Laryngeal Cancer
Laryngeal cancer, also known as laryngeal carcinoma, is a malignancy that develops in the larynx, commonly referred to as the voice box. Most of these cancers are squamous-cell carcinomas, meaning they originate from the epithelium—the thin layer of tissue that lines the inside of the larynx.
The prognosis and treatment of this disease are heavily influenced by where the tumor is located. For medical staging, the larynx is divided into three primary anatomical regions: the glottis (which includes the true vocal cords), the supraglottis (the area above the vocal cords, including the epiglottis), and the subglottis (the area below the vocal cords). While tumors can appear in any of these regions, the majority originate in the glottis.
Key Facts
- Primary Cause: Tobacco smoking and heavy alcohol consumption are the leading risk factors; combined use accounts for 89% of cases.
- Common Site: Most laryngeal cancers begin in the glottis (vocal cords).
- Global Impact: In 2018, there were approximately 177,000 new cases and 94,800 deaths worldwide.
- Survival Rate: The five-year survival rate in the United States was 62.1% between 2015 and 2021.
- Spread: Cancer can spread via direct extension to nearby tissues, through the lymphatic system to cervical lymph nodes, or via the bloodstream, most commonly to the lungs.
Signs and Symptoms
Symptoms vary depending on the size and location of the tumor. Because the larynx is central to breathing and speaking, changes in these functions are often the first warning signs.
- Voice Changes: Persistent hoarseness or other alterations in voice quality.
- Throat Sensations: A sore throat or the feeling that something is stuck in the throat.
- Physical Signs: A visible or palpable lump in the neck.
- Respiratory Issues: A persistent cough or stridor (a high-pitched wheezing sound caused by a narrowed airway).
- Other Indicators: Difficulty swallowing, bad breath, or earache caused by referred pain.
Risk Factors
The strongest link to laryngeal cancer is tobacco smoking. Research indicates that heavy smokers are 20 times more likely to die from this cancer than non-smokers. Regular consumption of alcohol, particularly spirits, also increases risk. When tobacco and alcohol are used together, the risk increases synergistically.
Other contributing factors include:
- Occupational Hazards: Exposure to wood dust, paint fumes, and chemicals used in the textile, plastics, petroleum, and metalworking industries.
- Viral Infections: Certain strains of Human Papillomavirus (HPV).
- Medical History: Individuals with a history of head and neck cancer have a roughly 25% risk of developing a second primary cancer in the head, neck, or lungs due to a "field change effect," where tissues become more susceptible to malignant changes.
Diagnosis and Staging
Diagnosis begins with a comprehensive medical history and physical examination. Doctors palpate the neck and supraclavicular fossa to check for enlarged lymph nodes (cervical adenopathy) or laryngeal crepitus.
To visualize the larynx, specialists may use indirect laryngoscopy (using a small mirror) or fibre-optic nasal endoscopy, where a flexible tube is inserted through the nostril. If cancer is suspected, a biopsy is performed under general anesthesia to confirm the histological type and grade of the tumor.
The TNM Staging System
Laryngeal cancer is staged using the TNM system to determine the best treatment path:
- T (Tumour): Describes the size and extent of the primary tumor. It ranges from Tis (carcinoma in situ) to T4 (invasion of deep structures like the carotid sheath or mediastinum).
- N (Node): Evaluates whether the cancer has spread to regional lymph nodes, categorized from N0 (no involvement) to N3 (large or multiple nodes, or extension beyond the node).
- M (Metastasis): Indicates if the cancer has spread to distant organs (M0 for no metastasis, M1 for evidence of distant spread).
| Region | Key Structures | Frequency |
|---|---|---|
| Supraglottis | Epiglottis, arytenoids, false cords | Less frequent |
| Glottis | True vocal cords, commissures | Most common |
| Subglottis | Area below the vocal cords | Less frequent |
Treatment Options
Treatment is multidisciplinary and tailored to the stage and location of the tumor, as well as the patient's overall health.
Surgical Intervention
Surgery may involve the partial or complete removal of the tumor. In advanced cases, a total laryngectomy (full removal of the larynx) may be required.
Adjunct Therapies
Radiotherapy and chemotherapy are often used as adjunct treatments. These may be administered before surgery to shrink a tumor, alongside surgery, or after surgery to eliminate remaining cancer cells.
Supportive Care
Recovery often requires a team of specialists, including speech therapists to help patients regain communication, as well as physical, occupational, and psychological therapists to manage the side effects of treatment, such as changes in appearance or difficulty eating.
Frequently Asked Questions
What is the most common cause of laryngeal cancer?
The most significant risk factors are tobacco smoking and heavy alcohol consumption. The combination of both is especially dangerous, contributing to 89% of all laryngeal cancer cases.
How does laryngeal cancer affect the voice?
Because the cancer often develops in the glottis (where the vocal cords are located), one of the most common early symptoms is persistent hoarseness or other noticeable changes in the voice.
What is stridor?
Stridor is a high-pitched wheezing sound that occurs during breathing. In the context of laryngeal cancer, it is a serious sign that the airway has become narrowed or obstructed by a tumor.
Can laryngeal cancer spread to other parts of the body?
Yes. It can spread directly to adjacent tissues, move to the cervical lymph nodes in the neck, or travel through the bloodstream. The lungs are the most common site for distant metastasis.
What happens if the entire larynx is removed?
A full removal (total laryngectomy) results in the loss of the natural voice. Patients may need to learn alternative methods of speaking or use a voice prosthesis to communicate.