Voice and Treatment Outcome from Phonosurgical Management of Early Glottic Cancer

Abstract

Phonosurgical management of early glottic cancer has evolved considerably, but objective vocal outcome data are sparse. A prospective clinical trial was done on 32 patients with unilateral cancer (T1a in 28 and T2a in 4) who underwent ultranarrow-margin resection; 15 had resection superficial to the vocal ligament, and 17 deep to it. The subepithelial infusion technique facilitated selection of these patients for the appropriate procedure. All are cancer-free without radiotherapy or open surgery. Involvement of the anterior commissure (22/32) or the vocal process (15/32) of the arytenoid cartilage did not influence local control. Nine of 17 patients had resection of paraglottic musculature, and all underwent medialization reconstruction by lipoinjection and/or Gore-Tex laryngoplasty. Eight of the 17 had resections deep to the vocal ligament, but without vocalis muscle, and 1 of the 8 underwent medialization. Posttreatment vocal function measures were obtained for all patients. A clear majority of the patients displayed normal values for average fundamental frequency (72%) during connected speech, and normal noise-to-harmonics ratio (75%) and average glottal airflow (91%) measures during sustained vowels. Smaller majorities of patients displayed normal values for average sound pressure level (SPL; 59%) during connected speech and for maximum ranges for fundamental frequency (56%) and SPL (59%). Fewer than half of the patients displayed normal values for sustained vowel measures of jitter (45%), shimmer (22%), and maximum phonation time (34%). Almost all patients had elevated subglottal pressures and reduced values for the ratio of SPL to subglottal pressure (vocal efficiency). There were significant improvements in a majority of patients for most vocal function measures after medialization reconstruction. Normal or near-normal conversation-level voices were achieved in most cases, regardless of the disease depth, by utilization of a spectrum of resection and reconstruction options. These favorable results are based on establishing aerodynamic glottal competency and preserving the layered microstructure of noncancerous glottal tissue.