Intensity-modulated radiotherapy improves outcomes in postoperative patients with squamous cell carcinoma of the oral cavity

Abstract

Objectives: We compared the outcomes and survival rates of patients with oral cavity squamous cell carcinoma receiving postoperative conventional radiotherapy (RT) or intensity-modulated radiotherapy (IMRT).

Materials and methods: From January 2005 to September 2008, medical records of 131 consecutive patients with oral cancer receiving postoperative radiotherapy in the Department of Radiation Oncology of National Cheng Kung University Hospital were reviewed. Patients were divided into two groups according to the administration of postoperative conventional RT or IMRT. The loco-regional control, survival, and other prognostic factors were compared.

Results: The 3-year Kaplan-Meier estimates of overall survival for patients receiving conventional RT and IMRT groups were 51.2% vs. 69.4% (p=0.079), respectively. The 3-year local-regional control (53.5% vs. 76.3%; p=0.020) and disease-free survival rates (47.8% vs. 70.0%; p=0.027) were significantly increased in the IMRT group. This retrospective study also identified that extracapsular spreading, margin positive/close (≤ 2mm), more advanced T stage (T3-4 vs. T1-2), and conventional RT method were associated with worse prognosis.

Conclusions: The addition of chemotherapy to adjuvant radiotherapy is recommended in patients with above risk factors. Our result underscores that IMRT should be considered to apply to OSCC patients referred for postoperative treatment.