Are contouring time and multimodality imaging prognostic factors for radiation therapy of advanced head and neck cancer?

Material and methods Before 2007 radiation treatment planning-CT was done without contrast enhancement, MRI and F-FDG-PET/ CT were used only occasionally. From 2007 contrast enhanced planning-CT in addition to multimodality imaging was used routinely for every HNC. Additionally, in unclear or equivocal imaging findings of lymph nodes a re-report was performed with a higher sensitivity at the expense of specificity to minimise geographical miss in the contouring procedure for radiation treatment and to maximise the binary decisions for each lymph node (malignant vs. benign). The re-reports were done in conjunction with radio oncologists, nuclear physicians and radiologists. The mean contouring time was 60min before 2007, 150min after 2007 (including the time for a re-report). Clinical outcome was assessed in two groups (group I: 2001-2007, n=113 vs. group II: 2008-2012, n=94).