Introduction
NPC, tumour, colorectal cancers
NASOPHARYNGEAL CARCINOMA, DISEASE, TUMOUR, COLORECTAL CANCERS
Nasopharyngeal carcinoma (NPC) arises from the epithelium of the nasopharynx (Kamran et al. Maintenance therapy (MT) is a treatment strategy that continues drug treatment when the tumour burden reaches the minimum to delay progression and prolong OS; this approach has been successful in treating metastatic lung, breast, and colorectal cancers (Gerber and Schiller S1 is a third-generation fluorouracil derivative oral anticancer agent with excellent oral bioavailability and a similar effect to 5-FU continuous intravenous infusion (Chhetri et al. Biomarkers could be useful in predicting who might benefit from further treatments. Changes in the peripheral blood EBV-DNA load are related to changes in NPC burden, which might be more sensitive than imaging examinations in suggesting disease changes (Shen et al. The present prospective, multicentre, randomized controlled study was performed in metastatic NPC patients benefiting from the first-line chemotherapy to explore clinical value of S1 MT and the correlation between EBV-DNA, SAA status, and the benefits of MT. The results could help screen the patients who could achieve potential benefits from MT.