Lower abdominal pain

A 63-year-old woman presented to our emergency room with lower abdominal pain. She described the pain as dull, involving the right lower quadrant, non-radiating and constant. She also reported multiple episodes of non-bloody and non-bilious vomiting. However, her prior medical problems included osteoarthritis requiring right-sided total knee replacement five years before this episode. She took ibuprofen 400 mg for knee pain on a needed basis for the past eight years. She had no family H/o inflammatory bowel disease, colon cancer, or GI-related disorder. She denied smoking, using alcohol, and she reported no illicit drug use. 

Her physical examination, including the abdominal examination, was unremarkable. Her laboratory examinations did not reveal any leuko-cytosis, but CRP was elevated to 55 mg/L. The contrast CT scan of the abdomen revealed focal mucosal thickening in the cecum, which was highly suspicious for colonic malignancy. She had a colonoscopy which showed two masses and ulcers in the right colon; pathology was negative for malignancy but showed consistent inflammation.