Treatment of Squamous Cell Carcinoma of the Tongue Base: Irradiation, Surgery, or Palliation?

Abstract

Objectives: Squamous cell carcinoma of the tongue base has a poor prognosis, and treatment is accompanied by a number of major problems. In view of this, it is important to recognize which patients will benefit from treatment with curative intent and which treatment method to use. Methods: One hundred sixty-five patients with squamous cell carcinoma of the tongue base were identified on our database. Eighty-two patients were treated by radical irradiation, and 41 by surgery. A further 42 patients were considered unsuitable for curative treatment. Results: The 5-year cause-specific survival rate was 41% for those treated by irradiation, 58% for those treated by surgery, and 9% for untreated patients. There was no difference in the efficacy of treatment methods (p = .5362), but a highly significant difference was seen in survival rate between treated and untreated patients (p = .0028). The decision regarding administration of curative treatment was based on the extent of locoregional involvement at the primary site (p = .0139; odds ratio, 0.43) and in the neck (p = .0078; odds ratio, 0.23). No factors affected the decision to treat by irradiation or surgery. When the observed survival rate was calculated, there was no significant difference in 5-year survival rate between treated and untreated patients (p = .2762). Those with early (T1-2) disease at the primary site had an improved survival rate from 0.5 to 4 years compared with those who were untreated (T3-4; p = .0081; odds ratio, 2.2). In addition, those with early (T1-2) disease had a better survival rate than those with advanced cancers (p = .0139; odds ratio, 2.09). There was, however, no difference in survival rate at 5 years. Those with early disease compared with those with advanced disease were twice as likely to be alive at 2 years; however, all survival advantages had disappeared by 5 years. Conclusions: In terms of observed survival, treating tongue base squamous cell carcinoma that is locally advanced (T3-4) at presentation offers no survival advantage over palliation alone. Treating early disease (T1-2) doubles the survival rate for up to 4 years, but by 5 years this survival advantage is lost. The present study finds radiotherapy and surgery to be equivalent at controlling this disease.