neuropeptide-y and Retroperitoneal-Neoplasms

It has been reported that vasoactive intestinal peptide (VIP)-producing tumors accompanied by watery diarrhea, hypokalemia, and achlorhydria (WDHA) syndrome often produce multiple hormones biochemically and immunohistochemically.. The authors examined the distribution of several peptides--VIP, peptide histidine methionine (PHM), neuropeptide Y (NPY), methionine-enkephalin (M-EK), somatostatin (SS), substance-P (Sub-P), corticotropin-releasing hormone, and tyrosine hydroxylase--with immunohistochemical studies and an in situ hybridization method in three ganglioneuroblastomas with WDHA syndrome. All patients had an extremely elevated plasma level of VIP.. Peptides examined immunohistochemically in the tumor were all detectable in ganglionic cells and some neurites. The coexistence of those peptides was observed with serial section staining. The presence of messenger RNA of VIP/PHM-27, NPY, and SS was detectable in the cytoplasm of the tumor cells with the in situ hybridization.. It was shown that multiple genes of peptides are expressed simultaneously and translated to proteins in those tumors.

Topics: Child, Preschool; Corticotropin-Releasing Hormone; Enkephalin, Methionine; Female; Ganglioneuroma; Gene Expression Regulation, Neoplastic; Humans; In Situ Hybridization; Infant; Male; Neuropeptide Y; Peptide PHI; Retroperitoneal Neoplasms; Somatostatin; Substance P; Tyrosine 3-Monooxygenase; Vasoactive Intestinal Peptide; Vipoma

A patient with a malignant extraadrenal retroperitoneal paraganglioma had elevated levels of immunoreactive neuropeptide Y (NPY) in the peripheral blood (5988 pg/ml; normal, 123 +/- 30 pg/ml [mean +/- standard error of the mean]). A 6-month course of chemotherapy allowed surgical removal of the previously unresectable primary tumor. Postoperatively, the plasma NPY level initially fell to 1089 pg/ml; continued chemotherapy caused an additional decrease to 440 pg/ml. Four months after surgery, the plasma NPY level increased to 940 mg/ml, coincident with hepatic metastases. This case is the first report of a NPY-secreting clinically nonfunctional malignant extraadrenal paraganglioma. Determination of circulating NPY levels may be useful in the diagnosis and follow-up of patients with neuroendocrine tumors.

Topics: Female; Humans; Middle Aged; Neoplasm Invasiveness; Neuropeptide Y; Paraganglioma, Extra-Adrenal; Peritoneal Neoplasms; Retroperitoneal Neoplasms