Abstract：
OBJECTIVE: External beam radiation therapy to the prostate is typically delivered after verification of prostatic position with image guidance. Prostate motion can occur during the delivery of each radiation treatment between the time of localization imaging and completion of treatment. The objective of this work is to review the literature on intrafraction motion (IFM) of the prostate during radiation therapy and offer clinical recommendations on management.
METHODS: A comprehensive literature review was conducted on prostate motion during prostate cancer radiation therapy. Information was organized around 3 key clinical questions, followed by an evidence-based recommendation.
RESULTS: IFM of the prostate during radiation therapy is typically ≤3 mm and is unlikely to compromise prostate dosimetry to a clinically meaningful degree for men treated in a relatively short treatment duration with planning target volume (PTV) margins of ≥3 to 5 mm. IFM of 5 mm or more has been observed in up to ∼10% of treatment fractions, with limited dosimetric effect related to the infrequency of occurrence and longer fractionation of therapy. IFM can be monitored in continuous or discontinuous fashion with a variety of imaging platforms. Correction of IFM may have the greatest value when tighter PTV margins are desired (such as with stereotactic body radiation therapy or intraprostatic nodule boosting), ultrahypofractionated courses, or when treatment time exceeds several minutes.
CONCLUSIONS: This focused review summarizes literature and provides practical recommendations regarding IFM in the treatment of prostate cancer with external beam radiation therapy.
METHODS: A comprehensive literature review was conducted on prostate motion during prostate cancer radiation therapy. Information was organized around 3 key clinical questions, followed by an evidence-based recommendation.
RESULTS: IFM of the prostate during radiation therapy is typically ≤3 mm and is unlikely to compromise prostate dosimetry to a clinically meaningful degree for men treated in a relatively short treatment duration with planning target volume (PTV) margins of ≥3 to 5 mm. IFM of 5 mm or more has been observed in up to ∼10% of treatment fractions, with limited dosimetric effect related to the infrequency of occurrence and longer fractionation of therapy. IFM can be monitored in continuous or discontinuous fashion with a variety of imaging platforms. Correction of IFM may have the greatest value when tighter PTV margins are desired (such as with stereotactic body radiation therapy or intraprostatic nodule boosting), ultrahypofractionated courses, or when treatment time exceeds several minutes.
CONCLUSIONS: This focused review summarizes literature and provides practical recommendations regarding IFM in the treatment of prostate cancer with external beam radiation therapy.
摘要：
目的：通常在图像引导下验证前列腺位置后，对前列腺进行外部束放射治疗。前列腺运动可以在每次放射治疗的递送期间在定位成像的时间和完成治疗的时间之间发生。这项工作的目的是回顾有关放射治疗期间前列腺的内部运动（IFM）的文献，并提供临床管理建议。
方法：对前列腺癌放射治疗期间的前列腺运动进行了全面的文献综述。围绕三个关键临床问题组织了信息，其次是基于证据的建议。
结果：放射治疗期间前列腺的IFM通常≤3mm，对于在相对较短的治疗时间内治疗且计划目标体积（PTV）边缘≥3-5mm的男性，不太可能将前列腺剂量测定降低到有临床意义的程度。在高达10%的治疗部分中观察到5毫米或更大的IFM，具有有限的剂量学影响，与发生频率低和治疗分割时间长有关。可以用各种成像平台以连续或不连续的方式监测IFM。当需要更紧密的PTV边缘时（例如使用立体定向身体放射治疗或前列腺内结节增强），IFM的校正可能具有最大的价值。超小分割课程，或治疗时间超过几分钟。
结论：本综述总结了文献，并提供了关于IFM在外照射治疗前列腺癌方面的实用建议。
方法：对前列腺癌放射治疗期间的前列腺运动进行了全面的文献综述。围绕三个关键临床问题组织了信息，其次是基于证据的建议。
结果：放射治疗期间前列腺的IFM通常≤3mm，对于在相对较短的治疗时间内治疗且计划目标体积（PTV）边缘≥3-5mm的男性，不太可能将前列腺剂量测定降低到有临床意义的程度。在高达10%的治疗部分中观察到5毫米或更大的IFM，具有有限的剂量学影响，与发生频率低和治疗分割时间长有关。可以用各种成像平台以连续或不连续的方式监测IFM。当需要更紧密的PTV边缘时（例如使用立体定向身体放射治疗或前列腺内结节增强），IFM的校正可能具有最大的价值。超小分割课程，或治疗时间超过几分钟。
结论：本综述总结了文献，并提供了关于IFM在外照射治疗前列腺癌方面的实用建议。
