The value of circulating CYFRA21-1 expression in patients with nasopharyngeal carcinoma: a study of 529 subjects

Background Early diagnosis of nasopharyngeal carcinoma (NPC) needs more reliable biomarkers. The aim of this study was to investigate serum cytokeratin 19 fragment 21.1 (CYFRA21-1) as an NPC biomarker based on data from a large sample.