SALL4 and intrahepatic cholangiocarcinoma: Contradictory to his own hypothesis, Tanaka et al. [18] (accounting for 13% of heterogeneity) attributed the opposite outcome in SALL4 positive group to the unbalanced patient distribution (SALL4-negative group consists of more intrahepatic cholangiocarcinoma patients who feature a lower SALL4 staining percentage but a poorer prognosis).