IMMUNOHISTOCHEMICAL DEMONSTRATION OF CHROMOGRANIN-A, CHROMOGRANIN-B, AND SECRETOGRANIN-II IN EXTRAADRENAL PARAGANGLIOMAS

Twelve sympathetic and 14 parasympathetic extra-adrenal paragangliomas were investigated immunohistochemically with antibodies against chrom ogranin A, chromogranin B, and secretogranin II. In sympathetic paraga ngliomas chromogranin A was found in 12/12 and chromogranin B in 11/12 tumors in almost all chief cells (the remaining tumor was focally chr omogranin B positive), whereas secretogranin II was immunolocalized in the majority of chief cells in 5/12, in a focal distribution in 3/12, and only in a few scattered tumor cells in 3/12 cases. One case showe d no secretogranin II immunoreactivity. In parasympathetic paraganglio mas both chromogranin B and secretogranin II immunoreactivity was demo nstrated in the majority of chief cells of all 14 tumors investigated. Chromogranin A showed a strong immunostaining in 2/14 cases; in 12 tu mors chromogranin A was found in only a few chief cells or was complet ely absent. It is concluded that sympathetic and parasympathetic parag angliomas show a divergent expression of chromogranins/secretogranins that apparently reflects the different histogenetic origins of these t umors.