B1CC was the most common fusion partner in the patients with cholangiocarcinoma from other countries, accounting for up to 29% of FGFR2 rearrangements26, 28, 31; this fusion partner seems to be less frequent in Chinese patients (6.7% in our study and none in another study30), but definite conclusions could not be reached because of the limited sample size. The gene discussed is FGFR2; the disease is cholangiocarcinoma.