title: Secondary erythrocytosis associated with schwannoma in a dog.
abstract: An 11-year-old, spayed female mixed-breed dog showed clinical signs of right forelimb lameness and pain by palpation around the neck. Radiography and computed tomography (CT) revealed an extradural mass at the 6th and 7th cervical vertebrae, which compressed the spinal cord. The mass was surgically removed and histopathologically diagnosed as schwannoma. The dog recovered her normal gait after hemilaminectomy and removal of the mass. Ten months after the surgery, the tumor recurred with absolute erythrocytosis and was surgically removed again. This removal temporarily resolved the erythrocytosis with a decrease in plasma erythropoietin (EPO) concentration. EPO protein was detected immunohistochemically in the tumor cells. Erythrocytosis in this dog may be caused by ectopic EPO produced in the schwannoma tissues.
authors.affiliation: Laboratory of Veterinary Surgery, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Yamauchi
authors.forename: Tamiko
authors.initials: T
authors.lastname: Ohta
authors.forename: Taro
authors.initials: T
authors.lastname: Okada
authors.forename: Manabu
authors.initials: M
authors.lastname: Mochizuki
authors.forename: Ryohei
authors.initials: R
authors.lastname: Nishimura
authors.forename: Satoru
authors.initials: S
authors.lastname: Matsunaga
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nakayama
authors.forename: Kunio
authors.initials: K
authors.lastname: Doi
authors.forename: Nobuo
authors.initials: N
authors.lastname: Sasaki
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D004921:Erythropoietin / Q000097:blood; D005260:Female; D006400:Hematocrit / Q000662:veterinary; D007150:Immunohistochemistry / Q000662:veterinary; D009442:Neurilemmoma / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery / Q000662:veterinary*; D010524:Peripheral Nervous System Neoplasms / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery / Q000662:veterinary*; D011086:Polycythemia / Q000150:complications / Q000473:pathology / Q000662:veterinary*; D011859:Radiography; D013126:Spinal Nerve Roots / Q000000981:diagnostic imaging
chemical_list: D004921:Erythropoietin