Figure 1From: Primary small-cell neuroendocrine carcinoma of the duodenum – a case report and review of literature(a) Duodenoscopy showing a 3 × 3 cm protruding tumor with two ulcerations located opposite the ampulla of Vater in the second portion of the duodenum. (b) Hypotonic duodenography showing the donuts-shape tumor in the duodenum.Back to article page