Figure 5.

Four patterns of pancreatic cancer with distinctive morphological, structural and functional features of the cancer-cell and stromal compartments. (a) In the periglandular pattern, the stromal sheath that encircles the tumor glands contains a moderate amount of CAFs and is rich in fibronectin and MMP14, produced by both CAFs and PCCs. The latter show moderate expression of ALDH1 and Ki67. (b) The tendon-like pattern has a collagen- and hyaluronan-rich stroma that is devoid of fibronectin and shows marked fiber alignment. The majority of cancer cells express ALDH1. Note the low levels of MMP14 and Ki67. (c) The whorled stroma of the fascicular pattern contains a high number of CAFs with high expression of ITGα5 and marked deposition of aligned fibronectin. Note the high-level expression of MMP14 in stroma and PCCs. (d) The small stromal compartment in the chickenwire pattern is relatively rich in hyaluronan but contains little collagen and fibronectin and lacks fiber alignment. CAFs are low in number. Note the high Ki67-expression in the PCCs. ALDH1, aldehyde dehydrogenase 1; CAF, cancer-associated fibroblast; ITGα5, integrin α5; MMP14 matrix metalloproteinase 14; PCC, pancreatic cancer cell.