Littoral cell angioma of the spleen is a rare defect characterized by abnormal cell growth in the spleen. The abnormal cell growth arises from the littoral cells which line the blood vessels within the spleen. Unlike other forms, this type of abnormal cell growth is usually harmless, and does not affect spleen function. However, in cases where it is harmful, it can cause individuals to experience fatigue, weight loss, excessive sweating, and abdominal pain. Individuals with this disease may however show no outward symptoms. Treatment depends on the severity of the defect. If the defect becomes harmful, doctors may suggest individuals undergo surgery to remove the abnormal cell growth from the spleen.