RATIONALE: Postoperative hypofractionated radiation is well established in many malignancies, yielding benefits in compliance, access to care, convenience, and cost savings. In several solid tumor types, short-course high dose-per-fraction (hypofractionated) post-operative radiation has shown excellent tolerability, reduced healthcare costs, improved compliance, and at least equivalent cancer control compared to conventional post-operative radiation (long course, low dose-per-fraction).(1-3) Despite advances in other malignancies, hypofractionated post-operative radiation is not used in previously untreated mucosal HNSCCs, for which an extended course of conventional post-operative radiation (usually 60 Gy in 2 Gy fractions delivered over six weeks) remains the standard. Hypofractionation has been stymied in the post-operative setting for HNSCCs primarily due to concerns of toxicity in treating a large mucosal field and an inability to spare critical structures such as the brain and spinal cord. These concerns were well-founded in the 1970s during the era of 2-dimensional radiotherapy when conventional HNSCC radiotherapy regimens were developed.(4) But because radiotherapy can be delivered far more precisely using intensity modulated radiation therapy (IMRT), it is hypothesized that post-operative radiation for HNSCCs can now be delivered safely in only five fractions delivered over one week.(3, 5, 6)
The primary purpose of this study is to determine the safe reduction of the treatment fractions to 10, 8, or 5, that may be delivered safely in resected head and neck squamous cell carcinoma (HNSCC) patients with intermediate pathologic risk features.