The Prognostic Value of Albumin-to-Alkaline Phosphatase Ratio before Radical Radiotherapy in Patients with Non-metastatic Nasopharyngeal Carcinoma: A Propensity Score Matching Analysis

Purpose We first analyzed the prognostic power of albumin-to-alkaline phosphatase ratio (AAPR) before radical radiotherapy (RT) in non-metastatic nasopharyngeal carcinoma (NPC) patients. Materials and Methods The records of 170 patients with biopsy-proven, non-metastatic NPC treated by radical RT between 1998 and 2016 at our institution were retrospectively reviewed. Median follow-up duration was 50.6 months. All patients received intensity-modulated RT and cisplatin based chemotherapy before, during, or after RT. The major treatment of patients was based on concurrent chemoradiotherapy (92.4%). The AAPR was calculated by the last value of both albumin and alkaline phosphatase within 1 month immediately preceding RT. The optimal cut-off level of AAPR was determined by using Cutoff Finder, a web-based system. Propensity score matching (PSM) analysis was performed. Results The optimal cut-off level of AAPR was 0.4876. After PSM analysis of whole cohort, an AAPR was not related to survival outcomes. In PSM analysis for patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC), an AAPR >= 0.4876 was related to better overall survival (OS), progression-free survival (PFS), and locoregional relapse-free survival (LRRFS) (OS: hazard ratio [HR], 0.341; 95% confidence interval [CI], 0.144 to 0.805; p=0.014; PFS: HR, 0.416; 95% CI, 0.189 to 0.914; p=0.029; and LRRFS: HR, 0.243; 95% CI, 0.077 to 0.769; p=0.016, respectively). Conclusion The AAPR, inexpensive and readily derived from a routine blood test, could be an independent prognostic factor for patients with LA-NPC. And it might help physicians determine treatment plans by identifying the patient's current status. Future prospective clinical trials to validate its prognostic value are needed.