Prognostic factors and failure patterns in non-metastatic nasopharyngeal carcinoma after intensity-modulated radiotherapy
10.1186/s40880-016-0167-2
- Author:
Mao YANPING
1
;
Tang LINGLONG
;
Chen LEI
;
Sun YING
;
Qi ZHENYU
;
Zhou GUANQUN
;
Liu LIZHI
;
Li LI
;
Lin AIHUA
;
Ma JUN
Author Information
1. State Key Laboratory of Oncology in South China
- Keywords:
Nasopharyngeal carcinoma;
Intensity-modulated radiotherapy;
Prognosis;
Failure pattern;
Tumor staging
- From:Chinese Journal of Cancer
2016;35(12):673-682
- CountryChina
- Language:Chinese
-
Abstract:
Background:The prognostic values of staging parameters require continual re?assessment amid changes in diag?nostic and therapeutic methods. This study aimed to identify the prognostic factors and failure patterns of non?meta?static nasopharyngeal carcinoma (NPC) in the intensity?modulated radiotherapy (IMRT) era. Methods:We reviewed the data from 749 patients with newly diagnosed, biopsy?proven, non?metastatic NPC in our cancer center (South China, an NPC endemic area) between January 2003 and December 2007. All patients under?went magnetic resonance imaging (MRI) before receiving IMRT. The actuarial survival rates were estimated using the Kaplan–Meier method, and survival curves were compared using the log?rank test. Multivariate analyses with the Cox proportional hazards model were used to test for the independent prognostic factors by backward eliminating insigniifcant explanatory variables. Results:The 5?year occurrence rates of local failure, regional failure, locoregional failure, and distant failure were 5.4, 3.0, 7.4, and 17.4%, respectively. The 5?year survival rates were as follows: local relapse?free survival, 94.6%; nodal relapse?free survival, 97.0%; distant metastasis?free survival, 82.6%; disease?free survival, 75.1%; and overall survival, 82.0%. Multivariate Cox regression analysis revealed that orbit involvement was the only signiifcant prognostic fac?tor for local failure (P=0.011). Parapharyngeal tumor extension, retropharyngeal lymph node involvement, and the laterality, longest diameter, and Ho’s location of the cervical lymph nodes were signiifcant prognostic factors for both distant failure and disease failure (allP<0.05). Intracranial extension had signiifcant prognostic value for distant failure (P=0.040). Conclusions:The key failure pattern for NPC was distant metastasis in the IMRT era. With changes in diagnostic and therapeutic technologies as well as treatment modalities, the signiifcant prognostic parameters for local control have also been altered substantially.
