GANGLIOCYTIC PARAGANGLIOMA OF THE DUODENUM - REPORT OF A CASE WITH IMMUNOCYTOCHEMICAL AND ULTRASTRUCTURAL INVESTIGATION

A case of gangliocytic paraganglioma is reported in a 70-year-old fema le presenting as a polypoid tumor of the second portion of the duodenu m. Immunohistochemical and ultrastructural features of the tumor indic ate that gangliocytic paraganglioma of the duodenum (GPD) represents a n unique tumor originating from the neuroectodermal derivative exhibit ing dual phenotypic expression toward paraganglionic and epithelial (n euroendocrine) cells. These findings correlate well with the literatur e and it is further suggested that GPD belongs to the histopathologic spectrum of tumors derived from the neural crest. The findings offer a plausible explanation for histogenetic genetic possibilities of the o ccurrence of pure epithelial tumors (i.e., carcinoid-like tumors) in t he paraganglionic systems. The patient remains with no evidence of dis ease 4 years following a simple polypectomy.