Muren Ludvig Paul, Wasbø Ellen, Helle Svein Inge, Hysing Liv Bolstad, Karlsdottir Asa, Odland Odd Harald, Valen Harald, Ekerold Randi, Johannessen Dag Clement
Department of Oncology and Medical Physics, Haukeland University Hospital, Bergen, Norway.
Int J Radiat Oncol Biol Phys. 2008 Jul 15;71(4):1034-41. doi: 10.1016/j.ijrobp.2007.11.060. Epub 2008 Feb 4.
We present planning and early clinical outcomes of a study of intensity-modulated radiotherapy (IMRT) for locally advanced prostate cancer.
A total of 43 patients initially treated with an IMRT plan delivering 50 Gy to the prostate, seminal vesicles, and pelvic lymph nodes, followed by a conformal radiotherapy (CRT) plan delivering 20 Gy to the prostate and seminal vesicles, were studied. Dose-volume histogram (DVH) data for the added plans were compared with dose-volume histogram data for the sum of two CRT plans for 15 cases. Gastrointestinal (GI) and genitourinary (GU) toxicity, based on the Radiation Therapy Oncology Group scoring system, was recorded weekly throughout treatment as well as 3 to 18 months after treatment and are presented.
Treatment with IMRT both reduced normal tissue doses and increased the minimum target doses. Intestine volumes receiving more than 40 and 50 Gy were significantly reduced (e.g., at 50 Gy, from 81 to 19 cm(3); p = 0.026), as were bladder volumes above 40, 50, and 60 Gy, rectum volumes above 30, 50, and 60 Gy, and hip joint muscle volumes above 20, 30, and 40 Gy. During treatment, Grade 2 GI toxicity was reported by 12 of 43 patients (28%), and Grade 2 to 4 GU toxicity was also observed among 12 patients (28%). With 6 to 18 months of follow-up, 2 patients (5%) experienced Grade 2 GI effects and 7 patients (16%) experienced Grade 2 GU effects.
Use of IMRT for pelvic irradiation in prostate cancer reduces normal tissue doses, improves target coverage, and has a promising toxicity profile.
我们展示了一项针对局部晚期前列腺癌的调强放射治疗（IMRT）研究的计划制定及早期临床结果。
共研究了43例患者，这些患者最初接受了一个IMRT计划，该计划向前列腺、精囊和盆腔淋巴结给予50 Gy的剂量，随后接受一个适形放射治疗（CRT）计划，该计划向前列腺和精囊给予20 Gy的剂量。将添加计划的剂量体积直方图（DVH）数据与15例患者两个CRT计划总和的剂量体积直方图数据进行比较。基于放射治疗肿瘤学组评分系统，在整个治疗过程中每周记录胃肠道（GI）和泌尿生殖系统（GU）毒性，以及治疗后3至18个月的毒性情况并予以呈现。
IMRT治疗既降低了正常组织剂量，又提高了最小靶区剂量。接受超过40 Gy和50 Gy照射的肠道体积显著减少（例如，在50 Gy时，从81 cm³降至19 cm³；p = 0.026），接受超过40 Gy、50 Gy和60 Gy照射的膀胱体积、接受超过30 Gy、50 Gy和6 Gy照射的直肠体积以及接受超过20 Gy、30 Gy和40 Gy照射的髋关节肌肉体积也显著减少。在治疗期间，43例患者中有12例（28%）报告出现2级GI毒性，12例患者（28%）也观察到2至4级GU毒性。随访6至18个月时，2例患者（5%）出现2级GI效应，7例患者（16%）出现2级GU效应。
在前列腺癌盆腔照射中使用IMRT可降低正常组织剂量，改善靶区覆盖情况，且毒性特征良好。
