Review Question - QID 210927

A 29-year-old woman presents to her gynecologist because of chronic pelvic pain that she has been experiencing for the last 6 months. Specifically, she says that she has severe pain during menstruation that is localized primarily to her lower abdomen and pelvis. In addition, she has been having pain while defecating and during intercourse. She has no past surgical history and her past medical history is significant for asthma. She uses protection while having intercourse with her long time boyfriend and has never been pregnant. Physical exam reveals adnexal tenderness and the presence of an adnexal mass. Laparoscopic examination is conducted showing several cysts filled with dark brown fluid on her ovaries and powder burn marks along her peritoneal surfaces. Which of the following markers would most likely be elevated in this patient?