Purpose: We report the 5-year survival and late toxicity results of a randomized clinical trial, which showed a 3-year improvement in overall survival and locoregional control of stage III or IV oropharynx carcinoma, using concomitant radiochemotherapy (arm B), compared with standard radiotherapy (arm A).
Patients and methods: A total of 226 patients were entered onto a phase III multicenter randomized trial comparing radiotherapy alone (70 Gy in 35 fractions; arm A) with concomitant radiochemotherapy (70 Gy in 35 fractions with three cycles of a 4-day regimen comprising carboplatin and fluorouracil; arm B). Prognostic factors were evaluated by univariate and multivariate analysis. Five-year late toxicity was evaluated using National Cancer Institute Common Toxicity Criteria for neurological toxicity, hearing, taste, mandibula, and teeth damage, and Radiation Therapy Oncology Group toxicity criteria for skin, salivary gland, and mucosa.
Results: Five-year overall survival, specific disease-free survival, and locoregional control rates were 22% and 16% (log-rank P =.05), 27% and 15% (P =.01), and 48% and 25% (P =.002), in arm B and arm A, respectively. Stage IV, hemoglobin level lower than 125 g/L, and standard treatment were independent prognostic factors of short survival and locoregional failure by univariate and multivariate analysis. One or more grade 3 to 4 complications occurred in 56% of the patients in arm B, compared with 30% in arm A (P was not significant).
Conclusion: Concomitant radiochemotherapy improved overall survival and locoregional control rates and does not statistically increase severe late morbidity. Anemia was the most important prognostic factor for survival in both arms.