ObjectivesTo investigate the most important factors affecting the prognosis of the patients with squamous cell carcinoma (SCC) of the larynx.MethodsBased on the clinical and follow-up data, 205 patients with SCC of the larynx receiving total laryngectomy, partial laryngectomy, or CO2 laser surgery in GuangDong General Hospital were retrospectively analyzed. A survival analysis was performed by the Kaplan-Meier method and a multivariable analysis of prognostic factors was carried out using the Cox proportional hazard model.ResultsSubtypes of carcinoma included 69.8% glottic and 30.2% supraglottic. Most patients were in N0 stage (77.6%), and 22.4% patients were in N1∼N3 stage. Over half of the patients were in T1∼T2 stage (55.1%), 20.0% in T3, and 24.9% in T4. Mean follow-up duration was 49.2 months. The survival rates 1, 2, and 3 years after the surgery were 99.0%, 91.7%, and 81.5%, respectively. The survival rate for those patients with clinical stage IV was significantly lower than for those with clinical stage I and II (p<0.001 and p = 0.013, respectively). The disease-free progression rates 1, 2, and 3 years after the surgery were 83.9%, 74.6%, and 71.2%, respectively. Futhermore, those patients with a Charlson score of 1 to 2 and ≥3 had higher risk of mortality than those with a Charlson score of 0 (hazard ratios of 1.8 and 2.41 p = 0.042 and p = 0.008). Multivariable analysis revealed that clinical stage, surgical margin, and comorbidity were significantly associated with both mortality and disease-free progression.ConclusionThe surgical resection margin, clinical stage, and comorbidity were independent factors affecting the laryngeal cancer prognosis. The survival rates were lower for patients with advanced laryngeal cancer, positive surgical margins, or severe comorbidity, suggesting the importance of early diagnosis, early treatment, negative surgical margins, and conditions of comorbidity.

Objectives-An in-vivo rabbit model was used to study the effect of three hours of experimental induced phonation on messenger RNA expression of the normal vocal fold.Study Design-Prospective; animal model. Subjects and Methods-Ten rabbits received experimental phonation for three hours, followed by one hour of recovery. A separate group of five rabbits served as no-phonation controls. We measured messenger RNA expression of matrix metalloproteinase -1, -9, and interleukin-1β using real-time reverse transcribed polymerase chain reaction. Gene expression ratios from phonation and control animals were compared using the Mann Whitney U test.Results-Phonation (77 +/− 3 dB; 429 +/−141 Hz) resulted in increased matrix metalloproteinase -1 gene expression from rabbits receiving experimental phonation compared to controls, and a non-significant increase in matrix metalloproteinase -9 and interleukin-1β gene expression. Conclusion-Matrix metalloproteinases play a role in maintaining tissue homeostasis.Investigation of cellular responses to experimental phonation may provide insight into how matrix metalloproteinases and other extracellular matrices contribute to maintenance of the vocal fold and development of pathology.

Objectives/Hypothesis Our laboratory has developed an in vivo rabbit model to investigate the effects of phonation on expression and turnover of the vocal fold extracellular matrix. As a logical outgrowth of this research to include phonotrauma in the present study, we investigated the hypothesis that an increase in airflow rate delivered to the glottis produces a change in glottal configuration and an increase in mean phonation intensity. Study Design Prospective animal study. Methods Six New Zealand white breeder rabbits weighing 3 to 5 kg were used in this study. A rigid endoscope and camera were used to document glottal configuration. Acoustic signals of modal and raised phonation were recorded and digitized. Two separate one-way repeated measures analysis of variance (ANOVA) tests were used to investigate within subject differences in phonation intensity and fundamental frequency between modal and raised phonation. Results Phonation intensity was 54.19 dB SPL (6.21 standard deviations [SD]) during modal phonation, and 60.31 dB SPL (5.68 SD) during raised phonation. Endoscopic images revealed a convergent glottis, with greater separation of the vocal folds during raised phonation. Results of ANOVA revealed a significant within subjects effect for phonation intensity (P = .011). Pairwise comparisons revealed that phonation intensity increased significantly during raised phonation, compared to modal phonation (P = .008). No differences in mean fundamental frequency were observed between phonation conditions. Conclusions Improved understanding of factors that control phonation output in the in vivo rabbit model will result in improved capabilities to match phonation dose across animals and provide immediate direction to future biochemical studies.

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