Dyspnea evolution after high-dose radiotherapy in patients with non-small cell lung cancer.

Purpose: To determine what the influence is of dyspnea (CTCAE3.0) before high-dose radiotherapy (RT) on the incidence and severity of subsequent lung toxicity in patients with non-small cell lung cancer (NSCLC).

Methods: In 197 patients with stage I-III NSCLC maximal dyspnea scores (CTCAE3.0) were obtained prospectively at three time periods: before RT, the first 6 months post-RT and 6-9 months post-RT. Only patients who were clinically progression-free 12 months or more after RT were included, thus minimizing dyspnea due to tumor progression. Time-trends of dyspnea as a function of baseline dyspnea were investigated and correlated with gender, age, chemotherapy, mean lung dose (MLD), lung function parameters (FeV1 and DLCO), stage, PTV dose, overall treatment time and smoking habits.

Results: The proportion developing less, the same or more dyspnea 6-9 months post-treatment according to their baseline dyspnea scores was: Grade 0: none, 82.9%, 17.1%; Grade 1: 21.2%, 51.9%, 26.9%; Grade 2: 27.3%, 54.5%, 18.2%, respectively. Only age was associated with increased dyspnea after RT.

Conclusions: Patients with dyspnea before therapy have a realistic chance to improve after high-dose radiotherapy. Reporting only dyspnea at one time-point post-RT is insufficient to determine radiation-induced dyspnea.