2018 Section 6 - Laryngology, Voice Disorders, and Bronchoesophalogy

Reprinted by permission of Laryngoscope. 2016; 126(9):2079‐2084.

The Laryngoscope V C 2015 The American Laryngological, Rhinological and Otological Society, Inc.

Systematic Review

Can Videostroboscopy Predict Early Glottic Cancer? A Systematic Review and Meta-analysis

Camilla S. Mehlum, MD; Tine Rosenberg, MSc; Aagot M. Groentved, MD; Anne-Kirstine Dyrvig, MSc; Christian Godballe, MD, PhD

Objective: Correct assessment of patients with a glottic lesion is crucial for ensuring proper treatment in cases of cancer or premalignancy and for avoiding unnecessary surgery. For years, videostroboscopy (VS) has been the gold standard for assessing such lesions, but diagnostic difficulties have been described. We aim to estimate the diagnostic accuracy of VS in differentiating early glottic cancer from noninvasive lesions by conducting a systematic review and meta-analysis of published studies. Data Sources: PubMed and Embase databases were searched without restrictions on publication date. Review Methods: A systematic review and subsequent meta-analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. We systematically searched the literature for publica- tions on stroboscopic diagnosis of cancer or premalignant lesions on the vocal cords. All retrieved studies were reviewed and qualitatively assessed. The pooled sensitivity and specificity of VS were calculated, and bubble and summary receiver operat- ing characteristics plots were created. Results: A meta-analysis was conducted on five studies with a total of 307 patients. The sensitivities of VS within the single studies ranged from 86% to 100% and specificities ranged from 7% to 93%. The meta-analysis showed that the sensi- tivity of the combined results was 0.96 (95% confidence interval [CI]: 0.89-0.98), and the specificity was 0.65 (95% CI: 0.21- 0.93). Conclusion: VS is able to identify almost all patients with cancer, but only approximately two-thirds of patients with noninvasive lesions are correctly identified as not having cancer. Further research concerning assessment of patients with vocal cord lesions is needed. Key Words: Videostroboscopy, early glottic cancer, vocal cords, cancer, premalignancy, diagnostic accuracy, biopsy, meta- analysis. Level of Evidence: NA Laryngoscope , 126:2079–2084, 2016

INTRODUCTION Almost half of all laryngeal cancers are located in the mucosa of the vocal cords (the glottis). It is well known that the prognosis for patients with cancer is directly related to stage and site of the tumor, and that the mainstay of successful therapy is early and correct diagnosis. Transformation of normal mucosa into premalig- nant lesions (dysplasia or laryngeal intraepithelial neo- Additional Supporting Information may be found in the online ver- sion of this article. From the Department of Otorhinolaryngology–Head and Neck Surgery ( C . S . M ., T . R ., A . M . G ., C . G .); and Centre for Innovative Medical Tech- nology ( A . K . D .), Odense University Hospital, Odense, Denmark The authors have no funding, financial relationships, or conflicts of interest to disclose. Editor’s Note: This Manuscript was accepted for publication September 24, 2015. Send correspondence to Camilla Slot Mehlum, Department of ORL–Head and Neck Surgery, Odense University Hospital, Sdr. Boule- vard 29, DK-5000 Odense C, Denmark. E-mail: camilla.mehlum@rsyd.dk

plasia [LIN]) and invasive cancer is a multistage process. LIN or early cancer often appears as a white or red area in the mucosa of the vocal cords. However, such a lesion may also be absolutely benign (e.g., due to inflammation), in which case the therapeutic approach would be far more conservative. Correct preoperative assessment is therefore of utmost importance, and trustworthy diagnostic methods are strongly needed. For years, videostroboscopy (VS) has been the gold standard for evaluation of glottic lesions, and more stud- ies confirm a considerable diagnostic value. 1–4 VS allows for visualization of the vocal fold vibration, which in real time occurs too fast for the human eye to perceive. It uses a synchronized, flashing light passed through a flexible or rigid telescope. The flashes of light from the stroboscope are synchronized to the vocal fold vibration at a slightly slower speed, and a series of still pictures derived from many successive vibration cycles are merged into a slow-motion video sequence. Normal vocal cords have symmetrical mucosal waves with large ampli- tude. An impaired or absent mucosal wave is found in

DOI: 10.1002/lary.25745

Laryngoscope 126: September 2016

Mehlum et al.: VS and Prediction of Early Glottic Cancer

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