Laryngeal edema after radiotherapy in patients with squamous cell carcinomas of the larynx and hypopharynx

Abstract

Significant laryngeal edema (SLE) after radiotherapy for squamous cell carcinoma of the larynx and hypopharynx may be associated with upper airway obstruction or tumor recurrence. We assessed the risk factors predictive of SLE and those differentiating tumor recurrence from SLE. We evaluated 127 patients with laryngohypopharyngeal squamous cell carcinomas who were primarily treated with radiotherapy with/without chemotherapy, had no previous major head and neck surgery, and underwent laryngoscopic examinations after radiotherapy. SLE was defined as RTOG grades ≥ 2 and patient characteristics and imaging, treatment and survival results were compared in patients with and without SLE. Of the 127 patients, 56 (44%) had SLE. Univariate analyses showed that tumor location, T and N classifications, overall stage, pathologic differentiation, and chemotherapy were significantly predictive of SLE (P<0.05). Multivariate analysis revealed that T classification remained an independent predictor of SLE (T1 vs. T2-4; odds ratio=5.070, 95% confidence interval=1.999-12.857; P=0.001). Twenty-seven (21%) patients had tumor recurrences, diagnosed by PET/CT (sensitivity 88%; specificity 92%) and CT (sensitivity 68%; specificity 88%). Twenty-seven patients with severe SLE were treated but only 9 (33%) had improvement. Tumor recurrence rate was higher (39% vs. 7%, P<0.001) and 3-year overall survival rate lower (54% vs. 87%, P<0.001) in patients with than without SLE. Patients with T2-4 laryngohypopharyngeal cancers are at higher risk of SLE development and tumor recurrence after radiotherapy that can be properly detected by (18)F-FDG PET/CT.