Prostate patients with positive lymph node margins receive an initial course of 45 Gy to the planning target volume (PTV) comprised of prostate, seminal vesicles, and lymph nodes with a 1-cm margin. The prostate is localized via implanted fiducial markers before each fraction is delivered using portal-imaging. However, the pelvic lymph nodes are affixed to the bony anatomy and are not mobile in concert with the prostate. The aim of this study was to determine whether a significant difference in pelvic lymph node coverage exists between planned and delivered external beam therapy treatments for these patients.

中文翻译：

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前列腺聚焦对齐对计划的盆腔淋巴结剂量的影响

具有阳性淋巴结边缘的前列腺患者接受 45 Gy 的初始疗程至由前列腺、精囊和具有 1 厘米边缘的淋巴结组成的计划目标体积 (PTV)。在使用门户成像传送每个部分之前，通过植入的基准标记对前列腺进行定位。然而，盆腔淋巴结附着在骨解剖结构上，不能与前列腺一起移动。本研究的目的是确定为这些患者计划和实施的外照射治疗之间是否存在盆腔淋巴结覆盖率的显着差异。