ACRF Image X Institute, University of Sydney, Sydney, Australia.
ACRF Image X Institute, University of Sydney, Sydney, Australia; Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, Australia.
Int J Radiat Oncol Biol Phys. 2018 Jun 1;101(2):387-395. doi: 10.1016/j.ijrobp.2018.01.098. Epub 2018 Feb 6.
To report on the primary and secondary outcomes of a prospective clinical trial of electromagnetic-guided multileaf collimator (MLC) tracking radiation therapy for prostate cancer.
Twenty-eight men with prostate cancer were treated with electromagnetic-guided MLC tracking with volumetric modulated arc therapy. A total of 858 fractions were delivered, with the dose per fraction ranging from 2 to 13.75 Gy. The primary outcome was feasibility, with success determined if >95% of fractions were successfully delivered. The secondary outcomes were (1) the improvement in beam-target geometric alignment, (2) the improvement in dosimetric coverage of the prostate and avoidance of critical structures, and (3) no acute grade ≥3 genitourinary or gastrointestinal toxicity.
All 858 planned fractions were successfully delivered with MLC tracking, demonstrating the primary outcome of feasibility (P < .001). MLC tracking improved the beam-target geometric alignment from 1.4 to 0.90 mm (root-mean-square error). MLC tracking improved the dosimetric coverage of the prostate and reduced the daily variation in dose to critical structures. No acute grade ≥3 genitourinary or gastrointestinal toxicity was observed.
Electromagnetic-guided MLC tracking radiation therapy for prostate cancer is feasible. The patients received improved geometric targeting and delivered dose distributions that were closer to those planned than they would have received without electromagnetic-guided MLC tracking. No significant acute toxicity was observed.
报告一项前瞻性临床试验的主要和次要结果，该试验采用电磁引导多叶准直器（MLC）跟踪放射治疗前列腺癌。
28 例前列腺癌患者接受了电磁引导 MLC 跟踪容积调强弧形治疗。共进行了 858 次分次治疗，每次剂量从 2 到 13.75Gy 不等。主要结果是可行性，成功的标准是如果超过 95%的分次治疗成功完成。次要结果是（1）改善光束-靶标几何对准，（2）改善前列腺的剂量覆盖并避免关键结构，以及（3）无急性≥3 级泌尿生殖或胃肠道毒性。
所有 858 次计划的分次治疗都成功地完成了 MLC 跟踪，证明了可行性的主要结果（P<.001）。MLC 跟踪将光束-靶标几何对准从 1.4 毫米提高到 0.90 毫米（均方根误差）。MLC 跟踪改善了前列腺的剂量覆盖，并减少了对关键结构的每日剂量变化。未观察到急性≥3 级泌尿生殖或胃肠道毒性。
前列腺癌的电磁引导 MLC 跟踪放射治疗是可行的。与没有电磁引导 MLC 跟踪的情况下相比，患者接受了更好的几何定位和更接近计划的剂量分布，且没有明显的急性毒性。
