Ovarian cancer is deadly if not detected early, but it is only one of many causes of pelvic masses, which are common. The physician's job is to determine if a mass is likely to be malignant and needing surgical evaluation. The best predictors of malignancy are a combination of factors that include the patient's age, family history, menopausal status, symptoms, findings on physical examination and imaging studies, and blood level of the cancer biomarker CA125.