title: A spontaneous ganglioneuroma in the adrenal medulla of a young Wistar Hannover rat.
abstract: A nodule was observed in the adrenal medulla of a twenty-week-old male Wistar Hannover rat. The nodule was predominantly (over 80%) composed of neural components, with ganglion cells scattered in sparse supporting tissue containing nerve fibers and Schwann cells. In the peripheral area of the tumor, atypical chromaffin cells were also observed. Accumulation of eosinophilic serous fluid was also noted in the stromal tissue. There were neither mitotic figures in the ganglion cells nor necrotic foci. In immunohistochemistry, the ganglion cells were positive for neuronal nuclei (NeuN), and negative for proliferating cell nuclear antigen, S-100, and chromogranin A. There were some NeuN-positive small cells in the peripheral area of the tumor. These findings indicate that this tumor was a ganglioneuroma. This seems to be an extremely rare case, as the spontaneous occurrence of ganglioneuroma in rats is very low, even in two-year carcinogenicity studies.
authors.affiliation: Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., Fukuroi, Shizuoka, Japan. shirai.makoto.v7@daiichisankyo.co.jp
authors.forename: Makoto
authors.initials: M
authors.lastname: Shirai
authors.forename: Kiyonori
authors.initials: K
authors.lastname: Kai
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Makino
authors.forename: Takanori
authors.initials: T
authors.lastname: Maejima
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Kumagai
authors.forename: Tomoe
authors.initials: T
authors.lastname: Tanimoto
authors.forename: Munehiro
authors.initials: M
authors.lastname: Teranishi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sanbuissho
mesh_terms: D000313:Adrenal Medulla / Q000473:pathology*; D000818:Animals; D019439:Chromaffin Cells / Q000473:pathology; D053379:Chromogranin A / Q000378:metabolism; D005729:Ganglioneuroma / Q000473:pathology*; D007150:Immunohistochemistry; D008297:Male; D009474:Neurons / Q000166:cytology / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D053379:Chromogranin A