- Pathologically (histologically or cytologically) proven diagnosis of squamous cell carcinoma of the oropharynx, which include the sites tonsil, base of tongue, soft palate, or posterior oropharyngeal wall. Histologic variants will be included (papillary squamous cell carcinoma and basaloid squamous cell carcinoma). Cytologic diagnosis from a cervical lymph node is sufficient in the presence of clinical evidence of a primary tumor in the oropharynx.