Assessment of early tumor response to induction chemotherapy (IC) in locally advanced squamous-cell carcinoma of head and neck (LASCCHN) with 18FDG PET-CT: A prospective trial.

6017 Background: Response to IC with triplet regimens adding taxanes to cisplatin and 5-fluorouracil (TPF), followed by chemoradiotherapy (CRT) for LASCCHN, is usually evaluated after 2 cycles of IC, based on bidimensional WHO or modified WHO criteria. Concerns regarding toxicity profile of TPF suggest a potential benefit of an early response evaluation approach that could select patients who would be spared from a toxic regimen and promptly started on an alternative treatment. The aim of this study is to assess the ability of evaluating early response after the first IC cycle based on a 40% decrease in standard-uptake value (SUV) measured by 18 FDG PET-CT on the 14th day. Methods: Patients with LASCCHN who underwent IC with TPF were prospectively evaluated. Staging procedure included locoregional and chest imaging, endoscopic examination and FDG PET-CT. At day 14 of first cycle, a second FDG PET-CT was performed and treating physicians were blinded for these findings. All cases were conducted according t...