PTGS2 and hepatocellular carcinoma: A case–control study of Chinese samples suggested that PTGS2 −765G/C and −1195A/G increase the genetic susceptibility to HCC, with −765GC and −1195AA associated with 2.89 and 1.57 times higher risk, respectively.15 Conversely, a decreased risk was detected for −765G/C and no association was found for −1195A/G and +8473T/C in Turkish samples.16 The controversial results are probably caused by sampling variance and population heterogeneity.