Treatment Outcome of Combined Modalities for Buccal Cancers: Unilateral or Bilateral Neck Radiation?

Purpose: To evaluate the outcome of treatment for buccal cancers and assess the impact of unilateral vs. bilateral adjuvant neck radiation. Methods and Materials: We retrospectively reviewed the course of 145 patients newly diagnosed with buccal squamous cell carcinoma without distant metastases who completed definitive treatment between January 1994 and December 2000. Of 145 patients, 112 (77%) had Stage III or IV disease. All underwent radical surgery with postoperative radiotherapy (median dose, 64 Gy), including unilateral neck treatment in most (n = 120, 82.8%). After 1997, cisplatin-based concomitant chemoradiotherapy was given for high-risk patients with more than two involved lymph nodes, extracapsular spread, and/or positive margins. Results: The 5-year disease-specific survival rate for Stages I-IV was 87%, 83%, 61%, and 60%, respectively (p = 0.01). The most significant prognostic factor was N stage, with the 5-year disease-specific survival rate for N0, N1, and N2 being 79%, 65%, and 54%, respectively (p = 0.001). For patients with more than two lymph nodes or positive extracapsular spread, cisplatin-based concomitant chemoradiotherapy improved locoregional control (p = 0.02). Locoregional control did not differ between patients undergoing unilateral or bilateral neck treatments (p = 0.95). Contralateral neck failure occurred in only 2.1%. Conclusions: In patients with buccal carcinoma after radical resection, ipsilateral neck radiation is adequate. Bilateral prophylactic neck treatment does not confer an added benefit.