Radiation-induced Pneumonitis In Radiotherapy For Breast Carcinoma

Objective:To evaluate the toxicity in the lung induced by radiotherapy in patients with breast carcinoma and analyze the correlative factors .Methods:From January 2007 to January 2009,238 breast carcinoma patientstreated with radiotherapy were retrospectively reviewed at this hospital.IMRT were designed for each of 238patients by using the Cadplan 6.4.7 treatment planning system.The prescription dose was 50Gy.All took chest X-ray or CT scanning.Radiation-induced toxicity was diagnosed based on contrasted CT combined with clinical symptoms.The degree of radiation-induced toxicity was defined according to the criteria of RTOG. To analyze V20,MLD,Dmax were gained through dose-volume histograms(DVH)data was collected from three-dimensional conformal radiotherapy planning system,clinical date and physical date with clinical factors and physical parameters in relation to radiation-induced pneumonitis.Logistic regression model was used to test their relativities. Results:According to the Radiation therapy oncology group ( RTOG ) criteria,acute post-irradiation lung injury was observed 18cases(7.6%),Of these 238 patients, gradeâ… -16,gradeâ…¡-2. The correlative factors included: modus operandi,Pulmonary disease,continuation chemotherapy,Multilogistic regression analysis showed that modus operandi,Pulmonary disease were the independent inducing factors for pneumontis. Conclusion: modus operandi,Pulmonary disease,are significantly associated with the pneumonitis in breast carcinoma patients treated with radiotherapy.