Moderately accelerated intensity-modulated radiation therapy using simultaneous integrated boost: practical reasons or evidence-based choice? A critical appraisal of literature

Concurrent chemo-radiotherapy is the non-surgical mainstay of treatment for locally advanced head and neck squamous cell carcinoma (HNSCC). The following aspects have emerged as fundamental components of the combined approach: first, intensity modulated radiotherapy (IMRT) is the minimum standard technical requirement, with level 1 evidence in support of its reduction of late treatment-induced morbidity in comparison with 3D conformal radiotherapy. Second, cisplatin-based chemotherapy is the preferred systemic agent to be associated with radiation, with 100 mg/m2 every 3 weeks deemed as the reference schedule. Because of significant progress in irradiation techniques achieved in last 15 years, the optimal fractionation schedule in modern radiation era remains controversial, especially for locally advanced disease. The purpose of this work was to perform a critical review on the value of moderately accelerated IMRT using simultaneous-integrated boost (SIB) in HNSCC, aiming to provide insights on current clinical practice and directions for future research.