International Ovarian Tumour Analysis (IOTA) Phase 5

The purpose of this study is to learn more about the appearance and behavior of benign-looking adnexal masses. * Benign-looking means that when viewed here by ultrasound it has the appearance of looking not harmful or not malignant. * Adnexal refers to the 'adnexa', the space in the female pelvis on either side of the uterus (or where the uterus used to be if you previously had a hysterectomy). The adnexa includes, but is not limited to, the ovaries and the fallopian tubes. * Masses refers to a variety of structures, including but not limited to: * ovarian cysts that are fluid filled sacs within or attached to an ovary * ovarian tumors that can be solid tissue or a combination of cysts and solid tissue * hydrosalpinges that are fluid collections in the fallopian tube Many women have what appear to be benign adnexal masses. Many times, removal of the masses with surgery is not necessary. Often surgery is performed unnecessarily, for fear that these masses could be cancer. There is not much information available for doctors to know how and when to follow these masses, or which ones will become cancer. This study will combine information from centers all around the world regarding the behavior of all types of benign adnexal masses. The aim of this study is to develop decision tools for doctors to know the best way to treat these masses in order to improve the detection of ovarian cancer while at the same time reduce the number of unnecessary operations.