Precursors to pancreatic cancer

Abstract

Infiltrating ductal adenocarcinoma of the pancreas is believed to arise from morphologically distinct noninvasive precursor lesions. These precursors include the intraductal papillary mucinous neoplasm, the mucinous cystic neoplasm, and pancreatic intraepithelial neoplasia. Intraductal papillary mucinous neoplasms are grossly visible mucin-producing epithelial neoplasms that arise in the main pancreatic duct or one of its branches. The cysts of mucinous cystic neoplasms do not communicate with the major pancreatic ducts, and these neoplasms are characterized by a distinct ovarian-type stroma. Pancreatic intraepithelial neoplasia is a microscopic lesion. This article focuses on the clinical significance of these three important precursor lesions, with emphasis on their clinical manifestations, detection, and treatment.

Figure 1

Mucinous cystic neoplasm. Note the large size of the cysts and the presence of glistening mucin.

Figure 2

Photomicrograph of a mucinous cystic neoplasm. The neoplastic mucin-producing columnar epithelial cells rest on a layer of cellular “ovarian-type” stroma.

Figure 3

Intraductal papillary mucinous neoplasm involving the main pancreatic duct. The duct is dramatically distended by neoplastic papillae.

Figure 4

Photomicrograph of an intraductal papillary mucinous neoplasm. The neoplastic mucin-producing columnar epithelial cells form long finger-like papillae. Abundant intraluminal mucin is present.

Figure 5

Photomicrograph of a colloid carcinoma of the pancreas. The neoplastic cells are embedded in copious quantities of extra-cellular mucin.

Figure 6

Normal pancreatic duct (A), PanIN-1B (B), PanIN-2 (C), and PanIN-3 (D). PanIN lesions are significantly smaller in size compared to the IPMN illustrated in Figure 4, and the papillae are shorter in length.

Figure 6

Normal pancreatic duct (A), PanIN-1B (B), PanIN-2 (C), and PanIN-3 (D). PanIN lesions are significantly smaller in size compared to the IPMN illustrated in Figure 4, and the papillae are shorter in length.

Figure 6

Normal pancreatic duct (A), PanIN-1B (B), PanIN-2 (C), and PanIN-3 (D). PanIN lesions are significantly smaller in size compared to the IPMN illustrated in Figure 4, and the papillae are shorter in length.

Figure 6

Normal pancreatic duct (A), PanIN-1B (B), PanIN-2 (C), and PanIN-3 (D). PanIN lesions are significantly smaller in size compared to the IPMN illustrated in Figure 4, and the papillae are shorter in length.