J Cancer 2017; 8(9):1665-1672. doi:10.7150/jca.19197 This issue
1. Department of Radiation Oncology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, P.R.China;
2. Department of Radiotherapy, cancer center of Guangzhou medical university, Guangzhou 510080, P.R.China;
3. Center of Gastrointestinal Surgery, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, P.R.China;
4. Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou 510060, P.R.China;
5. Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou 510060, Guangdong, P. R. China.
* These authors contributed equally to this work.
Purpose: To evaluate and improve the 7th edition International Union against Cancer/American Joint Committee on Cancer staging system for nasopharyngeal carcinoma.
Methods: A retrospective review of the data from 905 patients with biopsy-proven non-disseminated nasopharyngeal carcinoma was performed. All the patients were examined by magnetic resonance imaging (MRI) and received radiotherapy.
Results: Satisfied distributions among the stages were observed in the 7th edition staging systems. LRFS only differed in classifications betweenT1 and T3, T1 and T4 (P=0.022 and P=0.016, respectively). Significant differences were observed between patients without and with masticator space involvement for OS, DMFS and PFS (p<0.05). No statistically significant differences in LRFS were observed among different groups with anatomical masticator space involvement. The DMFS between N2 and N3b, N3a and N3b were lack of significance (P=0.060 and P=0.59). The T category and N category were independent prognostic factors for the major endpoints in the Cox multivariate regression analysis (P<0.01).
Conclusion: This study confirmed the prognostic value of the 7th edition UICC/AJCC staging system, the revisions of the 7th edition staging system are acceptable. However, our study also revealed limitations in the current staging system and suggested some potential modifications in future revision.
Keywords: Nasopharyngeal carcinoma, American Joint Committee on Cancer, Staging system, prognosis.