Dou S, Li R, Zhang L, et al. - Researchers undertook this prospective analysis to assess if and how elective mucosal irradiation (EMI) could exert long-term benefit in Chinese head and neck cancer of unknown primary (HNCUP) patients. They carried out a phase II, single-arm trial at two centers in China. The EMI approach was particularly customized to Chinese patients by distinguishing HNCUP as putative nasopharyngeal carcinoma (NPC) or non-putative NPC. The main outcome of interest was 3-year mucosal recurrence-free survival (MRFS). Of 48 patients enrolled, 46 were examined, including 24 putative NPC and 22 non-putative NPC patients. The 3-year MRFS was estimated to be 90.6%. The 5-year MRFS, regional-recurrence free survival and overall survival (OS) were estimated to be 90.6%, 86.0%, and 90.6%, respectively. In this first prospective inquiry into the long-term results of EMI in Chinese HNCUP patients, findings revealed excellent MRFS and OS rates.