Cancer of the Vagina
Primary carcinoma of the vagina is rare and comprises only 1-2% of all female genital malignancies. To be classified as primary vaginal cancer, the lesion must arise in the vagina and must not involve the cervix or vulva. More than 80% of primary vaginal cancers are squamous cell carcinomas, and these squamous cell lesions usually occur in postmenopausal women. The nonsquamous cancers tend to occur in younger females. For example, embryonal rhabdomyosarcomas and endodermal sinus tumors usually occur in children younger than 5 years of age, whereas the rare clear-cell adenocarcinoma, epidemiologically related to diethylstilbestrol (DES), is declining in incidence.
Epidemiologic factors associated with the occurrence of preinvasive and invasive squamous cell lesions include chemotherapy, chronic vaginal irritation, excessive douching, a history of condyloma acuminatum, immunosuppressive treatment or states, long-term pessary use, low socioeconomic status, neglected prolapse, previous irradiation for cervical cancer, primary hysterectomy for cervical intraepithelial neoplasia (CIN) or for benign disease, and multiple sex partners. No single predisposing factor or a combination of factors have been identified.
Vaginal Intraepithelial Neoplasia
Vaginal intraepithelial neoplasia accounts for fewer than 1% of lower genital intraepithelial lesions. Women with vaginal intraepithelial neoplasia tend to be one to two decades younger than those with invasive squamous lesions. Vaginal intraepithelial neoplasia is most often associated with prior or coexistent neoplasia of the cervix or vulva. Prior pelvic irradiation, immunosuppression, or a history of HPV are other common predisposing factors.