This explanation is a follow-up to the patient information leaflet 'Monitoring Anal Intraepithelial Neoplasia'.
Background
: AIN (Anal Intraepithelial Neoplasia) refers to a change in the mucous membrane in and around the anus. AIN involves abnormal mucous membrane cells. These abnormal cells can potentially develop into anal cancer, and for this reason, AIN is considered a precursor to anal cancer. The detection of AIN does not mean that you have or will develop anal cancer. It is assumed that only a minority of patients with AIN will eventually develop anal cancer. Unfortunately, it is difficult to predict who and what percentage of patients will ultimately develop anal cancer. To reduce the risk of anal cancer, treatment for high-grade AIN (AIN 2 and 3) is recommended. There are three precursors of AIN:
AIN 1
For AIN 1 (low grade), no treatment is recommended. The condition can disappear spontaneously. You will be called back after a year to be checked for AIN.
AIN2 and AIN3
This is collectively called high-grade AIN. We recommend that you undergo treatment.
Treatment:
There are various treatments for AIN. Based on current knowledge, electrocoagulation (burning) and/or treatment with cream have been chosen. A study at the AMC, which investigated the effectiveness of various treatments for AIN, has shown that treatment depends on the location of the AIN. Below, you can read which treatment applies to you.
If the AIN is located inside your anus (intra-anal),
we will treat you with electrocoagulation (burning). In this treatment, the mucous membrane containing AIN is burned away using a type of ballpoint pen with a small electric ball. To ensure effective treatment, the site of the lesion is anesthetized with lidocaine. You may still experience a warm sensation. After the treatment, a superficial "burn" will develop that heals within about 1 to 2 weeks.
How often do you need treatment?
Electrocoagulation is performed in one or two sessions, 12 weeks apart. If abnormalities remain visible 12 weeks after the last treatment, further biopsies will be taken to assess the treatment's success.
After the treatment:
The skin or mucous membrane may bleed slightly after the treatment, which can last one to several days. You will be given an absorbent bandage to prevent any blood from staining your clothing. Blood may be visible in stool or on toilet paper for a few days. This is normal. Only in the event of heavy bleeding should you contact your examiner. If you experience pain, you can take paracetamol. For maximum effect, it is recommended to take one to two 500 mg tablets up to four times a day. If the pain does not subside quickly enough, we can also prescribe a soothing cream and/or a pain-relieving lidocaine ointment. It is recommended to avoid passive anal sex for one week after the treatment. It is also important not to strain during bowel movements and to ensure soft stools. This is to help the wounds heal faster. If you experience prolonged anal bleeding or other anal complaints, we advise you to avoid passive anal sex until these complaints have subsided and to contact the research team. You can resume your normal activities on that day. Please consult your researcher if you have any questions. If
the AIN is located on the outside of your anus (perianal),
you will be treated with imiquimod cream (Aldara) for 16 weeks. This cream activates the immune system. Possible side effects of this cream include local irritation, fatigue, and flu-like symptoms.
Is the AIN located both inside and outside your anus?
We will then treat you with a combination of the above treatments.
Alternatives:
Depending on your personal situation, your practitioner may choose a different treatment. For example, freezing, 5-fluorouracil cream (Efudix), or treatment with highly saturated trichloroacetic acid (TCA) may be chosen.
Follow-up after adequate treatment:
You will remain under constant surveillance for AIN. Depending on the grade of the AIN, we will see you again after six months or after one year for a check-up.
Studies on the treatment and prevention of AIN:
1) Vaccination against human papillomavirus (HPV) type 16 as a treatment (VACCAIN-T): A treatment currently being investigated is therapeutic vaccination against HPV-16. AIN can be caused by different types of HPV. More than 100 different types are known, but type 16 is the most common cause of AIN. You may be eligible for this study at the AMC, where we vaccinate against HPV type 16. A requirement for participation is that HPV type 16 is present in the biopsy taken from you. If you are eligible for this study, the researcher will provide you with further information.
2) Vaccination against HPV to prevent new AIN (VACCAIN-P): In addition to the vaccination treatment study mentioned above, a second study is underway on HPV vaccination to prevent new AIN. You are eligible for this study if your high-grade AIN has recently been successfully treated. This study investigates the vaccine Gardasil, which is effective in preventing HPV types 6, 11, 16, and 18. If you are eligible for this study, the researcher will provide you with further information. This study will take place at the AMC, Onze Lieve Vrouwe Gasthuis, and the DC Klinieken Oud Zuid. To
schedule or
reschedule an appointment, please call the dermatology outpatient clinic.
Tel: 020-5662530. The outpatient clinic is located in building A, floor 0 of the AMC. (A0) |
