Treatment results of carcinoma in situ of the glottis: An analysis of 82 cases

Objectives: To evaluate the results of different treatment modalities for carcinoma in situ of the glottis, and to identify important prognostic factors for outcome. Design: Review of 82 cases treated definitively for glottic carcinoma in situ between 1958 and 1998. The median follow-up for all patients was 112 months, and 90% had more than 2 years of follow-up. Setting: Academic tertiary care referral centers. Intervention: Fifteen patients were treated with vocal cord stripping (group 1), 13 with more extensive surgery (group 2) including endoscopic laser resection (11 patients) and hemilaryngectomy (2 patients), and 54 with radiotherapy (group 3). Thirty patients had anterior commissure involvement and 9 had bilateral vocal cord involvement. Radiotherapy was delivered via opposed lateral fields at 1.5 to 2.4 Gy per fraction per day (median fraction size, 2 Gy), 5 days per week. The median total dose was 64 Gy, and the median overall time was 47 days. Main Outcome Measures: Initial locoregional control (LRC), ultimate LRC, and larynx preservation. Results: The 10-year initial LRC rates were 56% for group 1, 71% for group 2, and 79% for group 3. Of those who failed, the median time to relapse was 11 months for group 1, 17 months for group 2, and 41 months for group 3. Univariate analysis showed that the difference in initial LRC rates between groups 1 and 3 was statistically significant (P=.02), although it was not statistically significant on multivariate analysis (P=.07). Anterior commissure involvement was an important prognostic factor for LRC on both univariate (P=.03) and multivariate (P=.04; hazard ratio, 1.6) analysis, and its influence appeared to be mainly confined to the surgically treated patients (groups 1 and 2). The 10-year larynx preservation rates were 92% for group 1, 70% for group 2, and 85% for group 3. Anterior commissure involvement was the only important prognostic factor for larynx preservation (P=.01) on univariate analysis. All but 2 patients in whom treatment failed underwent successful salvage surgery. Voice quality was deemed good to excellent in 73% of the patients in group 1,40% in group 2, and 68% in group 3. Conclusions: Treatment of carcinoma in situ of the glottis with vocal cord stripping or more extensive surgery or radiotherapy provided excellent ultimate LRC and comparable larynx preservation rates. Anterior commissure involvement was associated with poorer initial LRC and larynx preservation, particularly in the surgically treated patients. The choice of initial treatment should be individualized, depending on patient age, reliability, and tumor extent. Pretreatment and posttreatment objective evaluation of voice quality should be helpful in determining the best therapy for these patients.