structures. The spindle cell component stained p ositively for S-100 protein. All of the glandular epithelium stained with C AM 5.2 and epithelial membrane antigen but not with S-100 protein. The glan dular epithelium was focally positive for carcinoembryonic antigen. The his togenesis of the glandular elements in these tumours is still debated. The variable size of the glandular structures in our case was evidence against an entrapped normal sweat gland origin. The glandular epithelium did not st ain with S-100 protein at all, but stained with CAM 5.2, which did not supp ort a direct metaplastic origin of the epithelial elements from the schwann ian component. A few scattered CAM 5.2-positive cells and microglandular st ructures in our case may be the initial differentiating epithelial elements possibly derived from pluripotential neural crest cells.