Yu E, Shenouda G, Beaudet M P, Black M J
London Regional Cancer Centre, Ontario, Canada.
Int J Radiat Oncol Biol Phys. 1997 Feb 1;37(3):587-91. doi: 10.1016/s0360-3016(96)00578-0.
Different radiotherapy fractionation schedules were used over a 10-year period to treat patients with early squamous cell carcinoma of the vocal cords at McGill University. A retrospective analysis was performed to study the effect of fraction size on local control in this group of patients.
A total of 126 previously untreated patients with T1 invasive squamous cell carcinoma of the true vocal cords were irradiated between January 1978 and December 1988 in the Department of Radiation Oncology at McGill University. All patients received megavoltage irradiation, 94 patients received daily fractions > 2 Gy (64 patients received 50 Gy with once-daily 2.5-Gy fractions, and 30 received 65.25 Gy in 29 fractions of 2.25 Gy each), and 32 patients were treated to a dose of 66 Gy in 33 fractions with 2 Gy/fraction. Patients' characteristics of prognostic importance were equally distributed between the two fractionation groups.
At a median follow-up of 84 months, the 10-year disease-free survival and overall survival were 76% and 93%, respectively. Local control for patients treated with > 2 Gy fraction was 84%, compared to 65.6% for those treated with 2-Gy fractions (p = 0.026). Among the prognostic factors tested, such as gender, age, stage, anterior and posterior commissure involvement, smoking history, and fraction size, the latter was the only significant predictor of local control for the whole group of patients in univariate (p = 0.041) and multivariate (p = 0.023) analysis. There was no observed difference in the incidence of complications between the two fractionation groups.
From the results of this retrospective review of patients treated with radiotherapy for T1 true vocal cord cancer, and within the range of total doses and overall treatment times used in our patients, it was found that fractionation schedules using daily fraction size > 2 Gy are associated with a better local control than schedules delivering 2 Gy/fraction, with no increase in toxicity.
在10年期间，麦吉尔大学采用了不同的放射治疗分割方案来治疗早期声带鳞状细胞癌患者。进行了一项回顾性分析，以研究分割剂量大小对该组患者局部控制的影响。
1978年1月至1988年12月期间，麦吉尔大学放射肿瘤学系共对126例未经治疗的T1期真性声带浸润性鳞状细胞癌患者进行了放射治疗。所有患者均接受兆伏级放疗，94例患者每日分割剂量>2 Gy（64例患者接受2.5 Gy每日一次的分割剂量，共50 Gy；30例患者接受2.25 Gy的分割剂量，共29次，总剂量65.25 Gy），32例患者接受2 Gy/次的分割剂量，共33次，总剂量66 Gy。两组患者中，具有预后意义的患者特征分布均衡。
中位随访84个月时，10年无病生存率和总生存率分别为76%和93%。分割剂量>2 Gy的患者局部控制率为84%，而分割剂量为2 Gy的患者局部控制率为65.6%（p = 0.026）。在测试的预后因素中，如性别、年龄、分期、前后联合受累情况、吸烟史和分割剂量大小，分割剂量大小是单因素分析（p = 0.041）和多因素分析（p = 0.023）中整个患者组局部控制的唯一显著预测因素。两组分割方案的并发症发生率无差异。
从对T1期真性声带癌患者放疗的回顾性研究结果来看，在我们患者使用的总剂量和总治疗时间范围内，发现每日分割剂量>2 Gy的分割方案比2 Gy/次的分割方案局部控制效果更好，且毒性未增加。
