title: Mammary gland tumors in a male Cocker Spaniel.
abstract: BACKGROUND
  Mammary gland tumors are the most common tumors in sexually intact female dogs; however, they are rare in male dogs. This study was conducted to investigate the relationship between sexual hormones and mammary gland tumors in a male dog.
  
  
  METHODS
  A 13-year-old, intact male Cocker Spaniel presented to the Veterinary Teaching Hospital of Kangwon National University, Republic of Korea, with an acute right ruptured caudal abdominal mass. Physical examination revealed a 14 × 14 cm ruptured mass in the right caudal abdomen, as well as a 1.5 × 1.5 cm mass in the first right mammary gland. The estrogen and progesterone concentrations in serum were within normal levels. Total mastectomy was done on the right side mammary glands. Following surgery, the site was fully recovered; however, a mass that had grown to 2 × 2 cm was found in the left fifth mammary gland and a testis tumor was also found over the period of 4 months. Mastectomy was performed on the left caudal mammary gland and castration was also performed. After the final surgery, the dog fully recovered. Histopathological examination of all three masses revealed high grade mammary adenocarcinoma in the mammary gland and the testis was diagnosed as Leydig cell adenoma. Immunohistochemical analysis revealed that the estrogen and progesterone receptors were expressed on limited cells in mammary and testis tumors.
  
  
  CONCLUSIONS
  The results of this study suggest that mammary tumors and testes tumors can occur in male dogs without relationship to female sexual hormone.
authors.affiliation: Department of Veterinary Internal Medicine and Institute of Veterinary Science, College of Veterinary Medicine, Kangwon National University, Chuncheon, 200-701, Republic of Korea.
authors.forename: Soon-Chan
authors.initials: SC
authors.lastname: Kwon
authors.affiliation: Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, 151-742, Republic of Korea.
authors.forename: Dae-Young
authors.initials: DY
authors.lastname: Yoo
authors.affiliation: Department of Veterinary Internal Medicine and Institute of Veterinary Science, College of Veterinary Medicine, Kangwon National University, Chuncheon, 200-701, Republic of Korea.
authors.forename: Minho
authors.initials: M
authors.lastname: Ko
authors.affiliation: Department of Anatomy, College of Veterinary Medicine, Kangwon National University, Chuncheon, 200-701, Republic of Korea.
authors.forename: Kwon-Young
authors.initials: KY
authors.lastname: Lee
authors.affiliation: Department of Veterinary Surgery, College of Veterinary Medicine, Kangwon National University, Chuncheon, 200-701, Republic of Korea.
authors.forename: Ho-Hyun
authors.initials: HH
authors.lastname: Kwak
authors.affiliation: Department of Veterinary Radiology, College of Veterinary Medicine, Kangwon National University, Chuncheon, 200-701, Republic of Korea.
authors.forename: In-Chul
authors.initials: IC
authors.lastname: Park
authors.affiliation: Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, 151-742, Republic of Korea.
authors.forename: In-Koo
authors.initials: IK
authors.lastname: Hwang
authors.affiliation: Department of Anatomy, College of Veterinary Medicine, Kangwon National University, Chuncheon, 200-701, Republic of Korea.
authors.forename: Jung-Hoon
authors.initials: JH
authors.lastname: Choi
authors.affiliation: Department of Veterinary Internal Medicine and Institute of Veterinary Science, College of Veterinary Medicine, Kangwon National University, Chuncheon, 200-701, Republic of Korea. jychung77@gmail.com.
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Chung
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D000818:Animals; D004285:Dogs; D004967:Estrogens / Q000097:blood; D007984:Leydig Cell Tumor / Q000556:secondary / Q000601:surgery / Q000662:veterinary*; D008297:Male; D008321:Mammary Glands, Animal / Q000473:pathology; D015674:Mammary Neoplasms, Animal / Q000473:pathology* / Q000601:surgery*; D009919:Orchiectomy / Q000662:veterinary; D011374:Progesterone / Q000097:blood; D056910:Republic of Korea; D013736:Testicular Neoplasms / Q000556:secondary / Q000601:surgery / Q000662:veterinary*; D016896:Treatment Outcome
chemical_list: D004967:Estrogens; D011374:Progesterone
keywords: Adenocarcinoma; Dog; Estrogen receptor; Male; Mammary gland tumor; Progesterone receptor