RESUMO
ObjectiveTo explore the effect of radiation dose on survival for stage Ⅳ non-small cell lung cancer (NSCLC) treated with concurrent chemotherapy and thoracic three-dimensional radiotherapy (CCTTRT).Methods From Jan.2003 to Jul.2010,201 Stage Ⅳ NSCLC patients were enrolled.Nineteen patients who received only one cycle chemotherapy were not included in survival analysis.Of the 182 patients eligible for survival analysis,all patients received platinum-based chemotherapy of two drugs.The median number of cycles was 4.The median dose to planning target volume of primary tumor ( DTPTV )was 63 Gy. Survival was calculated by Kaplan-Meier method and compared using the Logrank. Cox regression models were used to examine the effect of DTPTV on overall survival.ResultsThe follow-up rate of 201 patients was 97.5％.with 201,170 and 134 patients finished ＜ 1,1 -2 and ≥3 years' follow-up.The 1-,2-,3-year overall survival rate and median survival time was 20％,14％,0％ and 7.1 months;27％,10％,3％ and 9.6 months;and 59％,22％,16％ and 14.9 months,respectively for patients treated with DTPTV ＜ 45.0 Gy,45.0 - 62.1 Gy and ≥63.0 Gy,respectively ( χ2 =27.88,P =0.000 ) ;43％,19％,0％and 1 1 months and 2 0 ％,1 1％,5 ％ and 8 months,respectively for those received 2 - 3 cycles of chemotherapy and radiation dose ≥63 Gy and ＜ 63 Gy,respectively (χ2 =2.99,P =0.084) ;66％,23％,19％ and 16 months and 29％,12％,0％ and 8.8 months,respectively for those received 4 - 5 cycles chemotherapy and radiation dose ≥ 63 Gy and ＜ 63 Gy,respectively (χ2=15.87,P=0.000).No significant difference was found for patients received 2 - 3 cycles chemotherapy concurrently with DTP,Tv ≥63 Gy and 4 -5 cycles chemotherapy concurrently with DTPTV ＜63 Gy,respectively (χ2 =1.93,P =0.165).Multivariate analysis showed that 4 -5 cycles chemotherapy concurrently with DTPTv ≥63 Gy ( β =0.243,P =0.019),and improved KPS after treatment ( β =1.268,P =0.000) were independent favorable factors for survival.ConclusionChemotherapy concurrent with CCTTRT can prolong survival time of patients with stage Ⅳ NSCLC,especially for those treated with DTPTV ≥63 Gy.