The Analysis of Relationship Between Radiation Pneumonuitis and DVH for NSCLC Treated with 3DCRT / 医学研究杂志

ABSTRACT

Objective To determine the relation between the incidence of radiation pneumonitis(RP) and available parameters from a dose-volume histogram(DVH) in patients with non-small cell lung cancer(NSCLC) who underwent three-dimensional conformal radiotherapy treatment.Methods Between January 1998 and December 2005 our hospital,62 patients with NSCLC were treated using three-dimensional conformal radiotherapy(3D CRT).All patients were treated 5 days per week with daily fractionation of 2 Gy to total dose of 60~70 Gy.All patients were available for analysis for symptomatic RP.Radiation pneumonitis was graded according to the RTOG/EORTC morbidity scoring classification.Logistic regression analysis was performed to test the association between RP and the following DVH parameters mean lung dose(MLD),volume of lung receiving 20 Gy(V20) and 30 Gy(V30) and normal tissue complication probability(NTCP).Additionally,correlation of the following clinical factors such as age,sex,tumor site,performance status(KPS),and additional therapy(chemotherapy) with incidence of the RP were performed.Results Thirty out of 62 patients(48%) developed RP grade 0 or 1(0 grade12%,1 grade36%) and 32(52%) grade 2 or 3(2 grade47%,3 grade5%).In the logistic regression analysis,all DVH parameters were associated with RP(p in range from 0.004 to 0.007).The strongest association was observed for NTCP and V30(P=0.004).Conclusion NTCP and V30 parameters were the best predictors of symptomatic radiation pneumonitis for patients after three-dimensional conformal radiotherapy of non-small cell lung cancer.