Role of needle knife assisted ampullary biopsy in the diagnosis of periampullary carcinoma

Figure 1 Duodenoscopy showing a periampullary mass with stent in situ and needle knife coming out of endoscope (A) and endoscopic image after needle knife papillotomy showing exposed tumor tissue (B).

Figure 2 Computed tomography showing dilated common bile duct with stent in it (arrow) and dilated main pancreatic duct (arrowhead); no definite mass could be visualized.

Figure 3 Endoscopic ultrasound image of the same patient as in Figure 2, showing dilated common bile duct measuring 11. 8 mm with stent in situ (arrow); a mass is seen in the periampullary region measuring 1.2 cm × 1.8 cm (arrowheads).

Figure 4 Photomicrograph showing papillary adenocarcinoma; tumor cells are arranged in both papillary fronds and glands (HE, × 240).