T₁N₀/T₂N₀ glottic carcinoma: A comparison of two fractionation schedules

Abstract

The aim of this paper is the retrospective comparison of accelerated/hypofractionated radiotherapy regimen (AHFX) with standard fractionation regimen (SFX) for patients with early glottic carcinoma. One hundred and forty-five patients with T(1)-T(2) glottic cancer between 1986 and 1998 were eligible. Before 1992, patients received 60-66 Gy in 30-33 fractions over 6-6.5 weeks (SFX) with (60)Co and 6-MV beams. After 1992, patients received 52.5-55 Gy in 20 fractions over 4 weeks (AHFX) using 6-MV beams. The end-points were overall survival, laryngectomy-free survival (LFS), loco-regional control and toxicity. One hundred and two were stage T(1)N(0); 43 were stage T(2)N(0). Median follow up was 4.9 years. The 5-year overall survival was 78%. Five-year loco-regional control in T(1)N(0) patients was higher in AHFX than in SFX group (95 vs 75%, P = 0.002). Loco-regional control in T(2)N(0) patients was similar for AHFX and SFX (81 vs 80%, P = 0.813). Overall LFS was 88%. T(1)N(0) AHFX patients had 5-year LFS of 95% compared with 75% for SFX (P = 0.003). For T(2)N(0) AHFX patients, overall LFS was 92% compared with 80% for the SFX group (P = 0.291). No grade 4 or 5 late toxicity occurred. One AHFX patient developed grade 3 toxicity; two of 51 SFX patients developed grade 2 toxicity versus five of 94 AHFX patients. AHFX using 6-MV beams for treatment of early glottic cancer resulted in equivalent LFS and toxicity when compared with SFX.

Hypofractionated Radiotherapy in the Treatment of Early Glottic Carcinoma

“…21-25 Short et al reported 95% locoregional control with accelerated hypofractionated regimen 52.5-55 Gy over 4 weeks compared with 75% when treating with 60-66 Gy over 6-6.5 weeks (p = 0.002). 21 In another study covering 171 patients control rate was significantly improved using 2 Gy than 1.8 Gy per fraction. 23 Patients treated with higher fraction size > 3 Gy have a higher risk of developing late complications and this is in contrast to the findings of the BIR trial.…”

Evaluation of acute/late toxicity and local recurrence in Τ1-Τ2 glottic carcinoma treated with accelerated hypofractionated 3D-conformal external beam radiotherapy (3D-CRT)

“…More specifically, the fraction size has proved to be the only significant predictor for the laryngectomy free survival (LFS) 15,16…”

The impact of conventional or hypofractionated radiotherapy on voice quality and oncological outcome in patients with early glottic cancer

“…Late normal tissue reactions are more dependent on the dose per fraction than acute reactions. Therefore, although there is no doubt that hypofractionation offers major potential advantages to patients and to the economy of health systems, their development should not be at the expense of a lower likelihood of tumour control as well as of an unacceptable late toxicity (1,3,5,16,17). Hypofractionated treatment benefits depend on the fact that these cancer cells, characterized by a slow proliferation, during radiotherapy increase the proliferation rate becoming more radiosensitive (18)(19)(20).…”

“…These treatments offer the same results but their comparative benefits are debated. Even though ELS is quicker, which reduces cost considerably, many institutions prefer to use radiotherapy (1)(2)(3)(4)(5). This choice depends on the fact that the voice function and quality are better preserved after treatment (6)(7)(8)(9).…”

“…Accelerated fractionation RT has considerable benefits in terms of treatment duration and cost compared with conventional fractionation methods (1). Furthermore, the increased single dose radiation and shortened treatment time may improve the local control (5). Various types of fractionation methods are performed in clinical practice but an optimal fractionation protocol has not yet been established.…”