It may take several decades of smoking, for instance, to precipitate the development of cancer. Having said that, tobacco use in all its forms is number one on the list of risk factors for true oral cavity cancers in individuals over This percentage is now changing, and exact percentages are yet to be definitively determined and published, as new data related to a decrease in tobacco use are changing the dynamic very rapidly.
When you combine tobacco with heavy use of alcohol, your risk is significantly increased, as the two-act synergistically. Those who both smoke and drink, have a 15 times greater risk of developing oral cancer than others. It does not appear that the HPV16 viral cause needs to act synergistically with tobacco or alcohol, and HPV16 represents a completely unique and independent disease process in the oropharynx.
Tobacco and alcohol are essentially chemical factors, but they can also be considered lifestyle factors since we have some control over them. Besides these, there are physical factors such as exposure to ultraviolet radiation. This is a causative agent in cancers of the lip, as well as other skin cancers. Cancer of the lip is one oral cancer whose numbers have declined in the last few decades. This is likely due to the increased awareness of the damaging effects of prolonged exposure to sunlight, and the use of sunscreens for protection.
Another physical factor is exposure to x-rays. Radiographs were regularly taken during examinations, and at the dental office are safe, but remember that radiation exposure is accumulative over a lifetime. It has been implicated in several head and neck cancers. Biological factors include viruses and fungi, which have been found in association with oral cancers.
The human papillomavirus, particularly HPV16, has been definitively implicated in oropharyngeal cancers Oropharynx, the base of the tongue, tonsillar pillars, and crypt, as well as the tonsils themselves.
HPV is a common, sexually transmitted virus, which infects about 40 million Americans today. There are about strains of HPV, the majority of which are thought to be harmless. So we wish to be clear. Infection with even a high-risk HPV virus does not mean that you will develop oral cancer. It is likely that the changes in sexual behaviors of young adults over the last few decades, and which are continuing today, are increasing the spread of HPV, and the oncogenic versions of it.
There are other minor risk factors that have been associated with oral cancers but have not yet been definitively shown to participate in their development.
These include lichen planus, an inflammatory disease of the oral soft tissues, and genetic predispositions. More about HPV and oral cancer. More about viruses and all cancers. There are studies which indicate a diet low in fruits and vegetables could be a risk factor, and that conversely, one high in these foods may have a protective value against many types of cancer.
More about nutrition and cancer Clearly cancer is a very complex group of diseases, and diet alone should not be considered a stand-alone causative factor for initiation of the cascade of cellular events that change a cell from normal to malignant. One of the real dangers of this cancer is that in its early stages, it can go unnoticed. It can be painless, and little in the way of physical changes may be obvious. The good news is, that your Physician or Dentist can in many cases, see or feel the precursor tissue changes, or actual cancer while it is still very small, or in its earliest stages.
More about the stages of cancer It may appear as a white or red patch of tissue in the mouth, or a small indurated ulcer that looks like a common canker sore. Because there are so many benign tissue changes that occur normally in your mouth, and some things as simple as a bite on the inside of your cheek may mimic the look of a dangerous tissue change, it is important to have any sore or discolored area of your mouth, which does not heal within 14 days, looked at by a professional.
Unilateral persistent earache can also be a warning sign. Thus, assessment of the mandible is essential for appropriate surgical planning and treatment.
In some circumstances, the floor of the mouth tumors can be removed via transoral approach, regularly combined with marginal or segmental mandibulectomy. The local control rate is declined to own to the mandibular invasion. That said, this resection is based on an assessment of the invasive cortex and bone marrow before surgery.
The current indications for marginal mandibulectomy are: 1 for obtaining satisfactory three-dimensional margins around the primary tumor, 2 when the primary tumor approximates the mandible and 3 for minimal erosion of the alveolar process of the mandible Figure 6. A Cancer of lower gingiva.
B Marginal mandibulectomy for cancer of lower gingiva. The current indications for segmental mandibulectomy include: 1 gross invasion by oral cancer; 2 proximity of oral cancer to the mandible in a previously irradiated patient; 3 invasion of the inferior alveolar nerve or canal by tumor [ 12 , 25 , 26 ]. Management of the neck is a key component of oral cavity cancer treatment. Sixty percentage of patients with metastatic cervical lymph nodes cN0 in the early stage of oral cancer cannot be clinically detected.
The risk of neck lymph node metastasis is associated with several factors such as tumor size, histologic grade, depth of invasion, perineural invasion and vascular invasion [ 27 , 28 ]. Cervical lymph node metastasis is the most essentially prognostic aspect of oral cancer. The SND is not indicated in the circumstances of the hard palate and maxillary gland tumors owing to their less possibility to have lymph node metastasis.
Sentinel node biopsy may be an alternative to SND in patients with early stage cT1,2 N0 squamous cell carcinoma. Notably, this technique was initially published in by Shoaib and colleagues, then analyzed in several single-center studies and two multi-center clinical trial studies, one in the US and one in Europe [ 31 ]. On the other hand, the procedure is still a big technical challenge and unsustainable success in identifying lymph nodes and metastases which highly dependent on the experience and competence of surgeons.
That is to say, this technique could only be performed in some of the intensive centers with proficient skills. In some patients with lymph node metastasis on clinical examination or diagnostic imaging, therapeutic comprehensive neck dissection is indicated, including cervical lymph node group I to V group. The conservation or destruction of other structures such as the spinal accessory nerve, sternocleidomastoid muscle, or internal jugular is vein reliant on the location as well as the metastatic characteristics.
The most common type of comprehensive neck dissection is the modified radical neck dissection, MRND Type 1.
Radical neck dissection is rarely performed unless there is a direct extranodal spread of the lymph nodes to evade into the corresponding organs. Likewise, in patients without clinical lymph node metastases, the underlying risk of lymph node metastasis is mainly in the group I-III, rarely in the groups IV and V. Then again, patients are appropriately chosen to optimize postoperative radiation therapy. Reconstructive surgery plays an important role in treatment for oral cavity cancer.
The defects after surgery can cause significant issues in airway management, mastication, speech and cosmesis. The aim of reconstructive surgery is to restore presurgical function and cosmesis. Primary reconstruction, rather than a secondary surgery, has become the first choice of treatment for most cases with oral cancer.
Primary closure or the use of skin graft can indicate for defects after oral surgery of early stage tumors. Contrarily, with large and complex defects after the oral tumor resection, plastic surgery needs the participation of an expert reconstructive surgeon. Microvascular free flap surgery is the prevailingly preferential technique.
For instance, application of the free radial forearm flap into patients with soft tissue defects of tongue, the floor of mouth or retromolar trigone apparently performs an excellent result. In addition to the purpose of covering the soft tissue, the free flap is also a reliable method for recovering the bone defects, such as the fibula free flap used as post-surgical reconstruction after segmental mandibulectomy.
Other combined microvascular flanges could be considered as radial forearm osteocutaneous flap, iliac crest and scapula free flaps. The potency to recover major defects after surgery has contributed to improving the oncologic outcomes in patients with locally advanced stage due to increased ability to complete resection [ 35 ].
Postoperative adjuvant therapy is indicated to patients with high risks of the local, regional recurrence, including pT3,4 primary tumors, pN2,3 lymph node metastases, level IV or V lymph node metastases, positive margins, lymphovascular invasion, perineural invasion and extracapsular spread. Indeed, external beam radiation is the traditional adjuvant treatment, with doses of 60—70 Gy often providing positive control.
Two clinical trials have shown that adjuvant radiotherapy with cisplatin significantly improves the control rates along with survival time compared to the single adjuvant radiation therapy in those who have invasive head and neck cancer with extracapsular spread [ 36 , 37 ]. But for all that concomitant radiotherapy has more severe side effects, so it should be carried out in the large centers with an expert team and appropriate infrastructure.
The clinical stage is the key predictor of survival. Lymph node metastasis is the single most important prognostic factor for oncologic outcome in oral cancer [ 39 ]. Besides, the number and size of positive lymph nodes, the presence of extranodal extension higher histologic grade, the presence of perineural invasion and increasing size have been correlated with worse outcomes [ 40 , 41 , 42 ].
These programs were subsequently evaluated at the next External Advisory Board meeting which took place on November , , at the Hotel Commonwealth located adjacent to the Charles River Campus. The Research office offers pre-submission grant review assistance to all GSDM faculty, residents and students. This service is offered to any member of the GSDM community who intends to apply for extramural funding.
The Research office will solicit the help of established researchers on the Boston University Medical Campus. Their expertise will help ensure that GSDM grant submissions are competitive and of the highest quality.
That means 53, new cases of oral cancer per year. Squamous cell carcinoma : More than 90 percent of cancers that occur in the oral cavity are squamous cell carcinomas. Normally, the throat and mouth are lined with so-called squamous cells, which are flat and look like fish scales on a microscopic level.
Squamous cell carcinoma develops when some squamous cells mutate and become abnormal. Verrucous carcinoma: About 5 percent of all oral cavity tumors are verrucous carcinoma, a type of very slow-growing cancer made up of squamous cells. This type of oral cancer rarely spreads to other parts of the body, but it may invade nearby tissue.
Minor salivary gland carcinomas: This disease includes several types of oral cancer that may develop on the minor salivary glands, which are located throughout the lining of the mouth and throat. These include adenoid cystic carcinoma, mucoepidermoid carcinoma and polymorphous low-grade adenocarcinoma. Lymphoma: Oral cancers that develop in lymph tissue, which is part of the immune system, are known as lymphomas. The tonsils and base of the tongue both contain lymphoid tissue. Benign oral cavity tumors: Several types of non-cancerous tumors and tumor-like conditions may develop in the oral cavity and oropharynx.
Sometimes, these conditions may develop into cancer. For this reason, benign tumors are often surgically removed. The types of benign lesions include:.
Leukoplakia and erythroplakia: These non-cancerous conditions develop when certain types of abnormal cells form in the mouth or throat. When leukoplakia develops, a white area is visible, while erythroplakia is marked by a red area, which may be flat or slightly raised and often bleeds when scraped.
Both conditions may be precancerous, meaning they may develop into various types of cancer. When these conditions occur, a biopsy or other test is performed to determine whether the cells are cancerous.
About 25 percent of leukoplakias are either cancerous when first discovered or become precancerous. Erythroplakia is usually more serious, with about 70 percent of cases deemed to be cancerous, either at the time of diagnosis or later.
Lip cancer, the most common form of oral cancer, affects mostly men. The most common type of lip cancer forms in the squamous cells, which are the thin, flat cells that line the lips and mouth. Lip cancer is diagnosed using tests such as:. Lip cancer symptoms are similar to those of other types of oral cancer.
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