Department of Radiation Oncology, Osaka University Graduate School of Medicine, Osaka, Japan.
Department of Radiation Oncology, Osaka General Medical Center, Osaka, Japan.
Acta Oncol. 2021 May;60(5):582-588. doi: 10.1080/0284186X.2020.1865563. Epub 2021 Jan 6.
Previous studies reported that cigarette smoking during radiation therapy was associated with unfavorable outcomes in various cancers using medical interviewing or monitoring of cotinine. Here, we evaluated the effect of smoking cessation on definitive radiation therapy for early stage glottic carcinoma by monitoring expiratory carbon monoxide (CO).
We enrolled 103 patients with early glottic carcinoma (T1N0/T2N0 = 79/24) who underwent conventional radiotherapy between 2005 and 2016. The median age was 70 years. Pathologically, all patients had squamous cell carcinoma. Since 2009, we confirmed smoking cessation before radiation therapy by medical interviews. Since 2014, we measured expiratory CO to strictly monitor smoking cessation. The patients were divided according to diagnosis years: 'no cessation' (2005-2008), 'incomplete cessation' (2009-2013), and 'complete cessation' (2014-2016). We retrospectively analyzed the local recurrence rate and disease-free survival (DFS).
The median follow-up period was 60.1 months (range, 1.9-110.0 months). The 2-year local recurrence rate in the 'complete cessation' group was 5.3% and tended to be lower than that in the 'incomplete cessation' group (13.7%) and 'no cessation' group (21.2%). Multivariate analysis revealed that 'no cessation' was a risk factor for DFS (hazard ratio [HR] = 4.25) and local recurrence rate (HR = 16.5, < .05) compared to 'complete cessation.'
We confirmed that the 'complete cessation' group had better prognosis than the 'no cessation' group by monitoring expiratory CO during radiation therapy for early stage glottic carcinoma. Moreover, monitoring expiratory CO was easier and more suitable than conventional methods for evaluating smoking cessation because it provided real-time measurements.
之前的研究报告指出，在各种癌症的放射治疗期间吸烟，通过医学访谈或可替宁监测与不良结果相关。在这里，我们通过监测呼气一氧化碳（CO）来评估戒烟对早期声门型喉癌根治性放疗的影响。
我们招募了 103 名接受常规放疗的早期声门型喉癌（T1N0/T2N0=79/24）患者，这些患者均在 2005 年至 2016 年间接受了治疗。中位年龄为 70 岁。所有患者均为鳞状细胞癌。自 2009 年以来，我们通过医学访谈确认放射治疗前的戒烟情况。自 2014 年以来，我们通过测量呼气 CO 来严格监测戒烟情况。根据诊断年份，将患者分为“未戒烟”（2005-2008 年）、“不完全戒烟”（2009-2013 年）和“完全戒烟”（2014-2016 年）三组。我们回顾性分析了局部复发率和无病生存率（DFS）。
中位随访时间为 60.1 个月（范围为 1.9-110.0 个月）。“完全戒烟”组的 2 年局部复发率为 5.3%，且低于“不完全戒烟”组（13.7%）和“未戒烟”组（21.2%）。多因素分析显示，与“完全戒烟”组相比，“未戒烟”是 DFS（风险比[HR]=4.25）和局部复发率（HR=16.5，<.05）的危险因素。
我们通过监测早期声门型喉癌放射治疗期间的呼气 CO，证实了“完全戒烟”组的预后优于“未戒烟”组。此外，与传统方法相比，监测呼气 CO 更简单、更适合评估戒烟情况，因为它提供了实时测量结果。
