Vulva - Pathology

VULVA

Non-Neoplastic Disorders

•      Lichen sclerosis is caused by epidermal thinning and dermal changes which cause pale skin in postmenopausal women. There is a small risk of progression to squamous cell carcinoma (SCC).

•      In lichen simplex chronicus, a chronic scratch/itch cycle produces the white plaques seen clinically. These plaques are characterized microscopically by squamous cell hyperplasia and dermal inflammation.

Infections

•      Human papillomavirus (HPV) causes warty lesions (condylomata acuminata) and precursor dysplastic lesions of squamous cell carcinoma called vulvar intraepithelial neoplasia (VIN). Vulvar HPV is commonly subtype 6 and 11 and therefore has low oncogenic potential.

•      Herpes simplex virus (HSV). Most cases of vulvar herpes are caused by HSV-2. Painless vesicles progress to pustules and painful ulcers.

•     Syphilis is a sexually transmitted disease caused by Treponema pallidum. The primary lesion is a chancre, a painless ulcer that does not scar after healing.

•        Molluscum contagiosum is a viral disease caused by a DNA poxvirus. It pres-ents as smooth papules and has characteristic cytoplasmic viral inclusions.

•         Bartholin gland abscess is a polymicrobial infection requiring drainage or excision.

Tumors

•         Papillary hidradenoma is a benign tumor of modified apocrine sweat glands of the labia majora or interlabial folds. It occurs along the milk line and may ulcerate, mimicking carcinoma. Papillary hidradenoma is histologically simi-lar to an intraductal papilloma of the breast.

•         Extramammary Paget disease of the vulva usually involves the labia majora, and it causes an erythematous, crusted rash that is characterized microscopi-cally by intraepidermal malignant cells with pagetoid spread. This form of Paget disease is not usually associated with underlying tumor.

•         Squamous cell carcinoma is the most common malignancy of the vulva. The most common form occurs in women age >60. The less common form occurs in younger women with HPV serotypes 16 and 18.

•         Melanoma can occur on the vulva, and must be differentiated from lentigo simplex which is more common.