Department of Radiotherapy and Oncology, 60200Ghent University Hospital, Ghent, Belgium.
Department of Human structure and Repair, 26656Ghent University, Ghent, Belgium.
Technol Cancer Res Treat. 2023 Jan-Dec;22:15330338231154088. doi: 10.1177/15330338231154088.
The aim is to evaluate the incidental dose to the lymphatic regions in prostate-only radiotherapy (PORT) and to compare hematological outcome between PORT and whole pelvic radiotherapy (WPRT) in node-positive prostate cancer (pN1 PCa), in the era of modern radiotherapy techniques. We performed a prospective phase 3 trial in which a total of 64 pN1 PCa patients were randomized between PORT (ARM A) and WPRT (ARM B) delivered with volumetric-modulated arc therapy (VMAT). The lymph node (LN) regions were delineated separately and differences between groups were calculated using Welch -tests. Hematological toxicity was scored according to common terminology criteria for adverse events (CTCAE) version 4.03. To evaluate differences in the evolution of red blood cell (RBC), white blood cell (WBC), and platelet count over time between PORT and WPRT, 3 linear mixed models with a random intercept for the patient was fit with model terms randomization group, study time point, and the interaction between both categorical predictors. Except for dose to the obturator region, the incidental dose to the surrounding LN areas was low in ARM A. None of the patients developed severe hematological toxicity. The change in RBC from time point pre-external beam radiotherapy (EBRT) to month 3 and for WBC from time point pre-EBRT to months 3 and 12 was significantly different with ARM B showing a larger decrease. The incidental dose to the lymphatic areas becomes neglectable when PORT is delivered with VMAT. Hematological toxicity is very low after WPRT with VMAT and when bone marrow constraints are used for planning, although WPRT causes a decrease in RBC and WBC count over time.
目的是评估前列腺仅放疗（PORT）中淋巴结区域的偶然剂量，并比较现代放疗技术时代中淋巴结阳性前列腺癌（pN1 PCa）中 PORT 和全盆腔放疗（WPRT）的血液学结果。我们进行了一项前瞻性 3 期试验，其中共有 64 名 pN1 PCa 患者被随机分为 PORT（ARM A）和 WPRT（ARM B），分别采用容积调强弧形治疗（VMAT）。单独勾画淋巴结（LN）区域，并使用 Welch 检验计算组间差异。根据不良事件常用术语标准（CTCAE）版本 4.03 对血液学毒性进行评分。为了评估 PORT 和 WPRT 之间红细胞（RBC）、白细胞（WBC）和血小板计数随时间的变化差异，我们使用具有患者随机截距的 3 个线性混合模型拟合模型项随机分组、研究时间点以及两个分类预测因子之间的交互作用。除了闭孔区域的剂量外，ARM A 中周围 LN 区域的偶然剂量较低。没有患者发生严重的血液学毒性。从外部束放射治疗（EBRT）前到第 3 个月的 RBC 变化以及从 EBRT 前到第 3 个月和第 12 个月的 WBC 变化，ARM B 显示出更大的下降，这两个变化具有显著差异。当使用 VMAT 进行 PORT 时，淋巴结区域的偶然剂量变得可以忽略不计。尽管 WPRT 会导致 RBC 和 WBC 计数随时间减少，但使用 VMAT 进行 WPRT 时血液学毒性非常低，并且在规划时使用骨髓限制。
