Vagina: Basic Principles and Pathologies

Vagina: Basic Principles

• The canal leading to the cervix is lined with non-keratinizing squamous epithelium.
• The vaginal mucosa is made up of non-keratinizing squamous epithelium.

Adenosis

• Columnar epithelium persists in the upper vagina during development.
• Squamous epithelium from the vagina's lower third replaces the columnar epithelium in the upper two-thirds during development.
• Squamous epithelium is derived from the urogenital sinus.
• Columnar epithelium is derived from the Müllerian ducts.
• Exposure to diethylstilbestrol (DES) in utero increases the incidence of adenosis.

Clear Cell Adenocarcinoma

• A malignant proliferation of glands with clear cytoplasm.
• A rare but serious complication of DES-associated vaginal adenosis.
• It is feared due to its rarity.

Embryonal Rhabdomyosarcoma

• A rare malignant mesenchymal proliferation of immature skeletal muscle.
• Commonly presents in children under 5, often as a grape-like mass protruding from the vagina or penis.
• Known as sarcoma botryoides.
• Rhabdomyoblasts are characteristic cells with cytoplasmic cross-striations.
• These are positive for desmin and myogenin upon immunohistochemical staining.

Vaginal Carcinoma

• Arises from squamous epithelium lining the vaginal mucosa.
• Often associated with high-risk human papillomavirus (HPV).
• Vaginal intraepithelial neoplasia (VAIN) is a precursor lesion.
• Cancer from the lower third of the vagina spreads to inguinal lymph nodes.
• Cancer from the upper two-thirds spreads to regional iliac lymph nodes.
• Excessive DES use led to the cessation of use due to the discovery of this complication and others.

Explore the anatomy and developmental aspects of the vagina, including the significance of adenosis and the implications of exposure to diethylstilbestrol (DES). This quiz covers clear cell adenocarcinoma and embryonal rhabdomyosarcoma, highlighting their clinical relevance and characteristics. Test your understanding of these important concepts in gynecological health.