Mahzouni Parvin, Mohammadizadeh Fereshteh, Mougouei Kourosh, Moghaddam Noushin Afshar, Chehrei Ali, Mesbah Alireza
Department of Pathology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
Indian J Pathol Microbiol. 2010 Oct-Dec;53(4):605-10. doi: 10.4103/0377-4929.71996.
Astrocytic brain tumors are the most common primary central nervous system tumors, which are classified into four grades. One of the most important pathologic criteria for the diagnosis of higher-grade astrocytomas (especially glioblastoma multiforme) is microvessel proliferation, particularly in the form of glomeruloid complex. Because tumor angiogenesis is a necessary factor for growth and invasiveness of malignancies, microvessel density (MVD) and intensity of angiogenesis may be used to determine the grade of astrocytomas and plan therapy accordingly. We have planned this study to evaluate the relationship between vwf expression in microvessels and different grades of astrocytoma.
Sixty-four formalin-fixed and paraffin-embedded blocks of surgical specimens with diagnosis of astrocytoma (grades I to IV, each of them 16 blocks) were selected in a simple-nonrandom sampling. Thin sections of tissue blocks underwent immunohistochemical staining for vwf. The stained slides were examined using a light microscope at low (100) and high (400) magnifications. MVD was estimated by calculating the mean number of stained microvessels in three areas of highest vascularization in the high-power field (400). The intensity of staining was determined based on a 3 scale model, in which scores 0, 1, 2, and 3 mean no detectable stain, trace staining, moderate amount of diffuse stain, and strong diffuse staining, respectively.
Thirty-six (56%) patients were male and 28 (44%) were female. Scores 0 and 1 of microvessel staining intensity were not observed in any grades studied, but severe staining intensity (score 3) was observed in 18.8%, 37.5%, 56.3%, and 87.5% of grades I, II, III, and IV astrocytomas, respectively. "Vwf vessel index" (MVD staining intensity of microvessels) was 23.84, 25.62, 31.62, and 62.43 in grades I, II, III, and IV astrocytomas, respectively.
We found a significant relationship between staining intensity of vwf in microvessels and different grades of astrocytomas. The intensity of microvessel stain increases in parallel with increasing tumor grade. Regarding "microvessel density" and "vwf vessel index," the difference is predominantly between grade IV and all other grades. However, there is no other statistically meaningful difference between grades I, II and III.
星形细胞脑肿瘤是最常见的原发性中枢神经系统肿瘤，分为四个级别。诊断高级别星形细胞瘤（尤其是多形性胶质母细胞瘤）最重要的病理标准之一是微血管增殖，特别是肾小球样复合体形式。由于肿瘤血管生成是恶性肿瘤生长和侵袭的必要因素，微血管密度（MVD）和血管生成强度可用于确定星形细胞瘤的级别并据此制定治疗方案。我们计划开展本研究以评估微血管中vwf表达与不同级别的星形细胞瘤之间的关系。
采用简单非随机抽样法，选取64个诊断为星形细胞瘤的手术标本的福尔马林固定石蜡包埋块（I至IV级，各16块）。组织块薄片进行vwf免疫组织化学染色。使用光学显微镜在低倍（100）和高倍（400）放大倍数下检查染色玻片。通过计算高倍视野（400）中血管化程度最高的三个区域中染色微血管的平均数来估计MVD。根据一个三级模型确定染色强度，其中0、1、2和3分分别表示未检测到染色、微量染色、中等量弥漫性染色和强弥漫性染色。
36例（56%）患者为男性，28例（44%）为女性。在所研究的任何级别中均未观察到微血管染色强度为0和1分的情况，但在I、II、III和IV级星形细胞瘤中，分别有18.8%、37.5%、56.3%和87.5%观察到强染色强度（3分）。I、II、III和IV级星形细胞瘤的“vwf血管指数”（微血管的MVD染色强度）分别为23.84、25.62、31.62和62.43。
我们发现微血管中vwf的染色强度与不同级别的星形细胞瘤之间存在显著关系。微血管染色强度随肿瘤级别升高而平行增加。关于“微血管密度”和“vwf血管指数”，差异主要存在于IV级与所有其他级别之间。然而，I、II和III级之间没有其他具有统计学意义的差异。
