O003

Thursday, November 13th, 2025 17:10 – 17:20
Speaker Mohamed Elsharief

Single Vocal Cord Irradiation (SVCI) vs Whole Laryngealradiotherapy in the treatment of T1aN0 glottic cancer Aprospective randomized trial

Background
Both TLS and radiotherapy are used in the treatment of T1aN0 glottic cancer with
similar oncological outcomes. In contrast to millimetric margins used in TLS, the
standard radiotherapy field still relies on classic 2D box field exposing the whole larynx
to full radiation dose. Retrospective studies suggest excellent local control with single
vocal cord irradiation that targets only the affected vocal cord. So the aim of this study
was to compare the treatment outcome and toxicity of the classic radiotherapy field vs
single vocal irradiation technique
Patients and methods
This is a prospective phase 2 randomized study (clinicaltrial.gov registration
NCT05679856)
58 consecutive patients with T1N0 glottic cancer were included. 29 were randomised to
standard of care whole larynx radiotherapy field that covers the whole larynx with a
prescription dose of 63Gy/28Fs while the other 29 patients were randomised to single
vocal irradiation field with a prescription dose of 58.08Gy/16Fs. Baseline voice handicap
index was recorded before treatment, at end of radiotherapy then during each follow up
visit.

2

Results
Demographic and patients characteristics were comparable between the 2 arms.
The dose to different organs at risk such as the contralateral vocal cord, arytenoid and
supraglottic larynx were statistically lower in the SVCI arm. 2 year local control rate was
100% in SVCI arm and 96% in the whole larynx arm, with no statistical significant
difference. No grade 3 or 4 toxicities were reported in both treatment arms. VHI scores
were comparable at baseline and at end of radiotherapy, but it was statistically
significant better at 2 months post treatment and thereafter in the SVCI arm as
compared to the whole larynx arm
Conclusion
SVCI is effective and safe treatment for T1aN0 glottic cancer with excellent local control
rates and safe toxicity profile. Reported voice quality is much better with SVCI probably
due to sparing of laryngeal substructures. Multicenter studies with larger sample size
are needed to confirm study results so that SVCI could be standard of care in T!aN0
glottic cancer radiotherapy.