Comparison of continuous and split-course radiotherapy for nasopharyngeal carcinoma--an analysis of 1446 cases with squamous cell carcinoma grade 3.

ABSTRACT

PURPOSE: An analysis of 1446 cases with squamous cell nasopharyngeal carcinoma Grade 3 was made for the comparison of treatment results of continuous (CG) and split-course (SG) radiotherapy regimens. METHODS AND MATERIALS The patients were given their first definitive radiotherapy at our department from July 1977 to December 1980, 1093 cases by continuous treatment regimen, and 353 cases by split-course regimen. The interval of the split was 10-45 days, mean 28.6 days. Trials were nonrandomized, but the treatment conditions for both groups were the same. RESULTS: The 5-year survival rate was 33.6% for CG, and 26.9% for SG. For Stage III and IV patients, the 5-year survival rate was 31% (290/933) for CG, and 21.5% (36/107) and 18.8% (17/90) for those with a split of 21-30 and 31-45 days, respectively (both p < 0.05); the 5-year local control rate was 27.4% (256/933) for CG, and 15.5% (26/167) (p < 0.01), and 15.5% (14/90) (p < 0.05) for those with a split of 21-30 and 31-45 days, respectively. The metastatic rate in 5-years was 21.59% vs. 27.48% for CG to SG (p < 0.01), but not different statistically for any subgroup. No relation was confirmed between local control rate and radiation dose. CONCLUSION: According to the data obtained in this series, we believe that the treatment results of CG were superior to those of SG, especially for Stage III and IV patients, and those with a split of 21 days or more.