Merfeld Emily C, Kuczmarska-Haas Aleksandra, Burr Adam R, Witt Jacob S, Francis David M, Ntambi Jayne-Norah, Desai Vimal K, Huang Jessie Y, Miller Jessica R, Lawless Michael J, Wallace Charles R, Anderson Bethany M, Bradley Kristin A
Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI.
Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI.
Brachytherapy. 2022 Nov-Dec;21(6):792-798. doi: 10.1016/j.brachy.2022.07.006. Epub 2022 Aug 24.
We aimed to determine the relationship between gross tumor volume (GTV) dose and tumor control in women with medically inoperable endometrial cancer, and to demonstrate the feasibility of targeting a GTV-focused volume using imaged-guided brachytherapy.
An endometrial cancer database was used to identify patients. Treatment plans were reviewed to determine doses to GTV, clinical target volume (CTV), and OARs. Uterine recurrence-free survival was evaluated as a function of CTV and GTV doses. Brachytherapy was replanned with a goal of GTV D98 EQD ≥ 80 Gy, without regard for coverage of the uninvolved uterus and while respecting OAR dose constraints.
Fifty-four patients were identified. In the delivered plans, GTV D90 EQD ≥ 80 Gy was achieved in 36 (81.8%) patients. Uterine recurrence-free survival was 100% in patients with GTV D90 EQD ≥ 80 Gy and 66.7% in patients with EQD < 80 Gy (p = 0.001). On GTV-only replans, GTV D98 EQD ≥ 80 Gy was achieved in 39 (88.6%) patients. Mean D was lower for bladder (47.1 Gy vs. 73.0 Gy, p < 0.001), and sigmoid (47.0 Gy vs. 58.0 Gy, p = 0.007) on GTV-only replans compared to delivered plans. Bladder D was ≥ 80 Gy in 11 (25.0%) delivered plans and four (9.1%) GTV-only replans (p = 0.043). Sigmoid D was ≥ 65 Gy in 20 (45.4%) delivered plans and 10 (22.7%) GTV-only replans (p = 0.021).
OAR dose constraints should be prioritized over CTV coverage if GTV coverage is sufficient. Prospective evaluation of image-guided brachytherapy to a reduced, GTV-focused volume is warranted.
我们旨在确定无法进行手术治疗的子宫内膜癌女性患者的肿瘤总体积（GTV）剂量与肿瘤控制之间的关系，并证明使用影像引导近距离放疗靶向以GTV为重点的靶区体积的可行性。
使用子宫内膜癌数据库来识别患者。审查治疗计划以确定给予GTV、临床靶区体积（CTV）和危及器官（OAR）的剂量。评估子宫无复发生存率与CTV和GTV剂量的关系。重新制定近距离放疗计划，目标是GTV D98等效剂量（EQD）≥80 Gy，不考虑未受累子宫的覆盖情况，同时遵守OAR剂量限制。
共识别出54例患者。在已实施的计划中，36例（81.8%）患者实现了GTV D90 EQD≥80 Gy。GTV D90 EQD≥80 Gy的患者子宫无复发生存率为100%，EQD<80 Gy的患者为66.7%（p = 0.001）。仅针对GTV重新制定计划时，39例（88.6%）患者实现了GTV D98 EQD≥80 Gy。与已实施的计划相比，但仅针对GTV重新制定计划时，膀胱的平均剂量较低（47.1 Gy对73.0 Gy，p<0.001），乙状结肠的平均剂量也较低（47.0 Gy对58.0 Gy，p = 0.007）。在已实施的计划中，11例（25.0%）患者膀胱剂量≥80 Gy，在仅针对GTV重新制定的计划中有4例（9.1%）患者膀胱剂量≥80 Gy（p = 0.043）。在已实施的计划中，20例（45.4%）患者乙状结肠剂量≥65 Gy，在仅针对GTV重新制定的计划中有10例（22.7%）患者乙状结肠剂量≥65 Gy（p = 0.021）。
如果GTV覆盖充分，应优先考虑OAR剂量限制而非CTV覆盖。有必要对影像引导近距离放疗至缩小的、以GTV为重点的靶区体积进行前瞻性评估。
