Vaginal DHEA to Improve Vaginal Health After Radiation for Women With Gynecologic, Anal or Rectal Cancer

Inclusion Criteria: * Any patient with anal, rectal, cervical, vaginal, or vulvar cancer receiving external beam radiation alone, or both external beam radiation and brachytherapy with curative intent (Participants will be consented and enrolled prior to starting treatment but will not receive intervention till after treatment is completed) * Concurrent or prior chemotherapy is allowed * Any prior gynecologic surgery is permitted * Rectal surgery, including lower anterior resection and abdominoperineal resection, is permitted * Subject must be menopausal, which is defined as age \> 50 with no menses for 12 months or bilateral oophorectomy Exclusion Criteria: * Patients with scleroderma, mixed connective tissue disorder, and lupus will be excluded * Patients who have received prior pelvic radiation * Undiagnosed abnormal genital bleeding (unrelated to current diagnosis or treatment related toxicity) * Endometrial cancer or endometrial hyperplasia * Use of estrogen alone injectable or progestin implant therapy with 3 months before study entry * Use of estrogen pellet or progestin injectable drug within 6 months before study entry * Use of oral estrogen, progestin, or DHEA or intrauterine progestin within 8 weeks before study entry * Use of vaginal estrogen (rings, creams, tablets, or gels), transdermal estrogen +/- progestin, vaginal hyaluronic acid, or pro-estrogenic herbal treatments such as black cohosh in the 4 weeks before study entry. Intravaginal moisturizers and lubricants prior to enrollment are permitted * History of breast cancer * Patients receiving palliative radiation therapy * Patients who do not meet criteria for menopause