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

Objectives: To evaluate the results of different treatment modalities for c arcinoma in situ of the glottis, and to identify important prognostic facto rs for outcome. Design: Review of 82 cases treated definitively for glottic carcinoma in si tu between 1958 and 1998. The median follow-up for all patients was 112 mon ths, 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 (grou p 1), 13 with more extensive surgery (group 2) including endoscopic laser r esection (11 patients) and hemilaryngectomy (2 patients), and 54 with radio therapy (group 3). Thirty patients had anterior commissure involvement and 9 had bilateral vocal cord involvement. Radiotherapy was delivered via oppo sed lateral fields at 1.5 to 2.4 Gy per fraction per day (median fraction s ize, 2 Gy), 5 days per week. The median total dose was 64 Gy, and the media n overall time was 47 days. Main Outcome Measures: Initial locoregional control (LRC), ultimate LRC, an d 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. U nivariate analysis showed that the difference in initial LRC rates between groups 1 and 3 was statistically significant (P=.02), although it was not s tatistically significant on multivariate analysis (P=.07). Anterior commiss ure involvement was an important prognostic factor for LRC on both univaria te (P=.03) and multivariate (P=.04; hazard ratio, 1.6) analysis, and its in fluence 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 un ivariate analysis. All but 2 patients in whom treatment failed underwent su ccessful 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 ulti mate LRC and comparable larynx preservation rates. Anterior commissure invo lvement was associated with poorer initial LRC and larynx preservation, par ticularly in the surgically treated patients. The choice of initial treatme nt should be individualized, depending on patient age, reliability, and tum or extent. Pretreatment and posttreatment objective evaluation of voice qua lity should be helpful in determining the best therapy for these patients.