Abstract
Background and purposePatients with locally advanced oropharynx squamous cell carcinoma have suboptimal outcomes with standard chemoradiation. Here, we evaluated toxicity and oncologic outcomes of dose escalation using radiosurgical boost for patients with unfavorable oropharynx squamous cell carcinoma.Materials and methodsBetween 2010–2017, Thirty four patients with intermediate- or high-risk oropharynx squamous cell carcinoma were enrolled onto this prospective phase I trial. Each patient received concurrent cisplatin and fractionated radiotherapy totaling 60 Gy or 66 Gy followed by radiosurgery boost to areas of residual gross tumor: single fraction of 8 Gy or 10 Gy, or two fractions of 5 Gy each. Primary endpoint was treatment toxicity. Secondary endpoints were local, regional, and distant disease control.ResultsEleven, sixteen and seven patients received radiosurgery boost with 8 Gy in 1 fraction, 10 Gy in 1 fraction, and 10 Gy in 2 fractions respectively. Acute toxicities include 4 patients with tumor necrosis causing grade 3 dysphagia, of which 3 developed grade 4 pharyngeal hemorrhage requiring surgical intervention. At 24 months after treatment, 7%, 9%, and 15% had grade 2 dysgeusia, xerostomia, and dysphagia, respectively, and two patients remained feeding tube dependent. No grade 5 toxicities occurred secondary to treatment. Local, regional, and distant control at a median follow up of 4.2 years were 85.3%, 85.3% and 88.2%, respectively. Five patients died resulting in overall survival of 85.3%.ConclusionsThis study is the first to report the use of radiosurgery boost dose escalation in patients with unfavorable oropharynx squamous cell carcinoma. Longer follow-up, larger cohorts, and further refinement of boost methodology are needed prior to implementation in routine clinical practice.Trial Registration: Northwell Health Protocol #09-309A (NCT02703493) (https://clinicaltrials.gov/ct2/show/NCT02703493)
Highlights
Locoregional control rates after curative radiation therapy for patients with oropharynx (OP) squamous cell carcinoma (SCC) unassociated with human papilloma virus (HPV) or those with prolonged tobacco exposure are significantly lower than the 80% local control ratesVempati et al Radiat Oncol (2020) 15:278 expected for HPV-associated disease [1,2,3]
This study is the first to report the use of radiosurgery boost dose escalation in patients with unfavorable oropharynx squamous cell carcinoma
Treatment failure in these patients is often confined to the radiotherapy field, suggesting that a subpopulation of tumor cells may be resistant to standard radiation doses, and that a higher therapeutic index may be required for effective local control [7, 8]
Summary
Locoregional control rates after curative radiation therapy for patients with oropharynx (OP) squamous cell carcinoma (SCC) unassociated with human papilloma virus (HPV) or those with prolonged tobacco exposure are significantly lower than the 80% local control ratesVempati et al Radiat Oncol (2020) 15:278 expected for HPV-associated disease [1,2,3]. Other studies treating patients with HPV-negative disease with chemoradiotherapy have shown poor outcomes with locoregional failure rates at 2 to 3 years ranging between 33% and 74% [4,5,6,7] Treatment failure in these patients is often confined to the radiotherapy field, suggesting that a subpopulation of tumor cells may be resistant to standard radiation doses, and that a higher therapeutic index may be required for effective local control [7, 8]. Preclinical studies suggest that the unique effect of single high dose SRS may be driven by ceramide-mediated apoptosis and alterations of tumor vasculature [8, 10] To this end, a small number of retrospective studies have reported improved local control in patients with OP SCC receiving SRS boost after IMRT, and their functional and toxicity outcomes were acceptable [11,12,13,14,15]. We evaluated toxicity and oncologic outcomes of dose escalation using radiosurgical boost for patients with unfavorable oropharynx squamous cell carcinoma
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
