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Is There a Change in the Treatment of T1 Glottic Cancer After CO
Uygar Levent Demir1, Turgut Çevik1, Fikret Kasapoğlu1
1Department of Otorhinolaryngology, Uludağ University School of Medicine, Bursa, Turkey.
Objective:
Carbon dioxide (CO2) laser provides high local control and disease-specific survival rates with minor morbidity and good quality of life in transoral cordectomy. We aimed to compare the oncological outcome and survival between cold steel and CO2 laser in the treatment of early glottic cancer.
Methods:
In this retrospective study, the participants were divided into two groups. The first group comprised patients who were operated upon between 2001 and 2007 using cold steel (group 1, n=38), and the second group comprised patients who were operated upon between 2008 and 2016 using CO2 laser (group 2, n=88). Both groups were compared regarding age, gender, pathological grade, T stage, type of cordectomy, margin status, anterior commissure involvement, follow-up, locoregional recurrence, and disease-free survival (DFS).
Results:
The overall survival rate and DFS were similar between the two groups (94.7% vs. 98.9% and 100% vs. 98.9%, respectively), and no association was found between surgical margin positivity and local recurrence. However, a significant association between the presence of anterior commissure involvement and recurrence was found in all 126 patients (p=0.016). Local recurrence was significantly higher in the group 2 (p=0.024), but it did not affect overall survival and DFS in these patients (100% vs. 94.1%).
Conclusion:
Although CO2 laser excision is considered to be superior to cold steel regarding surgical time and bleeding control, the local recurrence rates were found to be higher with the laser than the cold steel. Thus, we argue that cases should be selected more carefully concerning the anterior commissure, depth of tumor invasion lateral to vocal muscle, difficulty at endoscopic exposure for lesions with anterior commissure involvement, and reliability of surgical margins at frozen sections.
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