Refining the 8th edition TNM classification for EBV related nasopharyngeal carcinoma
Xiaojing Du, Gaoyuan Wang, Xiao‐Dong Zhu, Yaqian Han, Lei Feng, Liangfang Shen, Kunyu Yang, Lei Chen, Yan‐Ping Mao, Ling‐Long Tang, Ling Li, Zheng Wu, Guiqiong Xu, Qin Zhou, Jing Huang, Rui Guo, Yuan Zhang, Xu Liu, Guan‐Qun Zhou, Wen‐Fei Li, Cheng Xu, Lin Li, Yu‐Pei Chen, Fo‐Ping Chen, Xiaoyu Liang, Siyuan Chen, Shuqi Li, Chunyan Cui, Jibin Li, Jian Ren, Ming‐Yuan Chen, Lizhi Liu, Ying Sun, Jun Ma
Abstract
The AJCC/UICC TNM classification describes anatomic extent of tumor progression and guides treatment decisions. Our comprehensive analysis of 8,834 newly diagnosed patients with non-metastatic Epstein-Barr virus related nasopharyngeal carcinoma (NPC) from six Chinese centers indicates certain limitations in the current staging system. The 8th edition of the AJCC/UICC TNM classification inadequately differentiates patient outcomes, particularly between T2 and T3 categories and within the N classification. We propose reclassifying cases of T3 NPC with early skull-base invasion as T2, and elevating N1-N2 cases with grade 3 image-identified extranodal extension (ENE) to N3. Additionally, we suggest combining T2N0 with T1N0 into a single stage IA. For de novo metastatic (M1) NPC, we propose subdivisions of M1a, defined by 1-3 metastatic lesions without liver involvement, and M1b, characterized by >3 metastatic lesions or liver involvement. This proposal better reflects responses of NPC patients to the up-to-date treatments and their evolving risk profiles.