Incidence and mortality of laryngeal cancer in Zhejiang cancer registry, 2000-2011

Background: Laryngeal cancer is the one of the most prevalent cancer of the upper respiratory tract. Aiming to get a better understanding of the epidemiological characteristics and trends of laryngeal cancer in Zhejiang cancer registry in China during 2000-2011, we used the standardized quality control and statistical methods to analyze the incidence and mortality that were vital for making decision about laryngeal cancer prevention and control. Materials and Methods: Comparably high-quality data from eight population-based cancer registries in Zhejiang from 2000 to 2011 were qualified for analysis. The pooled data were stratified by area, sex, and age group. All incidence and mortality rates were age-standardized to the 2000 Chinese standard population and Segi's population, which were expressed per 100,000 populations. Average annual percent changes (AAPCs) and 95% confidence intervals of laryngeal cancer incidence and mortality were calculated for the temporal trends. The logarithmic trend line was also drawn to reflect the time trends of incidence and mortality. Results: During the 12 years, the 8 cancer registries covered a total of 81,758,277 person-year population (65,500,842 in urban and 16,257,435 in rural areas) including 41,315,911 person-year males and 40,442,366 person-year females. The age-standardized incidence rates were 1.10/10(5) by Chinese population and 1.12/10(5) by world population, respectively. The incidence of laryngeal cancer was relatively low in subjects under 44 years old. Then, it increased sharply after 45 years old and finally reached the peak in subjects of 75-79 years old. The age-standardized mortality rates of the Chinese population and world population were 0.28/10(5) and 0.35/10(5), respectively. The mortality of laryngeal cancer was at a low level in subjects under 49 years old. The rate dramatically increased in subjects over 50 years old, and then peaked in the age group of 80-84 years. The crude incidence of laryngeal cancer in Zhejiang cancer registration areas in 2000 was approximately 1.39/10(5), and it reached 1.78/10(5) in 2011, with the AAPC of 2.47%; the temporal trend line indicates that the incidence remained steady during the 12 years. The crude mortality of laryngeal cancer in Zhejiang registration areas in 2000 was about 0.30/10(5) and increased to 0.66/10(5), with the AAPC of 4.24% which showed no statistical significance; the temporal trend line indicates that mortality was going up to a certain extent, but not evident. Conclusions: Laryngeal cancer significantly influenced the quality of life for the patients. The comprehensive measures should be carried out to prevent the upward trend of laryngeal cancer.