Mean Microvessel Count Research Articles

Prognostic importance of tumor angiogenesis in breast carcinoma with adjuvant chemotherapy.

Tumor angiogenesis is believed to be related to prognostic factors involved in tumor development and metastasis. Using immunohistochemical methods, we evaluated tumor angiogenesis in 42 early invasive breast cancer patients (T1-2, NO-1-2, M0). Four patients received tamoxifen, 25 patients received CAF or CA, and 15 patients received CMF as adjuvant therapy. The median follow-up was 47 (range 24-119) months. Ten patients (43.5%) in the node-positive group and 2 patients (10.5%) in the node-negative group relapsed (p = 0.019). The mean microvessel count (MVC) was 60.3 3.05 per 200x field (range: 16-95). MVCs of postmenopausal and premenopausal patients were 50.13 +/- 5.74 and 68.64 +/- 4.11, respectively, in the axillary lymph node (ALN)-negative patient group (p = 0.04). Staining was moderate to strong in 13 (68%) ALN-negative and in 17 (74%) ALN-positive patients (p > 0.05), and was also moderate to strong in 82% of premenopausal patients and in 50% of postmenopausal patients (p = 0.037). There was no significant relationship between angiogenesis and p53, nor was angiogenesis significantly associated with the patient ER status and tumor size. No significant correlations were found between OS/DFS and Factor VIII staining or p53 (log rank test, p > 0.05). Of all ALN-negative patients with increased angiogenesis, one patient of the CMF group relapsed, but no recurrence occurred in patients undergoing anthracycline-based chemotherapy (p > 0.05). On the other hand, of all ALN-positive patients with increased angiogenesis, 5/14 patients treated with anthracylcine and 2/2 CMF-treated patients relapsed (p = 0.175). Despite the statistical insignificance, anthracycline-based adjuvant chemotherapy appears to be more effective than CMF as regards relapse prevention particularly in early ALN-positive breast cancer patients with increased angiogenesis. Additional studies are necessary to demonstrate the clinical importance of angiogenesis.

Increased angiogenesis and Fas-ligand expression are independent processes in acute myeloid leukemia

We evaluated the clinical significance of tumor angiogenesis and Fas-ligand (FasL) expression using parameters including the microvessel count (MVC), vascular endothelial growth factor (VEGF) level, and FasL expression in patients with acute myeloid leukemia (AML). Paraffin-embedded bone marrow (BM) sections from 43 AML patients at diagnosis, 20 patients after subsequent induction therapy, and 18 controls with non-invasive lymphoma were stained immunohistochemically for von Willebrand factor (vWF) and FasL. VEGF in BM mononuclear cells from 32 AML patients at diagnosis and 10 controls, including bone marrow transplantation donors, was assayed by an ELISA method. We found that the mean MVC, VEGF level, and FasL expression in AML patients at diagnosis were significantly higher than those of controls, with a significant correlation between the MVC and VEGF levels ( r=0.43). However, there were no correlations between FasL expression and MVC or VEGF level. The mean MVC and FasL expression after induction therapy were lower than those evaluated at diagnosis, but were higher than those of controls. There was a correlation between the MVC and percentage of BM blasts ( r=0.479), but no correlation between the MVC, VEGF level, or FasL expression and other hematologic or clinical variables. Our findings provide evidence of increased angiogenesis and tumor immune escape in AML, and both angiogenesis and tumor immune escape are independent processes in AML.

Vascular endothelial growth factor - its relation to neovascularization and their significance as prognostic factors in renal cell carcinoma.

Angiogenesis is a series of processes that include endothelial proliferation, migration and tube formation. Vascular endothelial growth factor (VEGF) is regarded as a potent mediator of angiogenesis, vascular permeability and tumor cell growth in renal cell carcinoma. This study was designed to evaluate the expression of VEGF and the microvessel count (MVC) and to determine their prediction efficacies for prognosis in renal cell carcinoma. The relationship between the expression of VEGF and MVC were evaluated immunohistochemically in 50 patients with renal cell carcinoma who received a radical nephrectomy at Wonju Christian Hospital between 1989 and 1997. Microvessels were identified by immunostaining endothelial cells for CD-31 antigen. The mean follow-up was 96 months (3 - 133 months). Overall 5-year survival rate was 71.5%. VEGF was expressed in the tumor cell cytoplasm. Of the 50 tumors, 23 (46%) were weak to strongly positive for VEGF but 27 (54%) were unreactive. The respective 5-year survival rates for patients with positive and negative expressions of VEGF were 70% and 73% (p > 0.05). The overall mean MVC was 13.4 in a 400x field. Mean MVCs were significantly higher in VEGF-positive tumors (17.6 +/- 12.1) than in VEGF-negative tumors (9.9 +/- 5.4), and the MVCs of the high vascular density group and the low vascular density groups were significantly different. The 5-year survival rates of patients with high vascular density and low vascular density were 59% and 86%. The median survival period for patients with MVCs higher than or equal to 10 vessels/field was 85 months, whereas for those with MVCs lower than 10 vessels/field the median survival time was 102 months. These results suggest that MVC may be a better prognostic factor in renal cell carcinoma than the expression of VEGF.

Expression of three extracellular matrix degradative enzymes in bladder cancer.

The relationship between expression of extracellular matrix degradative enzymes, angiogenesis and survival of multistage bladder cancer was determined. Expression of 3 extracellular matrix degradative enzymes (metalloproteinase-2, -9 and heparanase) and microvessel formation were examined in 40 resected bladder cancer specimens by immunohistostochemic staining, and then the association of the enzyme expression with angiogenesis and various stages of cancer was investigated. Heparanase protein expression in muscular invasive or lymph-node metastatic cancer was significantly higher than in superficial or nonmetastatic cancer, respectively (69% vs. 8%, p < 0.001, and 80% vs. 40%, p = 0.028, respectively). Interestingly, heparanase was expressed at much higher levels than matrix metalloproteinase-2 and -9. The mean microvessel count in cancers with heparanase expression was significantly higher than that in cancers without heparanase expression (32.3 +/- 18.2 vs. 5.5 +/- 6.1, p = 0.0008). The microvessel formation was not associated with the expression of matrix metalloproteinase-2 and -9. The cancer-specific and overall survival rates of patients with heparanase expression were significantly lower than those of patients without it (p = 0.0001 and p = 0.0008, respectively). Multivariate analysis showed that heparanase expression was a significantly independent prognostic factor for both cancer-specific (p = 0.0047) and overall survival (p = 0.0200). Our study suggested that heparanase plays important roles in invasion, angiogenesis and metastasis of bladder cancer, and thus, this molecule could be a new molecule to inhibit invasion, angiogenesis and metastasis of bladder cancer. Moreover, our results indicate that expression of heparanase could be a new prognostic factor of this disease.

Prognostic significance of angiogenesis in non-small cell lung cancer

Background : Angiogenesis plays a critical role in human tumor growth and metastasis. Microvessel count as a measure of tumor angiogenesis, has been significantly correlated with invasive and metastatic patterns in breast. prostate and cutaneous carcinomas. Materials and Methods : Fifty patients with curatively resected non-small cell lung cancer were evaluated. Tumor tissues embedded in paraffin block were stained by anti CD 31 (PECAM, platelet endothelial cellular adhesion molecule) using immunohistochemical method to assess microvessel count. Microvessels were counted in the most active areas of neovascularization(microscopy, 200). Results: 1) Mean microvessel count was 47.117.7(per 200field) in total 50 cases. 2) Mean microvessel count of adenocarcinoma (54.419.9) was significantly higher than that of squamous cancer (43.916.2) (p45, 28 cases) were 46 months, 75% and 12%, respectively. As results, prognosis of low microvascular group is statistically significantly superior to that of the high microvascular group (p=0.0162, Kaplan-Meier, log-rank). Conclusion : Angiogenesis assessed by microvessel count can be used as one of the significant prognostic factors in non-small cell lung cancer.

Prognostic significance and effect of chemoradiotherapy on microvessel density (angiogenesis) in esophageal Barrett's esophagus-associated adenocarcinoma and squamous cell carcinoma

Previous studies have shown that intratumoral microvessel density (IMD) correlates with clinical outcome in a variety of human neoplasms, such as those that arise in the breast, colon, and stomach, suggesting that angiogenesis is important in cancer progression. The aims of this study were to evaluate the prognostic utility of IMD in esophageal Barrett's-associated adenocarcinoma (AdCa) and squamous cell carcinoma (SCC), and to determine the effect of preoperative chemoradiotherapy (chemrad) on this process. Tissue sections of tumor from 67 patients with esophageal carcinoma (45 with Barrett's-associated AdCa, 22 with SCC) were stained with the vascular marker CD31. The IMD was calculated by evaluating at least 5 different 200 × fields of tumor hot spot areas to obtain the mean microvessel count (MVC). The data then were correlated with the clinical and pathological features, chemrad status, and patient survival. The MVC was significantly higher in AdCa (143 ± 63.2) compared with SCC (77.2 ± 38.6, P = 0.0001). In AdCa, no correlation was noted between the MVC and any of the clinical or pathological features, including chemrad status. In contrast, in SCC, a statistically significant higher MVC was detected in patients who did not receive chemrad (97.2 ± 37.3) compared with those who did (48.3 ± 15.9, P = .002) and in tumors that were larger in size ( P = .02). However, the MVC did not correlate with survival in either AdCa or SCC ( P > .05). The degree of angiogenesis is not a significant prognostic indicator in either esophageal AdCa or SCC. Preoperative chemrad has a positive effect on reducing the degree of angiogenesis in esophageal carcinoma, particularly SCC.

The Effect of Medroxyprogesterone Acetate on Angiogenesis in Complex Endometrial Hyperplasia

Objective.To evaluate the effect of orally administered medroxyprogesterone acetate upon angiogenesis in the myometrium of patients with complex endometrial hyperplasia.Methods.Microvessel counts in the myometrium of consecutive patients with complex endometrial hyperplasia, treated with oral medroxyprogesterone acetate prior to hysterectomy (n= 12), were compared with microvessel counts of consecutive control patients with complex endometrial hyperplasia without prehysterectomy medroxyprogesterone acetate treatment (n= 15). All specimens were stained immunohistochemically for factor VIII-related antigen as a sensitive and specific marker for vascular endothelium. Areas with the highest angiogenic intensity, within the myometrium immediately underlying complex endometrial hyperplasia, were selected. Three fields (×400) were selected for each slide, and the mean microvessel count per high-power field was calculated. Statistical analysis included factorial analysis of variance/covariance, and multiple regression analysis withP< 0.05 considered significant throughout.Results.Microvessel counts of uterine specimens of patients with complex endometrial hyperplasia treated with oral medroxyprogesterone acetate were significantly lower than microvessel counts of control patients with complex endometrial hyperplasia without medroxyprogesterone acetate therapy (median 20, range 11–37 versus median 38, range 20–130, respectively,P< 0.001).Conclusion.Orally administered medroxyprogesterone acetate has a significant antiangiogenic effect upon myometrium immediately underlying complex endometrial hyperplasia.

Tumor Angiogenesis in Vulvar Squamous Cell Carcinoma

Objective.Angiogenesis has been shown to correlate positively with the presence of metastatic disease in some tumors, but has not been studied in invasive vulvar squamous cell carcinoma. Fifty cases of invasive vulvar squamous cell carcinoma were studied in an effort to correlate angiogenesis with stage, survival, and pattern of invasion.Methods.These patients were diagnosed between 1987 and 1993. Microvessels were identified immunohistochemically using antibody to Factor VIII, and areas of greatest microvessel density associated with tumor were counted. The pattern of invasion was categorized as “spray,” “pushing,” or “mixed.” The mean microvessel count was correlated with surgical and clinical stage, pattern of invasion, and survival.Results.Mean microvessel counts in surgical stage I/II cases (31.1 ± 7.3) were not significantly different from stage III/IV cases (26.3 ± 8.6) (P= 0.089). Similarly mean microvessel counts in clinical stage I/II cases (31.6 ± 11.9) were not significantly different from stage III/IV cases (27.0 ± 8.7) (P= 0.198). Seventeen patients who died of disease had mean counts of 26.1 ± 6.4, while 21 patients alive with or without evidence of disease had counts of 31.1 ± 10.8 (P= 0.087). Mean microvessel counts did not vary significantly with the spray pattern (30.1 ± 8.7), pushing pattern (31.4 ± 12.9), or mixed pattern of invasion (31.4 ± 12.9) (P= 0.920).Conclusions.Tumor angiogenesis in vulvar squamous cell carcinoma does not correlate positively with stage, survival, or pattern of invasion and cannot be used as a prognostic indicator.

Tumor angiogenesis as an independent prognostic indicator in human papillary thyroid carcinoma.

Angiogenesis has been determined to play a very important role in either the growth of solid tumors or their recurrence in distant organs. Microvessels stained immunohistochemically for the factor VIII-related antigen were counted in one hundred patients with papillary thyroid carcinoma in order to clarify the association of tumor angiogenesis with the prognosis of the disease. The mean microvessel count (MVC) was significantly higher in tumors with distant recurrence than those without recurrence. Disease-free survival of patients with a high MVC (>/= 23) was significantly worse than that of patients with a low MVC (</= 22), as well as the overall survival. In multivariate analysis, the MVC was most strongly correlated with disease-free survival, and was independent of other prognostic factors. In conclusion, the MVC is a potent prognostic indicator in papillary thyroid carcinoma.

Microvessel density, p53 overexpression, and apoptosis in invasive breast carcinoma.

AIM: To investigate the possibility of a correlation among microvessel density, p53 overexpression, and apoptosis in invasive breast carcinoma. METHODS: Microvessel density was analysed in 105 cases of invasive breast...

Neoangiogenesis: a putative marker of malignancy in non-small-cell lung cancer (NSCLC) development.

Several studies have documented a relevant prognostic role of microvessel count (MC) in non-small-cell lung carcinomas (NSCLC). However, no evidence has been reported about the involvement of neo-angiogenesis in the development of bronchial cancers. The aim of this study was to analyze microvessel density both in normal and in pathological features of the bronchial tree detected concomitantly with carcinomas. In a group of 34 patients resected for NSCLC, 48 bronchial lesions (hyperplasia, squamous metaplasia, moderate dysplasia and in situ carcinoma) were identified. In addition, 20 samples of normal bronchial epithelium from the same patients were analyzed. A monoclonal antibody was used in order to identify microvessels in the most intense areas of neovascularization from the bronchial specimens. MC was also analyzed in invasive components. An increased number of microvessels was observed from normal to dysplastic epithelium, including in situ carcinoma. Mean MC was significantly lower in normal, hyperplastic and squamous metaplastic epithelium than in dysplastic epithelium and in situ carcinoma. In particular, no differences were observed between normal and hyperplastic/metaplastic components, whereas a statistically significant difference appeared between the latter and dysplastic lesions. Moderate dysplasia and in situ carcinoma showed a number of microvessels in the lamina propria of their mucosa which were not significantly different from the invasive component, whereas hyperplastic/metaplastic lesions presented a much lower number of microvessels than invasive cancer. From these data it appears that normal bronchial epithelium and lesions associated with cancers of the bronchial tree show neovascularization in their stromal component. Hyperplasia and squamous metaplasia, unlike dysplasia and in situ carcinoma, show a low microvessel count, and they cannot represent precursor or incipient changes in the bronchial epithelium before the fully developed in situ stage has also been reached.

Clinicopathologic and prognostic significance of an angiogenic factor, thymidine phosphorylase, in human colorectal carcinoma.

Platelet-derived endothelial cell growth factor (PD-ECGF) is known to promote the development of new blood vessels, which are fundamental to tumor growth and metastasis. We previously found that thymidine phosphorylase (dThdPase) and PD-ECGF are the same protein. We retrospectively examined the expression of dThdPase in primary colorectal carcinomas, its association with angiogenesis and clinicopathologic findings, and its prognostic value. Tissues were obtained from the tumors of 163 patients whose colorectal carcinomas were completely removed by surgery. Microvessels assessed by immunostaining endothelial cells for factor VIII were counted on a 400x field in the most active areas of neovascularization within the tumor. We purified the monoclonal antibody against dThdPase and studied the expression of dThdPase in the same serial sections used for the detection of factor VIII. Those who carried out microvessel counting and dThdPase expression assessment had no knowledge of clinicopathologic findings. The significance of dThdPase in the prognosis of patients with colorectal carcinomas was also examined in the survival analysis of mortality follow-up data covering the period between 1984 through 1991. Reported P values are from two-sided tests of statistical significance. The mean microvessel count (+/- standard deviation) in dThdPase-positive colorectal carcinoma specimens (17.5 +/- 7.2) was higher (P < .001) than that in dThdPase-negative carcinoma specimens (9.3 +/- 5.5). The dThdPase positivity was in accordance with the microvessel count. dThdPase positivity showed highly significant statistical associations with tumor size, extent of invasion, lymph node metastasis, lymphatic invasion, and venous invasion. Cox regression analysis revealed that dThdPase expression was prognostic for poor disease outcome after adjustment for Dukes' stage and microvessel count. These findings suggest that higher levels of dThdPase expression in colorectal carcinomas are associated with more extensive angiogenesis, poor clinical and laboratory findings, and unfavorable clinical outcome. Inhibition of dThdPase in human colorectal carcinomas might improve prognosis for some patients.

Reconstruction of large mandibular defects and total avulsion of the scalp with microsurgical technique

Neovascularization of tumor tissue (tumor angiogenesis) is considered essential for tumor growth, proliferation and eventually metastasis. Microvessel density or count, a measure of tumor angiogenesis, correlates with clinical outcome in skin, breast, lung and prostate carcinomas. To determine whether an association of tumor angiogenesis and nodal metastasis exists in invasive bladder cancer, microvessel counts in 41 primary invasive stages (T2 to 4,NX,M0) bladder cancers were assessed. Microvessels were identified by immunostaining of endothelial cells for factor VIII-related antigen. Microvessels were scored in selected areas showing active neovascularization, either counting a 200X field (0.74 mm.2) or by using a 10 X 10 square ocular grid (0.16 mm.2). The microvessel count correlated with the presence of occult lymph node metastases (p less than 0.0001) by both techniques. The mean microvessel count in 27 patients without lymph node metastases was 56.2 microvessels per 200X field (standard deviation [SD] 29.5, range 7 to 130) or 28.6 microvessels per grid (SD 14.4, range 4 to 65). The 14 patients with histologically proved lymph node metastases showed mean 138.1 microvessels per 200X field (SD 37.9, range 82 to 202) or 74.7 microvessels per grid (SD 14.4, range 43 to 115). Good correlation was noted between area and grid counting (r = 0.97). Tumor T stage, grade and the presence of vascular or lymphatic invasion did not correlate with the presence of lymph node metastases (p = 0.41, 0.59 and 0.26, respectively). Microvessel count may provide important information regarding the risk of occult metastasis in patients with invasive bladder carcinomas.

Association of vascular endothelial growth factor expression with intratumoral microvessel density and tumour cell proliferation in human epidermoid lung carcinoma

Vascular endothelial growth factor (VEGF) expression, vascularisation and tumour cell proliferation were analysed in 91 human epidermoid lung carcinomas using immunohistochemistry. A polyclonal anti-VEGF antibody was used for VEGF expression, a polyclonal antibody directed against human von Willebrand factor (factor VIII) to identify blood vessels and the proliferating cell nuclear antigen (PCNA) as a marker for proliferating cells. Positive staining for VEGF was obtained in 54 out of 91 cases (59%), the number of blood vessels varied from zero to 64 counts (mean 9.4) and the proportion of PCNA-positive cells varied from 1.3% to 72.1% (mean 25.2%). The mean PCNA labelling index and mean microvessel count in VEGF-positive tumours were significantly higher than those in VEGF-negative tumours (Wilcoxon rank sum test, P<0.0001; p<0.05). In addition, PCNA labelling index significantly increased with increasing VEGF expression (Jonckheere test, P<0.0001). In contrast, no association was found between PCNA labelling index and tumour vascularity (r=0.07, P=0.48). The close correlation of VEGF expression with tumour cell proliferation and microvessel density suggests that VEGF acts both as an autocrine growth factor and as stimulator for angiogenesis. However, tumour cell proliferation and microvessel growth and/or density may be regulated by separate mechanisms.

Expression of Thymidine Phosphorylase in Human Gastric Carcinoma

The activity of thymidine phosphorylase (dThdPase) has heen reported to increase in several types of malignant tumors. Experimental evidence has shown that dThdPase is identical to platelet‐derived endothelial cell growth factor, and that dThdPase has angiogenic activity. We examined the expression of dThdPase to investigate whether the expression of dThdPase correlates with angiogenesis, clinicopathologic features and the prognosis of patients with human gastric carcinomas. Microvessels were assessed by immnnostaining endothelial cells for factor VIII. We counted microvessels in the tumors of 158 patients whose tumors were completely removed surgically. Microvessels were counted in a × 400 field in the most active areas of neovascularization. We purified a monoclonal antibody (TMA‐1) against dThdPase and studied the expression of dThdPase using TMA‐1 in the same serial sections as those used for the detection of factor VIII. The correlation between angiogenesis and dThdPase, and the clinicopathological significance of dThdPase, in patients with gastric carcinoma were examined. The positive expression of dThdPase was more frequent (P<0.001) in gastric carcinomas (67/158, 43.4%) than that in normal tissues (12/158, 7.6%). The average microvessel count in dThdPase‐positive gastric carcinomas was higher (P<0.001) than that in dThdPase‐negative carcinomas. The percentage of gastric carcinoma cells expressing dThdPase was significantly correlated with the microvessel count (P<0.001). Further, the average size of dThdPase‐positive carcinomas was significantly larger (P<0.001) than that of negative carcinomas and the mean microvessel count in dThdPase‐positive gastric carcinomas was also significantly higher (P<0.001) than that in dThdPase‐negative carcinomas. There was a significant correlation between the positive expression of dThdPase and microvessel count (P<0.001) or lymph node metastasis (P=0.013) by multivariate logistic analysis. Further, patients with dThdPase‐positive carcinoma showed a significantly worse prognosis than those with dThdPase‐negative carcinoma overall and in stage III. These findings indicate that the expression of dThdPase in gastric carcinomas is related to progression and metastasis, and this enzyme affects the prognosis of some patients with the disease.

MICROVESSEL QUANTIFICATION AS A MEASURE OF ANGIOGENIC ACTIVITY IN BENIGN BREAST-TISSUE LESIONS - A MARKER FOR PRECANCEROUS DISEASE

Neovascularization is a key step in the transformation of normal breast tissue into a cancerous phenotype. We investigated the angiogenic activity of 58 cases of histologically confirmed benign breast lesions quantitating angiogenic activity by factor VIII highlighting of endothelial cells. The mean microvessel count (MVC) for all patients was 51 per 0.19 mm(2) in the area of highest angiogenic activity at x400 magnification (range 21-113 per mm(2)). MVC in benign tissues were similar to those found previously in cancer tissues. These data suggest that the 'angiogenic switch' occurs early in breast transformation and that a role may exist for the use of MVC in the identification of persons at heightened risk for subsequent development of breast cancer.

Angiogenesis in endometrial hyperplasia and stage I endometrial carcinoma.

To evaluate angiogenesis in endometrial hyperplasia and stage I endometrial carcinoma, and to investigate the relationship between angiogenesis and tumor grade and depth of invasion. Three groups of patients were analyzed: control patients who underwent hysterectomy for benign conditions (n = 19), patients with endometrial hyperplasia (n = 24), and patients with stage I endometrial carcinoma (n = 34). All hysterectomy specimens were stained immunohistochemically for factor VIII-related antigen as a sensitive and specific marker for vascular endothelium. Areas close to the deepest myometrial invasion or those with the highest grade of endometrial hyperplasia and the highest angiogenic intensity were selected. Three fields (x 400) were selected for each slide, and the mean microvessel count was calculated. Statistical analysis included Mann-Whitney U test or Kruskal-Wallis analysis of variance and Dunn post hoc procedure. P < .05 was considered significant. A significant difference was found between the microvessel count of controls versus the group with complex endometrial hyperplasia (median 21, range 16-80, versus median 38, range 20-130; P < .05). Microvessel counts of complex endometrial hyperplasia were significantly higher than those of simple hyperplasia (median 25, range 16-42; P < .05) and significantly lower than counts of endometrial carcinoma (median 77.5, range 19-189; P < .05). Microvessel counts in complex hyperplasia were not significantly different than those of noninvasive stage I endometrial carcinoma (median 38, range 20-130, versus median 44, range 19-119; P = .5). In cases of stage I endometrial carcinoma, a higher number of microvessels was noted in specimens with myometrial invasion than in those without myometrial invasion (median 44, range 19-119, versus median 83, range 19-189; P < .01). A higher number of microvessels was noted in cases with grade 2 than in those with grade 1, stage I endometrial carcinoma (median 44, range 19-98, versus median 96, range 63-189; P < .001). Complex endometrial hyperplasia and endometrial carcinoma are angiogenic. Furthermore, in stage I endometrial carcinoma, greater depth of invasion and higher tumor grade are directly correlated with angiogenic intensity.

Angiogenesis in endometrial hyperplasia and stage I endometrial carcinoma

To evaluate angiogenesis in endometrial hyperplasia and stage I endometrial carcinoma, and to investigate the relationship between angiogenesis and tumor grade and depth of invasion.Three groups of patients were analyzed: control patients who underwent hysterectomy for benign conditions (n = 19), patients with endometrial hyperplasia (n = 24), and patients with stage I endometrial carcinoma (n = 34). All hysterectomy specimens were stained immunohistochemically for factor VIII-related antigen as a sensitive and specific marker for vascular endothelium. Areas close to the deepest myometrial invasion or those with the highest grade of endometrial hyperplasia and the highest angiogenic intensity were selected. Three fields (x 400) were selected for each slide, and the mean microvessel count was calculated. Statistical analysis included Mann-Whitney U test or Kruskal-Wallis analysis of variance and Dunn post hoc procedure. P < .05 was considered significant.A significant difference was found between the microvessel count of controls versus the group with complex endometrial hyperplasia (median 21, range 16-80, versus median 38, range 20-130; P < .05). Microvessel counts of complex endometrial hyperplasia were significantly higher than those of simple hyperplasia (median 25, range 16-42; P < .05) and significantly lower than counts of endometrial carcinoma (median 77.5, range 19-189; P < .05). Microvessel counts in complex hyperplasia were not significantly different than those of noninvasive stage I endometrial carcinoma (median 38, range 20-130, versus median 44, range 19-119; P = .5). In cases of stage I endometrial carcinoma, a higher number of microvessels was noted in specimens with myometrial invasion than in those without myometrial invasion (median 44, range 19-119, versus median 83, range 19-189; P < .01). A higher number of microvessels was noted in cases with grade 2 than in those with grade 1, stage I endometrial carcinoma (median 44, range 19-98, versus median 96, range 63-189; P < .001).Complex endometrial hyperplasia and endometrial carcinoma are angiogenic. Furthermore, in stage I endometrial carcinoma, greater depth of invasion and higher tumor grade are directly correlated with angiogenic intensity.

Tumor Angiogenesis Correlates with Lymph Node Metastases in Invasive Bladder Cancer

Neovascularization of tumor tissue (tumor angiogenesis) is considered essential for tumor growth, proliferation and eventually metastasis. Microvessel density or count, a measure of tumor angiogenesis, correlates with clinical outcome in skin, breast, lung and prostate carcinomas. To determine whether an association of tumor angiogenesis and nodal metastasis exists in invasive bladder cancer, microvessel counts in 41 primary invasive stages (T2 to 4,NX,M0) bladder cancers were assessed. Microvessels were identified by immunostaining of endothelial cells for factor VIII-related antigen. Microvessels were scored in selected areas showing active neovascularization, either counting a 200X field (0.74 mm. 2) or by using a 10 X 10 square ocular grid (0.16 mm. 2). The microvessel count correlated with the presence of occult lymph node metastases (p less than 0.0001) by both techniques. The mean microvessel count in 27 patients without lymph node metastases was 56.2 microvessels per 200X field (standard deviation [SD] 29.5, range 7 to 130) or 28.6 microvessels per grid (SD 14.4, range 4 to 65). The 14 patients with histologically proved lymph node metastases showed mean 138.1 microvessels per 200X field (SD 37.9, range 82 to 202) or 74.7 microvessels per grid (SD 14.4, range 43 to 115). Good correlation was noted between area and grid counting (r = 0.97). Tumor T stage, grade and the presence of vascular or lymphatic invasion did not correlate with the presence of lymph node metastases (p = 0.41, 0.59 and 0.26, respectively). Microvessel count may provide important information regarding the risk of occult metastasis in patients with invasive bladder carcinomas.

VASCULAR ENDOTHELIAL GROWTH-FACTOR EXPRESSION AND ANGIOGENESIS IN NONSMALL CELL LUNG CARCINOMAS

Vascular endothelial growth factor (VEGF), a secreted endothelial-specific growth factor, and microvessel density was examined in 204 primary non-small cell lung carcinomas. The expression of VEGF was evaluated by immunohistochemical staining using an anti-VEGF antibody. Positive staining was obtained in 125 out of 204 cases (61%). Tumor vascularity was quantitatively assessed by microvessel counting after staining with the endothelial-specific marker factor VIII. The mean microvessel count for all patients was 9.6+/-10.4. Expression of VEGF was closely associated with increment of microvessel density. Postoperative follow-up of patients demonstrated a trend that survival time of patients with VEGF-positive tumors was worse than that of patients with VEGF-negative tumors. In contrast, microvessel density was not a prognostic factor.