N-methylnitrosourea–induced carcinoma as a model for laryngeal carcinogenesis.

BACKGROUND Preclinical animal models to study laryngeal cancer are nonexistent. The purpose of this study was to describe a novel mice laryngeal cancer model. METHODS A total of 18 six-week-old A/J mice were used. Animals underwent microdirect laryngoscopy, superficial larynx scratching, and instillation of N-methyl-N-nitrosourea (MNU) at 2 different concentrations (15 μL and 30 μL) or dimethyl sulfoxide (DMSO) to the control group directly to the larynx. Mice received a total of 5 instillations of MNU or DMSO at 1-week intervals. Mice were euthanized at 20 and 30 weeks after the last intervention and laryngeal histology was analyzed. RESULTS Laryngeal instillation of MNU caused a 60% cancer conversion in the study group. CONCLUSION Our findings demonstrate the feasibility of developing a murine laryngeal carcinogenesis model using direct topical instillation of MNU. This is the first murine model of laryngeal cancer and has great potential for evaluating new agents for chemoprevention and treatment for laryngeal carcinoma.