Postoperative chemoradiotherapy with cisplatin is superior to radioimmunotherapy with cetuximab and radiotherapy alone: Analysis of the Austrian head and neck cancer registry of the AGMT

BACKGROUND: The addition of cisplatin or cetuximab to radiotherapy in patients with locally advanced squamous cell carcinoma of the head and neck (SCCHN) has significantly improved the outcome. While the superiority of cisplatin over cetuximab in combination with radiotherapy has been shown in a definitive setting, we set out to compare postoperative chemoradiotherapy with cisplatin to radioimmunotherapy with cetuximab and radiotherapy alone within the Austrian head and neck cancer registry of the Working Group on Pharmaceutical Tumor Treatment (AGMT) study group. MATERIAL AND METHODS: In the AGMT head and neck cancer registry, data of 557 patients with SCCHN from five Austrian cancer centers were prospectively collected between 2012 and 2017. Of these patients 120 received postoperative chemoradiotherapy with cisplatin, 26 patients received postoperative radioimmunotherapy with cetuximab and 56 patients were treated with adjuvant radiotherapy only. Patient characteristics, stage of disease, details on treatment as well as survival were analyzed by a chart-based review. RESULTS: In patients treated with postoperative radiotherapy the addition of cisplatin significantly improved progression-free survival (PFS) and overall survival (OS) compared to cetuximab (PFS 84.2 months vs. 17.0 months, p = 0.04, OS not reached vs. 46.0 months, p = 0.02) and PFS compared to radiotherapy alone (PFS 84.2 months vs. 28.5 months, p < 0.01). Patients treated with cetuximab were significantly older and had a worse performance score than patients receiving cisplatin or radiotherapy alone. CONCLUSION: This study confirmed the importance of multimodal treatment concepts in patients with locally advanced SCCHN. Postoperative cetuximab might be an option in patients not eligible for high-dose cisplatin but cisplatin should remain the standard of care.