Patients with stage IV oropharyngeal cancer -- a type of cancer that develops in the part of the throat just behind the mouth that assists with breathing, talking, eating, chewing, and swallowing -- are often treated with radiation alone or with chemoradiation. The addition of chemotherapy is usually based on the need for radiotherapy sensitizers and the perceived risk for the spread of cancer cells from the original site to other parts of the body.
In the oropharyngeal cancer population with small volume primary disease and moderate metastatic disease in the lymph nodes, the role of chemotherapy is less clear. But, as chemoradiation for oropharyngeal cancer has become more common and survival is stabilizing, the question of long-term function is becoming important. There is an assumption that combined therapy may lead to increased dysphagia, or difficulty in swallowing and feeding tube dependence.
This study is a retrospective chart review of all patients presenting at MD Anderson Cancer Center with T1 or T2 tonsil or base of tongue squamous cell carcinoma and N2a or N2b cervical lymph node metastasis between January 2000 and December 2004. Only patients who received their radiation treatment at this institution were included. Charts were reviewed for demographic features, staging information, and method of treatment. When available, pre- and post-treatment swallowing evaluations were analyzed. The functional outcomes for swallowing were the presence or absence of feeding (PFG) tubes, diet status, and swallow evaluation results including dysphagia and aspiration. The two-tailed Fisher exact test and Pearson's chi square were used for statistical analysis.
120 charts were reviewed - 84 received radiation alone (RT) while 32 received combined chemoradiation (CRT). The overall survival was 98 percent. More CRT patients required PFG tube placement during treatment than RT patients. However, both groups had equal rates of PFG removed and equally returned to an oral diet by one year post-treatment. Patients who did not have a PFG placed during treatment were more likely to return to a regular diet post-treatment. About half of both patient groups received swallowing evaluations. More CRT patients than RT patients had abnormal swallow studies. Severity of patient swallowing complaints did not correlate to their level of swallowing dysfunction.
The past decade has seen a rise in the use of chemoradiation to treat Stage IV oropharyngeal squamous cell carcinoma. For the small primary disease stage III and IV oropharyngeal cancer, there appears to be similar survival with radiation alone versus chemoradiation. Because of this, assessment of long-term quality of life will best determine the optimal treatment for these patients.
The use of chemoradiation to treat low volume stage IV oropharyngeal cancer resulted in a trend towards more swallowing toxicity and PFG placement during and initially after therapy. However, there appears to be no difference in the long-term feeding tube dependence and severe swallowing dysfunction between these patient groups. Further prospective multimodal analysis is needed to fully describe the swallowing and diet differences between these two patient populations.
While this study seems to demonstrate that chemoradiation does lead to worsening swallowing function during the treatment phase (indicated by increased need for inter-treatment feeding tube placement), there does not seem to be any difference in the return to swallowing function within the year (indicated by removal of PFG).
Due to the retrospective nature of this study, there are limitations in the evaluation of swallowing function. Without modified barium swallows and formal speech pathology evaluations on every patient, it is impossible to assess the detailed effects of treatment on swallowing function. To better assess this, a prospective study utilizing pretreatment studies, post-treatment studies and quality of life measurements is needed.