Laryngeal Cancer

Laryngeal cancer is cancer of the throat that affects the larynx. The malignant cells in laryngeal cancer can impact the cartilage and muscles. It can also hamper the functioning of your voice box.

Associated Anatomy

The larynx is a triangle-shaped air passage in the neck. It is 2 inches wide and has three parts: glottis, supraglottis, and sub-glottis.

Alternative Name

The most common type of laryngeal cancer is squamous cell carcinoma, with 95% of total cases. Hence, it is also known as squamous cell carcinoma. The common term for laryngeal cancer is throat cancer.

Signs or Symptoms of Laryngeal Cancer

Signs and symptoms of laryngeal cancer include:

• Cough
• Difficulty in swallowing
• Pain in ears
• Sore throat
• Loss of weight
• Lump in the throat
• Hoarseness of voice
• Frequent choking of food

Causes of Laryngeal Cancer

• The exact cause of laryngeal cancer is not known.
• Genetic mutations are the most common cause of the development of laryngeal cancer. These gene mutations can occur due to exposure to risk factors.
• Mutations can also occur due to poor nutrition, poor immune system, and exposure to toxins like asbestos, e.g., mutation of the p16 gene (tumor suppressor gene).
• Human Papilloma Virus is also a known cause of laryngeal cancer.

Various Stages of Laryngeal Cancer

Staging of laryngeal cancer uses the TNM staging method. There are five stages of laryngeal cancer.

• Stage 0: In this stage, the cancer cells are present only on the inner lining of the larynx and have not invaded surrounding tissues.
• Stages 1 and 2: These are considered early stages.
• Stage 3: It involves the advancement of cancer cells locally. In this stage, the cancer cells also spread to lymph nodes.
• Stage 4: It is an advanced stage. During this stage, laryngeal cells metastasize to different parts of the body.

Possible Treatment For Laryngeal Cancer

Treatment of any cancer depends on the stage of cancer.

• For treatment at the early stage, radiation therapy or surgery can be beneficial.
• The surgery can include endoscopic resection, partial removal of the larynx, or complete removal of the larynx.
• Radiation therapy kills cancer cells and helps in the shrinking of the tumor. Chemotherapy is a combination of drugs that can kill cancer cells. In cases where laryngeal cancer gets detected at advanced stages, chemotherapy can be effective if combined with radiation therapy and surgical treatment.
• Supportive treatment includes speech therapy and therapy to help in swallowing and chewing.

Risk Factors Associated With Laryngeal Cancer

• The most significant risk factor associated with laryngeal cancer includes smoking.
• Alcohol consumption is also considered a risk factor for laryngeal cancer.
• Vitamin deficiency and poor nutrition
• Male patients above the age of 40 years are more prone to develop laryngeal cancer
• Previous history of cancer in head and neck region
• Prolonged exposure to chemicals like paint fumes, metal residues

Possible Complication of Laryngeal Cancer

The spread of laryngeal cancer can lead to obstruction in the airway and difficulty in swallowing. If the mass expands and spreads further, it can cause disfiguration of the face and neck. It is also associated with hard skin on the neck. If laryngeal cancer involves vocal cords, the patient will experience a loss of speaking ability.

Typical Test For Laryngeal Cancer Treatment

For the diagnosis of laryngeal cancer, your doctor performs a series of tests. The first test includes a laryngoscopy to examine the inside of the larynx. In case of abnormal findings in laryngoscopy, a small tissue sample is taken for biopsy to identify cancer. Cancer in the advanced stages is detected by using CT scans and MRIs. These tests are also helpful for detecting metastasis to other organs.

Laryngeal Cancer Prevention

Primary Prevention

Primary prevention includes changing the lifestyle to decrease the risk factors associated with the development of laryngeal cancer. These include:

• Eliminating the use of tobacco in all forms and quitting smoking
• Limiting the intake of alcohol to moderate levels
• In case of workplace exposures, use safety equipment.
• If possible, limit the exposure to hazardous chemicals like asbestos
• Increasing the intake of food rich in antioxidants and other essential nutrients.
• HPV vaccination

Secondary Prevention

Secondary prevention includes:

• Physical examination at scheduled intervals
• If the patient has received radiation therapy, secondary prevention includes immediate nasendoscopy.
• Imaging studies, including CT scan and MRI at routine intervals
• In the case of radiation therapy, thyroid-stimulating hormone testing needs to be done every year.
• If the oral cavity is exposed to radiation, dental screening has to be performed at regular intervals.

Differential Diagnosis of Laryngeal Cancer

• Bacterial lymphadenopathy
• Chronic laryngitis
• Hemangioma
• Bacterial cleft cyst
• Laryngocele
• Polyps in vocal cords
• Chronic sialadenitis
• Acute sialadenitis
• Benign tumor

Epidemiology

• Laryngeal cancer occurs in one-third of cases with head and neck cancer.
• The mean age of the patient is 65 years.
• Males are more prone to develop laryngeal cancer as compared to females.
• 98% of the total cases of laryngeal cancer occur in supraglottic and glottic regions.
• The subglottis is involved in only 2% of cases.

Pathophysiology

The majority of laryngeal cancers are squamous cell carcinomas. These squamous cells help in the protection of the upper respiratory tract. Due to exposure to risk and genetic factors, the genes controlling the growth of these squamous cells undergo mutation. These mutations also lead to the inactivation of tumor suppressor genes and the activation of oncogenes. These changes lead to the uncontrolled proliferation of squamous cells.

Expected and Natural Prognosis

The prognosis of patients with laryngeal cancer depends on the time of diagnosis, type and grade of cancer cells, and the anatomical location of the cancer. Approximately 61% of patients have a 5% survival rate. In the case of early diagnosis, the 5-year survival rate increases to 78%.