The aim of the present study was to analyze the association between laryngeal cancer and vocal cord leukoplakia in a large nationwide practice database. The study sample included 1,184 patients aged 18-90 years from 113 otorhinolaryngology practices in Germany who were diagnosed with vocal cord leukoplakia between 2007 and 2014. The rates of laryngeal cancer diagnosis within 5 years and the associated risk factors were analyzed. Within 6 months of initial diagnosis of vocal cord leukoplakia, 11% of the patients were diagnosed with laryngeal cancer. Between 7 months and 5 years after the diagnosis of leukoplakia, laryngeal cancer was diagnosed in 7.6% of the patients. Overall, within 5 years of leukoplakia diagnosis, 18.6% of the patients were diagnosed with laryngeal cancer (26.1% of men and 6.3% of women; P<0.001). Moreover, 31.3% of patients aged >65 years, 16.1% of patients aged 50-65 years and 7.6% of patients aged <50 years were diagnosed with laryngeal cancer (P<0.001). Patients aged >65 and those aged 50-65 years had a higher risk of being diagnosed with laryngeal cancer [odds ratio (OR)=4.90 and 2.55, respectively]. Furthermore, the risk of being diagnosed with laryngeal cancer was higher in men compared with that in women (OR=4.09). In the present real-world analysis, the rate of laryngeal cancer underlying vocal cord leukoplakia at first diagnosis appeared to be higher compared with the secondary malignant transformation rate occurring later during the course of the disease. Risk factors for laryngeal cancer included advanced age and male sex.
Keywords: incidence; laryngeal cancer; larynx; leukoplakia; nationwide practice database; otorhinolaryngology practices; risk factors.