Endometrioid carcinoma is a type of cancer that originates in the lining of the uterus, known as the endometrium. It is the most common form of endometrial cancer and typically occurs in women during their reproductive years or after menopause. This cancer is often linked to hormonal imbalances, particularly increased levels of estrogen. Symptoms of endometrioid carcinoma may include abnormal vaginal bleeding, pelvic pain, and changes in menstrual cycles. Diagnosis usually involves imaging tests and a biopsy of the uterine tissue. Treatment options often include surgery, radiation therapy, and hormone therapy, depending on the stage and severity of the disease.