CBCT和超声技术在HIFU与IMRT联合治疗胰腺癌中的应用价值

目的 探讨千伏级锥形束CT（CBCT）与超声技术在高强度聚焦超声（HIFU）联合调强放疗（IMRT）治疗胰腺癌中的应用价值。方法 2010年12月至2012年6月收治的21例胰腺癌患者均采用HIFU联合IMRT治疗模式。应用超声多普勒评估治疗情况，调整HIFU治疗剂量和治疗次数；CBCT引导下行IMRT，2 Gy／次，5次／周，6～7周，DT 58～70Gy。分析IMRT在CBCT引导后的摆位误差及PTV外扩边界。评价患者治疗前、后的疼痛缓解情况和KPS评分。结果 本组21例患者共实施6～18次HIFU治疗。IMRT在CBCT引导后平均误差小于2 mm。21例患者中疼痛完全缓解12例，部分缓解8例，无效1例，总有效率为95.0％。无1例发生严重并发症。治疗前KPS评分为 （46.8±9.1）分，治疗后为（87.1±8.3）分，差异有统计学意义（P＜0.01）。全组3例患者死亡，平均生存期10个月。结论 将CBCT图像引导技术与超声技术应用于HIFU联合IMRT治疗胰腺癌，能有效降低危及器官的受照射量，增强肿瘤的局部控制，减少并发症，提高患者的生存质量。

Application of CBCT and ultrasound technology in HIFU combined with IMRT for pancreatic cancer

Objective To investigate the application of cone-beam computed tomography （CBCT） and ultrasonic technology guided high intensity focused ultrasound （HIFU） combined with intensity modulated radiation therapy （IMRT） for pancreatic cancer. Methods The method of HIFU combined IMRT was used on 21 pancreatic cancer patients collected from December 2010 to June 2012. The treatment effect of HIFU was assessed through the doppler ultrasound, the treatment doses and times of next fraction were regulated according to patient tolerance, the tumor and its blood supply. CBCT guided IMRT was executed with a total dose from 58Gy to 70Gy, and 2Gy at one time, 5 fractions a week, lasting for 6-7 weeks. The setup error and PTV boundary after CBCT guided IMRT were analyzed. The pain relief effect and KPS score were evaluated. Results The total fractions of HIFU were 6-18. The IMRT treat- ment precision was less than 2mm on average with CBCT guiding. Twelve patients＇ pain all alleviated completely; 8 patients＇ pain alle- viated partially and 1 case was invalid. There was no serious complication occurred with a total efficacy of 95.0% in 21 patients. The KPS score of patients before treatment was 46. 8 ± 9. 1, which was lower than that after treatment （ 87.1 ± 8.3 ）, showing significant differences （P 〈 0.05 ）. Three patients died, and the average survival time was 10 months. Conclusion With a substantial increase in treatment precision, the combination of HIFU and IMRT enhanced the tumor control ability, deceases the dose of organs at risk to a safe value, and the complications are reduced with improved living quality of patients.