1. Screening for anal dysplasia associated with human papillomavirus;Mathews WC;Top HIV Med.,2003
2. WHO Classification of Tumours. Pathology and genetics of digestive system of tumours;Fenger C,2000
3. Surveillance Epidemiology and End Results, SEER
4. Cancer statistics;emal A;CA Cancer J Clin,2004
5. Anorectal sexually transmitted infections in men who have sex with men: special considerations for clinicians;Goldstone SE;Clin Colon Rectal Surg,2004