Construction and validation of a biochemical signature to predict the prognosis and the benefit of induction chemotherapy in patients with nasopharyngeal carcinoma

This study aimed to develop and validate a biochemical signature for predicting the prognosis of patients with nasopharyngeal carcinoma (NPC) and explore roles of the constructed signature for screening optimal candidates for induction chemotherapy (IC). The biochemical signature was constructed based on a retrospective cohort of 3742 patients from January 2008 to December 2010; 2078 patients from prospective studies from January 2011 to December 2012 and 2153 patients from January 2013 to December 2016 served as validation cohort A and validation cohort B. Overall survival (OS) was the primary endpoint. The least absolute shrinkage and selection operator coefficients on the Cox regression model were calculated to construct the prediction model with the data of 33 biochemical indicators. A total of six prognostic indicators, including sodium, alkaline phosphatase, lactate dehydrogenase, albumin, indirect bilirubin, and cystatin-C, were screened for constructing the biochemical signature. The patients were divided into low-risk and high-risk groups using an optimal cut-off value of 0.823. The patients in high-risk group had significantly lower OS and distant metastasis-free survival (DMFS) compared with patients in low-risk group in three cohorts (P < 0.05). Furthermore, among patients with high-risk scores in the combined cohort, the addition of IC to CCRT further improved their OS and DMFS, whereas patients with low-risk scores did not benefit from IC. Our study developed and validated a clinically useful biochemical signature that could predict the survival outcomes in NPC patients. This signature can help clinicians design personalized treatment strategies.