You are in Medical Library . Definition A localized swelling or enlargement in one area of the abdomen. Common Causes Abdominal aortic aneurysm can cause a pulsating mass around the navel or right-upper quadrant.
Cholelithiasis can cause a painless, smooth mass in the right-upper quadrant.
Diverticulitis can cause a mass that is usually located in the left-lower quadrant. Gallbladder tumor can cause a moderately tender, irregularly shaped right-upper quadrant mass. Kidney cancer can sometimes cause a mass in the abdomen. Neuroblastoma , a malignant tumor often found in the lower abdomen, that primarily occurs in children and infants. Ovarian cyst can cause a smooth, rounded, rubbery mass above the pelvis in the lower abdomen.