Precancerous conditions of the vagina

Precancerous conditions of the vagina are changes to vaginal cells that make them more likely to develop into cancer. These conditions are not yet cancer. But if they aren’t treated, there is a chance that they will become vaginal cancer. It can take about 5 to 10 years for precancerous conditions to progress to vaginal cancer, but sometimes it happens in less time.

Vaginal intraepithelial neoplasia

Vaginal intraepithelial neoplasia (VAIN) is the most common precancerous condition of the vagina. Abnormal changes occur in the cells in the inner surface layer (called the epithelium) of the vagina. VAIN is more often seen in the upper part of the vagina and is often multifocal, which means it’s in more than one place. VAIN often occurs together with cervical intraepithelial neoplasia (CIN) and is thought to have a similar cause. It may spread from nearby areas of CIN or occur separately.

VAIN is categorized based on how abnormal the cells in the epithelium are (called dysplasia):

  • VAIN 1 means that the epithelium is mildly abnormal. This is called mild dysplasia.
  • VAIN 2 means that the epithelium is moderately abnormal. This is called moderate dysplasia.
  • VAIN 3 means that the epithelium is severely abnormal and is considered a premalignant lesion. This is called severe dysplasia or carcinoma in situ. VAIN 3 usually occurs when CIN 3 (severe dysplasia of the cervix) is present.

VAIN can also be classified as low grade or high grade. Low-grade VAIN means that the cells look almost like normal cells. In low-grade VAIN, the abnormal cells tend to grow slowly and they are less likely to change into cancer cells. High-grade VAIN means that the cells look less normal or more abnormal. High-grade VAIN involves either the outer third of the mucosa or the entire thickness of the epithelium.

Risk factors

The following risk factors increase your chance of developing VAIN:

  • a history of human papillomavirus (HPV) infection
  • a history of CIN or cervical cancer


Precancerous changes in the vagina often do not cause any signs or symptoms.


If your doctor thinks you might have VAIN, you will be sent for tests. An abnormal Pap test result is often the first sign that some cells in the cervix or vagina are abnormal. Tests used to diagnose VAIN include:


In VAIN 1, the mildly abnormal cells often return to normal without any treatment. In VAIN 2, the moderately abnormal cells likely won’t return to normal, so treatment is usually started right away. In VAIN 3, the severely abnormal cells are more likely to develop into vaginal cancer, especially if they are not treated.

Treatments for VAIN include:

  • observation (watching for changes)
  • topical estrogen therapy
  • topical chemotherapy using 5-fluorouracil (5-FU) cream
  • imiquimod (Aldara) cream (a drug that creates an immune response in the area of abnormal tissue)
  • laser surgery
  • surgery to remove the abnormal area and some normal tissue around it (called a wide surgical excision) or to remove part of the vagina (called a partial vaginectomy)

Expert review and references

  • American Cancer Society. Vaginal Cancer. 2014:
  • Klopp AH, Eifel PJ, Berek JS, Konstantinopoulos PA . Cancer of the cervix, vagina and vulva. DeVita VT Jr, Lawrence TS, Rosenberg SA. Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 72:1013-1047.
  • Levine DA, Dizon DS, Yashar CM, Barakat RR, Berchuch A, Markman M, Randall ME. Handbook for Principles and Practice of Gynecologic Oncology. 2nd ed. Philadelphia, PA: Wolters Kluwer; 2015.

Medical disclaimer

The information that the Canadian Cancer Society provides does not replace your relationship with your doctor. The information is for your general use, so be sure to talk to a qualified healthcare professional before making medical decisions or if you have questions about your health.

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