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]
The rate of curability of cancers of the oropharynx varies depending on the stage and specific site. Local control rates for early base-of-tongue cancers approximate 85%. In a large retrospective study involving 262 patients with base-of-tongue cancer, the overall 5-year disease-specific survival rate for patients with all stages of disease was approximately 50%. Treatment modalities included surgery with and without radiation therapy and radiation therapy alone. None of the treatment modalities had a significant survival advantage either overall or within the stages.[44,45]
In a retrospective study involving 162 patients with tonsil carcinoma, 84 patients were treated with primary surgery, which was followed by radiation therapy and/or chemotherapy if histologic signs of aggressive behavior were identified. Survival rates were 89% for stage I, 91% for stage II, 79% for stage III, and 52% for stage IV. In a retrospective study of 188 patients with SCC of the soft palate, uvula, and anterior tonsillar pillar, treatment to the primary site consisted of radiation therapy for 150 patients, surgery for 28 patients, and combined therapy for 10 patients. The overall determinant survival was 80% at 2 years, but it fell to 67% at 5 years. In another retrospective study, 148 patients received definitive radiation therapy for SCC of the pharyngeal wall. Cause-specific survival rates were 89% for stage I, 88% for stage II, 44% for stage III, and 34% for stage IV. Twice-daily fractionation, stage I to stage II disease, and an oropharyngeal primary site were associated with improved locoregional control.