Vaginal precancerous lesions (VaIN)

What are VaINs?

VaINs are lesions with abnormal cells inside the vaginal epithelium. VaIN are the initials of the words Vaginal Intraepithelial Neoplasia.

Vaginal lesions are distinguished into:

  • low-grade (LSIL/VaIN1) and
  • high-grade (HSIL/VaIN2,3)

The classification is similar to the lesions on the cervical squamous epithelium.

The term low-grade signifies the good behavior of the lesions of this group, which are usually simple condylomatous (warty) infections and subside on their own.

The term high-grade signifies the possibility of these lesions evolving into invasive vaginal cancer.

How are they diagnosed?

Most of the VaIN lesions are discovered during the colposcopy which follows an abnormal Pap test.

The doctor detects the lesions on the vagina after first applying an acetic acid solution and then the lugol iodine solution. The next step is to take biopsies in order to ascertain the severity of the lesions with a histologic examination.

Which lesions require treatment?

Low-grade lesions (LSIL/VaIN1) usually subside without any treatment.

In young women, VaIN2 lesions should be monitored for a certain period because a significant percentage of them subside automatically.

Even though the physical history of carcinogenesis in the vagina has not been fully explained, it is internationally accepted that high-grade lesions (HSIL/VaIN2, 3), and in particular VaIN3, must be treated.

How are high-grade lesions (HSIL/VaIN2, 3) treated?

There are two methods for treating the lesions:

  • Laser ablation of the lesions
  • Excision of the lesions

Ablation is performed when there is no suspicion that invasive carcinoma on the vaginal wall may have been missed. When there is any suspicion of invasive cancer, the removal of the lesions is preferred.

Can vaginal precancerous lesions appear in women who have had their uterus removed?

Women with a history of high-grade cervical lesions or cervical cancer have a risk of precancerous vaginal lesions and vaginal cancer after a hysterectomy.

Follow-up is recommended for these women.

What is the effect of smoking on VaIN lesions?

Smoking is considered to have an exacerbating role and quitting is recommended. Smoking is believed to increase the possibility of carcinogenesis or recurrence of the lesions after treatment.