The Impact of Adjuvant Radiotherapy on Survival in T1-2N1 Squamous Cell Carcinoma of the Oral Cavity

Objective

To evaluate the survival impact of postoperative radiation therapy (RT) in patients with early T stage (T1-2) oral cavity squamous cell carcinoma (OCSCC) and a single positive lymph node.

Patients

Between 1983 and 2004, a total of 1539 patients were treated with surgery for T1-2N1 OCSCC.

Main Outcome Measures

The Surveillance, Epidemiology, and End Results database was used to determine whether postoperative RT improves survival in patients with T1-2N1 OCSCC.

Results

Postoperative RT improved the 5-year overall survival rate (41.4% for surgery alone vs 54.2% for surgery plus RT [P < .001]). Improvement in overall survival in patients with T1N1 disease did not achieve statistical significance with the addition of RT in contradistinction to that in patients with T2N1 disease. Adjuvant RT improved survival in patients with T2 tongue and floor of mouth disease (52.3% vs 37.9% [P = .002] and 39.9% vs 17.7% [P = .003], respectively).

Conclusion

In cases involving T1-2N1 OCSCC in the Surveillance, Epidemiology, and End Results database, the use of RT is associated with statistically significant improved overall survival and cause-specific survival in patients with T2 disease, most strongly in the oral tongue and the floor of the mouth.