Notes on Male Genital System Pathology

Hypospadias

  • Definition: A condition where the urethra opens on the inferior surface of the penis.

  • Etymology: "Hypo" means low, indicating the location.

  • Cause: Failure of the urethral folds to close during embryonic development.

  • Embryology Reference:

    • The genital tubercle develops into the glands of the penis or clitoris.

    • Urethral folds must zipper along the inferior surface to form a closed urethra.

    • Without proper closure, urine exits through the opening on the inferior side.

Epispadias

  • Definition: An opening of the urethra on the superior surface of the penis, which is rare.

  • Etymology: "Epi" means on top, referring to the location on the penis.

  • Cause: Abnormal positioning of the genital tubercle during development.

  • Associated Condition: Bladder exstrophy, where there is an opening of the anterior abdominal wall above the bladder, leading to incomplete formation and exposure of the bladder wall.

Condyloma

  • Definition: Benign epithelial tumors associated with HPV infections, similar to condylomata in the female genital tract.

  • Causes: HPV types 6 and 11 are responsible for development.

  • Characteristic Changes: Koilocytic changes, indicated by "raisin-like" nuclei in histological examination, which are diagnostic of HPV infection.

Lymphogranuloma Venereum

  • Definition: A sexually transmitted disease causing necrotizing granulomatous inflammation of the inguinal lymphatics.

  • Cause: Primarily caused by specific serotypes of Chlamydia trachomatis (L1 to L3).

  • Features:

    • Chlamydia is an obligate intracellular organism needing host ATP for survival; infects mucosal surfaces as elementary bodies, which convert to reticulate bodies within host cells.

    • Serotypes differentiation:

    • A-C: Trachoma

    • D-K: Urogenital infections and conjunctivitis

    • L1-L3: Lymphogranuloma venereum

  • Complications: Potential for healing with fibrosis but may also lead to rectal strictures, particularly with perianal involvement.

Squamous Cell Carcinoma of the Penis

  • Definition: Malignant proliferation of squamous cells in penile skin.

  • Risk Factors:

    • High-risk HPV types (16, 18, 31, 33) account for two-thirds of cases.

    • Lack of circumcision as improper maintenance of the foreskin increases inflammation risk.

  • Precursor Lesions:

    1. Bowen's Disease:

    • Presentation: In situ carcinoma manifesting as leukoplakia (white plaque) on the shaft of the penis.

    • Diagnosis: Biopsy reveals malignant cells not invading the basement membrane.

    1. Erythroplasia of Keuart:

    • Presentation: In situ carcinoma appearing as erythroplakia (red plaque) on the glands of the penis.

    1. Bowenoid Papulosis:

    • Presentation: Reddish papules on the skin of the penis, representing in situ carcinoma that typically does not progress to invasion.