OP062: Hypo-fractionated radiotherapy for T1 glottis carcinoma: The impact of anterior commissure involvement on the treatment outcomeS

Abstract

Objectives To analyze the treatment outcomes in T1 glottis squamous cell carcinoma treated with hypo-fractionated radiotherapy. Methods A retrospective study of 72 consecutive cases of T1 glottic squamous cell carcinoma treated with hypofractionated radiotherapy. The study period was between August 2004 to November 2008. Treatment outcomes in terms of five year overall survival and recurrence free survival and local control rates were analyzed. The difference in outcome between cases with or without anterior commissure involvement and T stage (T1a vs. T1b) were also studied. Kaplan Meier survival curves were used for analysis. Results 71 (98.6%) case were males and only one (1.4%) case was female. 57 patients had unilateral cord involvement (T1a) and 15 patients had bilateral cord involvement (T1b). 20 cases (27.8%) had involvement of anterior commissure. 5 (6.9%) cases had recurrence. All cases were treated with hypo-fractionated radiotherapy with doses ranging from 54 Gy to 60 Gy. The mean follow up period was 35.1 months (range 7–69 months). 69 patients were alive and disease free at the end of the follow up period. The 5-year overall survival was 95.8% and 5-year recurrence free survival rate was 92.3%. The 5-year overall survival rate for cases with and without anterior commissure involvement was 83.7% and 100% respectively ( p = 0.007). Similarly, the 5-year recurrence free survival rate was 97.7%and 78.4% respectively ( p = 0.014). Cases with T1b involvement also had similar poorer outcomes. Conclusion Hypo-fractionated radiotherapy is an effective treatment modality for T1 glottis carcinoma. This study shows poorer treatment outcomes with tumors having anterior commissure involvement. Anterior commissure involvement is a poor prognostic indicator as depicted by significant reduction in 5-year overall and recurrence free survival.