Oral, Mouth and Throat Cancer

Mouth cancer can appear as a painless mouth ulcer that does not heal normally. A white or red patch in the mouth can also develop into a cancer. Alcohol increases the risk of mouth cancer, and if tobacco and alcohol are consumed together the risk is even greater. Over-exposure to sunlight can also increase the risk of cancer of the lips. Most cases of mouth cancer are linked to tobacco and alcohol. Cigarette, cigar and pipe smoking are the main forms of tobacco use in many parts of the world. However, the traditional habits in some cultures of chewing tobacco, betel quid, gutkha and paan are particularly dangerous. 

Throat cancer refers to cancerous tumours that develop in your throat (pharynx), larynx or tonsils.  Cancer is a class of diseases in which abnormal cells multiply and divide uncontrollably in the body. These abnormal cells form malignant growths called tumors. Throat cancer refers to cancer of the voice box, the vocal cords, and other parts of the throat, such as the tonsils and the oropharynx. Throat cancer is often grouped into two categories: pharyngeal cancer, which forms in the pharynx and laryngeal cancer, which forms in the larynx.

Cancers that are known collectively as head and neck cancers usually begin in the squamous cells that line the moist, mucosal surfaces inside the head and neck. These squamous cell cancers are often referred to as squamous cell carcinomas of the head and neck. The two most important risk factors for head and neck cancers, especially cancers of the oral cavity, oropharynx, hypopharynx, and larynx. At least 75 percent of head and neck cancers are caused by tobacco and alcohol use. Infection with cancer-causing types of human papillomavirus (HPV), especially HPV-16 is a risk factor for some types of head and neck cancers, particularly oropharyngeal cancers that involve the tonsils or the base of the tongue. 

Most cases of oral cancer are because of cigarette smoking, heavy alcohol use or the use of both tobacco and alcohol consumptions. Using tobacco plus alcohol poses a much greater risk than using either substance alone. HPV Infection with the sexually transmitted human papillomavirus has been linked to a subset of oral cancers.  Cancer of the lip can be caused by sun exposure. A low nutrient diet because of fewer intakes of fruits and vegetables may play a role in oral cancer development. Risk increases with age. Oral cancer most often occurs in people over the age of 40.

The stage of oral cancer is one of the most important factors in evaluating treatment options. A stage 0 oral cancer tumor means the cancer is only growing in the epithelium which is the outermost layer of tissue in the oral cavity. A stage I oral cancer tumor means the primary tumor is 2 cm across or smaller and no cancer cells are present in nearby structures, lymph nodes or distant sites. A stage II oral tumor measures 2–4 cm across and no cancer cells are present in nearby structures, lymph nodes or distant sites. The oral tumor is larger than 4 cm across and no cancer cells are present in nearby structures, lymph nodes or distant sites is stage III. Stage IV is the tumor has invaded deeper areas and/or tissues. It may or may not have spread to lymph nodes and has not spread to distant sites. Recurrent or relapsed disease means that the cancer has returned after treatment. Recurrent disease does not have a TNM classification or a staging system number. TNM system is a commonly accepted method based on three key components Tumor, Node and Metastasis.   

All types of carcinomas are seen in oral cavity, the most common form of OC is squamous cell carcinoma. Use of genetic and proteomic approach in recent years have revealed the molecular pathological picture of Oral Cancer. Genetic alterations define molecular basis of carcinogenesis which includes point mutations, amplifications, rearrangements and deletions. Several oncogenes have also been implicated in oral carcinogenesis. Genomic instability such as loss of hetrozygosity and microsatellite instability are frequently observed in cancer and such instability has been investigated and several reports are available in Oral Cancer.  

The goal of oral cancer screening is to identify mouth cancer early, when there is a greater chance for a cure. The patient will undergo a thorough examination of the head and neck to look for lesions and abnormalities. A mirror exam and/or an indirect laryngoscopy will most likely be done to view areas that are not directly visible on examination. Tests are done to know whether it is a Cancer mimic or not. Salivary diagnostics are also done to test for Oral Cancer. PET scan is another diagnostic tool in which, a form of radioactive sugar is injected into the blood. Because cancer cells use glucose at a higher rate than normal cells, they will absorb more of the radioactive sugar and the radioactivity will to concentrate in the cancer.  

Depending on the stage of Oral Cancer the type of surgery is recommended. Tumor resection is an operation to remove the entire tumor. Some normal tissue surrounding the tumor is also removed to ensure that no cancer cells remain in the body. Mohs micrographic surgery is a tumor removed in very thin slices, with each slice examined under the microscope for the presence of cancer cells. Full or partial mandible (jawbone) resection when a tumor has grown into the jawbone, a mandibular resection or mandibulectomy, may be needed. Glossectomy is type of cancer surgery, which involves removal of the tongue, is used to treat cancers of the tongue. Maxillectomy is the operation removes all or part of the hard palate, the front of the roof of the mouth. Laryngectomy is the surgical oncology procedure involves removing the voice box along with the primary tumor. Neck dissection is the type of oral cancer surgery is used to remove lymph nodes in the neck if cancer has spread to this area. 

Radiation therapy may be the main treatment for oral cavity cancer or it can be used after surgery to destroy small areas of cancer that could not be removed. Chemotherapy is the use of drugs to destroy cancer cells usually by stopping the cancer cells’ ability to grow and divide. Immunotherapy also called biologic therapy is designed to boost the body’s natural defenses to fight cancer. Targeted therapy is a treatment that targets the cancer’s specific genes, proteins or the tissue environment that contributes to cancer growth and survival. Cancer and its treatment often cause side effects. In the process of cancer treatment, it is an important part to take care a person’s adverse effects caused by the anti-cancer therapy with suitable medication. This approach is called palliative or supportive care, and it includes supporting the patient with his or her physical, emotional and social needs. A remission is when cancer cannot be detected in the body and there are no symptoms. This may also be called “no evidence of disease”.

Complications of cancer treatment may vary with the degrees of severity, depending on the individual and the cancer treatment. Chemotherapy often impairs the function of bone marrow, suppressing the formation of white blood cells, red blood corpuscles and platelets. Some cancer treatments are described as stomatotoxic because they have lethal effects on the oral tissues. Infections like Viral, bacterial and fungal results from myelosuppression, xerostomia or damage to the mucosa from chemotherapy & radiotherapy.  There may be a risk of rampant dental decay throughout the life which may begin within 3 months of completing oral cancer treatment, is nothing but either the quality or quantity of saliva persists.   

It is a sort of action to stop cancer from occurrence or arising. Different ways to prevent cancer are changing lifestyle, eating habits, avoiding things known to cause cancer and Taking medication to treat a precancerous condition. Regular health check-ups can also prevent cancer. Even some times Family History or hereditary also plays an important role in preventing the cancer. 

Otorhinolaryngology (Otolaryngology-Head and Neck Surgery) is the area of medicine that deals with disorders conditions of the ear, nose, and throat region, and related areas of the head and neck.

Dentistry is a branch of medicine that is involved in the study, diagnosis, prevention, and treatment of diseases, disorders and conditions of the oral cavity, commonly in the dentition but also the oral mucosa, and of adjacent and related structures and tissues, particularly in the maxillofacial (jaw and facial) area.

Oral Cavity Cancer is associated with high incidence of loco-regional recurrences, which account for the majority of treatment failures post-surgery and radiotherapy. The time-course of relapse manifestation and metastasis are unpredictable. Relapsed OCC represents a major clinical challenge in part due to their aggressive and invasive behaviors. Chemotherapy remains the only option for advanced OCC whenever salvage surgery or re-irradiation is not feasible, but its efficacy is limited as a result of the drug resistance development. Alternatives to use of different permutations of standard cytotoxic drugs or combinations with modulators of drug resistance have led to incremental therapeutic benefits. The introduction of targeted agents and biologics against selective targets that drive cancer progression has opened-up optimism to achieve superior therapeutic activity and overcome drug resistance because, unlike the non-selective cytotoxic, the target can be monitored at molecular levels to identify patients who can benefit from the drug. This review discusses the multifactorial aspects of clinical drug resistance and emerging therapeutic approaches in recurrent OCC, emphasizing recent advances in targeted therapies, immunotherapy, and potential relevance of new concepts such as epithelial-mesenchymal transition and cancer stem cell hypothesis to drug resistance.

Oral biology is that area of knowledge that deals with the structure, development, and function of the oral tissues, their interrelationships and their relation to other organ systems in both health and disease.

Oral & Maxillofacial Surgery specializes in treating many diseases, injuries and defects in the head, neck, face, jaws and the hard and soft tissues of the Oral and Maxillofacial region. It is an internationally recognized surgical specialty. In some countries around the world, including the United States, Canada and Australia, it is a recognized specialty of dentistry  in others, such as the UK and most of Europe, it is recognized as both a specialty of medicine and dentistry and a dual degree in medicine and dentistry is compulsory.

This session is designed to share important information and latest advancements in Oral Cancer Treatment and the issues with Oral Oncology.