Since the original report of PCDH10 promoter methylation in breast cancer [13], this phenomenon has been detected in medulloblastomas, nasopharyngeal and esophageal carcinomas, gastric cancer, colorectal cancer, hepatocellular carcinoma, pancreatic cancer, breast cancer, cervical cancer, testicular cancer, prostate cancer, bladder cancer, non-small cell lung cancer and multiple haematologic malignancies [8–10]. The gene discussed is PCDH10; the disease is hepatocellular carcinoma.