Oral, Mouth or Tongue Cancer

The Function of the Oral Cavity and Complications Associated with Oral Cancer

The oral cavity, comprising the lips, tongue, cheeks, gums, hard palate, soft palate, floor of the mouth, and oropharynx, plays a vital role in speaking, chewing, swallowing, and the initial stages of digestion. It is also essential for sensory perception, such as taste and temperature detection. When this region is compromised by disease, particularly cancer, it can disrupt critical functions such as speech, nutrition intake, immune defence, and social interaction. Oral cancer can cause tissue destruction, disfigurement, pain, and, if left untreated, life-threatening metastasis or airway obstruction.

Oral cancer originates in the tissues of the mouth or oropharynx and is considered one of the most common cancers worldwide, especially in populations with high tobacco or alcohol use. It typically starts with genetic mutations in the epithelial cells lining the oral cavity, which then proliferate abnormally. While early-stage oral cancer is often treatable, it is frequently diagnosed late due to symptom overlap with benign oral conditions. Raising awareness, reducing exposure to risk factors, and promoting early screening are key to improving outcomes and survival rates globally.

Categories Associated With Primary And Secondary Oral Tumours

Oral cancers are generally classified under two main types:

Primary Oral Cancer: This begins directly in the oral cavity tissues. The most prevalent type is Squamous Cell Carcinoma (SCC), accounting for over 90% of oral malignancies. Other types include Verrucous Carcinoma, Mucoepidermoid Carcinoma, Adenoid Cystic Carcinoma, and rare salivary gland tumours.

Secondary (Metastatic) Oral Cancer: This form of cancer arises when malignancies from other body regions, such as the lungs, breast, kidneys, or prostate, metastasise to the oral cavity. Though rare, metastases to the jawbone or oral soft tissues may indicate advanced systemic disease.

Major risk factors and causes include:

  • Use of tobacco products (smoking and smokeless)
  • Excessive alcohol consumption
  • Human Papillomavirus (HPV) infection, particularly HPV-16
  • Poor oral hygiene and chronic irritation
  • Prolonged sun exposure (for lip cancer)
  • Nutritional deficiencies and immunosuppression

Signs And Symptoms of Oral Cancer

Oral cancer often presents subtly at first and is frequently mistaken for less serious oral lesions or infections. Common symptoms include:

  • Persistent mouth sores or ulcers that do not heal
  • Red or white patches on the tongue, gums, or lining of the mouth
  • Swelling, lumps, or thickening in the cheek or jaw
  • Difficulty or pain when chewing, swallowing, or speaking
  • Chronic sore throat or hoarseness
  • Numbness of the tongue or oral cavity
  • Unexplained weight loss
  • Loosening of teeth or pain in the jaw
  • Ear pain without ear infection

The subtlety of early symptoms and their resemblance to non-cancerous conditions often lead to delayed diagnoses.

Diagnosis of Oral Cancer

Diagnostic procedures for oral cancer include a combination of clinical evaluations, imaging, and histopathological confirmation:

Clinical Examination:

Visual and tactile examination of the oral cavity and neck by a healthcare provider to check for abnormalities.

Imaging Studies:

  • CT scan and MRI of the head and neck for local and regional spread
  • PET scan to assess for metastasis
  • X-ray of the jaw and chest if bone or lung involvement is suspected

Tissue Biopsy:

Essential for confirming diagnosis. A small sample of suspicious tissue is removed and examined microscopically to determine cancer type and grade.

Endoscopy:

An internal camera may be used to assess the throat and adjacent structures for tumour extension.

Staging:

Determining cancer stage involves assessing the size of the tumour (T), lymph node involvement (N), and metastasis (M). This guides prognosis and treatment planning.

Best Treatment for Oral Cancer

Treatment is personalised based on cancer type, size, location, stage, and patient condition. The primary treatment options fall into two categories:

A. Traditional Treatments

B. Advanced and Alternative Treatments

C. Traditional Treatment for Oral Cancer

1. Surgical Procedures

  • Wide Local Excision: Surgical removal of the tumour with surrounding healthy tissue to ensure clear margins.
  • Neck Dissection: Involves the removal of lymph nodes if cancer has spread.
  • Reconstructive Surgery: May be required after tumour removal to restore appearance and function using skin grafts or flap surgery.

2. External Beam Radiation Therapy

Radiation is used to target and destroy cancer cells, particularly in inoperable tumours or post-surgical margins. While effective, it can lead to complications like dry mouth, difficulty swallowing, and mucositis.

3. Systemic Chemotherapy

Commonly used drugs include cisplatin, 5-fluorouracil, and carboplatin. Chemotherapy is used in advanced cases or conjunction with radiation. Side effects may include nausea, immune suppression, and oral ulcers.

B. Advanced Treatments for Oral Cancer

Newer approaches offer improved precision and reduced side effects:

1. Microinvasive Therapies and Surgeries

  • Cryosurgical Ablation:
  • Cryosurgical Ablation (also known as Cryosurgery or Cryo-ablation) is possibly the most promising among so many clinically used ablation treatments. It is carried out by hardening the excrescence kerchief with extremely low temperature.

2. Targeted Therapies

I. Microvascular Interventional Chemo

While less common in oral cancers than liver or pancreas, selective intra-arterial chemotherapy is being explored in head and neck malignancies. It involves direct infusion into blood vessels feeding the tumour.

II. Targeted Drug Therapy

Medications like cetuximab (EGFR inhibitor) or pembrolizumab (PD-1 checkpoint inhibitor) are now used in some oral cancer patients. These therapies block signals that cancer cells use to grow and evade immune detection, with reduced side effects compared to standard chemo.

3. Targeted Radiation Therapy (Brachytherapy)

In early-stage oral cancers, radioactive seeds (Iodine-125 or Palladium-103) are placed near or within the tumour. This allows for high radiation doses at the tumour site while preserving healthy tissue. Especially effective in tongue or lip cancers.

4. Stem Cell Therapies and Immunotherapies for Oral Cancer

CAR-T therapy and immune checkpoint inhibitors (e.g., anti-PD-1/PD-L1 drugs) are promising options, especially for recurrent or metastatic oral cancers. These therapies activate the body’s immune cells to attack cancer without harming normal cells, often combined with surgery or radiation for optimal effect.

Prevention and Lifestyle Management

Prevention plays a crucial role in reducing oral cancer risk:

  • Complete cessation of tobacco and smokeless tobacco use
  • Limiting alcohol intake
  • HPV vaccination for the prevention of oropharyngeal cancers
  • Good oral hygiene and regular dental check-ups
  • A balanced diet rich in fruits, vegetables, and antioxidants
  • Protection from prolonged sun exposure for the lips
  • Routine screening for high-risk individuals (tobacco/alcohol users, prior cancer history)

Early detection during routine dental or medical exams significantly improves survival.

Prognosis and Survival Rates

Prognosis depends largely on the stage of cancer at diagnosis. Early-stage oral cancers treated with surgery and/or radiation can have 5-year survival rates exceeding 75%. However, for advanced-stage cancers, the survival rate drops to approximately 30%–40%. Tumours in hard-to-reach locations or those with distant metastasis have poorer outcomes. Early diagnosis and the use of combination therapies are crucial for improving survival rates.

Conclusion

Oral cancer remains a serious public health challenge due to its multifactorial causes, delayed diagnoses, and high risk of recurrence. Nevertheless, improved awareness, routine screenings, and a combination of traditional and modern therapies—including immunotherapy, targeted radiation, and minimally invasive surgery—offer new hope. Strengthening early detection, lifestyle interventions, and access to care remains essential to reducing the burden of this highly preventable cancer.