1Larry P Tilley, Francis W K Smith Jr. Blackwell's five minute Veterinary consult: canine and feline[M]. 4th ed. Iowa: Blackwell, 2007: 24.
2Joanna Morris, Jane Dobson. Small animal oncology[M]. Iowa: Blackwell, 2001 : 135.
3Stephen J. Withrow, David M Vail. Small Animal Clinical Oncology[M]. 4th ed. St Louise: Sauders Elsevier, 2006 : 503-510.
4Vail D M, Withrow S J, Schwarz P D, et al. Perianal adenocarcinoma in the canine male: a retrospective study of 41 cases [J]. Journal of the American Animal Hospital Association, 1990,26(3): 329-334.
5Pisani G, Millanta F, Lorenzi D, et al. Androgen receptor expression in normal, hyperplastie and neoplastic hepatoid glands in the dog[J]. Research in Veterinary Science, 2006,81(2) : 231-236.
6Pakhrin B, Kang M S, Bae I H, etal. Retrospective study of canine cutaneous tumors in Korea [J]. J Vet Sei, 2007, 8(3) 229- 236.
7Mukaratirwa S, Chipunza J, Chitanga S, etal. Canine cutane ous neoplasms: prevalence and influence of age, sex and site on the presence and potential malignancy of cutaneous neoplasms in dogs from Zimbabwe[J]. J S Aft Vet Assoc, 2005, 76(2) :59-62.
8Chatelain D, Mokrani N, Flejou J F. Anal and anal margin tumors[J]. AnnPathol, 2007, 27(6): 459-4?5.
9Toms N, Bicknell C, Harrison R. Colo anal intussusception in an adult: case report and review of the literature [J]. Int J Clin Pract, 2009, 63(1) :175-176.
10Longacre T A, Kong C S, Welton M L. Diagnostic problems in anal pathology[J]. Adv Anat Pathol, 2008, 15 (5)1263- 278.
