Evaluation of Concomitant Systemic Treatment in Older Adults With Head and Neck Squamous Cell Carcinoma Undergoing Definitive Radiotherapy
Authors: Rühle Alexander , Marschner Sebastian , Haderlein Marlen , Fabian Alexander , Weymann Maria , Behrens Max , Senger Carolin , Dickstein Daniel R. , Kraft Johannes , von der Grün Jens , Chen Eric , Aquino-Michaels Todd , Domschikowski Justus , Bickel Amanda , Altay-Langguth Alev , Kalinauskaite Goda , Lewitzki Victor , Ferentinos Konstantinos , Zamboglou Constantinos , Schnellhardt Sören , Haehl Erik , Spohn Simon K.B. , Gkika Eleni , Zöller Daniela , Guckenberger Matthias , Budach Volker , Belka Claus , Bakst Richard , Mayer Arnulf , Schmidberger Heinz , Grosu Anca-Ligia , Balermpas Panagiotis , Stromberger Carmen , Nicolay Nils H. 
Published: February 2023

ImportanceThe number of older adults with head and neck squamous cell carcinoma (HNSCC) is increasing, and these patients are underrepresented in clinical trials. It is unclear whether the addition of chemotherapy or cetuximab to radiotherapy is associated with improved survival in older adults with HNSCC.ObjectiveTo examine whether the addition of chemotherapy or cetuximab to definitive radiotherapy is associated with improved survival in patients with locoregionally advanced (LA) HNSCC.Design, Setting, and ParticipantsThe Special Care Patterns for Elderly HNSCC Patients Undergoing Radiotherapy (SENIOR) study is an international, multicenter cohort study including older adults (≥65 years) with LA-HNSCCs of the oral cavity, oropharynx/hypopharynx, or larynx treated with definitive radiotherapy, either alone or with concomitant systemic treatment, between January 2005 and December 2019 at 12 academic centers in the US and Europe. Data analysis was conducted from June 4 to August 10, 2022.InterventionsAll patients underwent definitive radiotherapy alone or with concomitant systemic treatment.Main Outcomes and MeasuresThe primary outcome was overall survival. Secondary outcomes included progression-free survival and locoregional failure rate.ResultsAmong the 1044 patients (734 men [70.3%]; median [IQR] age, 73 [69-78] years) included in this study, 234 patients (22.4%) were treated with radiotherapy alone and 810 patients (77.6%) received concomitant systemic treatment with chemotherapy (677 [64.8%]) or cetuximab (133 [12.7%]). Using inverse probability weighting to attribute for selection bias, chemoradiation was associated with longer overall survival than radiotherapy alone (hazard ratio [HR], 0.61; 95% CI, 0.48-0.77; P &amp;lt; .001), whereas cetuximab-based bioradiotherapy was not (HR, 0.94; 95% CI, 0.70-1.27; P = .70). Progression-free survival was also longer after the addition of chemotherapy (HR, 0.65; 95% CI, 0.52-0.81; P &amp;lt; .001), while the locoregional failure rate was not significantly different (subhazard ratio, 0.62; 95% CI, 0.30-1.26; P = .19). The survival benefit of the chemoradiation group was present in patients up to age 80 years (65-69 years: HR, 0.52; 95% CI, 0.33-0.82; 70-79 years: HR, 0.60; 95% CI, 0.43-0.85), but was absent in patients aged 80 years or older (HR, 0.89; 95% CI, 0.56-1.41).Conclusions and RelevanceIn this cohort study of older adults with LA- HNSCC, chemoradiation, but not cetuximab-based bioradiotherapy, was associated with longer survival compared with radiotherapy alone.