Intensity Modulated Hyperfractionated Accelerated Radiotherapy to Treat Advanced Head and Neck Cancer - Predictive Factors of Overall Survival
Abstract
Aim: The aim of this study was to evaluate overall survival (OS) and prognostic factors in patients ineligible for chemotherapy who were treated with a hyperfractionated accelerated schedule with simultaneous integrated boost. Material and Methods: From May, 2008, to April, 2013, 122 patients with locally advanced nonmetastatic squamous laryngeal (14%), hypopharyngeal (30%), oropharyngeal (30%), and oral cavity (27%) cancer were treated at our institution.
The median age, Karnofsky Performance Status (KPS), and gross tumor volume (GTV) of the patients were 63 years (range, 46-87 years), 80% (range, 50-100%), and 46 ml (range, 5-250 ml), resp. The median total dose of radiotherapy was 72.6 Gy (range, 62-77 Gy) at 1.4-1.5 Gy per fraction, and 55 Gy at 1.1 Gy per fraction was delivered for GTV (primary and lymphadenopathy) with a margin of 0.7 cm and regional lymphatic areas with a margin of 0.3 cm.
The dose was delivered 2x a day, with a 6-8 hour interval between doses, via a 6 MeV linear accelerator. OS was estimated using the Kaplan-Meier method, and predictors of OS were analyzed using Cox proportional hazards regression.
Results: The median duration of the radiotherapy series was 37 days (range, 32-45 days). The incidence of grade 3 acute toxicity was 62% for mucosa (oral cavity and/or pharynx) and 0% for skin.
Confluent mucositis cleared in all cases within 21 days. No grade 4 or 5 toxicities were recorded.
PEG was introduced before treatment in 55 patients (45%). The 1- and 2-year OS was 65% and 32%, resp.
KPS less than 80% (RR 2.4, 95% CI 1.3-4.2; p = 0.004), cancers other than oropharyngeal or laryngeal cancer (RR 2.0, 95% CI 1.1-3.5; p = 0.016), and capacity of high GTV (RR 1.006, 95% CI 1.001-1.011; p = 0.017) were found to be negative prognostic factors for OS. Conclusion: More than 30% of patients with poor prognosis survived for longer than 2 years.
KPS before treatment was the strongest prognostic factor for better OS.