Pharyngeal cancer

Pharyngeal cancers include all malignant tumors arising in the nasopharynx, oropharynx, hypopharynx, and tonsils.These cancers are most commonly squamous cell carcinomas. Alcohol and tobacco use are the two most important risk factors and are responsible for the majority of cases. Other risk factors include certain viral infections, poor oral hygiene, and workplace-related exposures, such as radiation. The clinical presentation depends on the location of the tumor. Symptoms may include a growing cervical lump, persistent sore throat, dysphagia, or a change in voice. Diagnosis is confirmed based on tissue biopsy, whereas the extent of spread is determined via imaging modalities like CT or MRI. Treatment usually requires a combination of surgery, radiation therapy, and chemotherapy.

• Oropharyngeal cancer ^[1]
  • Incidence: an estimated 54,010 new cases in the US in 2021
  • ♂ > ♀ (2:1)
• Nasopharyngeal cancer ^[2]
  • Nasopharyngeal cancer is rare in the United States (< 1:100,000)
  • Most common in patients of Mediterranean and southern Chinese (including Hong Kong) descent
  • About 85% of all new cases are diagnosed in Asia. ^[3]
• Hypopharyngeal cancer: uncommon condition ^[4]
  • Incidence: 2,500 new cases in the US annually
  • Peak age: between 50–60 years of age

Epidemiological data refers to the US, unless otherwise specified.

• Risk factors
  • HPV infection
  • Tobacco consumption
  • Alcohol use
  • Nitrosamine consumption from salted/preserved foods
  • Obesity
  • Chronic iron deficiency
  • Long-term consumption of carcinogenic food (e.g., aflatoxin)
  • Exposure to radiation
• Associations
  • Nasopharyngeal carcinoma: EBV infection
  • Oropharyngeal carcinoma and tonsillar cancer: human papillomavirus infection
  • Diseases causing atrophy of the mucosa (e.g., Plummer-Vinson syndrome)

Pharyngeal cancer is usually asymptomatic for a long time. . Often, the first manifestations are swollen cervical lymph nodes.

Oropharyngeal cancer and hypopharyngeal cancer

• Common early symptom: local lymph node metastases causing enlarged cervical lymph nodes
• Foreign body sensation, dysphagia, sore throat
• Muffled voice
• Severe ear pain

Nasopharyngeal cancer ^[2]

• Painless lymphadenopathy
• Unilateral nasal discharge, nosebleeds, impaired nasal breathing (due to obstruction)
• Obstruction of the Eustachian tube: recurrent otitis media (may be accompanied by effusion); conductive hearing loss, tinnitus
• Infiltration of caudal cranial nerves → Garcin syndrome
• Sore throat
• Headache

Tonsillar cancer

• Persistent sore throat, globus sensation, dysphagia
• Unilateral otalgia
• Unilaterally indurated, ulcerated, and/or enlarged tonsil
• Enlarged cervical lymph nodes
• Halitosis
• Blood-tinged sputum
• Trismus (sign of local invasion)

Metastatic disease

• See “Clinical features of oral cavity cancer” for details.

References: ^[5]

• Panendoscopy with biopsy: visualization of the tumor and surrounding anatomy
• Histopathological examination (confirmatory test)
  • Determines type, grade, and extent of the tumor
  • Pleomorphic cells and mitotic figures are seen in tissue samples from lesions which have undergone neoplastic change (from dysplasia to SCC).
• CT or MRI imaging: assesses tumor infiltration depth and invasion of surrounding structures for staging

Approach

Treatment depends on the type of pharyngeal cancer, cancer stage, and individual patient factors (e.g., comorbidities). There is not a clear superior regimen for most stages, so treatment options must be carefully evaluated on a case-by-case basis. Management options include radiation therapy, chemotherapy, different surgical approaches, or a combination of measures.

• Poor prognosis since tumors are commonly discovered in late stages
• 5-year survival rate 64%

References:^[6]