The different impact of 7th ed AJCC cancer staging system on nasopharyngeal carcinoma treated with conventional radiotherapy and intensity-modulated radiotherapy / 中华放射肿瘤学杂志

ABSTRACT

Objective To compare the prognostic value of the 7th edition of AJCC cancer staging system in nasopharyngeal carcinoma (NPC) patients treated with conventional radiotherapy (CRT) and intensity-modulated radiotherapy (IMRT).Methods From January 2004 to December 2006,totally 1138 NPC patients were treated with CRT (790 patients) and IMRT (348 patients) in Cancer Hospital of Fujian province.The median ages were 47 and 45 years old for two groups ( x2 =1.49,P =0.222 ),respectively.There were 0,41,488,261 and 5,65,176,102 patients in stage Ⅰ,Ⅱ,Ⅲ,Ⅳ of the two groups after restaged with 7th edition of AJCC cancer staging system,respectively (x2 =64.78,P =0.001 ).The 3-year survival was analyzed according to T-category,N-category and overall stage.Results The follow-up rate at 3 years is 96.0％.The median follow-up were 32 months and 33 months for CRT and IMRT groups.N-category was found to be the prognostic factors for overall survival (OS,x2 =6.50,P =0.038 and x2 =13.60,P =0.004) and metastasis free survival ( MFS,x2 =7.78,P =0.009 and x2 =15.30,P =0.002) for CRT and IMRT groups.The clinical stage was prognostic factor for OS in conventional group ( x2 =6.70,P=0.035),and for MFS in IMRT group (x2 =9.12,P=0.028).Conclusions The T-calegory of 7th AJCC staging system shows poor predictive value for the long-term survival of NPC patients.The N-calegory of 7th AJCC staging system can well estimate the OS and MFS for NPC.