Squamous Cell Carcinoma of the Base of Tongue Treated with External Beam Radiation Therapy: A Preferred Alternative to Surgery
Presenter: Mendenhall WM et al
Affiliation: University of Florida College of Medicine
Surgery has traditionally been the mainstay of treatment for squamous cell carcinoma of the base of tongue. However, the morbidity with this surgery is significant. This retrospective study was performed to compare outcomes with definitive radiation and surgery in an attempt to spare patients significant, life long, surgical morbidity.
Two hundred seventeen patients with squamous cell carcinoma of the base of tongue were treated with radiation therapy alone or with a planned neck dissection for residual disease in the lymph nodes. An important point is that this series is relatively unselected as the majority of patients at this institution are treated with radiation therapy which is considered the treatment of choice by surgeons and radiation oncologists. Hence, all stages of disease are represented. The majority of the patients were treated with twice daily fractions of radiation.
- The minimum followup was 2 years with > 5 years of followup in 79%.
- Local control at five years was 96% for T1 tumors, 91% for T2 tumors, 81% for T3 tumors, and 38% for T4 tumors. The overall local control was 79%.
- Multivariate analysis revealed prognostic factors of T stage and overall treatment time predicted for local control.
- The five year overall local-regional control was 75%.
- T stage, overall treatment time, overall stage, and the addition of a neck dissection predicted for the likelihood of local-regional control.
- The five year overall survival rate was 50%.
- These results were compared to standard surgical series from the literature which report local control rates of 70 to 80%, local-regional control rates of 60 to 75%, and overall survival rates of 40 to 50%.
- Severe complication rates for standard surgical series range around 25% with a 2% to 4% rate of fatal complications. Severe radiation complications developed in 4% of this series with no treatment related deaths.
- Radiation therapy appears to produce similar rates of local-regional control and survival when compared to surgery. This is accomplished with less morbidity.
- The likelihood of local-regional control appears to be related to stage, overall treatment time, and the addition of a planned neck dissection.
- This series provides evidence to allow patients with this disease an alternative to immediate radical surgery. Future directions for treatment with organ preservation might include the use of chemotherapy in addition to radiation.
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