A bloated feeling in the right lower abdomen may be appendicitis or appendix cancer. Appendicitis is an inflammatory disease, mainly caused by bacterial infection of the appendix, or appendicitis may be caused by obstruction of the appendix lumen. Early manifestations are vague pain in the upper abdomen or around the umbilicus, accompanied by nausea, vomiting and other gastrointestinal symptoms. Slowly the pain moves to the lower right abdomen and is more severe in nature, but sometimes the pain in the lower right abdomen is not very severe in the early stages of appendicitis. Blood tests are needed to detect elevated white blood cells, and abdominal ultrasound or CT can detect swelling of the appendix and oozing around the appendix. In the case of appendix cancer, symptoms are atypical in the early stages and can present with vague pain and distension in the lower right abdomen. Sometimes abdominal CT can find a mass in the appendix, but sometimes it cannot, and colonoscopy is needed for further clarification.