Metro Colon Rectum - Proctology Corner – Anal Warts

Condyloma, anal intraepithelial neoplasia and anal cancer are how proctologists describe the transition from benign anal warts to malignant anal cancer in the anal canal.  The progression and regression of disease occurs over time in the skin and mucous membranes spanning the anal canal and is caused by genetic mutations in the cells secondary to viral infections like human papilloma virus (HPV).  HPV is the most common sexually transmitted infection in the United States and effects the cervix, vagina, vulva, penis and anus in men and women.  HPV, specifically subtype 16 and 18, has been implicated in cancer of the anus, especially in cases of HIV co-infection with or without immune suppression.

As the cells of the anal canal are exposed to repeated viral infection, they become more unstable.  Over time this instability can lead to mutations which can cause cancer at a cellular level.  These mutations occur at the cellular level across the entire anal canal and can happen after the initial infectious period has passed.  When the immune system is healthy the body can reverse some of these changes but with repeated infections the immune system can be overwhelmed. 

The treatment for anal warts is multi-factorial and focuses on risk reduction and early detection with eradication.  Risk reduction focuses on decreasing exposure to HPV and managing other immune-compromising conditions: avoiding unprotected intercourse, immunization versus HPV (ex. Gardasil-9), and optimized anti-retroviral therapy for HIV for example.  Early detection with eradication involves anoscopy which is the process in which a clinician examines the anal canal in a specifically designed procedure suite or an operating room.  During the procedure, if irregular cells are identified, the irregular cells are biopsied and fulgurated (destroyed by a high-frequency electric current).  Following the procedure, a trained pathologist stains the tissue and identifies any cellular mutations that might indicate cellular progression to cancer.

Methods of risk reduction are a continuous process.  Detection and eradication occur three to four times each year based on the level of cellular mutations identified.  As more mutations are identified, more frequent surveillance is needed.  In between treatments, the clinician may prescribe topical immune modulators to the anal canal to stimulate the host immune cell to migrate to the anal canal and address the cellular mutations.

While the progression of benign anal warts to malignant anal cancer is a concerning process that must be followed closely, the progression occurs over time.  Patients armed with appropriate risk reduction and scheduled detection and eradication treatments can control the disease and significantly reduce risk.