Multivariate analysis of elderly patients with thoracic malignancies caused by radioactive radiation pneumonitis

Objective To investigate elderly patients with thoracic radiotherapy nausea result after risk factors associated with radiation pneumonitis. Methods The clinical data of a total of 440 cases of cancer patients with chest radiation therapy during January 2010-January 2014 were collected retrospectively. Of them, 76 cases of radiation pneumonitis after radiotherapy were compared with other patients. The unconditional Logistic regression analysis was used to analyze the relationship of radiation pneumonitis and different factors including smoking, pulmonary dysfunction, combination with chemotherapy, radiation dose, and radiation sites. Results Elderly incidence of radiation pneumonitis was 17.27%. Multivariate Logistic regression analysis revealed the chi-square value of smoking, pulmonary dysfunction, combined with chemotherapy, radiation dose, and radiation sites was significant correlation (χ2=16.936, 19.633, 11.531, 17.133, 10.178, P<0.05), and the correlation degree was gradually decreased from pulmonary dysfunction, radiation dose, smoking, combined chemotherapy, to radiation site. Conclusions Elderly patients with thoracic malignancies after radiotherapy had more radiation pneumonitis, which was related to smoking, previous chemotherapy PO2<80%, combined with chemotherapy, radiation dose ≥55 Gy, and low-lung radiation. The correlation degree was gradually decreased from chemotherapy before PO2<80%, the radiation dose ≥55 Gy, smoking, combined chemotherapy, to low-lung radiation. Key words: Thoracic neoplasms/RT; Radiation pneumonitis; Risk factors