Comparison of Voice Outcomes in Early Glottic Cancer Patients after Laser Surgery or Radiotherapy / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Radiotherapy and laser surgery are the main treatment modalities for early glottic cancer. However, which treatment has better voice outcome is unclear. Few studies have considered the effect of radiation dose on voice outcomes after radiotherapy. The purpose of this study was to compare voice outcomes in early glottic cancer patients between two treatment modalities and to identify whether radiation dose affects voice outcomes. SUBJECTS AND METHOD: From January 1995 to December 2010, 66 patients with the early glottic cancer who underwent laser surgery (n=27) or radiotherapy (n=39) were retrospectively investigated. Voice quality was assessed using Computerized Speech Lab and F0, Jitter, Shimmer and noise to harmonic ratio were evaluated. For aerodynamic test, maximum phonation time was also evaluated. RESULTS: F0 differed statistically between the laser surgery group and radiotherapy group. In laser surgery group, F0 was elevated after surgery. On the other hand, F0 decreased statistically after radiotherapy. In the radiotherapy group, the dose was statistically different between the lower and higher dose groups. In T2 stage disease, which received a higher radiation dose, voice outcomes were poorer than in T1a or T1b stage diseases. CONCLUSION: In early glottic cancer, F0 differed statistically between the laser surgery group and the radiotherapy group F0 decreased statistically after radiotherapy. In the radiotherapy group, voice quality was affected by radiation dose as the higher dose resulted in poorer voice outcomes.