Stromal CD3+ (P = 0.002), CD4+ (P = 0.007) and CD8+ (P < 0.001) T cells, CD20+ B cells (P = 0.008), MUM1+ plasma cells (P = 0.012) and CD163+ M2-like macrophages (P = 0.008) significantly decreased in IPN compared to non-tumorous biliary epithelium. The gene discussed is CD8A; the disease is bile duct papillary neoplasm.