Multiple neuropeptide immunoreactivities in a renin-producing human paraganglioma.

A case of a renin-producing paraganglioma of adrenal origin with metastases to the retroperitoneal area, paravaginal area, and the ovary is reported with immunohistochemical findings indicating expression of multiple neuropeptide immunoreactivities. The patient was 23 years old at the time of diagnosis, and died from metastatic spread of the tumor 7 years later. Tumor tissue was examined by light microscopy, indirect immunohistochemistry, and electron microscopy. The tumor tissue investigated contained several cells exhibiting opioid peptide-like immunoreactivities (i.e., enkephalin and dynorphin-like immunoreactivity [LI]). A lower number of cells displayed neuropeptide Y-, galanin-, somatostatin-, neurotensin-, substance P-, peptide histidine-isoleucine-, cholecystokinin-, renin-, and calbindin-LI. To the authors' knowledge, galanin, dynorphin, peptide histidine-isoleucine, cholecystokinin, and calbindin have not been reported previously to occur in paraganglioma, and renin has been reported to occur very rarely. A review of recent literature suggest that enkephalin-, neuropeptide Y-, and somatostatin-like immunoreactivities may be useful as diagnostic markers for paragangliomas.