A method including edge effects for the estimation of radioimmunotherapy absorbed doses in the tumor xenograft model.
A method including edge effects for the estimation of radioimmunotherapy absorbed doses in the tumor xenograft model.
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一种包括边缘效应的方法，用于估计肿瘤异种移植模型中放射免疫治疗吸收剂量。
DOI：
10.1118/1.597377
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发表时间：
1994
期刊：
影响因子：
3.8
通讯作者：
Wanek,PM
中科院分区：
文献类型：
--
作者：
Buras,R;Williams,LE;Beatty,BG;Wong,JY;Beatty,JD;Wanek,PM
在裸鼠人结肠癌异种移植模型（LS 174 T）中，评价了放射性标记单克隆抗体（Mab）摄取与肿瘤大小的时间关系，以帮助开发放射免疫治疗吸收剂量估计方法。用4.4 MBq（120 μCi）90 Y标记的抗癌胚抗原单克隆抗体（90 Y-ZCE 025）治疗大小不均匀的肿瘤。回归分析表明，在四个时间间隔（N>10点/间隔）：12-24 h，2-3 d，5-7 d和10-14 d，抗体摄取（%ID/g）与肿瘤质量呈对数-对数反比关系。预测放射性核素浓度与时间的曲线，然后构建一系列恒定的肿瘤大小。通过对每条曲线进行时间积分并应用适当的剂量估算公式获得异种移植物辐射剂量。对于每个假设的肿瘤块，假设球形肿瘤形状，对靶体积外的β能量损失进行边缘校正。对于肿瘤大小变化20倍（分别为0.1-2.0 g），估计的平均吸收剂量仅在13.8-10.3戈伊之间变化。这种恒定的剂量可以解释我们小组在早期实验中观察到的异种移植物停滞，在这个水平的管理90 Y活动。
The temporal relationship of radiolabeled monoclonal antibody (Mab) uptake to tumor size in a nude mouse human colon cancer xenograft model (LS174T) was evaluated as an aid to developing a method for estimation of radioimmunotherapy absorbed dose. Tumors of heterogeneous size were treated with 4.4 MBq (120 μCi) of90Y‐labeled anti‐Carcinoembryonic Antigen Mab (90Y‐ZCE025). Regression analysis demonstrated an inverse log–log relationship of antibody uptake (%ID/g) to tumor mass in four time intervals investigated (N>10 points/interval):12–24 h, 2–3 d, 5–7 d, and 10–14 d. Curves of predicted radionuclide concentration vs time were then constructed for a range of constant tumor sizes. Xenograft radiation dose was obtained by temporal integration of each curve and application of appropriate dose estimation formulas. For each assumed tumor mass, an edge correction for loss of beta energy outside the target volume was applied assuming a spherical tumor shape. Estimated average absorbed doses were found to vary only from 13.8–10.3 Gy for a 20‐fold change in tumor sizes (0.1–2.0 g, respectively). Such constancy of dose may explain xenograft stasis observed by our group in earlier experiments at this level of administered90Y activity.