Oral ( mouth ) cancer

Facts about oral cavity(mouth) cancer

Q 1 what is oral cavity (mouth)cancer?

Oral cancer develops in oral cavity (mouth). The oral cavity includes the

  • Lips
  • Inside lining of the lips and cheeks (buccal mucosa)
  • Teeth and gums
  • Front two-thirds of the tongue
  • Floor of the mouth below the tongue
  • Bony roof of the mouth (hard palate)
  • The area behind the wisdom teeth (called the retromolar trigone)


Q 2 what are causes of oral cavity (mouth) cancer?

  • Tobacco use of any kind, including cigarettes, cigars, pipes, chewing tobacco and snuff
  • Betal nut (Supari) chewing without tobacco
  • Heavy alcohol use
  • Excessive sun exposure to your lips
  • A sexually transmitted virus called human papillomavirus (HPV)

Q 3 what are the types of oral cavity cancer?

  • Squamous cell carcinoma is the most common type
  • Adenoid cystic carcinoma
  • Mucoepidermoid carcinoma
  • Adenocarcinoma

There are many other masses or swellings in the oral cavity that are not cancerous (malignant). These are called benign (non-cancerous) swellings. Benign swellings or masses are not life threatening, but they may cause loss of soft tissue and/ or bone. Examples include Cysts of the Jaw,benign Odontogenic tumors, hamartomasand fibrous dysplasia.

Q 4 What are the pre-cancerous conditions of oral cavity?

Pre-cancerous condition means conditions or lesions have abnormal cells which are associated with an increased risk of developing into cancer. They are not true cancers.

Three most common pre-cancerous lesions/conditions are:

Ø  Leukoplakia – white or gray patch

Ø  Erythroplakia – flat or slightly raised, red area

  • Oral submucosal fibrosis – whitish mucosa lacking elasticity

Q 5 what are the symptoms of oral cavity cancer?

  • A lip or mouth ulcer that doesn’t heal even after 15 days of medical treatment.
  • A white or reddish patch on the inside of your mouth
  • Loose teeth
  • A growth or lump inside your mouth
  • Mouth pain
  • Ear pain
  • Difficult or painful swallowing
  • Neck swelling

A word of caution

All of these symptoms can also be caused by conditions that are not cancer. Kindly consult your doctor first.

Q 6 How is oral cavity cancer diagnosed?

  • The initial assessment include thorough history and physical examination including careful assessment of the nasal cavity and oral cavity with visual examination and/or palpation.
  • Biopsy: If there is any suspicious area or mass visible then doctor may remove a small tissue sample (biopsy)so it can be checked for cancerous cells.

A word of caution

There is common myth that taking biopsy leads to spread of cancer cells in body. This is not true. Taking biopsy does not lead to spread of cancer cells in body.

Biopsy confirms that it is a cancer and not infection and also helps in knowing the type of cancer so that further treatment can be planned accordingly. 

  • Sometimes an examination under anesthesia is performed to characterize the extent of the tumor, to look for synchronous second primary tumors, and to take biopsies for a tissue diagnosis.


If the results of the biopsy confirms the oral cancer, then doctor may advise to have additional tests to assess how widespread the cancer is. These tests may include:

  • Blood tests– To assess the state of liver, kidneys and bone marrow
  • CT/MRI scan– To find out local spread of disease
  • Chest X-ray– To check if the cancer has spread to the lungs or not
  • Bone scan – To check if cancer has spread to bone or not
  • Sometimes a PET scan– To know distant spread of disease

Q 7 What is oral cavity cancer staging?

Staging is a measurement of how far the cancer has spread.

After all the tests have been completed and the results are known, it should be possible to predict what stage the cancer is. The higher the stage, the further the cancer has spread.

  • Stage 1 oral cancer: Cancer is 2 cm in size or smaller, and no cancer cells are present in nearby structures, such as lymph nodes
  • Stage 2 oral cancer: The tumour is larger than 2 cm but no more than 4 cm.
  • Stage 3 oral cancer: The tumour is larger than 4 cm or the cancer has spread to one lymph node in the neck on the same side as the tumour and the lymph node is 3 cm or smaller
  • Stage 4 oral cancer: There are three categories in this stage:

Stage 4A

Cancerof any size and has grown into any of the following:

  • Bone in the palate or lower jaw
  • Nerve in the lower jaw called the inferior alveolar nerve
  • Floor of the mouth
  • Skin of the face

The cancer may also have spread to 1 or more lymph nodes in the neck, and they are 6 cm or smaller.

Stage 4B

The tumour has grown into the soft tissues of the cheek such as muscles, nerves or blood vessels, or into the base of the skull, or the tumour is wrapped around the internal carotid artery of the neck.


The cancer has spread to lymph nodes in the neck and one is larger than 6 cm or the cancer in a lymph node has grown into the surrounding tissue.

Stage 4C

The cancer has spread to other parts of the body (called distant metastasis), such as to the lungs, liver or bone. This is also called metastatic oral cancer.

A word of caution

Above staging is simplified version for your basic understanding. Reader is advised to follow TNM staging system developed by American Joint Committee on Cancer (AJCC) in which

  • T stands for the size and location of primary tumor
  • N stands for nodes. It tells whether the cancer has spread to the nearby lymph nodes
  • M stands for metastasis. It tells whether the cancer has spread to distant parts of the body

Q 8 How oral cavity cancer is treated? 

Oral cavity cancer is curable if diagnosed at an early stage. Surgery and sometimes radiation therapyare the only curative options.

When deciding treatment options for a particular patient, doctor will consider following factors and will decide individual treatment plan:

  • The size of the cancer
  • The stage of the cancer
  • The location of the cancer
  • Your overall health and ability to recover from surgery, radiation therapy or chemotherapy
  • How a treatment will affect appearance and function (such as your speech and ability to swallow and chew)
  • Your personal preferences

Following are the general guidelines but treatment may vary from patient to patient:

  • Early stage disease Stage 1, 2 & 3
  • Surgery followed by radiation therapy and/or chemotherapy. Decision regarding radiation and chemo therapy depends on final pathology report after operation and general condition of patient.
  • Locally advanced disease Stage 4A & stage 4B

Two options exist.

  • Surgery followed by radiation therapy +/- chemotherapy
  • 2 or 3 cycles of chemotherapy followed by surgery and radiotherapy

Decision for above options depends upon local extension of cancer and general condition of the patient.

  • Advanced disease Stage 4C
  • Chemotherapy– Given to slow cancer progression and relieve symptoms.
  • Radiotherapy– to relieve symptoms and improve the quality of life.

V Targeted drug therapy


Surgery includes remove the cancer with surrounding healthy tissue and also to remove cancer that has spread to the neck (neck dissection).

Extent of surgery may vary from wide local excision to hemi or total glossectomy (removal of tongue), mandibulectomy (removal of lower jaw bone), maxillectomy (removal of upper jaw bone), removal of teeth etc.


After surgery, defects made are either closed primarily or with help of plastic surgery.

Many oral cancer surgery patients are often concerned about disfigurement; but recent advances in reconstructive surgery help patients restore their appearance, sometimes with little or no sign of change.


Following the treatment of cancer in the oral cavity, several important functions of the oral cavity may be severely affected. These include the lubrication of the mouth and throat, swallowing difficulties, speech and movement in areas where surgery has been done.

You may need help from specialists in the rehabilitation of the functions such as speech therapists, swallow therapists, physical therapists and occupational therapists.