Oral Cancer overview
Oral cancer develops between the lips and in the back portion of the tongue. Cancer of the oral cavity is one of the most frequent subtypes of head and neck malignancies, and the most prevalent kind of oral cancer is squamous cell carcinoma (OSCC).
According to Shield et al. 2017, oral cavity cancers (lip, oral tongue, gingiva, floor of mouth, palate, and other parts, including buccal mucosa) account for around 250 000 incident cases globally each year. Furthermore, men had a higher incidence and death rate (2.3 percent and 1.7 percent, respectively) than women (1.2 percent and 0.8 percent, respectively)
Because it affects the efficiency of eating and speech, oral cancer impacts the quality of life of patients.
What Are the Symptoms of Oral Cancer?
Many patients are asymptomatic in the early stages. Therefore, it is relevant to have an early diagnosis to prevent future complications. The oral cancer symptoms most common are:
- A white patch lesion (leukoplakia)
- A red patch lesion (erythroplakia)
- Pain or difficulty swallowing
- a non-healing extraction socket (>6 weeks)
- pigmented lesion (oral melanoma)
- persistent lump or growth in the oral mucosa
- Burning mouth
- Paralysis, numbness, or pain/tenderness in any part of the face, mouth, or neck
Any mucosal lesion that persists for more than two weeks after the removal of suspected local irritants must be biopsied.
The white and red patch lesions can also be harmless, but it is necessary to receive a study to verify their state. Furthermore, it is essential to immediately notify a doctor or dentist of any change or appearance of strange lesions in the mouth or neck.
What factors contribute to the development of oral cancer?
The development of oral cancer is characterized by several genetic disorders. Additionally, it is a complex process of several steps that disturbs cell signaling, growth, survival, motility, the generation of blood vessels, and the control of the cell cycle.
Risk factors for developing oral cancer
Tobacco smoking and alcohol drinking are responsible for around 75% of the lip, oral cavity, and pharyngeal malignancies in developed countries.
While chewing betel quid with or without tobacco, the use of tobacco pipes, the ingestion of nitrosamine-rich foods, and infection are risk factors for lip, oral cavity, and pharyngeal cancers in underdeveloped nations.
Risk factors for oral cancer typically include:
- Heavy use of tobacco
- Betel quid chewing
- Consumption of alcoholic beverages
- Chronic inflammation
- Family history of squamous cell carcinoma
- Prevalence of HPV-associated (mainly HPV type 16)
- Oral mucosal trauma from teeth and prosthetic devices
- Actinic ultraviolet radiation (UV), mainly UV-B.
- Genetic conditions
How Is Oral Cancer Diagnosed?
A dentist or doctor should perform the initial analysis by examining different anatomical locations. If a suspicious lesion is observed or palpated in the oral cavity or nearby, a lesion biopsy should be performed.
A biopsy is a tissue sample obtained from the body to be analyzed more precisely. A biopsy of oral cancer reveals the degree of cellular differentiation and pattern of dissemination.
Additionally, according to the type of lesion and its extension, the specialist will decide the type of study to be carried out. The dentist or doctor may perform one or more tests, such as X-rays, CT scans, PET scans, or MRI scans.
How Is Oral Cancer Treated?
To determine the appropriate treatment for each patient, it is important to initially identify the type, spread, and stage of the carcinoma.
Each patient should have an individual treatment plan developed by a multidisciplinary team. At least one surgeon, medical oncologist, radiotherapist, nursing specialist, pathologist, dietician, speech therapist, and other specialists are part of the team.
Most intraoral carcinomas are treated with surgery and irradiation (referred to as multimodality therapy). Surgery alone is preferable for small tongue carcinomas that may be readily removed, those affecting bone due to the danger of subsequent radionecrosis, and verrucous carcinoma.
The goal is to remove the carcinoma with as broad a margin as possible, ideally one centimeter or more. Reconstructive surgery is typically performed concurrently with excision to produce a better aesthetic and functional result, and it makes use of a variety of donor tissue sources.
Radiotherapy often entails being exposed to X-ray or gamma-ray beams from X-ray sources or radioactive isotopes. Ionizing radiation causes harm to both normal and malignant tissue.
Chemotherapy is the use of chemicals to destroy cancer cells. It works by preventing cancer cells from growing, dividing, and proliferating. For oral cancer, it is most effective when used in conjunction with radiation therapy and delivers a 10% improvement in survival at best.
What Is the Prognosis for Oral Cancer Patients?
Unfortunately, oral cancer has a poor prognosis, with overall 5-year survival rates as low as 40%, while survival rates can surpass 80% if detected in the early stages (I and II). Many patients who are asymptomatic in the early stages may not seek medical treatment until they experience noticeable symptoms such as discomfort, bleeding, or a mass in the mouth or neck if lymphatic dissemination is already present. As a result, 50% of oral cancers are diagnosed at an advanced stage (stage III or IV).
What Can I Do to Prevent Oral Cancer?
- Regularly see your dentist for dental examinations, and inquire about oral cancer screenings.
- Do not use tobacco or inhale drugs
- Limit alcohol consumption.
- Limit sun exposure.
- Eat a healthy diet.
- Regularly examine your mouth for signs or symptoms, and notify your dentist of any changes.
Abati, S., Bramati, C., Bondi, S., Lissoni, A., & Trimarchi, M. (2020). Oral Cancer and Precancer: A Narrative Review on the Relevance of Early Diagnosis. International journal of environmental research and public health, 17(24), 9160. https://www.mdpi.com/1660-4601/17/24/9160
Lousada-Fernandez, F., Rapado-Gonzalez, O., Lopez-Cedrun, J. L., Lopez-Lopez, R., Muinelo-Romay, L., & Suarez-Cunqueiro, M. M. (2018). Liquid Biopsy in Oral Cancer. International journal of molecular sciences, 19(6), 1704. https://www.mdpi.com/1422-0067/19/6/1704
Odell, E. (2002). Cawson’s Essentials of Oral Pathology and Oral Medicine (8th ed., p. 277). Elsevier.
Shield, K.D., Ferlay, J., Jemal, A., Sankaranarayanan, R., Chaturvedi, A.K., Bray, F. and Soerjomataram, I. (2017), The global incidence of lip, oral cavity, and pharyngeal cancers by subsite in 2012. CA: A Cancer Journal for Clinicians, 67: 51-64. https://acsjournals.onlinelibrary.wiley.com/doi/full/10.3322/caac.21384
Rivera C. (2015). Essentials of oral cancer. International journal of clinical and experimental pathology, 8(9), 11884–11894.
Vigneswaran, N., & Williams, M. D. (2014). Epidemiologic trends in head and neck cancer and aids in diagnosis. Oral and maxillofacial surgery clinics of North America, 26(2), 123–141. https://www.sciencedirect.com/science/article/abs/pii/S1042369914000028
Vonk, J., de Wit, J. G., Voskuil, F. J., & Witjes, M. (2021). Improving oral cavity cancer diagnosis and treatment with fluorescence molecular imaging. Oral diseases, 27(1), 21–26. https://onlinelibrary.wiley.com/doi/10.1111/odi.13308
Wong, T., & Wiesenfeld, D. (2018). Oral Cancer.