The Impact of Computed Tomography on Early Glottic Cancer Outcomes

Abstract

Purpose: Aim of this study was to evaluate the impact of computed tomography (CT)-based simulation and planning on early glottic cancer outcomes and toxicity. Methods: This is a single-institution retrospective study of 253 patients with T1-2 glottic cancer who underwent radiation therapy (RT) from January 1998-2010. Group A (80%) underwent 2-dimensional RT (2DRT) and group B (20%) 3-dimensional RT (3DRT). 76% of patients in group A and 84% in group B had T1 cancer. The median dose and fraction size were 63 Gy and 2.25 Gy, respectively. Results: With a median follow-up of 83, 93, and 30 months for the whole cohort, group A and B, respectively, the loco-regional control (LRC) was 97.6%. The rate of LRC for T1 disease was 99.5% and for T2 disease 91%. According to the RT modality, rates of LRC were 99.4 and 100% in groups A and B for T1, and 89.8 and 100% for T2. Long-term toxicity was negligible in both groups. Kaplan-Meier Curve showed the 5-year cause-specific survival to be 100%. Chi-square and multivariate analysis tests showed a significant relationship between CT simulation (3DRT) and LRC (p < 0.0001). Conclusion: CT-based simulation and planning provided better LRC and less acute side effects compared to 2DRT.