Definitive Intensity-modulated Radiation Therapy in Elderly Patients with Locally Advanced Oropharyngeal Cancer

Background: To evaluate the treatment tolerance and clinical outcomes in patients aged 70 years and older with locally advanced oropharyngeal cancer treated by definitive intensity-modulated radiation therapy (IMRT). Patients and Methods: We retrospectively analyzed 15 consecutive elderly patients, with histologically-proven squamous cell carcinoma of the oropharynx, staged T3-4 with or without involved lymph nodes at diagnosis, who received definitive sequential IMRT (70 Gy; 2 Gy/fraction). Adult Comorbidity Evaluation-27 (ACE-27) score was calculated and its influence on treatment tolerance and clinical outcomes was analyzed. Results: A total of 15 patients were included with a median age of 77 years (range=70-88 years). At baseline, 8 patients (53.3%) had an ACE-27 score of 1, and the remainder (n=7, 46.7%) had a comorbidity index of 0. All patients completed programmed IMRT treatment, without any reduction of total dose. Oral pain and mucositis were the most common acute side-effects, classified as grade 3 in 6 patients (40%) only. Xerostomia was reported in 13 patients (86.7%), without severe manifestation. There was no hematological toxicity. ACE-27 score was not related to higher severe acute toxicity. No patients experienced grade 3 or more late toxicity. Five-year overall survival and disease-free survival rates were 63.6% (95% confidence interval=32.7-83.3%) and 55% (95% confidence interval=24.4-77.6%), respectively. Comorbidity score did not influence survival outcomes, both overall survival (p=0.46) and disease-free survival (p=0.55). Conclusion: Treatment tolerance, as well as survival outcomes were good in elderly oropharyngeal cancer patients treated with definitive sequential IMRT. Due to age and comorbidity, no dose or volume reduction for IMRT should be considered in this setting of patients. A prospective randomized trial with a large sample size should be conducted to confirm our results.