Effectiveness of FDG-PET/CT for evaluating early response to induction chemotherapy in head and neck squamous cell carcinoma: A systematic review

BACKGROUND: (18)F-Fluoro-Deoxy-Glucose Positron Emission Tomography with Computed Tomography ((18)F-FDG PET/CT) may be a powerful tool to predict treatment outcome. We aimed to review the effectiveness of (18)F-FDG PET/CT in the assessment of early response to induction chemotherapy (IC) in patients with advanced Head and Neck Squamous Cell Cancer (HNSCC) without previous treatment. METHODS: PubMed, Cochrane Library, Science Direct and Web of Science were searched to May 2016. Reference lists of the included articles and additional studies identified by one nuclear medicine expert were screened for potential relevant studies that investigated the effectiveness of (18)F-FDG PET/CT performed before and after IC. Three authors independently screened all retrieved articles, selected studies that met inclusion criteria and extracted data. The methodology of the selected studies was evaluated by using the risk of bias checklist of the Agency for Healthcare Research and Quality (AHRQ). RESULTS: Seven out of 170 eligible studies met our inclusion criteria. A total of 207 advanced HNSCC patients were evaluated with (18)F-FDG PET/CT at baseline and after IC in the selected articles. Six from seven studies concluded that (18)F-FDG PET/CT allowed early evaluation response to IC and predicted survival outcomes. CONCLUSION: The present systematic review confirms the potential value of (18)F-FDG PET/CT as a diagnostic tool for early IV response assessment in HNSCC patients. However, the lack of standard definitions for response criteria and heterogeneous IC protocols indicate the need to further studies in order to better define the role of (18)F-FDG PET/CT in these patients.