Impact of metformin on patients with advanced head and neck cancer undergoing concurrent chemoradiotherapy

Background The purpose of this study was to evaluate the impact of metformin on toxicities and survival in patients with head and neck cancer undergoing concurrent chemoradiotherapy (CRT). Methods We retrospectively analyzed and compared the clinical characteristics, treatment tolerance, toxicities, and survival of 252 patients with stages III, IVA, and IVB head and neck cancer undergoing concurrent CRT with and without metformin treatment between 2007 and 2010. Results Among all patients, 39 patients received metformin whereas 219 patients did not. Both groups had similar clinical characteristics and nearly identical disease-free survival and overall survival. However, the metformin group was less likely to tolerate cisplatin, experienced more weight loss, had a tendency to receive lower doses of radiotherapy, required more feeding tube support, and had grade ≥3 nausea/vomiting and hematological toxicities. Conclusion Patients with head and neck cancer undergoing concurrent CRT along with metformin treatment require more careful multidisciplinary assessment and supportive care to ensure successful completion of treatment and avoid treatment-related toxicities.