Postoperative accelerated radiotherapy (POPART) versus conventional postoperative radiotherapy (CPORT) in squamous cell head and neck cancer: A multicenter prospective randomized study of the Dutch Head and Neck Cooperative Study Group.

Abstract

5508 Background: In head and neck squamous cell carcinoma (HNSCC), the overall treatment time of radiation (OTT) is significantly associated with locoregional control (LRC), which is consistent with rapid repopulation of cancer clonogens during radiotherapy. However, the importance of the OTT in the postoperative setting is less clear. Therefore, the main objective of this phase III study was to determine the value of reduction of the OTT of postoperative radiotherapy in high risk patients primarily treated with surgery. Methods: Patients with HNSCC treated with curative surgery and with high risk factors for locoregional recurrence (i.e., positive surgical margins and/or extranodal spread) were randomly assigned to receive either standard postoperative radiotherapy (SPORT) at 2 Gy/fraction/day, 5 days/week to 66 Gy/33 fractions/7 weeks or postoperative accelerated radiotherapy (POPART) with 2 Gy/fraction/day, 5 days per week, to 20 Gy followed by 1.8 Gy/fraction/day and 1.3 Gy/fraction per day to a boost field as a second daily treatment to 66.5 Gy/40 fractions/5 weeks.The primary endpoint was locoregional tumor control (LRC). Secondary endpoints were overall survival, acute and late toxicity and quality of life. Results: From December 2004 to October 2008, 148 patients were enrolled in the study (74 pts for SPORT and 74 pts for POPART). The two study-arms were well balanced with regard to the most important prognostic factors. No significant differences were noted with regard to acute and late toxicity, although there was a trend towards more use of pain medication among patients treated with POPART. At 3 years, the locoregional control rate was 77% after POPART compared to 76% with SPORT (HR: 0.86, CI 0.42-1.76; p=0.68). The 3-year overall survival rate was 71% with POPART compared to 63% with SPORT (HR:0.93, CI 0.54-1.61; p=0.81). Conclusions: A reduction in the OTT of postoperative radiotherapy in patients with HNSCC with adverse factors for locoregional failure does not improve outcome in terms of locoregional control and overall survival. No significant financial relationships to disclose.