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Anal Intraepithelial Neoplasia (AIN)

Anal intraepithelial neoplasia (AIN), anal dysplasia, low-grade (LSIL) and high-grade squamous intraepithelial lesion (HSIL) are all terms to describe abnormal cells in the anal canal. This may be found after an anal pap smear or on a biopsy of your anal area. The pathologist will grade the lesion as high-grade or low-grade. High-grade lesions are considered pre-cancerous and should be investigated and treated further. However dysplasia is not cancer and is treated very differently. Patients with high-grade lesions need close follow-up and any new lesions should be treated promptly.

What are the symptoms of AIN or anal dysplasia?

Patients may experience itching, bleeding, mucous discharge, feeling of a lump or a mass in the anal area or no symptoms at all.

What causes AIN or anal dysplasia?

AIN or anal dysplasia is caused by human papilloma virus (HPV) infection. AIN is similar to cervical intraepithelial neoplasia or CIN, which also originates from HPV. CIN and AIN can develop into cervical and anal cancer respectively.

Certain people are at increased risk for anal dysplasia including patients with HPV infections, patients with a history of anal intercourse, HIV positive patients, cigarette smokers, patients with a weakened immune system due to certain medications for conditions such as RA, IBD, or solid organ transplant.

What is the treatment of AIN or anal dysplasia?

Once you have anal dysplasia, it rarely disappears. Progression to anal cancer occurs in less than 5% of patients with dysplasia, but the risk of progression to cancer seems to be higher in HIV-positive patients.

Dr. Zaghiyan recommends close follow-up long term to detect recurrence, persistence, or progression to anal cancer. Physical exams may be performed at 3-6 month intervals depending on your particular clinical condition.

Treatments include topical creams such as imiquimod (Aldara) or topical 5-fluorouracil (5-FU), and/or a variety of procedures including exam under anesthesia (EUA) to identify, destroy or excise the lesion or targeted therapy with high resolution anoscopy (HRA). Surgery is usually performed as outpatient or same-day surgery. Time needed off work may be anywhere from 1 day to weeks depending on your pain tolerance and the extent of the area treated.

Make an appointment with Dr. Zaghiyan in her office in Los Angeles for a thorough evaluation and recommendations for the best treatment for your specific condition.



Cedars Sinai
8737 Beverly Blvd #101
West Hollywood, CA 90048
Phone: 310-289-9224