Although mutations of ERBB4 have been identified in patients with CC (S79Y, R106C, D376Y, C580*, K682N, F682L, E835D, R847C, R938C, Y950H, D960G, R992H, Y1066H, P1092S, Q1126K, Q1270K), its function remains unknown [112]. This evidence concerns the gene ERBB4 and cholangiocarcinoma.