Treatment of Early-Stage Glottic Cancer: Meta-analysis Comparison of Laser Excision versus Radiotherapy

Objectives: The primary objective of this study was to conduct a meta-analysis to compare the oncologic outcomes of external radiation (XRT) and transoral laser (TOL) surgical excision in the treatment of early-stage glottic cancer. The secondary outcome examined was posttreatment voice quality. Design: Meta-analysis. Method: Systematic methods were used to identify published and unpublished data. Two reviewers screened all titles and abstracts for relevance and independently assessed all articles. All identified studies were retrospective. Main Outcome Measures: Local control, overall survival, laryngectomy-free survival, and posttreatment voice quality. Results: For oncologic control, case series were pooled as a composite group using a random effects model. The analysis was based on over 7600 patients. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. There were no significant differences between TOL surgery and XRT for local control (OR 0.81, 95% CI 0.51-1.3) and laryngectomy-free survival (OR 0.73, 95% CI 0.39-1.35). For overall survival, the analysis favoured TOL surgery (OR 1.48, 95% CI 1.19-1.85). For voice quality, there were no objective differences; however, there was a trend toward superiority for XRT. Conclusions: This is the first study to examine the management of early glottic cancer using meta-analytic methodology. The analysis shows that although there is a trend favouring TOL surgery for overall survival, there is no clear difference in oncologic outcome between TOL surgery and XRT. However, there is a trend toward improved posttreatment voice quality with XRT. This is of questionable clinical significance as objective voice analyses often do not correlate with subjective assessments.