Radiation therapy in T1–T2 glottic carcinoma: influence of various treatment parameters on local control/complications

Abstract

Purpose: To evaluate the influence of various treatment parameters on local control as well as complications in T1 and T2 glottic carcinomas. Methods and Materials: Between 1975 and 1989, 676 patients with early glottic carcinoma (460 T1 and 216 T2) received curative radiation with three different treatment regimens, as follows: Regimen 1—50 Gy/15 Fr/3 weeks (3.33 Gy/daily) for 192 patients; Regimen 2—60–62.5 Gy/24–25 Fr/5 weeks (2.5 Gy/daily) for 352 patients; and Regimen 3—55–60 Gy/25–30 Fr/5–6 weeks (2–2.25 Gy/daily) for 132 patients. Results: The local control at 10 years was 82% and 57% for T1 and T2 lesions respectively ( p = 0.0). For the T1N0M0 group, field size had significant impact on local control with both univariate ( p = 0.05) and multivariate ( p = 0.03) analysis. For T2N0M0, group field size ( p = 0.03) as well as registration year ( p = 0.016) were significant in univariate analysis whereas only field size remained significant on multivariate analysis. Persistent radiation edema was noted in 146 (22%) patients and was significantly worse with larger field size ( p = 0.000) but not related to different treatment regimens. Conclusion: The shorter fractionation schedule had comparable local control, without increased complications in comparison to the protracted schedule and is best suited for a busy department.