Ulcers often occur within the duodenum, usually in the first part just beyond the stomach which is called the duodenal cap. Ulcers can come in all shapes and sizes. Image 1 shows a single white-based ulcer. Image 2 shows numerous small ulcers scattered across the duodenal cap. Image 3 demonstrates a huge duodenal ulcer almost filling the cap. Note the brownish areas across the whitish base which is caused by some old blood. Some fresh bleeding is seen at the edge. Duodenal ulcers are caused by the bacteria, Helicobacter pylori, or by arthritis medications such as Advil, Motrin, Naprosyn, aspirin and many others. All of these ulcers healed under appropriate therapy.