Abstract
CONTEXT: Intensity-modulated radiation therapy (IMRT), three-dimensional conformal radiation therapy (3DCRT), and proton-beam therapy (PBT) are chemoradiotherapy modalities for treating locally advanced non-small-cell lung cancer. Although therapy is carefully planned to maximize treatment benefit while minimizing risk for adverse side effects, most patients develop radiation-induced symptom burden. OBJECTIVES: To demonstrate the MD Anderson Symptom Inventory's ability to detect fine differences in symptom development among these modalities. METHODS: This was a longitudinal observational study. Patients with unresectable primary or recurrent non-small-cell lung cancer (n = 82) underwent 3DCRT, IMRT, or PBT. Patients rated MD Anderson Symptom Inventory symptoms weekly for up to 12 weeks. We used mixed-effect modeling to estimate development of symptoms and functional interference. RESULTS: The PBT group received a significantly higher radiation target dose than did the IMRT and 3DCRT groups (P < 0.001). Fatigue was the most severe symptom over time for all groups. Controlling for patient and clinical factors (age, sex, race, cancer stage, performance status, body mass index, previous cancer therapy, total radiation dose), we found that pain, as a major esophagitis-related symptom, increased more during therapy (P = 0.019) and decreased more after (P = 0.013) therapy in the 3DCRT and IMRT groups than in the PBT group. Compared with the PBT group, the 3DCRT and IMRT groups reported greater decrease in systemic symptoms (fatigue, drowsiness, lack of appetite, disturbed sleep) after therapy (P = 0.016). CONCLUSION: Patients receiving PBT reported significantly less severe symptoms than did patients receiving IMRT or 3DCRT. These results should be confirmed in a randomized study with comparable tumor burden among therapies.