Mouth cancer, also referred to as oral cavity or oral cancer, may grow in any part of the mouth that include –
- Floor of the mouth
- Roof of the mouth
- Inside lining of the cheeks
Types of Oral Cancer
The most common type of oral/mouth cancer is squamous cell carcinoma. This specific type of cancer can be found in a number of places in the body that also include under the skin and inside of the mouth. Other not so common types of mouth cancer are –
- Adenocarcinomas: This rare type of mouth cancer grows within the salivary glands.
- Oral Malignant Melanoma: This is also a rare type of mouth cancer that begins in cells known as melanocytes. These melanocytes are responsible for providing the skin its color.
Oral cancer happens when there is something wrong or unusual in the normal cell lifecycle. This abnormal working of the cell lifecycle results in uncontrollable growth and reproduction of these cells.
Symptoms of Oral Cancer
- Dramatic weight loss
- Bumps or lumps, thickenings/swellings, rough spots or eroded areas or crusts on the gums, lips and/or other areas within the mouth
- Ear pain
- Persistent sores on the mouth, face or neck that causes bleedings and that do not heal within two weeks
- A change in the way the dentures or teeth fit together
- Pain, unexplained numbness, loss of feeling in any area of the neck, face or mouth
- Change in voice, hoarseness or chronic sore throat
- Unexplained bleeding in the mouth
- Problem in speaking, moving the tongue or jaw, swallowing or chewing
- The development of velvety red, white or speckled patches inside the mouth
- A feeling that something is there in the back of the throat
Oral cancer symptoms can be similar with other medical conditions and only a specialist can establish a correct diagnosis. The diagnostic procedure involves a certain number of steps which include:
Detailed medical review of past health state
One of the first steps in establishing an oral cancer diagnosis is a detailed and complex medical review of a patient's past health problems and general health state, family medical history, oral cancer risk factors (especially smoking habits, tobacco and alcohol use), and symptoms.
During a physical examination, the doctor examines the lips, oral cavity, pharynx (back of the mouth, face and neck to look for signs of oral cancer. The specialists looks for any possible lump, abnormal or discolored tissue, or sores.
Biopsy, Imaging and Endoscopy
If any suspicious lesion or ulcer is present then Biopsy is performed, which is followed by endoscopic examination and imaging investigations to find out the stage of the disease.
- Biopsy: This is a painless medical procedure that removes a certain amount of tissue for a microscopic examination. This procedure helps the pathologist to establish the nature of the cells and determine whether they are cancerous or not, and the stage of the cancer. In some cases, the doctor might perform a scalpel biopsy. A scalpel is a thin, straight surgical knife used in dissection and surgery. This type of procedure is performed under anesthesia to reduce patient discomfort.
- Endoscopy: This is a minimally invasive, painless diagnostic procedure used to visualize interior surfaces of certain organs and cavities. During this procedure, a flexible tube, called an endoscope, is inserted into the body in order to provide a clear image of the targeted area. This procedure is used to investigate tissues within the pharynx area which cannot be visualized during a normal mouth examination.
- Computed Tomography (CT): This imaging test is similar to an x-ray test, and creates a detailed, cross-sectional image of the body. This test can identify abnormal tissues and organs. A CT scan is usually performed in two steps for a better diagnosis outcome:
- First, the targeted area is scanned without a contrast agent.
- Second, the targeted area is scanned after a contrast is administrated.
For patients who suffer from oral cancer, this technique is used to localize metastases.
- Magnetic resonance imaging (MRI): An MRI is an advanced technique that uses radio waves and strong magnets to reveal a complete image of a targeted area of the body. The energy from the radio waves is absorbed by the tissues and then released into a pattern that allows the cancer to be detected and diagnosed. This technique is also used to establish whether or not the cancer has spread, and to visualize its location within the body.
- Ultrasonography: Ultrasound imaging is a medical technique that uses high-frequency sound waves to create an interior image of the body on a special computer screen. This image is formed from the echoes of the sound waves on the surface of the organs. Abnormal tissue masses and organs reflect sound waves differently. This test involves a device called transducer, that is placed on the upper part of the abdomen, and a computer that translates this sound into an image. Ultrasound imaging is a safe, noninvasive and fast test that can detect tumors.
The treatment plan for oral cancer varies from patient to patient and is established according to the following five main factors:
- the patient's age, general health and past medical history,
- the cancer type, size, and location,
- the treatment tolerance,
- the risk for hidden disease
- the need to save certain functions.
A better treatment outcome is achieved in patients diagnosed with oral cancer at an early stages.
The main treatment approach in patients with oral cancer are: surgery and radiotherapy with or without Chemotherapy.
Surgery is a procedure aimed to completely remove the tumor tissue together with adjacent healthy tissue in order to prevent relapse of cancer.
THE COMMONLY PERFORMED SURGERIES FOR ORAL CANCER ARE :
Conservative Resections for oral cavity (mouth) Cancer
Conservative resections are done for early cancers of the oral cavity. Main objective is to preserve organs and attain good quality of life for the patient For early tongue cancers only wide excision with reconstruction can be done. For lesions of buccal mucosa (Inner lining of cheek) only resection and preservation of part of mandible (marginal mandibulectomy) can be done. This can be achieved with good results using CO2 laser for surgical Resection. For cancers of upper gum only removal of part of maxillary bone can be done with prosthodontic rehabilitation.
These extensive surgeries are done for locally advanced tumours of oral cavity (mouth) which are caused by tobacco chewing. This involve removal of part of jaw / whole jaw with adjoining buccal mucosa (Inner lining of cheek) with or without removal of skin of cheek. Removal depends on adequate margin of resection.
For cancer of tongue, removal of tongue is done with or without removal of jaw and along with this neck dissection (removal of lymph glands in neck) is done. The gap appearing after the resection is repaired by plastic surgery (local / regional / free flaps). After that patient is rehabilitated by physiotherapist, prosthodontic surgeon, speech and swallowing therapist.
For cancers of cheek bone (maxilla), radical maxillectomy is done, which involves removal of cheek bone (maxilla) with or without preservation of eye depending on involvement of eye or not. If, cheek skin is involved, that is also removed. These tumours may extend to skull base i.e. near the brain, Resection involves removal of the tumour with preservation of vital nerves, which is technically demanding and involves team of experienced Head And Neck Cancer Surgeons. Neuro Surgeons, Plastic and Reconstructive Surgeons to achieve good cancer control and good functional and cosmetic outcome.
Mandible Arch and Floor of the Mouth Resections
These challenging surgeries for advanced loco-regional tumours of the jaw, involve removing the entire tumour including jaw, neck dissection for removal of lymph nodes, removing fibula (leg bone) of the patient and reconstructing the jaw with fibula. This is done to ensure that patient's original facial appearance is maintained and functions of chewing, swallowing and speech are preserved. In this fibular reconstructed Jaw, teeth can be put at later date, so that patient can chew.
Free Flap Reconstructions
Free Flap Reconstruction is a novel plastic reconstruction technique. After cancer resection (removal), large gaps appear in the resected part of the body, which have to be reconstructed by using skin / muscle / bone of the patient. Before the surgery, the part of the body of the patient is chosen as a donor area, ensuring that it aptly matches the area being resected. After taking the graft from the donor area, it is harvested and used for replacing the gap caused by resection. Bone is replaced by a bone from area, where it has minimal function.
This also involves anastomoses (rejoining) of very small blood vessels to restore blood supply and joining of nerves to restore sensory and motor functions of the body. High magnification microscope and very fine sutures (thinner than hair) are used for anastomoses. This procedure is very technically demanding and takes 4 - 10 hours
CO2 Laser surgeries for organ and function preservation
For early vocal cord and laryngeal cancers (voice box cancer) treatment of choice is laser resection of the vocal cord with minimal thermal damage. This is achieved with endoscopic CO2 laser resection. There is no external cut, the neck surgery is done from inside the oral cavity. The advantage of this procedure is that "patient can be discharged the next day and can resume work within few days". This procedure has got minimal side effects with good voice preservation. If CO2 laser surgery is not possible, voice conserving open surgeries are performed, Preserving the voice of a person.
Total Laryngectomies with Voice Rehabilitation
There is hope for patients with advanced cancer of the Larynx (Voice box). Treatment of choice is Total Laryngectomy, a procedure by which the voice box is totally removed. To restore the speech and communication, patients are trained on voice prosthesis or Electro larynx.
OUTCOME OF SURGERY
When performed in early stages, the surgery is small with less post-surgery scars or disfiguration. Patients can eat speak and have normal facial appearance. When performed in advanced stages, the surgery is complex, a substantial amount of tissue needs to be removed, and in most cases requires future reconstruction work.
The side effects are also influenced by the complexity of the surgery and the tumor size. The most common post-surgery side effects include:
- Swelling (the tissue around the operated area can swell for couple of weeks).
- Feeling tired
When the tumor is too big and the procedure involves removing surrounding tissues or organs (such as palate, tongue, or jaw), the patient can experience the following side effects:
- Chewing, swallowing, or talking difficulties
RADIATION THERAPY OR RADIOTHERAPY
Radiation therapy uses high-energy rays or particles to destroy cancerous cells at the local site. The purpose of this treatment is to destroy cancerous tissues preserving the healthy tissue. Radiation therapy is used :-
- As a curative treatment in patients who cannot be operated with small tumors,
- As an adjuvant treatment - in addition to surgery (to enhance the results of the surgery by destroying possible cancerous cells that could have been left behind, and reducing the risk of cancer relapse),
There are two types of radiation therapy performed in patients with oral cancer:
- External beam radiation: This form of radiation therapy uses a device called a linear accelerator that generates an external beam that is concentrated on the tumor area and breaks it up into smaller pieces. Sessions last a few minutes and are administered every day for several weeks.
- Internal radiation (Brachytherapy): The radiation is administrated from radioactive materials (such as seeds, needles, thin tubes) inserted into the tumor. When this time of treatment is administrated, the patient has to stay in the hospital.
In some cases, a patient can receive both types of radiation therapy for a better treatment outcome.
Radiation therapy side effects depend mainly on the radiation dosage and the targeted area. The most common side effects displayed by oral cancer patients that undergo radiation therapy are:
- Dry mouth.
- Eating, swallowing, and talking difficulties.
- Mild to major tooth decay (this side effect can be diminished with a correct and good mouth care, keeping the teeth and gums healthy).
- Sore throat or mouth (painful sores and inflammations).
- Sore or bleeding gums.
- Mouth infections (radiation therapy can damage the mouth lining causing infection).
- Delayed healing (radiation therapy can slow down the healing process for the mouth tissue).
- Jaw stiffness (radiation therapy can affect the chewing muscle which leads to difficulties in opening the mouth).
- Denture problems (radiation therapy might cause the denture to not fit anymore).
- Taste and smell changes (during radiation therapy the food might taste and smell different).
- Voice quality changes (the voice might become weak especially at the end of the day).
- Larynx swelling (this also cause the voice to change and the patient can feel a lump in their neck).
- Thyroid changes (radiation therapy might affect the normal function of the thyroid, decreasing the amount of hormones normally produce by this gland. These can cause the patient to gain weight, to feel tired, to have cold sensations, and dry skin and hair.
- Dry, red and extremely sensitive skin in the area exposed to radiation.
Most of these side effects can be controlled and diminished with medication and are reversible i.e. they will disappear after the radiation is stopped.
This is a systemic type of treatment (affects cells throughout the entire body) that uses drugs either to stop the abnormal growth and dividing process of the cancerous cells, or to kill them. This treatment also has the ability to interfere with the cancerous cells' replication.
Chemotherapy can be administrated in combination with surgery and radiation therapy for a better treatment outcome. The chemotherapy drugs can be given intravenous or as pills.
Chemotherapy side effects include:
- Mouth bleeding and deep pain (that is felt like a toothache).
- Dry mouth
- Gums pain
- Taste changes
- Mouth infections
- Temporary hair loss
- Nausea with or without vomiting
- Loss of appetite
- General vulnerability to infection
- Easy bleeding and bruising
These side effects are temporary, vary from patient to patient according to the drugs and the body reaction to these drugs. Some side effects can be controlled with medication to increase the patient's comfort during the treatment. All these side effects disappear after chemotherapy is stopped.