Obstet Gynecol Sci.  2024 Mar;67(2):169-185. 10.5468/ogs.23274.

Vulval premalignant lesions: a review article

• Gupta S
• Ahuja S
• Kalwaniya DS
• Shamsunder S
• Solanki S

• KMID: 2553425
• DOI: http://doi.org/10.5468/ogs.23274

Abstract

Vulvar intraepithelial neoplasia (VIN) is a noninvasive squamous lesion that is a precursor of vulvar squamous cell cancer. Currently, no screening tests are available for detecting VIN, and a biopsy is performed to confirm the clinical diagnosis. Despite sharing many risk factors with cervical intraepithelial neoplasia, the diagnosis of VIN is poses challenges, contributing to its increasing prevalence. This study aimed to analyze the underlying risk factors that contribute to the development of VIN, identify specific populations at risk, and define appropriate treatment approaches. Differentiated VIN (dVIN) and usual VIN (uVIN) are the classifications of VIN. While dVIN is associated with other vulvar inflammatory disorders, such as lichen sclerosis, the more prevalent uVIN is associated with an underlying human papillomavirus infection. Patients with differentiated VIN have an increased risk of developing invasive malignancies. Few effective surveillance or management techniques exist for vulvar intraepithelial neoplasia, a preinvasive neoplasm of the vulva. For suspicious lesions, a thorough examination and focused biopsy are necessary. Depending on the specific needs of each patient, a combination of surgical and medical approaches can be used.

Keyword

Vulva; Vulvar intraepithelial neoplasia; Vulvar dysplasia; Vulvar lesions; Vulvar pathology

Figure

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  Fig. 1 Commonly affected sites on the vulva are the labia majora and minor, as well as the fourchette.

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  Fig. 2 Elevated and finely delineated acetowhite epithelium after the application of 3–5% acetic acid, corresponding to VHSIL. VHSIL, vulvar high-grade squmous intraepithelial lesions.

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  Fig. 3 The three vulvar rings: outer, iddle and inner vulvar ring.

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  Fig. 4 Histological sections reveal acanthosis, along with atypical koilocytosis in the upper layers. Mild atypia and mitotic activity limited to the lower third of the epithelium are suggestive of VIN 1 (×100 magnification). VIN, vular intraepithelial neoplasia.

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  Fig. 5 (A) Histological sections reveal acanthosis with nuclear atypia and increased mitotic activity involving the lower two-thirds of the epithelium, suggestive of VIN 2 (×400 magnification). (B) Immunohistochemistry reveals block positivity for p16 (×400 magnification). VIN, vulvar ntraepthelial neoplasia.

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  Fig. 6 (A) Histopathological sections reveal acanthosis with loss of polarity, full thickness nuclear atypia, and increased mitotic activity, suggestive of VIN 3 (×400 magnification). (B) Immunohistochemistry reveals block positivity for p16 (×400 magnification). VIN, vulvar ntraeithelial neoplasia.

Reference

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