RESUMEN
Objective To analyze relation of comprehensive parameters of the dose-volume V5,V10 and V20 with radiation pneumonitis (RP) in patients with advanced stage non-small-cell lung cancer (NSCLC) treated with three-dimensional conformal (3DCRT) or intensity-modulated radiation therapy (IMRT).Methods Data of 90 patients with histologically proved NSCLC treated with 3DCRT or IMRT between November 2006 and July 2009 were collected.The median radiation dose of 70 Gy (range, 61 - 80 Gy) was delivered with late-course accelerated hyperfractionated radiotherapy (LAHRT).The V5 ,V10 ,V20,V30 and mean lung dose (MLD) were calculated from the dose-volume histogram system.The RP was evaluated according to the common toxicity criteria 3.0(CTC 3.0).Results The range of V5 ,V10 and V20 was 36% - 98%, 27% - 78% and 19% - 54%, respectively, with a median value of 66%, 48% and 31%, respectively.The RP of grade 1,2,3,4 and 5 was observed in 29,23,5,1 and 1 patients.The V5,V10 ,V20, contralateral V10, GTV,PTV, and numbers of fields were all significantly associated with RP of ≥grade 1 (χ2=2.04, 2.05, 2.01, 4.62, 6.50, 5.61, 5.61, and P= 0.044, 0.043, 0.047, 0.030,0.010,0.020,0.020).The V5, V10, V20, V30, and MLD were all significantly associated with RP of ≥ grade 2 (χ2= 2.05,2.20,2.96,4.96,5.20, and P = 0.040,0.030,0.000,0.030,0.020).In Logistic regression analysis, GTV was the only factor significantly associated with RP of ≥ grade 1 (χ2= 4.06, P =0.044).The V20 was the only factor significantly associated with RP of ≥grade 2(χ2=9.61,P=0.002).The RP of ≥grade 2 was significantly increased when V20 was more than 31%.The RP of ≥grade 2 was significantly increased when V20, V10 and V5 were more than 31%, 48% and 66%, respectively.The RP of ≥ grade 2 was significantly increased when V20 was more than 31% and V5 was more than 66%.Conclusions The comprehensive parameters combined with V5, V10 and V20 are effective in predicting RP.
RESUMEN
Objective To analyze the low dose-volume associated with radiation-induced lung injury (RILI) in patients with advanced non-small cell lung cancer (NSCLC) treated by three-dimensional confor-real radiation therapy (3DCRT). Methods Data of 100 patients with histologically proved NSCLC treated with 3DCRT or IMRT between November 2006 and January 2009 were collected. Nine patients treated with radiotherapy alone and 91 with radiotherapy combined with chemotherapy. A median dose of 70 Gy (range,60-80 Gy) was delivered with late-course accelerated hyperfractionated radiotherapy (LAHRT). Twenty-four patients received dose of 61-69 Gy and 76 received more than 70 Gy. The V_5 ,V_(10) ,V_(20) ,V_(30)and mean lung dose (MLD) were calculated from the dose volume histogram system. The RILI was evaluated according to Common Toxicity Criteria 3.0(CTC 3.0). Results The range of V_5 ,V_(10) ,V_(20) ,V_(30) was 37%-98%,27%-78%, 17%-54% and 9%-31%, respectively, with a median value of 65%, 47.5%, 31% and 24%, respectively. The acute RILI of grade 1, 2, 3, 4 and 5 was observed in 34, 27, 8, 1 and 1 patients,respectively. The chronic RILI of grade 1, 2 and 3 was observed in 46, 14 and 2 patients, respectively. V_5 ,V_(10) ,V_(20) and MLD were significantly correlated with acute RILI of ≥ grade 1. V_5 ,V_(20) ,V_(30) and MLD were significantly correlated with acute RILI of ≥ grade 2. The acute RILI of ≥ grade 2 was significantly in-creased when V_5, V_(20) and V_(30) were more than 65%, 31% and 24%, respectively. The acute RILI of ≥ grade 3 was significantly increased when V_5 was more than 65%. The acute RILI of ≥ grade 1 was signifi-candy increased when V_(20)was more than 31%. The gross tumor volume and planning target volume were sig-nificantly correlated with the acute RILI of ≥ grade 1 and chronic RILI of ≥ grade 2. Conclusions The dose-volume V_5 and V_(10) are effective in predicting RILI.