Laryngeal carcinoma

Laryngeal carcinomas are malignant tumors that arise in the supraglottic, glottic (i.e., involving the vocal cords), and subglottic regions of the larynx. Laryngeal cancers are most commonly squamous cell carcinomas. Smoking and alcohol consumption are the most important risk factors. Glottic cancer is the most common subtype and typically manifests with hoarseness in early stages. Diagnosis is based on tissue biopsy under direct laryngoscopy, and staging is determined via imaging such as CT scan or MRI. Treatment varies based on the site and stage of the tumor. Early-stage cancers are usually treated with radiation therapy or transoral laser microsurgery with the goal of voice preservation. Advanced stages often require laryngectomy. Patients with supraglottic or subglottic cancer often present later than those with glottic cancer, which typically results in a poorer prognosis. Vocal rehabilitation is indicated after laryngectomy to help patients regain speech production.

• Sex: ♂ > ♀
• Age of onset: 40–70 years

References:^[1]

Epidemiological data refers to the US, unless otherwise specified.

• Tobacco use
• Alcohol use
• Exposure to asbestos
• Precancerous lesions: leukoplakia or laryngeal papillomatosis in adults (see “Precancerous lesions of the larynx”)
• Irradiation of the head and neck region
• Infection with high-risk HPV (e.g., type 16 or 18) ^[3]
• Betel nut chewing
• Diets rich in salt-preserved meats (nitrosamines) and dietary fats

Laryngeal carcinomas are classified according to their location in relation to the glottis.

• Glottic carcinoma/vocal cord carcinoma (most common form: approximately 60% of cases)
• Supraglottic carcinoma (approximately 40% of cases)
• Subglottic carcinoma (approximately 1% of cases)

Laryngeal carcinomas are almost always squamous cell cancers (SCC)!

References:^[4]

• Hoarseness/change in voice
• Foreign body sensation
• Dyspnea
• Dysphagia
• Stridor (due to airway narrowing)
• Aspiration while eating or drinking

Unexplained hoarseness for longer than 3 weeks should always be investigated by laryngoscopy!

References:^[5]

Initial workup ^[2][6]

Patients with clinically suspected laryngeal cancer should be promptly referred to otolaryngology.

• Visualization
  • Flexible nasopharyngoscopy or direct laryngoscopy: to visualize irregular, nodular, and/or ulcerative lesions
  • Stroboscopic examination: to assess vocal cord mobility during phonation
• Biopsy
  • Required for definitive diagnosis
  • Obtain tissue from the lesion of interest and any lesions on the contralateral arytenoid, anterior commissure, and interarytenoid area.
• Histopathology
  • Used to differentiate laryngeal cancer from benign laryngeal lesions (e.g., vocal nodules and polyps)
  • 90–95% of laryngeal cancers are squamous cell carcinomas. ^[6]

Further workup ^[7]

Order staging imaging if malignancy is confirmed.

• MRI and/or CT neck with IV contrast: to assess local and regional disease extent (e.g. lymph node involvement)
• FDG PET-CT scan: to assess for distant metastasis

• Vocal cord polyp
• Vocal cord nodule
• Vocal cord cyst
• Laryngeal papillomatosis
• Laryngeal amyloidosis
  • A localized form of amyloidosis that only involves the larynx.
  • Manifestations include hoarseness, globus sensation, hemoptysis, stridor, and dyspnea.
  • Laryngoscopy typically shows a firm, orange-yellow to gray epithelial nodule on a vocal cord.

The differential diagnoses listed here are not exhaustive.

General principles ^[2]

• Individualize treatment in consultation with a multidisciplinary tumor board.
• Obtain pretreatment evaluations from a speech pathologist, dietitian, and, if radiation therapy is planned, a dental specialist.
• Treatment is based on tumor location and stage, comorbidities, performance status, and goals of care.
• After treatment, regularly monitor for recurrence.

A patient with laryngeal carcinoma is at risk for airway obstruction. See “Airway management in head and neck cancer” before procedural sedation and/or airway manipulation.

Treatment modalities ^[2]

Management includes one or more of the following options:

• Radiation therapy: all stages
• Cisplatin-based chemotherapy: advanced stages (T3-T4)
• Surgery
  • Transoral laser microsurgery: early stages (T1-T2)
  • Laryngectomy (extent depends on tumor characteristics): all stages

Larynx-preservation techniques should be preferred if appropriate.

Posttreatment voice rehabilitation ^[2]

Voice rehabilitation is used to help patients regain speech production after laryngectomy.

• Tracheoesophageal prosthesis (e.g., Blom-Singer valve)
  • Preferred first-line option
  • Diverts air from the trachea to the pharynx while blocking food from entering the trachea
  • Placed during initial laryngectomy (primary placement) or after radiation therapy (secondary placement)
• Alternative options
  • Esophageal speech: an alternative method of speaking that involves swallowing air and directing it into the upper esophagus
  • Electrolarynx: a device that, when pressed against the soft tissue of the throat, produces pharyngeal vibrations to allow speech production

Posttreatment monitoring ^[8]

• All patients should undergo a regular history, physical examination, and endoscopy to assess for recurrence.
• Assess thyroid function (e.g., TSH levels) every 6–12 months after radiation therapy. ^[8]
• Order imaging for selected patients.
  • T3/T4 or N2/N3 disease: baseline imaging of the primary site with FDG PET-CT scan within 6 months of treatment ^[8][9]
  • Any cancer stage with signs of recurrence: FDG PET-CT scan

After radiation therapy, measure TSH levels every 6–12 months to assess for radiation-induced thyroid dysfunction. ^[8]

Management of recurrence ^[10]

• Localized disease: surgical resection ± adjuvant therapy
• Unresectable nonmetastatic disease: radiation therapy or chemoradiotherapy
• Metastatic disease
  • Curative intent: platinum-based chemotherapy and immunotherapy (e.g., pembrolizumab)
  • Noncurative intent: palliative chemotherapy and/or radiation therapy

• Five-year survival rates after initial diagnosis of laryngeal cancer vary by disease stage. ^[11]
  • Overall (all stages): ∼ 62%
  • Localized disease (no spread): ∼ 79%
  • Regional disease (spread to lymph nodes): ∼ 48%
  • Distant disease (metastatic): ∼ 34%
• Five-year overall survival rates also vary greatly by site. ^[9]
  • Glottic region: ∼ 64%
  • Supraglottic and subglottic regions: ∼ 40%