CDKN2A and lung cancer: Although circulating anti‐p16 antibodies have been found to be increased in several types of solid tumors, such as nasopharyngeal cancer 9, hepatocellular carcinoma 9, breast cancer 10, esophageal cancer 11, cervical cancer 12 and non‐small cell lung cancer (NSCLC) 13, the reports to date on altered anti‐p16 antibody levels in early stage cancer remain inconsistent.