As shown in Table 6, when using MVMR‐IVW to adjust fibronectin, Alloprevotella, Holdemania, LachnospiraceaeUCG010, Tyzzerella3, Rikenellaceae, Alistipes, Terrisporobacter and Dialister were no longer associated with periampullary cancer. Here, FN1 is linked to periampullary adenocarcinoma.