CD4 and pancreatic intraductal papillary-mucinous neoplasm: When we analyzed the engagement of CD4+ and CD8+ T cells in cystic lesions, we found that the percentage of CD4+ and CD8+ T cells in close proximity was high in IPMN (p < 0.0001, comparison: NNPT) but low in IAPA (p = 0.0383, comparison: IPMN) (Figure 4A).