What does VIN mean?
The term VIN refers to precancerous lesions of the vulva (Vulvar Intraepithelial Neoplasia).
A percentage of vulvar cancers (approximately 40%) is causally related to oncogenic types of HPV.
These precancerous lesions that precede cancer are referred to as “HPV-related VIN lesions.”
HPV 16 is the most common causal factor.
How are HPV-related VIN lesions classified?
In the past, they used to be classified as VIN 1, 2, 3. The classification system has changed since 2004, however, and the term VIN today describes only high-grade lesions (VIN2, 3).
Low-grade lesions are referred to as simple condylomatous (wart-like) lesions.
Are HPV-related VIN lesions visible?
Most of these lesions are visible to a naked eye examination. Their color varies. They are usually gray or white. Sometimes, however, they are shades of red or brown.
HPV-related VIN lesions cause no symptoms. Itching is reported in a few cases. Quite often, they are discovered accidentally by the patient or the doctor. Patients frequently report a history of genital warts or a CIN history.
How are the lesions diagnosed?
The vulvar area is examined under magnification (optionally with the colposcope), as the entire lower genital tract and anal area should be examined.
Diagnosis always requires a biopsy and histological examination.
How are HPV-related VIN lesions treated?
As mentioned above, only high-grade lesions (VIN 2, 3) are considered VIN lesions. Treatment is recommended for these lesions.
No treatment is recommended for subclinical condylomatous lesions, which used to be referred to as VIN1.
What does treatment entail and what are the criteria?
The following treatments are currently recommended:
- Surgical removal of lesions: Surgical removal is necessary even when there is the slightest suspicion of an invasive vulvar carcinoma. It is also required in cases where the VIN lesions are in vulvar areas covered with hair, because the affected epithelium in these areas goes down deep around the hair follicles, and cannot be destroyed with a surface laser.
- Ablation of lesions with carbon dioxide laser: This method is considered the best for the destruction of the lesions. It is implemented by your doctor only in vulvar areas with no hair (for the reason mentioned above). Healing is very good, as is the cosmetic result.
- Imiquimod cream: It was first used as an adjunct treatment to the previous treatments in order to decrease recurrences. It is also administered in selected cases as a first-line treatment (small lesions, that have recentlyappeared in young women), with close follow-up.
Do the lesions recur after treatment? Is follow-up necessary?
Recurrences of the lesions after treatment are very common. Therefore, close follow-up is required.