Medical Radiation Science (MRS), School of Health Sciences, The University of Newcastle, Callaghan, New South Wales, Australia.
Liverpool and Macarthur Cancer Therapy Centres, South West Sydney Local Health District, Liverpool, New South Wales, Australia.
J Med Radiat Sci. 2021 Dec;68(4):379-388. doi: 10.1002/jmrs.529. Epub 2021 Jul 19.
Chemoradiotherapy (CRT) is the standard treatment for locally advanced cervical and vaginal cancer. It is associated with high haematological toxicity (HT) that can lead to treatment interruptions and cancelled chemotherapy cycles, reducing the potential effectiveness of this regimen. Bone marrow sparing (BMS) utilising volumetric modulated arc therapy (VMAT) is one method to reduce dose to the active bone marrow (ABM) so that HT rates are reduced. The aim of this paper was to assess whether BMS-VMAT can effectively spare the ABM whilst maintaining clinically acceptable target and organ-at-risk (OAR) doses.
Twenty gynaecological cancer patients treated with definitive CRT at the Liverpool/Macarthur Cancer Therapy centres between 2015 and 2020 were retrospectively included. ABM was delineated based on fluorodeoxyglucose positron emission tomography (FDG-PET) imaging. Weekly blood tests and ABM dose parameters at the V10Gy, V20Gy, V30Gy, V40Gy and Dmean were assessed on original plans for any potential correlation with grade 2+ HT. Replanned with VMAT for BMS, various dose parameters were compared with the original plan to assess for any significant differences.
Active bone marrow doses were significantly reduced (P < 0.001 for all parameters) in BMS-VMAT plans, and significant improvements in target and OAR coverage were found compared with the original plans. Compared with VMAT only, target and OARs were comparable. No significant correlations between HT and ABM doses were found.
Bone marrow sparing volumetric modulated arc therapy can significantly reduce dose to the active bone marrow whilst maintaining acceptable target and OAR doses. Future prospective trials are needed to evaluate the clinical impact of BMS on toxicity and compliance.
化学放疗(CRT)是局部晚期宫颈癌和阴道癌的标准治疗方法。它与高血液学毒性(HT)相关,可能导致治疗中断和取消化疗周期,降低该方案的潜在疗效。利用容积调强弧形治疗(VMAT)进行骨髓保护(BMS)是减少活性骨髓(ABM)剂量的一种方法,从而降低 HT 发生率。本文旨在评估 BMS-VMAT 是否可以在保持临床可接受的靶区和危及器官(OAR)剂量的同时,有效地保护 ABM。
回顾性纳入 2015 年至 2020 年间在利物浦/麦克阿瑟癌症治疗中心接受根治性 CRT 治疗的 20 例妇科癌症患者。根据氟脱氧葡萄糖正电子发射断层扫描(FDG-PET)成像对 ABM 进行描绘。评估原始计划中每周血液检查和 ABM 剂量参数 V10Gy、V20Gy、V30Gy、V40Gy 和 Dmean,以评估其与 2+级 HT 的潜在相关性。采用 VMAT 进行 BMS 再计划,比较原始计划与再计划的各种剂量参数,以评估是否存在显著差异。
BMS-VMAT 计划中 ABM 剂量显著降低(所有参数 P<0.001),与原始计划相比,靶区和 OAR 覆盖率显著提高。与仅 VMAT 相比,靶区和 OAR 相当。未发现 HT 与 ABM 剂量之间存在显著相关性。
骨髓保护容积调强弧形治疗可显著降低 ABM 剂量,同时保持可接受的靶区和 OAR 剂量。需要前瞻性试验来评估 BMS 对毒性和依从性的临床影响。