Harnessing nanoparticles to improve toxicity after head and neck radiation.

This article reports the evaluation of cerium oxide (CeO(2)) nanoparticles' ability to decrease xerostomia and radiation-induced dermatitis in mice after head and neck radiation. Mice were irradiated using an IC160 x-ray system. Two cohorts were included: (A) No-radiation and (B) 30 Gy/6 fractions, and were randomized into three groups: (1) saline, (2) 15 nM CeO(2) and (3) 15 μM CeO(2). Stimulated salivary flow and radiation-induced dermatitis were evaluated post radiation. Stimulated sialometry demonstrated improved salivary production in all CeO(2) groups in comparison with controls (flow: 204 vs. 115 μL/10 minutes, P = 0.0002). One week post radiation, G-III dermatitis decreased in the 15 μM group in comparison with controls (10% versus 100% incidence, respectively). There was decreased skin hyperpigmentation at 12 weeks in the 15-μM group in comparison with 15-nM and non-CeO(2) groups (50%, 70%, and 90% G-II, respectively). This study suggests that CeO(2) may be radioprotective for salivary production and reduces G-III dermatitis and skin hyperpigmentation incidence. CeO(2) as radioprotectant may be a feasible concept during radiotherapy. FROM THE CLINICAL EDITOR: This study demonstrates in a mouse model that cerium oxide (CeO(2)) nanoparticles may provide an important mechanism in preventing radiation induced xerostomia, a common complication of head and neck radiation treatments.