Laryngeal Cancer

Everything about the causes, symptoms, treatments, and life expectancy of laryngeal cancer.

Symptoms and Causes

Laryngeal cancer is the formation of malignant tumors in the larynx, a tubular organ connecting the pharynx and trachea. Its functions include allowing air passage to the lungs and producing voice when the vocal cords vibrate.

There is a direct relationship between smoking and laryngeal cancer, as tobacco components are estimated to cause 94% of cases.

Laryngeal cancer can be classified into three types depending on its location:

Glottic cancer: the most common type, affecting the vocal cords. It is usually diagnosed early, resulting in very high survival rates (around 90% at five years).
Supraglottic cancer: arises above the vocal cords. It carries a higher risk of lymph node spread and is often diagnosed at advanced stages. Five-year survival is estimated between 59% and 34%.
Subglottic cancer: very rare, occurring below the vocal cords. It has the poorest prognosis, with five-year survival rates ranging from 65% to 32%.

In most cases, laryngeal cancer is a squamous cell carcinoma, originating from the flat, thin cells lining the larynx. Although uncommon, other histological types may occur, including lymphomas (developing in the laryngeal lymphatic system), sarcomas (arising from laryngeal soft tissues), adenocarcinomas (originating in glandular tissue), or neuroendocrine carcinoma (forming in cells with neural and endocrine characteristics).

The prognosis of laryngeal cancer depends on the time of detection, location, and extent of the tumor. Overall, the five-year survival rate is 61%; however, most patients are diagnosed before cancer cells spread, raising survival to 76%. If metastasis occurs to other parts of the body, survival decreases to 35%.

Symptoms

The most frequent symptoms of laryngeal cancer include:

Dysphonia: changes in tone, timbre, or volume of the voice, usually hoarseness. It is a typical sign of glottic cancer.
Swelling or lump in the neck.
Difficulty swallowing.
Odynophagia: painful swallowing.
Ear pain.
Particularly in subglottic cancer, difficulty breathing due to obstruction of the laryngeal lumen.

Causes

Carcinogens in tobacco smoke induce dysplasia in laryngeal tissue, meaning cellular characteristics change in size, shape, and organization. Laryngeal cancer develops when DNA in these cells is altered, causing abnormal proliferation. Cells also survive longer than normal, accumulating into tumor masses.

Risk Factors

Key risk factors for laryngeal cancer include:

Age: more common after 40 years, especially between 60 and 70.
Sex: higher prevalence in men.
Smoking: risk increases with duration and quantity.
Alcohol consumption.
Combined tobacco and alcohol use significantly increases risk.
Human papillomavirus (HPV) infection.
Gastroesophageal reflux: stomach acids may damage tissues.
Diets high in animal fats and low in fruits and vegetables.
Family history.

Complications

Laryngeal cancer may lead to:

Airway obstruction.
Dysphagia: difficulty swallowing.
Malnutrition.
Total loss of voice.
Metastasis: commonly spreads to the trachea, esophagus, thyroid, and cervical lymph nodes. Distant metastases often affect the lungs, liver, or bones.
Death.

Prevention

Adopting a healthy lifestyle is crucial for preventing throat cancer. General recommendations include:

Avoid smoking.
Limit or avoid alcohol.
Follow a diet rich in fruits and vegetables.
Maintain a healthy weight.
Maintain good oral hygiene.

Which Specialist Treats Laryngeal Cancer?

Laryngeal cancer is managed by medical oncology and radiation oncology specialists.

Diagnosis

Diagnosis requires various tests for detection and staging:

Medical history: collection of patient and family medical background, including presenting symptoms.
Indirect laryngoscopy: examination of the larynx using a mirror inserted into the throat. Light is reflected to visualize structures and detect anomalies. This procedure is painless but may induce nausea.
Direct endoscopy: visualizes areas not accessible by laryngoscopy, using a flexible tube with a camera and light. Local anesthesia is typically used.
Biopsy: tissue sample is taken during endoscopy and analyzed for cancerous cells.
Lymph node cytology: fine-needle aspiration of an enlarged lymph node to assess for tumor cells.
Computed tomography (CT): X-rays from multiple angles provide detailed images, showing tumor size and extent.
Positron emission tomography (PET): radioactive tracer binds to cancer cells; tumors appear brightly on imaging.

Imaging studies are essential for staging laryngeal cancer, which may be:

Stage 0: tumor confined to the surface layer of the laryngeal lining.
Stage I: tumor is deeper but remains above the glottis; vocal cords are unaffected.
Stage II: cancer cells involve multiple areas of the glottis, but vocal cord movement is preserved.
Stage III: tumor remains within the larynx and affects the vocal cords; may extend to adjacent areas and regional lymph nodes.
Stage IV: cancer begins spreading to other organs:

Stage IVA: tumor invades nearby organs (thyroid, trachea, esophagus, tongue) and cervical lymph nodes.
Stage IVB: tumor extends to the spine, carotid artery, or lungs.
Stage IVC: tumor extends to cervical lymph nodes, >6 cm in size, and may have distant metastasis.

Treatment

Treatment must be personalized in a multidisciplinary approach considering tumor location, extent, histological characteristics, stage, and patient health status and needs.

Most effective procedures include:

Radiotherapy: controlled ionizing radiation to the affected area; used preoperatively to reduce tumor size or postoperatively as adjuvant therapy. For tumors limited to one vocal cord, it may be the sole treatment; if surgery is not possible, it is combined with chemotherapy.
Chemotherapy: chemical agents destroy cancer cells.

Conventional chemotherapy: systemic treatment affecting the entire body.
Targeted therapy: drugs specifically targeting cancer-related genes or proteins, minimizing damage to healthy tissue.

Laryngectomy: surgical removal of cancerous tissue with some healthy tissue to ensure recovery.

Partial laryngectomy: only part of the larynx is removed, preserving organ function and speech.

Supraglottic laryngectomy: upper larynx removed; vocal cords preserved; tracheostomy not required.
Cordectomy: only the affected vocal cord is removed.

Total laryngectomy: complete removal of the larynx, used in severe cases; results in permanent voice loss and requires a permanent tracheostomy for breathing.