Laryngeal Cancer: Basic Knowledge and Things to Note

1. Introduction to the Larynx:

• Anatomy: The larynx is part of the upper respiratory tract, situated between the pharynx and the trachea. Its primary functions include voice production, breathing, and protecting the respiratory tract. The larynx is divided into three parts:

• Supraglottis: Comprises the Morgagni’s ventricle, ventricular band, and epiglottis.

• Glottis: Contains the two vocal cords, representing the narrowest part of the larynx.

• Subglottis: Extends from the inferior surface of the vocal cords to the first tracheal ring.

• Laryngeal Margin: Includes the epiglottic margin, the aryepiglottic fold, and the arytenoid cartilage.

2. Laryngeal Cancer:

• Definition: Laryngeal cancer is a malignant tumor arising from the epithelial lining of the larynx. It can occur at three levels: supraglottis, glottis, or subglottis.

• Prevalence: Laryngeal cancer is more prevalent in developed countries like Europe and the United States. In Vietnam, laryngeal cancer is more common than hypopharyngeal cancer.

• Sex Ratio: Men are more likely to develop laryngeal cancer than women (9:1).

• Age Group Most Affected: 40-69 years old.

3. Causes of Laryngeal Cancer:

• Risk Factors:

• Tobacco Smoking: This is the primary risk factor.

• Alcohol Consumption: Increases the risk of laryngeal cancer.

• Environmental Factors: Working in environments exposed to chemicals, wood dust, smoke, etc.

• Radiation Therapy: Prior radiation therapy to the neck area can increase the risk of laryngeal cancer.

• Chronic Infections: Chronic laryngitis caused by infections can also increase the risk.

• Precancerous Conditions:

• Keratosis: An abnormal thickening of the skin.

• Leukoplakia: White patches on the mucous membrane.

• Vocal Cord Papilloma: Benign growths on the vocal cords.

4. Clinical Manifestations:

• Early Symptoms: Hoarseness, voice changes, often prolonged and of unknown origin.

• Late Symptoms:

• Cough, dry cough, possibly with blood-streaked sputum due to frequent coughing that irritates blood vessels.

• Neck pain that may radiate to the ear.

• Laryngeal discomfort.

• Laryngeal breathing difficulties.

• Difficulty swallowing if the cancer spreads to the hypopharynx.

5. Metastasis:

• Lymph Nodes: The middle cervical lymph nodes are the most common site for lymph node metastasis.

• Distant Metastasis: Can spread to the lungs, liver, bones, brain, etc.

6. Diagnosis:

• Laryngoscopy: Examination using a mirror or endoscopy to assess the lesion.

• Biopsy: Tissue samples are taken to identify cancer cells.

• Imaging Tests:

• X-ray of the neck and chest.

• CT scan of the neck and chest.

• MRI.

• Blood Tests: Assess overall health status.

7. Treatment:

• Surgery:

• Tumor removal.

• Total or partial laryngectomy.

• Radiation Therapy:

• Using radiation to destroy cancer cells.

• Chemotherapy:

• Using anticancer drugs to kill cancer cells.

• Combined Therapy: Combining surgery, radiation therapy, and chemotherapy.

8. Prognosis:

• Early Stages: Good prognosis, with the potential for a cure.

• Late Stages: Poorer prognosis, with lower survival rates.

9. Things to Note:

• Prevention:

• Quit smoking.

• Limit alcohol intake.

• Regular health checkups.

• Work in safe environments.

• Early Diagnosis:

• Pay attention to unusual symptoms in the larynx, especially persistent hoarseness.

• Consult an otolaryngologist if there are any suspicious signs.

• Proper Treatment:

• Follow the doctor’s instructions.

• Avoid self-treating.

• Post-treatment Care:

• Regular health monitoring.

• Managing post-treatment complications.

10. Multiple Choice Quiz:

• Question 1: The narrowest part of the airway is:

• A. Larynx

• B. Glottis

• C. Supraglottis

• D. Subglottis

• Answer: B

• Question 2: The most common anatomical site for laryngeal cancer is:

• A. Vocal cords

• B. Ventricular band

• C. Epiglottic mucosa

• D. Arytenoid cartilage mucosa

• Answer: A

• Question 3: Among head and neck cancers, laryngeal cancer is the:

• A. Most common

• B. Second most common

• C. Third most common

• D. Fourth most common

• Answer: B

• Question 4: Laryngeal cancer is most common in the age group:

• A. 31-40 years old

• B. 41-50 years old

• C. 51-60 years old

• D. 61-70 years old

• Answer: C

• Question 5: Which of the following factors is not related to laryngeal cancer:

• A. Tobacco smoking

• B. Chronic laryngitis

• C. Working in a wood dust environment

• D. Adult vocal cord papilloma

• Answer: B

• Question 6: Which anatomical location is difficult to assess when examining the larynx with a mirror or optic device:

• A. Epiglottis

• B. Arytenoid cartilage

• C. Posterior two-thirds of the vocal cords

• D. Anterior one-third of the vocal cords

• Answer: D

• Question 7: Which symptom is characteristic of early-stage glottic cancer:

• A. Hoarseness

• B. Painful swallowing

• C. Coughing up blood

• D. Difficulty breathing

• Answer: A

• Question 8: T1 K laryngeal cancer:

• A. Tumor involving one or two vocal cords, with vocal cord mobility, and normal arytenoid cartilage.

• B. Tumor involving two anatomical locations, with vocal cord mobility, and limited arytenoid cartilage mobility.

• C. Tumor involving one side of the vocal cords, with vocal cord mobility, and normal arytenoid cartilage.

• D. Tumor involving both vocal cords, with vocal cord mobility, and fixed arytenoid cartilage.

• Answer: A

• Question 9: Metastatic lymph nodes in laryngeal cancer are usually found in:

• A. Submental lymph nodes (group I)

• B. Upper cervical lymph nodes (group IIB)

• C. Middle cervical lymph nodes (groups IIA, III)

• D. Lower cervical lymph nodes (groups IV, VI)

• Answer: C

• Question 10: The most common histopathology of laryngeal cancer is:

• A. Well-differentiated squamous cell carcinoma

• B. Undifferentiated squamous cell carcinoma

• C. Connective tissue cancer (sarcoma)

• D. Lymphoid tissue cancer (lymphoma)

• Answer: A

• Question 11: The most appropriate approach for a suspected laryngeal cancer lesion is:

• A. Biopsy three times

• B. Biopsy five times

• C. Biopsy monthly

• D. Repeat biopsy multiple times

• Answer: D

• Question 12: The current primary treatment for late-stage laryngeal cancer is:

• A. Radiation therapy followed by surgery

• B. Surgery followed by radiation therapy

• C. Radiation therapy combined with chemotherapy

• D. Surgery followed by chemotherapy

• Answer: B

• Question 13: Glottic cancer has a better prognosis because:

• A. The tumor grows slowly.

• B. It has a protective anatomical barrier.

• C. It has a very limited lymphatic network.

• D. Treatment is easier.

• Answer: C

• Question 14: Which of the following is not recommended for treating laryngeal cancer:

• A. Immunotherapy

• B. Chemotherapy

• C. Traditional Chinese medicine

• D. Radiation therapy

• Answer: C

• Question 15: Laryngeal cancer can occur at any age.

• A. True

• B. False

• Answer: B

• Question 16: Laryngeal cancer is primarily associated with alcohol consumption.

• A. True

• B. False

• Answer: B (Tobacco smoking)

• Question 17: Difficulty swallowing is not a symptom of laryngeal cancer.

• A. True

• B. False

• Answer: B

• Question 18: Laryngeal cancer can develop on top of a benign tumor.

• A. True

• B. False

• Answer: A

• Question 19: Total laryngectomy will permanently cause all patients to lose their voice.

• A. True

• B. False

• Answer: B

• Question 20: Among head and neck cancers, laryngeal cancer has the best prognosis.

• A. True

• B. False

• Answer: A

• Question 21: Weight loss is a very common symptom in laryngeal cancer.

• A. True

• B. False

• Answer: B

• Question 22: Patients with laryngeal cancer may simultaneously have cancer in other locations of the respiratory and digestive tracts.

• A. True

• B. False

• Answer: A

• Question 23: Patients who undergo total laryngectomy cannot breathe naturally.

• A. True

• B. False

• Answer: A