A localized swelling or enlargement in one area of the abdomen. An abdominal mass is usually detected on routine physical examination . It may not have been detected by the affected person because most abdominal masses develop slowly. The location of the mass, and its firmness, texture, and other qualities can provide clues as to the cause of an abdominal mass. 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.