FDG PET studies during treatment: Prediction of therapy outcome in head and neck squamous cell carcinoma

BACKGROUND: Positron emission tomography (PET) provides metabolic information of tissues in vivo. The purpose of this study was to assess the value of PET with 2-(18) F fluoro-2-deoxy-D-glucose (FDG) in prediction of therapy outcome (tumor response, survival, and locoregional control) in locally advanced HNSCC. METHODS: Between 1993 and 1999 47 patients underwent PET before (PET(1)) and after (PET(2)) 1 to 3 weeks of radical treatment with evaluation of metabolic rate (MR) and standardized uptake value (SUV) of FDG. All patients received radiotherapy, and 10 also received neoadjuvant chemotherapy. Median follow-up time was 3.3 years. RESULTS: Low and high MR FDG at PET(2), with median value as cutoff, was associated with complete remission in 96% and 62% (p =.007), with 5-year overall survival in 72% and 35% (p =.0042) and with local control in 96% and 55% (p =.002), respectively. CONCLUSIONS: FDG PET in the early phase of treatment of HNSCC is associated with tumor response, survival, and local control.