CO2 Laser Treatment of Pre-Cancerous Laryngeal Lesions Pre-cancerous laryngeal lesions refer to some laryngeal disorders with malignant potential, mainly including chronic hypertrophic hyperplastic laryngitis, laryngeal keratosis (also known as laryngeal leukoplakia), and laryngeal papilloma (adult type), which is generally considered to have a cancerous rate of about 3-10%. The histopathologic features of precancerous laryngeal lesions include epithelial hyperplasia and keratosis with varying degrees of hyperkeratosis and papillomatous hyperplasia. It is generally believed that epithelial atypical hyperplasia can be divided into three levels: mild, moderate and severe, and most of the laryngeal epithelial simple hyperplasia and mild atypical hyperplasia can be reversed after the disappearance of causative factors or symptomatic treatments, and the rate of cancerous transformation is relatively low. Severe atypical hyperplasia has a higher risk of cancer. From the process of lesion development, the epithelium with severe atypical hyperplasia has some qualitative differences in cell proliferation and division with mild and moderate atypical hyperplasia, and the biological morphology of the cells possesses the conditions to develop into cancerous cells, so it is necessary to intervene early in laryngeal pre-cancerous lesions. Previous scholars generally advocated conservative treatment or “wait and see” for pre-cancerous laryngeal lesions, and then aggressive surgical treatment when the lesions become cancerous. In our opinion, since there is no reliable testing index to evaluate the prognosis of the lesion, therefore, active intervention at the early stage of the lesion is an important means, and the application of CO2 laser surgery to remove the lesion has good efficacy and quick recovery, which can interrupt the development process, prevent the development of malignancy, and achieve the goal of cure. In the past 5 years, our department has treated 84 cases of chronic hypertrophic laryngitis, laryngeal keratosis and pre-cancerous laryngeal lesions such as laryngeal papilloma under general anesthesia and supportive laryngoscopy with CO2 laser, and the one-time cure rate was 85.7% (72/84), and there were 12 cases of postoperative recurrence, which accounted for 14.3% (12/84), among which there were 5 cases of laryngeal keratosis and laryngeal papilloma (adult type) which had malignant changes successively, and the percentage of these cases was 5.95% (5/5) and 5.95% (5/5) respectively. 5.95%(5/84). The postoperative follow-up of 1-5 years proved that CO2 laser treatment of laryngeal pre-cancerous lesions had the advantages of short operation time, fast voice recovery after the operation, and not easy to recur.