An example of one of the striking changes is reflected in the reclassification of a p16-positive OPSCC cancer (2 cm tumor with two positive ipsilateral lymph nodes, T1N2M0) from stage IV in the previous AJCC manual to stage I. Although some challenges exist, including the potential difficulty of identifying the primary tumor site in advanced-stage OPSCC and a lack of case-controlled studies, better prediction of HPV-OPSCC prognosis is expected using both the clinical and the pathologic data sets (Wang et al., 2015). The gene discussed is CDKN2A; the disease is cancer.