Background: Given the distinct biological characteristics and regional distribution of nasopharyngeal carcinoma (NPC) compared with other head and neck cancers, and uncertainties regarding therapeutic strategies, physicians require high-quality clinical practice guidelines (CPGs) to provide transparent recommendations for NPC treatment. This study aimed to critically appraise the quality of NPC CPGs and assess the consistency of their recommendations. Methods: We identified CPGs that provided recommendations on the diagnosis and management of NPC published up to December 2015. Four investigators independently appraised CPG quality using the Appraisal of Guidelines for Research & Evaluation (AGREE) II instrument. Key recommendations by CPGs were also evaluated. Results: A total of 7 CPGs were eligible for this study: 5 produced by professional organizations or governmental agencies and 2 were developed based on expert consensus. Of the 6 AGREE II domains, the applicability domain scored consistently low across CPGs (range, 13.5%–30.2%); no CPG achieved a score of >50% in all 6 domains. The scope and purpose domain (≥73.6% for 4 CPGs) and editorial independence domain (≥75.0% for 6 CPGs) scored highest. Of the 23 AGREE II items, 9 scored less than half of the points available in all 7 CPGs. The recommendations by CPGs were consistent in general; heterogeneity mainly existed among recommended therapeutic strategies. Conclusions: Variation exists in NPC CPG development processes and recommendations. Increased efforts are required to make comprehensive resources available to guide healthcare providers and enhance delivery of high-quality, evidence-based care for NPC. International collaboration is necessary to enable the development of high-quality and regionally relevant CPGs for NPC.
Yu-Pei Chen, Ya-Qin Wang, Wen-Fei Li, Lei Chen, Cheng Xu, Tai-Xiang Lu, Ai-Hua Lin, Ji-Jin Yao, Yang-Chan Li, Ying Sun, Yan-Ping Mao and Jun Ma
Ling-Long Tang, Yu-Pei Chen, Yan-Ping Mao, Zi-Xian Wang, Rui Guo, Lei Chen, Li Tian, Ai-Hua Lin, Li Li, Ying Sun and Jun Ma
Background: In this study, we evaluated the 8th edition of the Union for International Cancer Control (UICC)/AJCC staging system for nasopharyngeal carcinoma (NPC) in an endemic area, with the aim of validating its applicability and providing further information for future refinements. Methods: A total of 1,790 patients with newly diagnosed, non–distant metastatic, histologically proven NPC treated with intensity-modulated radiotherapy (IMRT) were retrospectively reviewed. The performance of various staging systems was compared using the Akaike information criterion (AIC) and Harrell's concordance index (c-index). Results: For N (node) category, the survival curves of different groups according to the 8th edition were well-separated, and the prognostic model predicted outcomes fairly well. The 8th edition had higher AIC and c-index values for all end points than the 7th edition. However, probably due to the improved locoregional control provided by IMRT, the survival curves for T2 and T3 almost overlapped, without significant differences in locoregional failure-free survival (P=.606) and disease-free survival (P=.735). Due to the difficultly of differentiating T2 and T3, the AIC and c-index values were similar for the T categories of the 7th and 8th editions. Similarly, the overall survival and disease-free survival curves for stage II and III disease were not clearly separated for either the 8th or 7th editions. Conclusions: The 8th edition of the UICC/AJCC staging system for NPC enables more accurate prediction of treatment outcomes. However, several limitations need to be addressed in future editions, and it would be reasonable to further optimize the T category classification.