larynxcancer.ppt

Larynx Cancer Epidemiology Incidence Rate is increasing year by year . 据报道，中国喉癌的发病率占全身恶性肿瘤的2%~8%，占耳鼻咽喉恶性肿瘤的14%~33%。 中国喉癌的年死亡率： 2/10万－4．4/10万。按全国13亿人计算，每年约2.6万～5.7万人死于喉癌！ Each year, 11,000 new cases of larynx cancer will be diagnosed in the United States (1% of new cancer diagnoses), and approximately one third of these patients will die of their disease. Area Difference Domestic data Northeast area is higher than others. City is higher than countryside. Heavy industry area is higher than light industry area. Overseas data Higher region of disease : Italian, Brazilian, Indian Lower region of disease: Denmark, Norway Sexual Difference：mal : femal=5-10:1 Age Difference: 50-69 years In USA, the current male-to-female ratio for larynx cancer is 4:1, but the relative percentage of women with this, as with other smoking-related illness, has been on the rise. Larynx cancer is most prevalent in the sixth and seventh decades of life and is more prevalent among lower socioeconomic groups, for whom it is often not diagnosed until more advanced stages. Etiology Heavy Tobacco and Alcohol Use More than 90% of patients with larynx cancer have a history of heavy tobacco and alcohol use. Cigarette smoke, in particular, is a risk factor for cancer of the larynx. The combination of smoking and alcohol use has a more additive carcinogenic effect on the larynx. Other risk factors have been identified. Laryngeal infection with the human papillomavirus (HPV) results in laryngeal papillomatosis, which is usually benign, but subtypes 16 and 18 are known to degenerate into SCC. Gastroesophageal reflux has been implicated; however, a causal relationship with laryngeal cancer is still uncertain, although therapies directed at suppressing acid appear to decrease the recurrence of laryngeal cancer. Various occupational exposures and toxic inhalations (such as asbestos and mustard gas), nutritional