Head and Neck Cancer

The Function of the Head and Neck Region and Complications Associated with Head and Neck Cancer

The head and neck region encompasses multiple vital anatomical structures, including the oral cavity, pharynx, larynx, nasal cavity, sinuses, salivary glands, and lymph nodes. These structures play crucial roles in breathing, speaking, swallowing, hearing, smelling, and facial expressions. When cancer affects any part of this region, it can impair essential functions such as communication, food intake, and airway maintenance, leading to severe physiological and psychological complications. Head and neck cancers can cause pain, disfigurement, difficulty in speaking and swallowing, and life-threatening airway obstruction or metastasis if untreated.

Head and neck cancer usually begins in the squamous cells lining the moist surfaces of the head and neck; hence, it is often called squamous cell carcinoma. The disease is strongly linked to tobacco use, alcohol abuse, and infection with human papillomavirus (HPV). It is especially aggressive due to its proximity to critical nerves and blood vessels. Although some types can be detected early through visible symptoms, many are diagnosed late, making treatment more complex. Increasing awareness through early screening and risk factor education is essential to reduce morbidity and improve survival rates.

Categories Associated With Primary And Secondary Head and Neck Tumours

Head and neck cancers are typically classified by location and origin:

Primary Head and Neck Cancer: This originates from the tissues of the head and neck. The most common sites include:

  • Oral Cavity
  • Pharynx (nasopharynx, oropharynx, hypopharynx)
  • Larynx (voice box)
  • Nasal Cavity and Paranasal Sinuses
  • Salivary Glands

Squamous Cell Carcinoma (SCC) is the predominant histological type. Other less common types include Adenocarcinoma, Lymphoma, Sarcoma, and Melanoma.

Secondary (Metastatic) Head and Neck Cancer: These tumours arise when cancer from other body sites, such as the lungs, breasts, or gastrointestinal tract, spreads to the lymph nodes or tissues in the head and neck region.

Common causes and risk factors include:

  • Tobacco use (smoking and smokeless forms)
  • Heavy alcohol consumption
  • Human Papillomavirus (HPV), especially HPV-16
  • Epstein-Barr virus (EBV) in nasopharyngeal carcinoma
  • Poor oral hygiene and dental neglect
  • Industrial chemical exposure (e.g., asbestos, wood dust)
  • Genetic predisposition

Signs And Symptoms of Head and Neck Cancer

Symptoms of head and neck cancer vary depending on the site affected, but often include:

  • Persistent sore throat
  • Difficulty or pain while swallowing
  • Hoarseness or voice changes
  • Unexplained weight loss
  • Swelling or lumps in the neck or face
  • Ear pain without infection
  • Chronic nasal congestion or nosebleeds
  • Ulcers or white/red patches in the mouth
  • Numbness or weakness in the face
  • Jaw stiffness or trouble opening the mouth

Early symptoms may mimic minor infections, making early diagnosis a challenge without proper evaluation.

Diagnosis of Head and Neck Cancer

A multidisciplinary approach is used to diagnose head and neck cancers:

Clinical Evaluation:

Detailed history and physical examination of the mouth, throat, nose, neck, and lymph nodes by an ENT specialist.

Imaging Studies:

  • CT scan and MRI for tumour localisation and soft tissue evaluation
  • PET scan to assess metabolic activity and metastasis
  • Ultrasound for lymph node assessment

Endoscopy:

Flexible nasopharyngoscopy or laryngoscopy to directly visualise tumour growth within internal cavities.

Biopsy:

Fine Needle Aspiration (FNA) or incisional biopsy for pathological confirmation and cancer grading.

Staging:

The TNM (Tumour, Node, Metastasis) staging system is used to classify cancer extent and guide treatment strategies.

Best Treatment for Head and Neck Cancer

Treatment is based on cancer type, size, stage, location, and overall health of the patient. Major categories include:

A. Traditional Treatments

B. Advanced and Alternative Treatments

C. Traditional Treatment for Head and Neck Cancer

1. Surgical Procedures

  • Tumour Excision: Removal of the primary tumour with clear margins.
  • Neck Dissection: Removal of lymph nodes in the neck to prevent or manage metastasis.
  • Reconstructive Surgery: Post-tumour removal, reconstructive procedures may restore function and appearance.

2. External Beam Radiation Therapy

Highly focused radiation is used to destroy cancer cells and shrink tumours. Intensity-Modulated Radiation Therapy (IMRT) reduces damage to surrounding healthy tissue. Side effects may include dry mouth, throat pain, and skin irritation.

3. Systemic Chemotherapy

Drugs like cisplatin, carboplatin, and 5-fluorouracil are commonly used, either alone or in combination with radiation (chemoradiotherapy). This may result in nausea, fatigue, immune suppression, and mucositis.

B. Advanced Treatments for Head and Neck Cancer

Technological advancements have enabled more targeted, less invasive options:

1. Microinvasive Therapies and Surgeries

  • Cryosurgical Ablation:
  • Extreme cold is applied to destroy cancer tissue. It can be used for superficial lesions in the oral cavity, pharynx, or nasal regions. May enhance immune responses post-ablation (cryo-immunology).

2. Targeted Therapies

I. Microvascular Interventional Chemo

In some advanced head and neck cancers, chemotherapy drugs are directly infused into blood vessels feeding the tumour, increasing drug effectiveness and reducing systemic toxicity.

II. Targeted Drug Therapy

Cetuximab (EGFR inhibitor) and pembrolizumab (PD-1 inhibitor) are approved for advanced and recurrent head and neck squamous cell carcinoma. They provide targeted treatment with fewer side effects than traditional chemotherapy.

3. Targeted Radiation Therapy (Brachytherapy / Radioembolization)

Though less common, radioactive seed implants have been used experimentally for small head and neck tumours. Sophisticated imaging and 3D planning allow precise dose delivery.

4. Stem Cell Therapies and Immunotherapies for Head and Neck Cancer

Immunotherapy is emerging as a key treatment, especially in metastatic or recurrent disease. Agents like nivolumab and pembrolizumab (checkpoint inhibitors) have shown prolonged survival and durable response. CAR-T cell therapy is under clinical investigation for use in head and neck cancers.

Prevention and Lifestyle Management

Proactive measures significantly reduce the risk of head and neck cancers:

  • Quit smoking and avoid all forms of tobacco
  • Limit or avoid alcohol consumption
  • Get vaccinated against HPV
  • Practice good oral hygiene and routine dental checkups
  • Use protective gear in occupational environments
  • Regular screening for individuals with a family history or prior head and neck malignancy

Awareness and lifestyle changes are vital components of cancer prevention.

Prognosis and Survival Rates

Prognosis varies by cancer site and stage at diagnosis. Early-stage head and neck cancers have a 5-year survival rate between 70% and 90%. However, the survival drops to around 50%-60% for advanced-stage cases. HPV-positive oropharyngeal cancers typically have better outcomes than HPV-negative tumours. Combining surgery, radiation, and immunotherapy significantly enhances prognosis in appropriate cases.

Conclusion

Head and neck cancer encompasses a wide range of malignancies affecting critical life functions. While many cases are preventable through lifestyle modifications, early detection remains key to improved survival. Advances in targeted therapy, minimally invasive surgery, and immunotherapy are rapidly transforming the treatment landscape. Multidisciplinary management and public awareness campaigns will be instrumental in reducing the global burden of this challenging disease.