Treatment results of radiotherapy for squamous cell carcinoma of the cheek mucosa

The results of radiotherapeutic treatment in 71 patients with squamous cell carcinoma of the cheek mucosa were reviewed. The actuarial 5-year local control rate was 100% for T1 (8 patients), 62% for T2 (43), 65% for T3 (17) and 0% for T4 (3). The patients were divided into four groups according to treatment modality; group 1 was treated by radiotherapy alone (R), group 2 by radiotherapy combined with chemotherapy of BLM or PEP (R + C), group 3 by external radiotherapy followed by surgery (R + S) and group 4 by a combination of radiotherapy, chemotherapy and surgery (R + C + S). The 5-year local control rate was 44% for R (11 patients), 61% for R + C (39), 63% for R + S (6) and 80% for R + C + S (15). Nine of 14 cases or 64% of the surgical specimens in the R + C + S group showed no tumor cells microscopically, a rate comparable with the 5-year local control rate of the R + C group. Including the results of secondary treatment by surgery for recurrent cases, the ultimate local control rate was 83% in both the R and R + C groups. The local control rate was 88% for carcinoma located in the anterior half of the cheek and 53% for that in the posterior cheek. The results suggested that tumors extending to the bucco-alveolar sulci would be more difficult to control by radiotherapy alone, with or without chemotherapy.