CTN 216: Argon plasma coagulation for anal dysplasia in MSM

About The Study

This study evaluates the safety and efficacy of a new non-surgical treatment called Argon Plasma Coagulation (APC) for pre-cancerous anal lesions, classified as moderate to severe Anal Intraepithelial Neoplasia in MSM.

The study will evaluate how many APC treatments are needed in order for anal neoplasia to disappear or diminish over two years. It will also assess how effective APC treatment is in decreasing the viral load of anal Human Papilloma Virus 16 (HPV 16) in MSM with anal lesions. HPV 16 is the type of HPV that is more likely to be associated with moderate to severe anal neoplasia.

This is a pilot study aiming to recruit 20 adult MSM between 18 and 65 years of age at Notre-Dame Hospital and Royal Victoria Hospital in Montreal. Eligible participants will have been diagnosed with persistent moderate to severe AIN as confirmed by two biopsies at least 4 months apart in the previous year.

Currently, there is a three-year observational study about the detection of Human Papilloma Virus (HPV) and anal dysplasia involving 60 participants taking place at Notre-Dame Hospital. Researchers are hoping that participants in this three-year study may consider participating in this particular trial.

About The Disease

The risk of developing anal cancer in HIV-infected MSM is higher than in the general population. One of the main causes of anal cancer is the Human Papilloma Virus (HPV). HPV can infect the skin of the anus and cause pre-cancerous changes (changes that may lead to cancer) called dysplasia or intraepithelial neoplasia, which can be detected by using High-Resolution Anoscopy (HRA) and biopsy. Mild dysplasia is closer to normal cells than moderate to severe dysplasia. Although abnormalities identified as moderate to severe AIN are more like cancerous cells and may lead to cancer, it is not cancer itself.

Study Approach

While it is possible to identify pre-cancerous anal lesions, there is no effective treatment for severe cases of AIN at the present time. Few non-surgical treatments are available for this condition, and researchers are looking at APC as a possible new treatment method for severe AIN.

Argon Plasma Coagulation (APC) is a non-surgical treatment that involves applying an electrical current to a gas (the Argon gas becoming the Argon Plasma), which is then conducted to the lesion through a tube without touching the lesion. APC has the effect of destroying the superficial layers (about 1 to 3 mm deep) of the tissue. This treatment method has been studied in people with different medical conditions in the stomach, intestine or rectum. However, it has never been studied to treat AIN. Efficacy and side effects of this treatment for anal lesions are unknown.

Results

Only three participants responded to the first treatment and remained HSIL-free for the duration of the study. One of the 20 participants never responded to treatment. In total, 13 participants ended the study HSIL-free. The primary side effect reported was pain during the procedure and within one week post-treatment. Dr. Pokomandy and her team concluded that APC is comparable to other anal HSIL treatment modalities in efficacy, safety, and rates of recurrence in men having sex with men living with HIV, but that the cost of this treatment remains a drawback. Effective pain management during and following APC is necessary.