IHC analysis of LKB1 protein showed that LKB1 was significantly under-expressed in a high percentage of ICC tissues compared with the matched peritumor bile duct tissues (mean LKB1 density 0.326 ± 0.021 vs. 0.369 ± 0.027, respectively, P < 0.05) as shown in Figure 2B. The gene discussed is STK11; the disease is intrahepatic cholangiocarcinoma.