Figure 2.

(A) An area-proportional Venn diagram demonstrates the distribution of KRAS, GNAS, BRAF, NRAS, and HRAS mutations identified through prospective PancreaSeq testing of 1887 pancreatic cysts. In addition to KRAS and GNAS, BRAF alterations were often identified in EUS-FNA obtained pancreatic cyst fluid specimens and frequently co-occurred with GNAS mutations. (B) Most BRAF alterations found in pancreatic cysts were non-V600E mutations and were predominantly categorized as class II and class III BRAF mutations (n = 83, 91 %). (C) Based on correlative imaging and pathologic studies, BRAF-mutant pancreatic cysts (white arrowhead) were commonly found to communicate with the main pancreatic duct, and (D) on gross pathology, exhibited abundant, thick mucin (white arrowheads). (E and F) Microscopically, BRAF-mutant cysts corresponded to an intraductal papillary mucinous neoplasm with prominent papillary fronds and often lined by both gastric and intestinal epithelium. (E) Hematoxylin and eosin stain, magnification 40×. (F) Hematoxylin and eosin stain, magnification 200×.