I. What is oral cancer
Oral cancer in a broad sense refers to malignant tumors that occur in the oral cavity. It includes tongue cancer, gum cancer, palate cancer, central jaw cancer, floor of mouth cancer, oropharyngeal cancer, lip cancer, salivary cancer and maxillary sinus cancer, as well as cancers occurring in the skin and mucous membrane of the face. Among them, tongue cancer is the most common.
II. Incidence of oral cancer
In Southeast Asia, the incidence and mortality rate of oral cancer are high, and in Taiwan oral cancer is the third most common malignant tumor in the whole body. In the United States and some other countries in the world, the incidence rate of oral cancer has a trend of increasing year by year. However, the incidence rate of tongue cancer has been increasing rapidly in recent years, and it has nearly accounted for half of all oral cancers; secondly, there is a trend of younger age of oral cancer, and it is not uncommon for young patients aged 20-30.
Oral cancer tends to occur in men, but the number of female patients has been increasing year by year in recent years. Oral cancer can occur at any age, with 40-60 years old as the peak incidence. Tongue cancer is the most common in China, and gum cancer is the second most common.
III. Who is prone to oral cancer
As we all know, the external carcinogenic factors of cancer include physical, chemical and biological factors, which work together with the intrinsic factors such as immunity, genetics and metabolism to transform normal cells into malignant cells and cancer occurs.
1.Tobacco and alcohol
The main carcinogenic factor in tobacco is the chemical benzopyrene, and long-term smokers are much more likely to develop cancer than non-smokers; smoking pipes, cigars or chewing tobacco mainly lead to oral cancer, and cigarette butts touching the lip area are prone to lip cancer, which is related to long-term burns. Alcohol increases the risk of oral cancer due to its toxicity to normal cells and impairs the inhibitory immunity of the liver, and its incidence can increase with the increase of alcohol consumption. The risk of oral cancer is higher for those who are also addicted to tobacco and alcohol, which is 2-3 times higher than those who are addicted to tobacco or alcohol alone. It is generally believed that those who smoke more than 1 pack/day or drink more than 25 g/day are much more likely to develop oral cancer or oropharyngeal cancer for up to 10 years than non-smokers or drinkers.
2.Chronic irritation and injury
If there are sharp tooth tips, residual roots, residual crowns, crests and bad restorations in the oral cavity, there is a possibility of cancer in the corresponding parts after long-term chronic stimulation, especially in tongue cancer and buccal cancer. Statistics show that 1/5 of oral cancer patients have sharp irritation factors at the cancerous site. In addition, the long-term chronic inflammatory stimulation of poor oral hygiene may also become a cancer-promoting factor.
3.Ultraviolet and ionizing radiation
Outdoor workers, who are exposed to direct sunlight for a long time, have higher incidence of lip cancer and skin cancer. Ionizing radiation can cause changes in DNA of genetic material, activate tumor genes and lead to cancer, and both gamma rays and x-rays have carcinogenic effects. Due to the widespread use of radiation therapy for nasopharyngeal cancer, the risk of the second primary cancer in the oral and maxillofacial areas of the radiation zone has increased.
4.Viral factors: such as nasopharyngeal carcinoma is related to EB virus, squamous carcinoma is related to human papilloma (HPV) virus, etc.
5.Intrinsic factors: including gene mutation, genetic factors, immune status, endocrine factors and neuropsychiatric factors.
6.Nutritional factors: Vitamin A1 and B2 and deficiencies of iron, zinc and arsenic will increase the body’s sensitivity to carcinogens. In addition, chronic hepatitis, liver cirrhosis and viral infections, which lead to low immunity of the body, have a certain relationship with the occurrence of oral cancer.
Pre-cancerous lesion and pre-cancerous state of oral cancer
Pre-cancerous lesion: It refers to a kind of tissue that has morphological changes and has a greater possibility of developing cancer than the corresponding normal tissues in appearance.
Precancerous state: a general state that significantly increases the risk of cancer development. Both of them should be given full attention because they are both capable of developing cancer, only the incidence and timing are different.
The most common precancerous lesions on the oral and maxillofacial surfaces should include
1.White spots
White spots of oral mucosa is a recognized precancerous disease, which can be manifested as flat white lesions, or wrinkled paper-like, granular, or even ulcerated. It occurs in cheek and lip mucosa. The cancer rate of oral mucosal leukoplakia can be more than 5%.
2.Erythema
Oral mucosal erythema has been regarded as a disease with higher cancer rate than white spots in recent years. Although the incidence of erythema is much lower than that of leukoplakia, its risk is not negligible, and the cancer rate is as high as 80%. The tongue, floor of the mouth and lateral pharynx are considered high risk areas for erythema.
The most common precancerous states of oral and maxillofacial
1. Lichen planus
Flat moss is a common oral mucosal disease, and its cancer rate is about 1-10%, with vesicular type, atrophic type and plaque type being more prone to malignant transformation, and the most common sites are buccal, tongue and floor of mouth mucosa.
2.Submucosal fibrous lesions of oral cavity
Oral submucosal fibrous lesions are thought to be related to betel nut chewing, and 1/3 of them can eventually develop into cancer. The main manifestations are burning pain when eating, dry mouth and atrophy of oral mucosa. It is commonly found in both sides of the buccal mucosa, lips, tongue and other parts.
V. What are the manifestations of early oral cancer?
1.New organisms appear on the oral and maxillofacial surfaces, such as granular, cauliflower-like surface or early ulceration and pain.
2.Unexplained pain and numbness in tongue, cheek and other parts.
3.Unexplained pain, rapid loosening, loss of teeth, etc.
4.The ulcers in the mouth or face do not heal in January.
5.White or red patches and infiltrated hard lumps of oral mucosa that cannot be explained.
VI. How to prevent oral cancer
1.Understand the factors related to the development of oral cancer and recognize the risk of oral cancer.
2. Ensure nutrition and maintain oral hygiene. Pay attention to the balance of nutrition, quit smoking and alcohol, treat root and crown remnants in time, and remove bad stimuli.
3.Actively deal with and treat precancerous diseases.
4. Do not avoid the disease and seek medical treatment as early as possible, and strive to achieve early detection, early diagnosis and early treatment of cancer, and adhere to regular examination.
VII. What to do when oral cancer is found
Those who find oral cancer or suspect oral cancer should seek medical treatment as early as possible and go to higher level hospitals for treatment in time. At present, the five-year survival rate of oral cancer is about 60%, and the early stage of oral cancer exceeds that rate.