Figure 1.

Four patterns of pancreatic cancer with distinctive morphological features of the cancer-cell and stromal compartments. (a) The periglandular pattern (PP) is characterized by medium-sized simple glands surrounded by a moderate amount of stroma that encircles the tumor glands. (b) In the tendon-like pattern (TP), the large cystic-papillary tumor glands are embedded in a vast and dense fibrous stroma. (c) The fascicular pattern (FP) typically contains medium-sized tumor glands that are often angulated and lie in a highly cellular, whorled stroma. (d) In the chickenwire pattern (CP), tumor glands are small and lie densely packed with little intervening stroma.