Research Center Hospital for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-city, Chiba 263-8555, Japan.
J Radiat Res. 2013 Jul 1;54(4):684-9. doi: 10.1093/jrr/rrs134. Epub 2013 Jan 7.
This study was carried out to evaluate the influence of fraction size 2.25 Gy on local control of T1 and T2 laryngeal and hypopharyngeal cancers. Between August 2002 and December 2010, 80 patients with T1 and T2 laryngeal or hypopharyngeal cancers were treated with definitive radiotherapy with a fraction size of 2.25 Gy. Primary sites were the larynx in 69 and the hypopharynx in 11. Fifty-three patients were T1 and 27 were T2. All patients' pathology was squamous cell carcinoma except one carcinosarcoma. Radiotherapy was delivered 5 days/week with a 4-MV photon beam up to a total dose of 63.0 Gy. Median treatment time was 41 days. Statistical analysis of survival was calculated using the Kaplan-Meier method. No acute toxicity greater than grade 2 (CTCAE ver. 3.0.) including mucositis and dermatitis was observed. All but one patient had a complete response. The partial response patient received salvage surgery. The median follow-up period was 47 months (ranging from 4 to 108 months). No late toxicity greater than 1 was observed. Nine patients developed recurrence, seven local and two neck lymph nodes. Three patients died, one from laryngeal cancer and two from intercurrent diseases. The 5-year local control rates (LCRs) in the entire group, larynx T1, larynx T2 and hypopharynx T1 were 85.8%, 97.6%, 70.1% and 85.7%, respectively. The LCRs of T1 improved compared with our historical control, but not those of T2. The 2.25-Gy fraction size is safe and may have the potential to achieve good LCR in T1 lesions.
这项研究旨在评估 2.25Gy 分割剂量对 T1 和 T2 喉和下咽癌局部控制的影响。2002 年 8 月至 2010 年 12 月，80 例 T1 和 T2 喉和下咽癌患者接受了 2.25Gy 分割剂量的根治性放疗。原发部位为 69 例喉和 11 例下咽。53 例为 T1，27 例为 T2。除 1 例癌肉瘤外，所有患者的病理均为鳞状细胞癌。放疗采用 4MV 光子束，每周 5 天，总剂量 63.0Gy。中位治疗时间为 41 天。采用 Kaplan-Meier 法进行生存统计分析。未观察到大于 2 级（CTCAE ver.3.0）的急性毒性，包括黏膜炎和皮炎。除 1 例部分缓解患者外，所有患者均获得完全缓解。该部分缓解患者接受了挽救性手术。中位随访时间为 47 个月（4 至 108 个月）。未观察到大于 1 级的晚期毒性。9 例患者复发，7 例局部复发，2 例颈部淋巴结转移。3 例患者死亡，1 例死于喉癌，2 例死于并发疾病。全组、喉 T1、喉 T2 和下咽 T1 的 5 年局部控制率（LCR）分别为 85.8%、97.6%、70.1%和 85.7%。T1 的 LCR 较我们的历史对照有所改善，但 T2 的 LCR 没有改善。2.25Gy 分割剂量是安全的，有可能实现 T1 病变的良好 LCR。
