A study on the esophageal cancer radiotherapy effects on the patient’s lung health

Introduction:   Radiotherapy with or without surgery plays an important role in the treatment of patients with esophageal cancer. In the treatment planning of esophageal cancer, usually normal lung volume was observed in the treatment fields and probably received high radiation dose. The incidence of radiation pneumonitis (RP) after radiotherapy (RT) for sensitive organ of lung is predictable. In this study some clinical and dose-volume factors were presented to identify patients at risk of radiation pneumonitis. Materials and Methods: Patients with esophageal cancer who candidate for radiotherapy were tested for symptoms of lung disease including cough, chest pain, fever before and after radiotherapy by physician. Patient properties and history included age, sex, surgery and smoking history were recorded. Dose-volumetric parameters such as lung volume, mean lung dose (MLD), and lung percent that receiving dose of 5-50Gy (V5-V50) extracted from dose-volume histogram. Results: Seventeen women and thirteen men with median age of 63.3 and 69 years studied. The incidence of radiation pneumonitis was 16.7 % in patients who received pre-operative RT with total dose of 50.4 Gy (28 fractions). The results showed that age (<65 or ≥65) and V35 (<14 or ≥14 %) significantly associated with RP incidence in patients treated with pre- operative radiotherapy. Patient properties did not show clear positive or negative correlation with radiation pneumonitis Conclusion: Whereas patients with esophageal cancer who received radiotherapy usually did not follow up for radiation pneumonitis, this study suggests that limit the dose-volume parameters to threshold values can be beneficial to reduce the risk of radiation pneumonitis.