Nasopharyngoscopy cannot detect laryngeal cancer. Nasopharyngoscope is an instrument used to examine the nasopharynx, which can detect nasopharyngeal cancer, but generally cannot detect laryngeal cancer. Laryngeal cancer needs to be diagnosed through laryngoscopy and pathological tissue biopsy. Pathological tissue biopsy is the gold standard for diagnosing laryngeal cancer. Generally, through laryngoscopy, a suspicious lesion can be seen, and then an appropriate amount of pathological tissue can be taken for biopsy analysis. Laryngeal cancer is a malignant tumor that occurs in the larynx. The cause of laryngeal cancer is still unclear, and it may be related to viral infection, heredity and tobacco and alcohol addiction. Common clinical symptoms include hoarseness, dyspnea, foreign body sensation and pain in the throat. When patients have symptoms such as foreign body sensation and pain in the throat, they should go to the hospital in time for examination to clarify the cause of the disease, and carry out relevant examinations and treatments under the guidance of doctors.