Syringocystadenoma papilliferum. A plasmacytotropic tumor.

Seven cases of syringocystadenoma papilliferum were studied by immunohistochemical methods for the presence of IgG, IgA, IgM, and secretory component in tumor epithelial cells and IgG, IgA, and IgM in plasma cells underlying the tumor epithelium. Six of seven cases showed IgA positivity within epithelial cells, one case showed faint intraepithelial IgG staining, and none stained for IgM. Four of five cases were positive for secretory component. The plasma cells were predominantly of the IgG and IgA class. These findings suggest that the association of plasma cells with this tumor is a consequence of epithelial attraction via a mechanism similar to that utilized by glands of the normal secretory immune system.