Mouth cancer or Oral cancer

What are the causes of mouth cancer?

Mouth cancer results from mutations (DNA changes) in the concerned cells. These mutations cause cells to divide and grow uncontrollably thereby leading to the formation of a tumor. Though the reason for mutation is not established yet, there are certain factors that predispose cells to these changes.

What are the stages of mouth cancer?

Once the diagnosis is done, the stage of the cancer is determined.

Staging of cancer is done to assess the size and extent of spread. It also helps the oncologist to decide the treatment plan.

Cancer staging is done in two ways: TNM (Tumour, Node, Metastasis) staging and Number staging from I to IV. It was developed by the International Union against Cancer and the American Joint Committee on Cancer (AJCC).

• ‘T’ refers to the size of the primary tumor
• ‘N’ refers to whether the lymph nodes in the neck area have become cancerous
• ‘M’ refers to whether cancer has spread to distant organs in the body (metastasized), such as your lungs, bones, or liver

Stages progress from I to IV ranging from smallest and confined to biggest and widespread to other areas.

Stage 0: In stage 0, oral cancer begins to grow on the surface (protective lining) of the oral cavity.

Stage 1: Cancer has begun to grow deeper into the tissues in the oral cavity. Stage 1 oral cancer is small in size and localized to oral cavity but has not yet spread to lymph nodes or distant sites.

Stage 2: In stage 2, cancer has grown larger (up to 4 cm), but cancer is still localized.

Stage 3: Oral cancer has grown larger than 4 cm. Stage 3 oropharyngeal cancer has grown into the epiglottis (the base of the tongue). There are chances that cancer has spread to the lymph node on the same side of the primary tumor. However, cancer has not spread to the distant sites.

Stage 4: Stage 4 oral cancer may vary greatly in size. In moderately advanced local disease (stage 4A), the nearby bone, skin and sinus may be involved.

• Lip cancers: Cancer may grow into nearby structures such as skin of the chin or nose, jawbone, floor of the mouth, and the inferior alveolar nerve (the nerve to the jawbone).
• Oral cavity cancers: Cancer may spread to bones of the jaw or face, maxillary sinus, and deep muscle of the tongue.
• Oropharyngeal cancer: Cancer may spread to bones of the jaw or face, larynx (voice box), and deep muscle of the tongue.

In stage 4A, the cancer may or may not have spread to the lymph nodes (on the same or opposite side of the tumor). As cancer progresses to stage 4B, the size of cancer becomes larger and grows outside the lymph node(s). Cancer grows further and spreads to nearby structures such as the base of the skull or bones nearby and carotid artery. This is called as a very advanced local disease (stage 4B). Once cancer spreads to nearby soft tissues, lymph nodes and distant organs, it is called as stage 4C oral cancer.

What is the treatment for mouth cancer?

The treatment plan for mouth cancer is determined by location and stage of cancer, overall health of the patient, and personal preference. The treatment modalities may be used individually or in combination.

• Surgery is done for removal of primary cancer and lymph nodes if involved and mouth reconstruction to replace the mouthparts lost during the corrective surgery
• Radiation therapy: Use of high-powered energy beams to destroy cancer cells
• Chemotherapy: Use of drugs to destroy cancer cells
• Radiosurgery: Also known as Stereotactic body radiotherapy, intense radiation is used instead of surgery
• Targeted-drug therapy: Use of drugs that act on cancer cells and selectively destroy only cancer cells
• Biological therapy: Makes use of the body’s immune system to fight cancer cells
• Palliative care: Intended to improve the quality of life of cancer patients who may not be amenable to treatment

Since mouth cancer requires a multidisciplinary management, look for a hospital that has an expert team of oral and maxillofacial surgeons, oncologist, onco-surgeon and radiation oncologist with a trained staff. The hospital should also have infrastructure like diagnostic support, modular OT, ICU and facility for radiation therapy and chemotherapy.

How can one prevent mouth cancer?