Ultrasound

Ultrasound uses sound waves to create an image of your breast on a computer screen. By analyzing this image, your doctor may be able to tell whether a lump is a cyst or a solid mass. Cysts, which are sacs of fluid, usually aren't cancerous, although your doctor may recommend draining the cyst. If the cyst appears very typical and disappears completely with removal of the fluid, then observation is the only follow-up necessary. If the cyst appears complex, doesn't disappear completely when the fluid is drained or contains bloody fluid, a biopsy is necessary to determine whether cancer is present.