de Jong J S, van Diest P J, Baak J P
Department of Pathology, Free University Hospital, Amsterdam, The Netherlands.
Lab Invest. 1995 Dec;73(6):922-6.
Microvessel counting has proven to be of prognostic value in breast cancer, as shown in different retrospective studies. However, methodology has not been studied widely, and this must be done before the method can become clinically applicable. The aim of this study was to determine the degree of heterogeneity and reproducibility of microvessel counts (MC) in breast cancer.
In 10 cases of breast cancer, the available blocks (2-4 blocks) containing invasive tumor parts were selected, and four sections (4 microns) were cut with interdistances of 100 microns. In each section, two or three invasive areas (0.5 x 0.5 cm) were demarcated. Microvessels, visualized by immunohistochemistry (CD31 Ab), were counted by one observer in 10 systematically selected fields of vision (400 x magnification). Furthermore, microvessels were counted in four fields with the highest microvessel density ("hot spots"). Coefficients of variation (CV) were calculated for the different sampling levels.
Repeated MC yielded high intra- and interobserver reproducibility (correlation coefficients > 0.92). For the systematic counting method, CV between MC from different areas within one section was on average (17.1% (0.7-52.1). When comparing MC from corresponding areas in different sections from the same black, CV was on average 14.7% (0.5-41.9), and for MC from different blocks of the same tumor, CV was on average 25.8% (9.9-44.6). Nested ANOVA showed an approximately equal contribution to the total variance of the different sampling levels, except for the variation between sections (not significant). For the hot spot MC, CV for different sections from the same block was on average 11.1% (0.7-29.5) and for different blocks from the same tumor, 24.2% (5.7-54.9). Nested ANOVA showed that variation between different blocks from the same tumor contributed most to the total variance.
There is a noteworthy heterogeneity in MC between different areas from the same section, between corresponding areas in different sections from the same block, and between different blocks from the same tumor. Consequently, one must carefully scan all the available tumor material in each case for the best hot spot. The hot spot approach is efficient and reproducible, but only a comparative prognostic evaluation can show whether it is clinically more useful than systematic counts.
如不同的回顾性研究所示，微血管计数已被证明在乳腺癌中具有预后价值。然而，该方法尚未得到广泛研究，在其能够临床应用之前必须进行此项研究。本研究的目的是确定乳腺癌中微血管计数（MC）的异质性程度和可重复性。
在10例乳腺癌病例中，选取包含浸润性肿瘤部分的可用组织块（2 - 4个组织块），切成间距为100微米的四张4微米厚的切片。在每张切片中，划定两到三个浸润区域（0.5×0.5厘米）。通过免疫组织化学（CD31抗体）显示的微血管由一名观察者在10个系统选择的视野（400倍放大）中进行计数。此外，在四个微血管密度最高的区域（“热点”）进行微血管计数。计算不同采样水平的变异系数（CV）。
重复进行的微血管计数显示观察者内和观察者间具有高度可重复性（相关系数>0.92）。对于系统计数方法，同一切片内不同区域的微血管计数之间的CV平均为17.1%（0.7 - 52.1）。当比较同一组织块不同切片中相应区域的微血管计数时，CV平均为14.7%（0.5 - 41.9），对于同一肿瘤不同组织块的微血管计数，CV平均为25.8%（9.9 - 44.6）。嵌套方差分析显示，除切片间变异（不显著）外，不同采样水平对总方差的贡献大致相等。对于热点微血管计数，同一组织块不同切片的CV平均为11.1%（0.7 - 29.5），同一肿瘤不同组织块的CV为24.2%（5.7 - 54.9）。嵌套方差分析显示，同一肿瘤不同组织块间的变异对总方差的贡献最大。
在同一切片的不同区域、同一组织块不同切片的相应区域以及同一肿瘤的不同组织块之间，微血管计数存在显著的异质性。因此，对于每个病例，必须仔细扫描所有可用的肿瘤组织以寻找最佳热点。热点方法高效且可重复，但只有通过比较预后评估才能表明它在临床上是否比系统计数更有用。
