Though CA125 is valuable to look for recurrence of cancer, it is not recommended for screening because it can surge, for example, during menstruation. However, guidelines from the American College of Obstetricians and Gynecologists and the National Comprehensive Cancer Network (NCCN) recommend a CA125 test plus vaginal ultrasound imaging for a woman with nonspecific symptoms that could signal ovarian cancer, such as bloating and pain. A CT or MRI scan may be added, although these are expensive. A biopsy is usually avoided because it could spread cancer cells.