TA26-Technology in Use at The University of Texas M. D. Anderson Cancer Center
Almon S. Shiu, Ph.D.
Associate Professor
Department of Radiation Physics,
The University of Texas M. D. Anderson Cancer Center,
Houston, TX,
The current external-beam treatment technology used at the Division of Radiation Oncology, at the University of Texas M. D. Anderson Cancer Center is the main focus for this section’s presentation. The Division of Radiation Oncology at UTMDACC is the largest single radiation treatment facility in the world. The treatment facilities consist of fourteen linear accelerators, one isocentric Cobalt-60 tele-therapy unit, one 50 KVp and one 250 KVp x-ray therapy units, three CT-simulators and one conventional simulator, more than 50 treatment planning workstations, the QA dosimetry labs and mold room, manual and remote Brachytherapy units, machine shop, and multiple computer resources. Six linear accelerators and one cone-beam CT simulator will be delivered in July, 2004 to our new facility site, Ambulatory Clinic building (across street from our main facilities). In addition, a dedicated image-guided treatment delivery unit will also be delivered to the main facilities in July. At the main campus, we are currently treating more than 400 external-beam patients per day. More than 95% of all external-beam cases are planned based on CT images. The MRI images and PET/CT images are also used in some of the anatomic sites for target and critical structures delineation. Currently, about 35% of our patients have received IMRT (Intensity Modulated Radiotherapy) treatment. The most of the remaining patients are treated with 3D conformal technique except a few palliative treatments delivered with a single or the opposed fields approach. The step and shoot IMRT technique for the brain, head and neck (H&N), and prostate tumors will be discussed and the filed-in-field technique used for H&N and breast treatment will also be discussed. The advantages and disadvantages of the current technology versus the conventional treatment will be evaluated. The respiratory gating for acquired Thoracic CT images and treatment delivery will be presented. In addition, the 4D CT images used to determine the internal target volume (ITV) will be addressed. The current practice of intracranial and extracranial stereotactic radiosurgery and radiotherapy will also be presented. One of the major benefits of the current technology is the reduction of the acute side effects in H&N, breast and prostate. This also allows the radiation oncologists to prescribe a higher target dose and spare the critical structures, which should lead to better tumor control and the increase of survival rate.
TA26－The University of Texas M. D. Anderson Cancer Center使用的放疗技术
Almon S. Shiu, Ph.D
Associate Professor
Department of Radiation Physics,
The University of Texas M. D. Anderson Cancer Center,
Houston, TX,
本报告将主要介绍University of Texas M. D. Anderson Cancer Center放射肿瘤科目前使用的外照射放射治疗技术。UTMDACC放射肿瘤科是目前世界上最大的放射治疗中心。该中心目前拥有的机器设备包括14台直线加速器、1台60Co外照射治疗机、1台50 KVp和1台250 KVp的X线治疗机、3台CT模拟机和1台常规X线模拟机、50多个治疗计划系统工作站、质量保证剂量实验室、模室、手动和后装近距离治疗机、加工车间和大量的计算机资源。在2004年7月将有另外6台直线加速器和1台锥形束CT模拟机到货，并将安装在新的场地－门诊大楼（在主楼的街对面）。另外，在7月份专用的影像引导的治疗机也将到货，并将安装在主楼。在中心总部，每天外照射治疗400多例病人。95%以上接受外照射的病例使用基于CT图像的治疗计划。对于某些解剖部位，为了正确勾画靶区和关键结构，我们也使用MRI图像和PET/CT融合图像。目前，大约35%的病人接受调强放射治疗（IMRT）。另外，除了少数姑息治疗的病人使用单野或对穿野照射外，剩下的大部分病人将接受三维适形放射治疗。本报告将讨论脑肿瘤、头颈部肿瘤和前列腺癌的静态调强放射治疗技术，另外也将讨论头颈部肿瘤和乳腺癌的野中野技术。同时将评估目前技术和常规治疗技术的优缺点。本报告也将讲述CT图像采集和治疗实施时的呼吸门控技术。同时还会探讨如何使用4D CT图像来确定内靶区（ITV）。本报告还将讲述目前使用的颅内、颅外立体定向放射外科和立体定向放射治疗技术。目前使用技术的一个主要优点是减小头颈部肿瘤、乳腺癌和前列腺癌治疗时的急性副作用。这样，放射肿瘤学家可以给予靶区更高的剂量，同时保护关键结构，从而获得更好的肿瘤控制率、提高患者的生存率。