Tumors of the pharyngeal wall are typically diagnosed in an advanced stage because of the silent location in which they develop.[3,13]
Symptoms of pharyngeal wall tumors may include:
- Weight loss.
- A neck mass.
These lesions can spread superiorly to involve the nasopharynx, posteriorly to infiltrate the prevertebral fascia, and inferiorly to involve the pyriform sinuses and hypopharyngeal walls. Primary lymphatic drainage is to the retropharyngeal nodes and level II and III nodes. Because most pharyngeal tumors extend past the midline, bilateral cervical metastases are common.
Precancerous lesions of the oropharynx include leukoplakia, erythroplakia, and mixed erythroleukoplakia. These are clinical terms that have no specific histopathologic connotations. Leukoplakia, the most common of the three conditions, is defined by the World Health Organization as "a white patch or plaque that cannot be characterized clinically or pathologically as any other disease." The diagnosis of leukoplakia is one of exclusion; conditions such as candidiasis, lichen planus, leukoedema, and others must be ruled out before a diagnosis of leukoplakia can be made.
The prevalence of leukoplakia in the United States is decreasing; this decline has been related to a reduction of tobacco consumption. Although erythroplakia is not as common as leukoplakia, it is much more likely to be associated with dysplasia or carcinoma.[5,25]
The clinical anatomic staging of oropharyngeal cancers involves both clinical assessment and imaging techniques.[3,14] One study has reported that positron emission tomography scans are more accurate than computed tomographic scans or magnetic resonance imaging in detecting occult nodal disease. Diagnostic methods involve the molecular analysis of tissue from the margins of lip and oral cavity SCCs (i.e., molecular staging) to detect tumor-associated genetic alterations in cells that appear normal by conventional light microscopy. Molecular staging may predict the likelihood of recurrence and may help to establish the relationship between index lesions of SCCs and subsequent lesions.[27,28]
Traditionally, surgery and/or radiation therapy have been the standards for treatment of oropharyngeal cancers; these treatment modalities are frequently complicated by suboptimal control of locoregional disease and significant long-term functional deficits.[3,29] Although specific indications for primary surgical resection exist, some investigators suggest that the concurrent use of multiagent chemotherapy and radiation has become the standard of care for the management of patients with late-stage disease, and surgery is often reserved for salvage of those patients who fail definitive nonoperative treatment.[27,29,30] Studies using aggressive and uncompromised radiation therapy with concurrent multiagent chemotherapy have consistently demonstrated a survival and locoregional control benefit.[31,32,33,34,35] This treatment approach emphasizes organ preservation and functionality. New treatments under development include various biologic therapies (i.e., vaccines, growth factor-receptor antagonists, cyclin-dependent kinase inhibitors, oncolytic viruses, and others) and photodynamic therapy.[27,36,37,38,39,40,41,42,43]