The most common cancer in young women is breast cancer. Women under 40 can develop breast cancer at any time, from teenage years to adulthood. Breast cancer is more common in young women who have a history of breast cancer. Other risk factors include a family background, an early menopause or menarche and high estrogen levels. The symptoms of breast cancer are difficult to detect in younger women due to the changes occurring during puberty. There are many symptoms that can be seen in young women, including a mass or lump in breast tissue which does not disappear after menstruation. Other signs include pain in one part of the body or dimpling in the skin. Physical examinations are followed by imaging tests, such as mammograms or ultrasounds. MRIs can also be used, along with biopsy if needed. Treatment depends on stage and severity of cancer. It may include chemotherapy (drugs that are taken intravenously or orally), radiation therapy, hormone therapies and surgery.