Abstract：Objective To evaluate the 7th edition of the International Union against Cancer/American Joint Committee on Cancer (UICC/AJCC) staging system for nasopharyngeal carcinoma (NPC), and to provide a basis for its further revision. Methods Three hundred and twenty-three patients who were pathologically diagnosed with NPC (without distant metastasis) and received radical intensity-modulated radiotherapy (IMRT) in our hospital from 2005 to 2011 were enrolled as subjects. All patients were staged according to the 7th edition of the UICC/AJCC staging system. The overall survival (OS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) rates were calculated using the Kaplan-Meier method, and pairwise comparisons were made by the log-rank test. Multivariate prognostic analyses were performed using the Cox regression model. Results The 5-year sample size was 45. There were no significant differences in 5-year LRFS between stages T1 and T2, as well as between stages T2 and T3(P=0.055;P=0.746). The current stages T2, T3, and T4 with only medial pterygoid muscle were combined into stage T2, and the rest of stage T4 were down-staged to stage T3. In the new T staging system, the LRFS curves of stages T1, T2, and T3 were substantially separated. There were no significant differences in 5-year DMFS between stage N2 and N3a, between stage N2 and N3b, and between stages N3a and N3b (P=0.272;P=0.063;P=0.810). Multivariate analyses demonstrated that cervical lymph node metastasis was the only independent prognostic factor for DMFS (P=0.037). The current stage N3a with cervical lymph node metastasis on one side was down-staged to stage N1, and the current stage N3a with cervical lymph node metastasis on both sides to stage N2. In the new N staging system, the DMFS curves of stages N0, N1, N2, and N3 were substantially separated. There were no significant differences in 5-year OS between stages I and II, as well as between stages III and IVa (P=0.434;P=0.951). The current stages T1N0-1, T2N0-1, T1-3N2/T3N0-1, and T1-3N3 were classified into stage Ia, Ib, II, and III, respectively. In the new staging system, the 5-year OS curves of stages Ia, Ib, II, and III were substantially separated. Conclusions There are several deficiencies in the 7th edition of the UICC/AJCC staging system. The proposed new staging system can achieve a better prognosis, though further validations with a larger sample size are needed. DOI:10.3760/cma.j.issn.1004-4221.2015.03.014 作者单位:330029 南昌,江西省肿瘤医院放疗科 通信作者:李金高,Email:lijingao@hotmail.com
Zeng Lei,Gong Xiaochang,Ao Fan et al. Evaluation of staging system for nasopharyngeal carcinoma based on intensity-modulated radiotherapy[J]. Chinese Journal of Radiation Oncology, 2015, 24(3): 285-288.
[1] Cooper J, Fleming ID, Henson DE, et al. American joint committee on cancer manual for staging of cancer[M]. 6th ed. Philadelphia:JB Lippincott,2002:4-5. [2] Tang LL, Li WF, Chen L, et al. Prognostic value and staging categories of anatomic masticator space involvement in nasopharyngeal carcinoma:a study of 924 cases with MR imaging[J].Radiology,2010,257(1):151-157.DOI:10.1148/radiol.10100033. [3] Zhang GY, Huang Y, Cai XY, et al. Prognostic value of grading masticator space involvement in nasopharyngeal carcinoma according to MR imaging findings[J]. Radiology,2014,273(1):136-143.DOI:10.1148/radiol.14132745. [4] Chen L, Mao YP, Xie FY, et al. The seventh edition of the UICC/AJCC staging system for nasopharyngeal carcinoma is prognostically useful for patients treated with intensity-modulated radiotherapy from an endemic are in China[J]. Radiother Oncol,2012,104(3):331-337.DOI:10.1016/j.radonc.2011.10.009. [5] Lee AW, Ng WT, Chan LK, et al. The strength/weakness of the AJCC/UICC staging system (7th edition) for nasopharyngeal cancer and suggestions for future improvement[J]. Oral Oncol,2012,48(10):1007-1013.DOI:10.1016/j.oraloncology.2012.03.022. [6] Lee AW, Foo W, Poon YF, et al. Staging of nasopharyngeal carcinoma:evaluation of N-staging by Ho and UICC/AJCC systems[J]. Clin Oncol,1996,8(3):146-154. [7] Mao YP, Liang SB, Liu LZ, et al. The N staging system in nasopharyngeal carcinoma with Radiation Therapy Oncology Group guidelines for lymph node levels based on magnetic resonance imaging[J]. Clin Cancer Res,2008,14(22):7497-7503.DOI:10.1158/1078-0432.CCR-08-0271. [8] Li WF, Sun Y, Mao YP, et al. Proposed lymph node staging system using the international consensus guidelines for lymph node levels is predictive for nasopharyngeal carcinoma patients from endemic areas treated with intensity modulated radiation therapy[J]. Int J Radiat Oncol Biol Phys,2013,86(2):249-256.DOI:10.1016/j.ijrobp.2012.09.003.
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