▶ Jo Jae-gu, Professor of Otolaryngology, Head and Neck Surgery, Korea University Guro Hospital
Cho Jae-gu, a professor of otolaryngology and head and neck surgery at Korea University Guro Hospital, emphasized, “If the hoarse voice lasts for more than two weeks, it is highly likely that there is a problem with the larynx, including laryngeal cancer, so it is better to visit a hospital and get a diagnosis.” [고려대 구로병원 제공]
The larynx (喉頭), located in the center of the neck, is an organ that produces voices and acts as a breathing path (airway). It also protects the airways and lungs by preventing foreign substances and secretions from entering the airways.
Laryngeal cancer is a malignant tumor that occurs in the larynx. Among head and neck cancers that occur between the bones under the brain, it has the second highest prevalence after oral cancer. Laryngeal cancer accounts for about 0.6% of all cancers, and the number of patients per 100,000 is about 3 to 4, but it occurs most frequently from the age of 50, with the largest number of patients in their 60s and 80s. I met a professor of nasopharyngeal and head and neck surgery. Professor Cho said, “If you have a hoarse voice for more than two weeks and have symptoms of shortness of breath while eating, it is better to suspect laryngeal cancer and go to the hospital.”
– What are the symptoms of laryngeal cancer?
The most characteristic symptom of laryngeal cancer is a change in voice. If the surface of the vocal cords becomes even slightly irregular, the voice changes. If you develop laryngeal cancer, your voice can change slowly and seriously.
Laryngeal cancer also spreads along the lymph glands to the neck, so you may feel a lump in your throat or a feeling that there is a foreign body stuck in your throat. Difficulty swallowing food and sore throat. You may also hear a noise in your throat when you breathe or breathe, especially when you breathe in. Smoking is a major causative factor, as 95% of cases of laryngeal cancer are related to smoking. When numerous harmful substances present in tobacco are chronically in contact with the laryngeal mucosa, mucosal cells mutate and grow disorderly, resulting in cancer. Drinking alcohol together increases the risk of cancer by three to four times.
– How is the treatment going?
The cure rate for laryngeal cancer is 90% at stage 1, 80% at stage 2, 50% at stage 3, and 40% at stage 4, so the treatment rate decreases as the stage progresses. If detected early, the prognosis is good. Since the larynx performs various important functions such as breathing, eating, and talking, it is important to preserve its function as much as a cure for cancer. Therefore, if possible, extensive resection should be avoided and efforts should be made to preserve function. For this, radiation therapy and chemotherapy are performed along with surgery.
The principle of laryngeal cancer surgery is to completely excise the cancerous tissue, but preserve the normal tissue as much as possible to preserve the laryngeal function. The scope and method of surgery vary depending on the degree of laryngeal cancer progression. In the early stages of laryngeal cancer, excise the larynx through the mouth and excise it with a laser while viewing it under a surgical microscope, or perform partial laryngeal resection, which removes only a part of the larynx by excising the skin of the neck from the outside.
However, advanced cancer requires removal of all or a significant portion of the larynx. If detected at an early stage and part of the laryngeal mucosa is excised under a surgical microscope, the voice can be preserved as much as possible and the cure rate is very high. However, in advanced laryngeal cancer, the entire larynx is removed or only a portion is left. In this way, if the lesion removal operation is performed, the quality of life is very different because the voice is completely lost or only a voice that is difficult to communicate is left. In early laryngeal cancer, radiation therapy preserves the normal structure and function of the vocal cords as much as possible. On the other hand, if the cancer is advanced, radiation therapy is performed to remove the remaining cancer cells after surgery.
– Management of laryngeal cancer after treatment is also important.
The biggest functional problem that occurs after laryngeal cancer treatment is dysphonia and swallowing disorders. Vocalization and swallowing are both very important for daily living and should be as important as surgery. If a partial laryngeal resection has been performed, the vocal cords remain and preserve the voice, but the protective function of the larynx airway is poor, so sare (pulmonary aspiration) may occur when eating. Swallowing rehabilitation training takes place two to three weeks after surgery, and caution should be exercised as it may cause pneumonia.
If total laryngeal resection is performed, normal vocalization is impossible. In this case, in order to produce a voice, a vibration-generating area is needed instead of the vocal cords, so voice rehabilitation is required, such as vibrating the esophageal sphincter or using an electric larynx that artificially generates vibration. Recently, artificial vocal cords are inserted to help vocalization.
– Let’s talk about how to prevent laryngeal cancer.
The surest way to prevent this is to quit smoking. After 6 years of quitting smoking, the incidence of laryngeal cancer significantly decreases, and after 15 years, the incidence becomes similar to that of nonsmokers. So, if you are a smoker, it is best to quit as soon as possible. As with other cancers, early detection of laryngeal cancer increases the survival rate, so early detection is very important. In particular, the earlier laryngeal cancer is detected, the more vocal cords can be preserved, so it is recommended that people in their 40s and 50s who smoke and drink frequently visit an otolaryngologist at least once a year to check the health of the larynx.
Kwon Dae-ik Medical Specialist reporter>
