An Analysis Of Related Influencing Factors To Severeacute Radiation Pneumonitis In Patients With Lung Cancer

Objective：To investigate the related influencing factors to severe acute radiationpneumonitis in patients with lung cancer after radiotherapy.Methods：A total of154patients were collected from The First Affiliated Hospital ofNanchang University from February2011to September2013.multifactor Logisticregression was applied to analyze the relationship between incidence of severeacute radiation pneumonitis and15factors including gender,age,smokinghistory,clinical stage,pathological type,postoperative radiotherapy,the level ofhemoglobin and albumin before radiotherapy,chemotherapy cycle numbers beforeradiotherapy,concurrent chemoradiotherapy,The total dose of radiation and dosevolume factors (MLD, V5, V10, V20).Result：154cases of lung cancer patients after radiotherapy,35patients had≥3gradeof acute radiation pneumonia, the incidence rate was22.73%.Single factor analysisshowed:106cases of Patients with chemotherapy cycle number≤2times Beforeradiotherapy,19cases of radiation pneumonitis,48cases of Patients withchemotherapy cycle numbers>2times Before radiotherapy,16cases of radiationpneumonitis, the comparison between the two: χ2=4.438, P=0.035.18cases ofPatients with concurrent chemoradiotherapy,9cases of radiation pneumonitis,138cases of Patients without concurrent chemoradiotherapy,26cases of radiationpneumonitis, the comparison between the two: χ2=8.576, P=0.003.108cases ofPatients with MLD≤15Gy,13cases of radiation pneumonitis,46cases of Patientswith MLD>15Gy,22cases of radiation pneumonitis, the comparison between the two:χ2=23.375, P=0.000.95cases of Patients with V5≤40%,12cases of radiationpneumonitis,59cases of Patients with V5>40%,23cases of radiation pneumonitis,the comparison between the two: χ2=14.298, P=0.000.97cases of Patients with V10≤ 35%,15cases of radiation pneumonitis,57cases of Patients with V10>35%,20casesof radiation pneumonitis, the comparison between the two: χ2=7.821, P=0.005.87cases of Patients with V20≤25%,12people of radiation pneumonitis,67cases ofPatients with V20>25%,23cases of radiation pneumonitis, the comparison betweenthe two: χ2=9.030, P=0.003.Multivariate Logistic stepwise regression analysis showedthat:five factors (chemotherapy cycle number>2times before radiotherapy, treatedwith concurrent chemoradiotherapy, total dose of radiotherapy>56Gy,MLD>15Gy,V20>25%) could increase the risk of radiation pneumonitis in lung cancer patientsafter radiotherapy (P-value respectively was0.044,0.004,0.025,0.000,0.007, thedifference was statistically meaning).conclusion：Design of radiotherapy plan should satisfy the requiment of MLD≤15Gy andV20≤25%, The patients of the total of radiation dose greater than56Gy should bemore consistent with the requirements,but also patient’s individual factors includingchemotherapy history,concurrent chemoradiotherapy should be considered in order todecrease incidence rate of acute radiation pneumonitis.