Introduction: This study examines 10-year treatment outcomes in this patient population over the time-span of the changing treatment paradigm.
Methods: A cohort of 290 patients was followed for 344 months (median15 months). Multivariate analysis were used to determine the predictors of 10-year survival after treatment.
Results: The mean age of the cohort was 62.2 years (SD = 12.4 years), 79.7% were males, and 86.4% had Stage III or IV disease at presentation. The overall median survival time was 16 months (95% CI = 9.5, 22.5 months) with 23% of patients surviving the 10-year period. The 10-year disease specific and disease free survival was similar at 30 and 31 months respectively. Survival varied significantly ( P < 0.05) with stage of disease on presentation. Survival probability at 10 years was 37% for stage I disease and 26%, 28% and 23% for stages II–IV respectively. Patients younger than 65 years had better overall survival when compared to those 65 or more: 29% versus 14%, respectively ( P < 0.0001). Similarly, females had better 10-year survival as compared to males, 31% vs. 21%, respectively; however, this difference was not statistically significant ( P > 0.10). A lateral location of the tumor had a better survival outcome when compared to a midline location of (27% or 28% versus 9%, P < 0.0025). With univariate analysis 10 year survival of 54% was observed with chemoradiation, and 45% for surgey + radiotherapy ( P < 0.0001). Multivariate models demonstrated an independent effect of stage, gender, age, and initial treatment modality on overall survival. Treatment with radiotherapy and chemotherapy reduced the risk of death over 10 years by 89% (HR = 0.11; 95% CI = 0.1, 0.2; P < 0.0001) and surgery + radiotherapy reduced the risk of death over 10 years by 87% (HR = 0.13; 95% CI = 0.1, 0.2; P < 0.0001).