Clinical, dosimetric, and position factors for radiation-induced acute esophagitis in intensity-modulated (chemo)radiotherapy for locally advanced non-small-cell lung cancer

Abstract

Purpose: The purpose of this study was to estimate the relation between acute esophagitis (AE) and clinical, dosimetric, and position factors in patients with locally advanced non-small-cell lung cancer (NSCLC) receiving intensity-modulated (chemo)radiotherapy.

Materials and methods: A retrospective cohort analysis was performed to identify factors associated with Common Toxicity Criteria for Adverse Events grade 2 or worse AE (AE2+). A multivariable model was established including patient- and treatment-related variables and esophageal dose-volume histogram parameters. The esophagus was divided according to physiological anatomy, and logistic regression was used to analyze the position parameter for its correlation with AE2+.

Results: The incidence of AE2+ was 27.5%. All models included gender, concurrent chemo-radiotherapy (CCRT), position parameter, and one of the dosimetric variables. The model with mean dose showed the best goodness of fit. Gender (OR=2.47, P=0.014), CCRT (OR=3.67, P=0.015), mean dose (OR=1.33, P<0.001), and maximum radiation position (OR=1.65, P=0.016) were significantly related to AE2+.

Conclusion: Gender, concurrent chemotherapy, maximum radiation position, and mean dose were independent risk factors for AE2+. The upper part of the esophagus showed a higher sensitivity to radiation toxicity.

Keywords: acute esophagitis; intensity-modulated radiation therapy; non-small-cell lung cancer; position parameter.

Figure 1

Sagittal section illustrating delineation of the cervical esophagus (pink), the upper thoracic esophagus (purple), the mid-thoracic esophagus (orange), and the lower thoracic esophagus (yellow).