Radiation therapy’s efficacy on tongue cancer: a population-based survival analysis

OBJECTIVE: To identify survival outcomes for patients with oral tongue cancer and the effects of different prognostic factors on survival. METHODS: A study was performed with the Surveillance, Epidemiology, and End Results database to confirm whether survival improved in patients who had received radiation therapy along with surgery compared with others who had received surgery alone. RESULTS: A total of 9,474 patients were included as respondents in the study. Of the group, 2,759 patients had been treated by surgery along with radiotherapy, while 6,714 just had received only surgery. The survival was higher in patients who had been treated by both surgery and radiotherapy. Moreover, old age (P<0.001), being black (P<0.001), distant stage (P<0.001), first malignant primary indicator (P<0.001), being unmarried (P<0.001), and surgery only (P<0.001) were confirmed as significant risk factors associated with low survival rates. Age 50 years and above (hazard ratio: 1.712, 95% CI: 1.550–1.890) was also a significant risk factor. Nevertheless, grade and sex were not independent risk factors. The multivariate model also showed that being black, distant stage, age below 50 years, sex, being unmarried, and surgery were found to be associated with low survival rates (P<0.001). CONCLUSION: Of the patients with tongue cancer, the group treated by both radiation and surgery had better prognosis than the group that had received surgery only. Also, survival showed no difference in terms of sex among the total tongue cancer population, whereas prognosis was found to differ between two genders in the group that had received both radiation therapy and surgery. Nonetheless, grade was not a risk factor for patients with tongue cancer.