A 44-year-old multiparous woman presents with a chief concern of lower abdominal pain and lack of appetite for three months. The pain is not accompanied by fever or vaginal discharge. She describes the pain as a dull ache that comes on and off and is aggravated by physical activity and relieved by rest. Upon questioning, she states that the pain is non-cyclic and not triggered by the onset of menstruation. Her menstrual periods are regular, and her last Pap smear, carried out a year ago, did not reveal any abnormalities. Her last childbirth was 12-year ago. She had a copper intrauterine device (IUD) for contraception inserted six-year ago. She has noticed a 4-lb weight loss in the past six months. She denies nausea, vomiting, heartburn, diarrhea, constipation, or bloody stools.