How do you treat ovarian cancer? The first step after being diagnosed with chemotherapy is typically surgery. The purpose is to remove all visible signs of cancer. As a part of the surgery, doctors might have to remove parts of the intestine, the colon, the spleen, the ovaries, and the diaphragm. Following this surgery, patients with ovarian cancer receive chemotherapy for six to eighteen months. The duration varies between patients depending on risk factors and which type of cancer they have. If a patient with ovarian cancer is not a candidate for surgery upon diagnosis because in very poor health, they may start with chemotherapy to relieve the symptoms a little and then surgery.