Hypopharyngeal Cancer

Excerpt

Hypopharyngeal cancer describes tumors arising between the oropharynx and the esophageal inlet, more precisely defined as between the level of the hyoid bone and the lower end of the cricoid cartilage, respectively. This group of cancers is further subdivided based on the anatomical locations within this area, namely post cricoid (the pharyngoesophageal junction), the piriform sinus, and the posterior pharyngeal wall. Hypopharyngeal cancers do not include carcinoma of the larynx as these are anatomically, pathologically, and therapeutically distinct.

Squamous cell carcinoma arising from the mucosal layer is the most common histology identified in 95% of the cases, while adenocarcinoma, sarcoma, and non-epidermoid carcinoma account for the remaining cases. Tumors of the hypopharynx are characterized by local invasion and lymphatic spread, with 70% of patients presenting with lymph node involvement at the time of diagnosis.

Symptomatic burden from hypopharyngeal cancer is determined by the size and location of the primary tumor. Pain, bleeding, and dysphagia are the most common presenting complaints, with concomitant malnutrition a poor prognostic factor. Advanced tumors may invade the larynx giving features of airway compromise and aspiration. Surgical management requiring a combination of partial or total pharyngectomy and laryngectomy dependent on site and stage at presentation can lead to significant functional morbidity.

Hypopharyngeal cancer has an annual incidence of approximately 3,000 cases per year in the United States, accounting for around 7% of upper aerodigestive tract cancers. The prognosis is often worse due to the advanced stage commonly seen at presentation while considerably rarer than laryngeal cancer. The rate of nodal involvement and metastasis is high at diagnosis, with 50% to 70% of patients presenting with N1 disease or worse. Prognosis in hypopharyngeal cancer is dictated by stage with early disease (T1-T2) having a 60% 5-year survival compared with less than 25% in larger tumors (T3-T4) or those with multiple nodal spread.