Bauer J, Gries W, Bahmer F A
Universitäts-Hautklinik, Homburg/Saar, Bremen, Germany.
Pathol Res Pract. 1995 Dec;191(12):1192-7. doi: 10.1016/S0344-0338(11)81125-8.
Multicellular tumour-spheroids are regarded as suitable models for cancer research, similar to avascular tumour parts. As a size parameter of the spheroids, usually their maximum diameter is used, estimated on a section presumed to be equatorial or near equatorial. Estimation of the volume of spheroids is of interest for the detection of subtle changes in different kinds of investigations. Since spheroids are often not truly spherical, and because model-based methods for volume determination may be biased, Cavalieri's principle, rediscovered recently for stereology, was used to determine the volume of the spheroids. Here we report the results of the volume estimation of colon carcinoma spheroids, together with an outline of the basic stereological principle and formulas used. The spheroids investigated had a volume between 1.4 and 92.3 mm3 (mean 33.9). The volume fraction of necrotic to viable tissue cells was between 0.6:1 and 2.2:1. The coefficient of error (CE) was remarkably low with 3.7% for the volumes. Both inter- and intraobserver-variability were extremely low with correlation coefficients (r2) of 99%. Thus, the high precision of the stereological method, combined with a low workload, make it ideally suitable for routine volume estimation.
多细胞肿瘤球体被视为癌症研究的合适模型，类似于无血管的肿瘤部分。作为球体的一个尺寸参数，通常使用其最大直径，该直径在假定为赤道或接近赤道的切片上进行估计。在各种研究中，对球体体积的估计对于检测细微变化很有意义。由于球体通常并非真正的球形，而且基于模型的体积测定方法可能存在偏差，因此最近重新发现的用于体视学的卡瓦列里原理被用于确定球体的体积。在此，我们报告结肠癌球体体积估计的结果，以及所使用的基本体视学原理和公式的概述。所研究的球体体积在1.4至92.3立方毫米之间（平均为33.9）。坏死组织细胞与存活组织细胞的体积分数在0.6:1至2.2:1之间。体积的误差系数（CE）非常低，为3.7%。观察者间和观察者内的变异性都极低，相关系数（r2）为99%。因此，体视学方法的高精度与低工作量相结合，使其非常适合常规体积估计。
