PMP22 and bile duct papillary neoplasm: By screening the 36 genes known to be involved in both IPN and HL, pathogenic variants were identified in 16 patients out of 27 (59.26%): PMP22 (n = 5), SH3TC2 (n = 4), MPZ (n = 2), NEFL (n = 2), PRPS1 (n = 1), TRPV4 (n = 1), ABHD12 (n = 1) (Figure 1).