In two cases of spiradenoma, studies of enzymatic reactions showed complete absence of glycogen phosphorylase and acid phosphatase enzymes. Irregular foci of succinic dehydrogenase, as well as nicotinamide adenine dinucleotide, reduced (NADH), were observed. The small tumoral nodules were surrounded by nerve fibers, which can be readily demonstrated by techniques using cholinesterase. Study of the ultrastructure of the tumor revealed that it was composed of two main types of cells, but neither secretory granules nor glandular structures could be observed. The results of our study of the spiradenoma, its basic similarity to other tumors of the basaloid type, and its chemical and ultrastructural features suggest that it is a tumor of basal cell differentiation.
Castro C, Winkelmann RK. SpiradenomaHistochemical and Electron Microscopic Study. Arch Dermatol. 1974;109(1):40-48. doi:10.1001/archderm.1974.01630010020004