Kouloulias Vassilis E, Giraud Jean-Yves, Davis Bernard J, Dusserre Andrée, Zurlo Alfredo, Bolla Michel
EORTC, DATA CENTER, Av. Mounier 83, B-1200, Brussels, Belgium.
Radiother Oncol. 2004 Oct;73(1):11-20. doi: 10.1016/j.radonc.2004.08.005.
The EORTC trial 22961, opened in 1997, was designed to investigate the optimal combination of hormonal adjuvant treatment by LHRH analogue and radiation therapy for the management of locally advanced prostate cancer. A dummy run was established to assess centre compliance to the radiotherapy protocol.
Medical and anatomical data obtained from 37 CT slices (5mm thickness) of an eligible patient were sent to 19 participating centres, which were asked to complete a questionnaire according to their practice and plan a theoretical radiotherapy treatment. The Planning Target Volume 1 (PTV1) should include prostate, seminal vesicles, internal iliac lymph nodes and inferior part of common iliac lymph nodes (extended pelvic fields). Centres which usually irradiate with small pelvic fields (N0 patients), were allowed to include the prostate, seminal vesicles and internal iliac lymph nodes plus a safety margin of 2 cm. For the Planning Target Volume 2 (PTV2), a safety margin of 1.5 to 2 cm should be around the prostate and seminal vesicles. Checks included patient positioning, treatment simulation, target volume definition, treatment set-up and clinical controls during treatment.
Eleven institutions with actual 81% of patients' accrual in the protocol have responded. All centres used a supine treatment position and positioning lasers for the set-up, while 73 and 45% of the centres performed cystograms and used rectal contrast, respectively. Among the participating centres, 45% and 55% used blocks and MLC, respectively, to treat patients. Extended pelvic fields in terms of PTV1 were used by 63% of the centres. The remaining centres treated a small PTV1 with a 10-20 mm margin around to CTV1. All centres defined PTV2 according to protocol guidelines. Doses to PTV1 and PTV2 were correctly prescribed. It was difficult to assess the treated volumes due to a lack of standardisation in DVH calculations.
In general, centres participating in the dummy run adhered to the guidelines. The dummy run enhances the reliability of the conclusions of the trial.
1997年开展的欧洲癌症研究与治疗组织（EORTC）试验22961旨在研究促性腺激素释放激素（LHRH）类似物激素辅助治疗与放射治疗相结合用于局部晚期前列腺癌治疗的最佳组合。设立了一次预试验以评估各中心对放疗方案的依从性。
从一名符合条件患者的37层CT扫描图像（层厚5毫米）中获取的医学和解剖学数据被发送至19个参与中心，要求这些中心根据其实际操作完成一份问卷并规划一次理论放疗治疗。计划靶体积1（PTV1）应包括前列腺、精囊、髂内淋巴结和髂总淋巴结下部（扩大盆腔野）。通常采用小盆腔野放疗（N0患者）的中心，允许将前列腺、精囊和髂内淋巴结纳入，并加上2厘米的安全边界。对于计划靶体积2（PTV2），应在前列腺和精囊周围设置1.5至2厘米的安全边界。检查内容包括患者定位、治疗模拟、靶体积定义、治疗摆位以及治疗期间的临床对照。
11家机构做出了回应，这些机构实际纳入了方案中81%的患者。所有中心均采用仰卧位治疗体位并使用定位激光进行摆位，分别有73%和45%的中心进行了膀胱造影和使用了直肠造影剂。在参与中心中，分别有45%和55%的中心使用挡铅和多叶准直器（MLC）来治疗患者。63%的中心采用了PTV1定义的扩大盆腔野。其余中心对较小的PTV1进行治疗，在临床靶体积1（CTV1）周围设置10至20毫米的边界。所有中心均按照方案指南定义PTV2。对PTV1和PTV进行了正确的剂量处方。由于剂量体积直方图（DVH）计算缺乏标准化，难以评估治疗体积。
总体而言，参与预试验的中心遵守了指南。预试验提高了试验结论的可靠性。
