Outcomes For Patients With Locally Advanced Hypopharyngeal Squamous Cell Carcinoma Treated With Definitive Radiation Using Intensity Modulated Radiation Therapy With Adaptive Planning

To report clinical outcomes of patients with locally advanced hypopharyngeal squamous cell carcinoma treated with definitive radiation therapy using IMRT with adaptive planning. We identified 30 patients with locally advanced hypopharyngeal head and neck squamous cell carcinoma who were treated with definitive radiation therapy between 2004 and 2014 at a single institution. 90% (27/30 patients) received concurrent chemotherapy and 83% (25/30) had stage IVa or IVb disease. Head and neck cancer patients treated at our institution undergo planned rescans at 15th RT fraction and are replanned if there is inadequate dose to gross disease or an increased dose to organs at risk. Disease and patient characteristics, treatment information, and clinical outcomes were tabulated for each patient. The median follow-up for these patients was 15.5 (Range: 5.2-104.4) months. Of the 30 patients, 10 (33.3%) developed loco-regional recurrence with 4 of these recurrences salvaged with laryngectomy/pharyngectomy with or without neck dissection. 13 patients (43.3%) developed metastatic disease. Two-year actuarial overall survival, progression-free survival, distant metastasis-free survival, locoregional control and laryngectomy-free survival for the entire cohort were 75%, 46%, 54%, 76% and 87%, respectively. Compliance with RT trended towards improved locoregional control with a hazard ratio for locoregional recurrence of 3.69 (95% CI: 0.96-14.17, P = 0.057) in patients with >5 missed treatment days. At time of last follow up, 56.7% (17/30) of all patients and 93.8% (15/16) of patients without disease recurrence were alive without need for tracheostomy and/or PEG tube. IMRT using adaptive planning results in good locoregional control and excellent functional outcomes in patients with locally advanced hypopharyngeal squamous cell carcinoma. Development of distant metastatic disease remains a significant problem for these patients and studies investigating ways to improve outcomes for these patients are warranted.