Objective: To evaluate the safety and efficacy of helical tomotherapy using simultaneously integrated boost and simultaneous integrated protection technique in the treatment of unresectable biliary tract cancers. Methods: The data of 23 patients with unresectable biliary tract cancer who received tomotherapy-based hypofractionated radiotherapy at Comprehensive Cancer Centre of Drum Tower Hospital,the Affiliated Drum Tower Clinical College of Nanjing Medical University between February 2015 and October 2017 were analyzed. There were 10 males and 13 females, aged from 40 to 85 years(median:58 years). Pathological type included intrahepatic cholangiocarcinomas(n=11), gallbladder cancers(n=6),extrahepatic cholangiocarcinomas(n=6). The irradiated sites covered primary tumors and areas of local invasion,including metastatic lymph nodes which were confined to the abdominal or retroperitoneal space. Dose escalation was achieved using simultaneously integrated boost(SIB) technique, and simultaneous integrated protection(SIP)technique was used to protect gastrointestinal tracts and other adjacent organs. Cox regression modal and Kaplan-Meier analysis were used to analyze the associations between patients' characteristics and overall survival(OS). Results: The median total radiation dose was 54 Gy(range: 28-72 Gy)and median biologically effective dose(BED)was 74.4 Gy(range: 37.8-115.2 Gy).The median planning target volume(PTV)was 445.79 cm(3)(range:126.02-950.12 cm(3)). Based on the various PTV,patients received 2.4-6.0 Gy/fraction with 8-28 fractions. The local control rate was 65.2% and the median OS was 11.3 months(range:2.1-31.9 months).The most common cause of death was out-field failure and only 3 patients died of in-field failures. The longest survival was 31.9 months. BED≥70 Gy significantly improved OS,compared to BED<70 Gy(16.8 months vs.5.1 months)(HR=0.146, 95%CI:0.028-0.762, P=0.022). No patients developed grade ≥4 toxicities. Conclusions: Helical tomotherapy-based hypofractionated radiotherapy is effective and well tolerated for patients with unresectable biliary tract cancer. The dose escalation with higher BED could improve the survival for such patients.
目的： 探讨基于螺旋断层放疗系统采用同步加量和同步保护技术治疗不可切除胆道癌患者的安全性与效果。 方法： 回顾性分析2015年2月至2017年10月在南京大学医学院附属鼓楼医院肿瘤中心接受螺旋断层放疗的23例无法切除的非远处转移胆道癌患者的临床资料。男性10例，女性13例，中位年龄为58岁（范围：40~85岁）。肝内胆管癌11例，肝外胆管癌6例，胆囊癌6例。照射范围为肝内肿瘤和周围受累区域，包括局限于腹腔或腹膜后的转移性淋巴结等肿瘤灶。采用同步加量/同步保护技术实现大分割照射，提高肿瘤区生物效应剂量，同时减少周围危及器官的剂量。采用Cox回归模型和Kaplan-Meier生存分析研究患者特征与总体生存时间之间的关联。 结果： 放疗的中位处方剂量为54 Gy（范围：28~72 Gy），中位生物效应剂量为74.4 Gy（范围：37.8~115.2 Gy），中位计划靶体积为445.79 cm(3)（范围：126.02~950.12 cm(3)）。由于靶区部位与范围不同，患者接受的分割剂量为2.4~6.0 Gy，分次数为8~28次。局部控制率为65.2%（15/23），中位生存时间为11.3个月（范围：2.1~31.9个月）。生物效应剂量≥70 Gy的患者生存时间高于生物效应剂量<70 Gy的患者（16.8个月比5.1个月，HR=0.146，95%CI：0.028~0.762，P=0.022）。3例患者出现3级不良反应，未见≥4级的不良反应。 结论： 同步加量/同步保护螺旋断层放疗技术对于范围较大的不可切除胆道癌患者初步效果明确，耐受良好，较高的BED可以延长患者的生存时间。.
Keywords: Biliary tract neoplasms; Hypofractionated radiotherapy; Radiotherapy, computer-assisted.