Colon cancer can often be effectively treated when found early. In fact, it can often be prevented entirely when precancerous polyps are detected and removed through routine screening via colonoscopy. Nonetheless, the disease is among the leading causes of cancer death overall among men and women in the United States, according to the American Cancer Society. It's much more difficult to treat when it has spread beyond the colon. When colon cancer metastasizes--or spreads--it most often goes to the liver or lungs. But it can also reach other areas, such as the brain and bones.
Liver
When colon cancer metastasizes to the liver, symptoms commonly include fever, weight loss, nausea and lack of appetite. Other typical signs of such spread are a yellowish color to the skin, pain or even fluid in the abdomen, and swollen legs. Computed tomography (CT) scans, abdominal ultrasound and blood tests to evaluate liver function can be used in determining whether colon cancer has spread to the liver.
Lungs
Symptoms of colon cancer metastasis to the lung can include being short of breath, having a nonproductive cough, having a cough with blood-containing sputum and experiencing pain in the chest. Chest X-ray and CT scan are the tests commonly used to check for spread of cancer to the lungs.
Brain
Metastatic cancers found in the brain are more likely to have come from the lung or breast than from the colon. Nonetheless, colon cancer sometimes reaches the brain, accounting for about 5 percent of metastatic cancers found there. Among the more common symptoms in such cases are blurry vision, headaches and dizziness. CT scan and magnetic resonance imaging (MRI) can be used to check.
Bone
Spread of colon cancer to the bone is not particularly common, but it does happen-- especially when the cancer has metastasized widely throughout the body. When this occurs, patients are likely to experience pain in the affected areas and, often, broken bones following very minor injuries or even with no injury at all. Testing for bone metastasis includes X-ray and bone scanning, in which a medical provider gives an intravenous injection of a contrast chemical and examines the entire body using a special camera.
