A complex cyst has both fluid-filled and solid parts. While a simple cyst only has fluid inside it and is usually not cancerous, a complex cyst can be cancerous. After diagnosticians find a complex mass, they take a sample to find out whether it contains cancer, reports eMedicineHealth.
When a physician becomes aware of a mass in the body, as on a kidney or ovary, he may order an ultrasound test to determine the type of mass. Ultrasound testing can differentiate between a solid mass and one that is filled with fluid, and it can also identify complex cysts. In some cases, Doppler technology can identify patterns common to tumors to make the screenings more helpful, as stated by eMedicineHealth.
A CT scan is a form of X-ray that provides additional detail of the affected area in three dimensions, which provides considerably more data about the tumor's reach and size. It also shows any metastasis to other organs in the area. Some cancers release tumor markers into the blood, which the doctor can identify with blood testing. For example, when testing for ovarian cancers, doctors look for the CA-125 marker, according to eMedicineHealth, as it shows up in about 80 percent of advanced cases and about half of early cases.