Vulva

This article addresses the basics of vulva, from a pathologic perspective.

Low grade pre-cancerous lesions (VIN) are typically HPV positive, while high grade pre-cancerous lesions and cancer are less often HPV positive.

Most common malignancy of vulva:

• Invasive squamous cell carcinoma.

Precursor lesion:

• vulvar intraepithelial neoplasia (VIN).

VIN can be divided into:

• Classic VIN, and
• Differentiated VIN.
  • Differentiated VIN is mostly irrelevant as it is basically never seen alone, i.e. it usually accompanies cancer.

Classic VIN

Epidemiology

• Classic VIN, like CIN, is associated with HPV and seen in younger women.

General

• Classic VIN is graded like cervical pre-cancerous lesions:
  • VIN I.
    • Not common.
  • VIN II.
    • Not common.
  • VIN III.
    • Commonly seen.

DDx:

• Condyloma (genital wart).
  • Most caused by HPV.

Micro. of classic VIN

• Increased NC ratio.
• Multinucleation.
• Lack of maturation to surface (not very useful -- unlike in the cervix).
• Apical mitoses.

Differentiated VIN

Epidemiology

• Assoc. with lichen sclerosis.
• NOT associated with HPV and seen in older women.

Histology

• NOT graded like classic VIN.
• Acanthosis (thickening of stratum spinosum) + elongation of rete ridges.

IHC for VIN

• Classic VIN: p16+, p53-.
• Differentiated VIN: p16-, p53+.

ASIDE: p16 can be thought of as a poor man's HPV test.

Lichen sclerosus

General

• Pruritis -> leads to scratching.

Microscopic

Features:

• Loss of rete ridges - key feature.
• Severe hyperkeratosis.
• Fibrosis of dermis with loss of adnexal structures
• Inflammation - often with eosinophils.

Bartholin cyst

General

• Common.

Micro

• Cyst with squamous or urothelial epithelium.

See also

• Gynecologic pathology.
• Uterus.
• Cervix - cervical intraepithelial neoplasia.
• Vagina.
• Anus - anal intraepithelial neoplasia.