T1a Glottic Cancer: Advances in Vocal Outcome Assessment after Transoral CO₂-Laser Microsurgery Using the VEM

• Main Authors: Wen Song, Felix Caffier, Tadeus Nawka, Tatiana Ermakova, Alexios Martin, Dirk Mürbe, Philipp P. Caffier
• Format: Article
• Language: English
• Published: MDPI AG 2021-03-01
• Series: Journal of Clinical Medicine
• Subjects: T1a glottic carcinoma; transoral laser microsurgery; treatment outcome; vocal function; objective voice diagnostics; vocal extent measure (VEM)
• Online Access: https://www.mdpi.com/2077-0383/10/6/1250

Patients with unilateral vocal fold cancer (T1a) have a favorable prognosis. In addition to the oncological results of CO₂ transoral laser microsurgery (TOLMS), voice function is among the outcome measures. Previous early glottic cancer studies have reported voice function in patients grouped into combined T stages (Tis, T1, T2) and merged cordectomy types (lesser- vs. larger-extent cordectomies). Some authors have questioned the value of objective vocal parameters. Therefore, the purpose of this exploratory prospective study was to investigate TOLMS-associated oncological and vocal outcomes in 60 T1a patients, applying the ELS protocols for cordectomy classification and voice assessment. Pre- and postoperative voice function analysis included: Vocal Extent Measure (VEM), Dysphonia Severity Index (DSI), auditory-perceptual assessment (GRB), and 9-item Voice Handicap Index (VHI-9i). Altogether, 51 subjects (43 male, eight female, mean age 65 years) completed the study. The 5-year recurrence-free, overall, and disease-specific survival rates (Kaplan–Meier method) were 71.4%, 94.4%, and 100.0%. Voice function was preserved; the objective parameter VEM (64 ± 33 vs. 83 ± 31; mean ± SD) and subjective vocal measures (G: 1.9 ± 0.7 vs. 1.3 ± 0.7; VHI-9i: 18 ± 8 vs. 9 ± 9) even improved significantly (<i>p </i><<i> </i>0.001). The VEM best reflected self-perceived voice impairment. It represents a sensitive measure of voice function for quantification of vocal performance.