Multivariate analysis of flow data in breast lesions and validation in a normal clinical setting

PURPOSE

To improve differentiation between benign and malignant breast lesions by Doppler measurements and to validate results in a normal clinical setting in comparison to study conditions.

MATERIALS AND METHODS

Doppler measurements of 458 patients were compared in benign and malignant tumors in a prospective study. In a multivariate analysis a diagnostic score was developed using a logistic regression model and stepwise selection. These results were compared with 272 patients who were examined under routine clinical conditions.

RESULTS

Most measurements showed highly significant (p < 0.001) differences between benign and malignant tumors. For each measurement we considered two cut-points to define a diagnostic rule. Despite significant differences, none of the corresponding classification rules exceeded 90 % sensitivity and specificity. Multivariate analysis selected a model including age and the number of arteries and contralateral arteries. Although significant, the last factor barely improved diagnostic accuracy. Therefore, we deleted it from the multivariate model. Based on a simple model including age and the number of tumor arteries, we defined classification rules with high sensitivity and specificity. The RI measurement did not improve the discriminatory power of our score. In the validation study the sensitivity decreased from 89 - 98 % to 58 - 78 % with a specificity of 82 - 92 % vs. 83 - 86 %.

CONCLUSION

Color Doppler can be used for breast cancer differentiation. However, in the clinical routine the sensitivity decreases considerably compared with optimized study conditions.

Lymphatic microvessel density, VEGF-C, and VEGFR-3 expression in different molecular types of breast cancer

BACKGROUND

Breast cancer is a heterogeneous disease and five major distinct molecular types have been characterized by gene analysis and immunohistochemistry. The molecular types of breast cancer have different behavior, a particular profile of response to therapy, reflected in the differential survival of patients. Previous findings showed a particular preference for lymph node and distant metastases of different molecular types, but the specific lymphangiogenic profile of these types is lacking.

PATIENTS AND METHODS

We investigated the differential expression vascular endothelial growth factor-C (VEGF-C), vascular endothelial growth factor receptor-3 (VEGFR-3) and D2-40 by immunohistochemistry, to evaluate lymphangiogenesis and the lymphatic microvessel density (LMVD), in patients with breast cancer, stratified according to the molecular classification.

RESULTS

There was a differential expression of VEGF-C/VEGFR-3 and D2-40 in different molecular types of breast cancer, with highest level of expression for these markers being found in HER2 and luminal B types and the lowest in basal-like type. The lowest value of both intratumoral and peritumoral LMVD were found in normal-like type breast cancer. VEGF-C expression did not correlate with the grade of the tumor, but a significant correlation was found with lymph node metastasis. VEGFR-3 expression was found in 66.66% of the cases and correlated with the expression of VEGF-C in tumor cells. There was a positive correlation between VEGF-C, VEGFR-3 and LMVD only in the HER2 type, and a positive correlation in HER2 and normal-like types with VEGFR-3 expression in tumor cells. In addition, there was a correlation between HER2 type, VEGF-C and VEGFR-3 expression in tumor cells and lymphatic endothelium, respectively, and LMVD.

CONCLUSION

Our results support a differential signature of lymphangiogenesis in different molecular types of breast cancer and these findings may have a direct impact on prognosis and therapeutic strategy of this disease.

D2-40: an additional marker for myoepithelial cells of breast and the precaution in interpreting tumor lymphovascular invasion

D2-40 is a recently available mouse monoclonal antibody specific for human podoplanin and has been used in identifying lymphovascular invasion (LVI) of tumors. Although its expression has been evaluated in other tissues, its use as a marker for myoepithelial cells (MEC) of breast has not been studied. To explore its expression in the MEC of breast, paraffin-embedded tissue blocks from 48 patients with breast diseases were selected to include usual ductal hyperplasia (UDH, 41 cases), atypical ductal hyperplasia (ADH, 4 cases) and ductal carcinoma in situ (DCIS, 17 cases). Normal breast parenchyma and invasive carcinoma coexisting in the tissue sections were also included in the study. Immunohistochemistry for D2-40, calponin and p63 was performed and the staining patterns were reviewed and compared. D2-40 immunohistochemical staining is positive in the cytoplasm of MEC in UDH, ADH, and the majority of DCIS. The staining pattern of D2-40 is comparable with that of calponin, however D2-40 staining of MEC is weaker than that of calponin and with less background. In addition, myoepithelial cells and myofibroblasts at the edge of retraction spaces of DCIS are also stained by D2-40 that could be misinterpreted as tumor LVI. In conclusion, D2-40 immunohistochemistry reliably identifies the MEC of breast in a variety of lesions in a pattern similar to that of calponin and p63, and can be used as an additional MEC marker. Caution should be exercised when interpreting the staining of cells surrounding DCIS and carcinoma with retraction artifact.

Columnar cell lesions and pseudoangiomatous hyperplasia like stroma: is there an epithelial-stromal interaction?

The significance of association between cancer and its microenvironment has been increasingly recognized. It has been shown in animal models that interaction between neoplastic epithelial cells and adjacent stroma can modulate tumor behavior. Carcinoma associated stromal cells can transform normal epithelial cells into neoplastic cells. In breast, columnar cell lesions are non-obligate precursors of low grade ductal carcinoma in situ. Columnar cell lesions can be seen intimately associated with PASH-like-stroma, a lesion we termed as CCPLS. Our aim is to investigate epithelial-stromal interactions in CCPLS and compare them to PASH without columnar cell lesions in breast core needle biopsies. Normal terminal duct lobular unit (TDLU) epithelium was seen in association with columnar cell lesions as well as PASH. Eight (8) cases of each category were examined by a panel of immunostains: CD117 (C-kit), CD34, CD105, bFGF, AR, ER-beta, MIB-1. We observed a markedly decreased expression of c-kit in columnar cell lesions compared to TDLU-epithelium. CD105 showed a quantitative increase in activated vessels in CCPLS compared to PASH. A subset of CCPLS and PASH were androgen receptor positive. A strong nuclear positivity for ER-beta is observed in the epithelium and stroma of all CCPLS cases. We conclude that (1) activated blood vessels predominate in CCPLS; (2) A molecular alteration is signified by c-kit loss in columnar cell lesions; (3) ER-beta and androgen receptor positivity indicate CCPLS are hormonally responsive lesions. Our study suggests an intimate vascular and hormone dependent epithelial-stromal interaction exists in CCPLS lesions.

An expression signature of syndecan-1 (CD138), E-cadherin and c-met is associated with factors of angiogenesis and lymphangiogenesis in ductal breast carcinoma in situ

INTRODUCTION

Heparan sulphate proteoglycan syndecan-1 modulates cell proliferation, adhesion, migration and angiogenesis. It is a coreceptor for the hepatocyte growth factor receptor c-met, and its coexpression with E-cadherin is synchronously regulated during epithelial-mesenchymal transition. In breast cancer, changes in the expression of syndecan-1, E-cadherin and c-met correlate with poor prognosis. In this study we evaluated whether coexpression of these functionally linked prognostic markers constitutes an expression signature in ductal carcinoma in situ (DCIS) of the breast that may promote cell proliferation and (lymph)angiogenesis.

METHODS

Expression of syndecan-1, E-cadherin and c-met was detected immunohistochemically using a tissue microarray in tumour specimens from 200 DCIS patients. Results were correlated with the expression patterns of angiogenic and lymphangiogenic markers. Coexpression of the three prognostic markers was evaluated in human breast cancer cells by confocal immunofluorescence microscopy and RT-PCR.

RESULTS

Coexpression and membrane colocalization of the three markers was confirmed in MCF-7 cells. E-cadherin expression decreased, and c-met expression increased progressively in more aggressive cell lines. Tissue microarray analysis revealed strong positive staining of tumour cells for syndecan-1 in 72%, E-cadherin in 67.8% and c-met in 48.6% of DCIS. E-cadherin expression was significantly associated with c-met and syndecan-1. Expression of c-met and syndecan-1 was significantly more frequent in the subgroup of patients with pure DCIS than in those with DCIS and a coexisting invasive carcinoma. Levels of c-met and syndecan-1 expression were associated with HER2 expression. Expression of c-met significantly correlated with expression of endothelin A and B receptors, vascular endothelial growth factor (VEGF)-A and fibroblast growth factor receptor-1, whereas E-cadherin expression correlated significantly with endothelin A receptor, VEGF-A and VEGF-C staining.

CONCLUSION

Syndecan-1, E-cadherin and c-met constitute a marker signature associated with angiogenic and lymphangiogenic factors in DCIS. This coexpression may reflect a state of parallel activation of different signal transduction pathways, promoting tumour cell proliferation and angiogenesis. Our findings have implications for future therapeutic approaches in terms of a multiple target approach, which may be useful early in breast cancer progression.

Optical mammography: a new technique for visualizing breast lesions in women presenting non palpable BIRADS 4-5 imaging findings: preliminary results with radiologic-pathologic correlation

The purpose of this prospective study is to determine the diagnostic accuracy of near-infrared breast optical absorption imaging in patients with Breast Imaging Reporting and Data System (BIRADS) 4–5 non-palpable lesions scheduled for biopsy, using pathology after core or excisional biopsy as a reference. The patient's breast was positioned onto a panel of red light-emitting diodes (640 nm). A soft membrane was inflated to exert a uniform pressure on the breast. Transmitted light was detected using a CCD camera. The entire acquisition sequence took 1 minute. Image processing generated dynamic images displayed in colour scale, to reveal time-dependent changes in the transmitted light intensity caused by the pressure change. Dynamic curves were classified in two categories: consistently decreasing intensity suspicious for malignancy, and sinusoidal increasing intensity considered as benign. Seventy-eight women consulting for non-palpable breast lesions were initially included in the study. An imaging–histology correlation was obtained for seventy-two patients, the remaining six patients were excluded for technical optical scan reasons. We experienced an overall sensitivity of 73% and specificity of 38%, the false negative results being mainly small size (<10 mm) infiltrating malignant lesions and ductal carcinoma in situ (DCIS). False positive results were seen in benign proliferative lesions. Dynamic optical breast imaging is a novel, low-cost, non-invasive technique yielding a new type of information about the physiology of breast lesions. Absorption is due to haemoglobin and its products, therefore reflecting the angiogenic status of breast tumours.

Does thymidine phosphorylase correlate with angiogenesis in intraductal carcinoma of the breast?

OBJECTIVE

To determine the association between thymidine phosphorylase (TP) and angiogenesis, and other conventional prognostic markers. We also evaluated interobserver and intraobserver reliability for TP expression in ductal carcinoma, to achieve a more consistent results.

METHODS

Our study included all cases diagnosed in Adnan Menderes University Medical Faculty Hospital, Aydin, Turkey as invasive ductal carcinoma or ductal carcinoma in situ (DCIS) with proven component of (>30%), between January 2003 and February 2005. The total number of the cases was 27 and their median age was 50 years. All sections were stained using monoclonal antibody-TP and examined at x40 magnification. Either nuclear or cytoplasmic staining was accepted as positive. The histoscore (H-score) was calculated for each specimen. The tumor stromal vascularity was assessed by monoclonal anti-CD34; and areas of intense vascularization were determined. Conventional immunohistochemical markers such as c-erb B2, Ki-67, estrogen and progesterone receptors and p53 were also applied to all slides. Three pathologists blindly examined each slide under 10 high-power fields (10 HPF) for 2 times in a 2 months period.

RESULTS

There was no significant association between stromal vascularity and TP staining of cancer cells (p=0.1) and no correlation was determined between H-scores for TP staining in ductal carcinoma and DCIS components (p=0.5).

CONCLUSION

There was no significant correlation noted between stromal and periductal vascularity with the anti-CD34 antibody was used. No significant correlation was identified between the TP H-score and stromal or periductal vascularity.

[Values of color Doppler flow imaging and imaging changes of breast fascia and ligament in differential diagnosis of small breast neoplasms]

BACKGROUND & OBJECTIVE

Color Doppler flow imaging (CDFI) has been widely applied to the diagnosis of breast neoplasms. But combined use of CDFI and imaging changes of breast fascia and ligament (superficial and deep fascia, and Cooper's ligament) on the differential diagnosis of small breast neoplasms (< or =2 cm) has rarely been reported. This study was to explore the value of combined use of CDFI and imaging changes of breast fascia and ligament in differential diagnosis of small breast neoplasms.

METHODS

CDFI was performed on 110 patients with small breast neoplasms. Among them, 52 cases were diagnosed to be benign by pathologic examination after surgery, while the rest 58 were malignant. The blood flow and Doppler image inside and around the breast lesions were analyzed. Four grades were classified according to blood flow imaging. The infiltration of breast fascia and ligament was also considered. The CDFI result was compared with that of pathologic examination.

RESULTS

The correct diagnosis rates of CDFI in diagnosing benign and malignant small breast neoplasms were 90.4% and 84.5%, respectively. The false-positive and false-negative rates of CDFI were 9.6% and 15.5%, respectively. There were obvious differences in blood flow grading, systolic maximum velocity (V(max)), resistance index (RI), and imaging changes of superficial, deep fascia and Cooper's ligament between benign and malignant small breast neoplasms.

CONCLUSION

Combination of CDFI with imaging changes of breast fascia and ligament is valuable in clinical diagnosis and differential diagnosis of small breast neoplasms.

A putative role for psoriasin in breast tumor progression

Psoriasin (S100A7) was identifi;ed as a gene highly expressed in psoriatic keratinocytes and highly and more frequently expressed in ductal carcinoma in situ (DCIS) than in invasive breast carcinomas (IBC), suggesting a potential role in tumor progression. Psoriasin expression is associated with poor prognostic factors in both DCIS and IBC. Several putative functions have been proposed for psoriasin in various disease types, but none of these can fully explain its involvement in breast tumor progression. Here, we show that down-regulation of endogenous psoriasin expression via stable short hairpin RNAs in a human IBC cell line (MDA-MB-468) increases cell migration and invasion without influencing cell proliferation and survival in vitro but inhibits tumor growth in vivo. These seemingly paradoxical results are potentially explained by the dramatic up-regulation and down-regulation of matrix metalloproteinase-13 and vascular endothelial growth factor (VEGF), respectively, observed in cells with decreased psoriasin levels compared with controls. Correlating with this, high psoriasin expression in human IBC is associated with increased angiogenesis and worse clinical outcome, and psoriasin mRNA levels are coordinately regulated with VEGF and other genes related to hypoxia and mitochondrial reactive oxygen species (ROS). Based on these results, we propose that psoriasin may play a role in breast tumor progression by promoting angiogenesis and enhancing the selection for cells that overcome its anti-invasive function. This hypothesis may explain why psoriasin expression is highest in high-grade and/or estrogen receptor-negative tumors, as these are associated with increased hypoxia and ROS, a setting in which the angiogenic effects of psoriasin are most important.

Skin-sparing mastectomy

Background

Skin-sparing mastectomy (SSM) is a new technique being used in a variety of clinical settings. This article reviews the published data on SSM to establish its current role in clinical practice.

Methods

A Medline search was carried out using the key words ‘skin-sparing mastectomy’ to identify English-language articles published between 1990 and 2004 and further material referenced in these publications.

Results

SSM is most commonly used for surgical prophylaxis and to treat in situ and early invasive disease in patients who request immediate breast reconstruction. SSM and non-SSM result in similar surgical and oncological outcomes, but skin flap ischaemia is more common after SSM and is associated with a range of risk factors, including smoking.

Conclusion

SSM has become an established procedure in breast surgery, but there is a lack of prospective data on which to make evidence-based decisions about its use in individual patients.

Angiogenic potential of ductal carcinoma in situ (DCIS) of human breast

AIMS

Comedo carcinoma is generally regarded as the subtype of ductal carcinoma in situ (DCIS) most likely to progress to invasive carcinoma. Increased angiogenesis could be associated with an enhanced risk of progression and might therefore be a marker of poor prognosis, as can be demonstrated for invasive breast tumours. Therefore, the present study investigates the correlations between the expression of oncoproteins (HER2, HER1/EGFR), angiogenic growth factors (VEGF and PD-ECGF/TP) and microvessel density (MVD) in DCIS.

METHODS AND RESULTS

Forty-six breast cancer specimens of DCIS were tested immunohistochemically for the expression of angiogenic factors and oncoproteins. Different vascular distribution patterns of DCIS were examined semiquantitatively. Our results showed a significantly inverse correlation between HER1/EGFR and comedo-type DCIS (P = 0.048), but HER1/EGFR expression seemed to be independent of HER2 overexpression. VEGF expression was significantly associated with endoglin expression (P = 0.031) and the cuffing phenomenon (P = 0.017).

CONCLUSIONS

The significantly inverse correlation between HER1/EGFR and comedo-type DCIS and the observation that VEGF and the other angiogenic factors tested are independent of HER2 overexpression, suggest that progression of comedo-type DCIS and angiogenesis in breast carcinoma are not regulated via the HER1/EGFR or HER2 pathway.

Increased ipsilateral whole breast vascularity as measured by contrast-enhanced magnetic resonance imaging in patients with breast cancer

BACKGROUND

Tumor-induced neovessel formation identified by gadolinium-enhanced magnetic resonance imaging (MRI) is a commonly used marker for breast malignancy. The purpose of this study was to assess possible differences in whole-breast vascularity as measured by contrast-enhanced MRI in the ipsilateral and contralateral breasts of patients with unilateral breast malignancies.

METHODS

Gadolinium-enhanced MRI of the breast using a Siemens 1.0-T scanner with dedicated breast coil was performed on 22 consecutive patients with histologically confirmed unilateral breast carcinoma. Whole-breast vascularity of the breast containing the carcinoma was estimated as increased, decreased, or similar compared with the contralateral unaffected breast. Breast vascularity was then correlated to clinical factors including tumor size, histology, multifocality, nodal involvement, and patient age and menopausal status.

RESULTS

Twenty patients had infiltrating carcinomas, and 2 patients had ductal carcinoma in situ. Four were multifocal. Fifteen of 22 patients demonstrated clear evidence of increased whole-breast vascularity in the ipsilateral breast containing the primary breast cancer compared with the contralateral breast. Although there was no clear correlation between the presence of increased whole-breast vascularity in the cancer-bearing breast with tumor size, histology, grade, mammographic appearance, or patient age and menopausal status, increased vascularity was present in 3 of 4 patients with multifocal disease and in 4 of 5 patients with metastatic disease in the axillary nodes.

CONCLUSIONS

Measurable increases in whole-breast vascularity can be identified by contrast-enhanced MRI and appear with increased frequency in the cancer-bearing breast. These findings suggest that factors other than tumor size and histology may influence development of macroscopic vessels during tumor progression and may be indicative of angiogenic tumor biology.

The phosphorylated form of connexin43 is up-regulated in breast hyperplasias and carcinomas and in their neoformed capillaries

We applied an antiserum (SA226P) specifically recognizing the phosphorylated form of connexin43 (P-Cx43) to human breast samples including normal breast samples, with fibrocystic disease (FCD), fibroadenomas (FA), in situ and infiltrating carcinomas of all major types, and miscellaneous extramammary tumors. The findings were compared with those obtained with commercial antisera recognizing all Cx43 forms (pan-Cx43). A subset of samples was stained for Her2-neu and p44/42 to mitogen-activated protein kinase. Paraffin step sections were used. Immunoblots were performed on frozen samples of a representative subset of cases. In the normal breast, FCD, and FA, SA226P stained strongly and extensively most myoepithelial cells (MECs); luminal cells remained unstained. In proliferative FCD and some cellular FA, SA226P stained MEC and the capillary endothelium (CE). In ductal and lobular in situ carcinomas, SA226P reacted strongly and diffusely with the remaining MEC, the CE, and the transformed luminal cells. SA226P stained all infiltrating carcinomas except the tubular variant. In all breast carcinomas, the CE within and adjacent to tumors and some myofibroblasts stained with SA226P. By contrast, pan-Cx43 stained weakly and sporadically the MEC and rare samples of invasive carcinomas. Notably, Mab p44/42 reacted in parallel with the samples stained with SA226P, whereas reactions with Her2 were negative. Immunoblot findings paralleled those obtained immunohistochemically. We conclude that P-Cx43, restricted to MEC in the normal breast, is up-regulated in the same cells in hyperplasias and dysplasias and FA and is strongly up-regulated in invasive carcinomas. Notably, in some proliferative FCD and in most in situ and infiltrating carcinomas, P-Cx43 is strongly expressed in CE within and adjacent to the lesions but not away from them. These findings were paralleled by the strong nuclear reactions noted with Mab p44/42. These phenomena, although not exclusive to malignancy, are particularly conspicuous in breast carcinomas and seemingly reflect active proliferation associated with abnormal gap junctional intercellular communication.

Angiogenin is up-regulated in the nucleus and cytoplasm in human primary breast carcinoma and is associated with markers of hypoxia but not survival

Angiogenin, a 14.2 kD polypeptide that was originally noted for its angiogenic activity, is now increasingly recognized to have a multiplicity of biological roles in both physiological and pathological conditions. In breast cancer, there are conflicting studies questioning the role of angiogenin. Here, the pattern of expression of angiogenin during the transition from normal breast tissue to ductal carcinoma in situ and invasive carcinoma is reported together with the correlates between the level of angiogenin in 239 invasive carcinomas and standard clinicopathological parameters, hypoxia-inducible factor (HIF)-1 alpha and the HIF-1 alpha target gene DEC-1. This study shows that angiogenin expression is up-regulated in the cytoplasmic and nuclear compartments in in situ carcinoma and invasive carcinoma compared with normal breast tissue and that angiogenin expression in invasive carcinomas is significantly positively associated with high tumour grade (p = 0.03), positive oestrogen receptor (ER) status (p = 0.01), HIF-1 alpha (p = 0.001) and DEC 1 (p = 0.001), but not with patient age (p = 0.8), tumour size (p = 0.25), lymph node status (p = 0.69), epidermal growth factor receptor (p = 0.56) or microvessel density (p = 0.32). No difference in relapse-free (p = 0.26) or overall (p = 0.63) survival was observed in patients stratified by angiogenin expression. This study suggests that angiogenin may be important in breast cancer progression and that, through its relationship with ER, it may be a target for tamoxifen.

Overexpression of beta1-chain-containing laminins in capillary basement membranes of human breast cancer and its metastases

INTRODUCTION

Laminins are the major components of vascular and parenchymal basement membranes. We previously documented a switch in the expression of vascular laminins containing the alpha4 chain from predominantly laminin-9 (alpha4beta2gamma1) to predominantly laminin-8 (alpha4beta1gamma1) during progression of human brain gliomas to high-grade glioblastoma multiforme. Here, differential expression of laminins was studied in blood vessels and ductal epithelium of the breast.

METHOD

In the present study the expressions of laminin isoforms alpha1-alpha5, beta1-beta3, gamma1, and gamma2 were examined during progression of breast cancer. Forty-five clinical samples of breast tissues including normal breast, ductal carcinomas in situ, invasive ductal carcinomas, and their metastases to the brain were compared using Western blot analysis and immunohistochemistry for various chains of laminin, in particular laminin-8 and laminin-9.

RESULTS

Laminin alpha4 chain was observed in vascular basement membranes of most studied tissues, with the highest expression in metastases. At the same time, the expression of laminin beta2 chain (a constituent of laminin-9) was mostly seen in normal breast and carcinomas in situ but not in invasive carcinomas or metastases. In contrast, laminin beta1 chain (a constituent of laminin-8) was typically found in vessel walls of carcinomas and their metastases but not in those of normal breast. The expression of laminin-8 increased in a progression-dependent manner. A similar change was observed from laminin-11 (alpha5beta2gamma1) to laminin-10 (alpha5beta1gamma1) during breast tumor progression. Additionally, laminin-2 (alpha2beta1gamma1) appeared in vascular basement membranes of invasive carcinomas and metastases. Chains of laminin-5 (alpha3beta3gamma2) were expressed in the ductal epithelium basement membranes of the breast and diminished with tumor progression.

CONCLUSION

These results suggest that laminin-2, laminin-8, and laminin-10 are important components of tumor microvessels and may associate with breast tumor progression. Angiogenic switch from laminin-9 and laminin-11 to laminin-8 and laminin-10 first occurs in carcinomas in situ and becomes more pronounced with progression of carcinomas to the invasive stage. Similar to high-grade brain gliomas, the expression of laminin-8 (and laminin-10) in breast cancer tissue may be a predictive factor for tumor neovascularization and invasion.

Mathematical modelling of comedo ductal carcinoma in situ of the breast

The growth of a tumour in a cylindrical duct with compliant walls is examined in order to model the early stages of ductal carcinoma in situ (DCIS) of the breast, the earliest known stage of breast cancer. A nutrient-limited growth model is formulated, in which cell movement is described by a Stokes flow constitutive relation. The interactions between the expansive forces created by tumour cell proliferation and the stresses that develop in the compliant basement membrane are studied using asymptotic and numerical methods. In this way we show how the duct wall deforms as the tumour grows and also how the progression of the tumour along the duct depends upon the stiffness of the wall. By varying key parameters we determine how treatment, protease production and the inclusion of the surrounding stroma affect the growth. Finally, we discuss the biological relevance of our results and suggest possible directions for future work.

Noninvasive Carcinoma of the Breast: Angiogenesis and Cell Proliferation

Context.—Angiogenesis and the cell proliferation index can predict the prognosis of invasive breast carcinoma; however, little is known of their roles in noninvasive tumor.

Objective.—To investigate the correlation of microvessel density and cell proliferation index with other histologic parameters (histologic type, nuclear grade, and mitotic count) in 65 cases of noninvasive carcinoma of the breast.

Design.—Formalin-fixed, paraffin-embedded tissues from 65 cases of carcinoma in situ of the breast were immunostained with antibody against factor VIII antigen and proliferation-associated nuclear antigen MIB-1. The microvessel density was measured by counting the total number of microvessels around the carcinoma in situ per 10 low-power microscopic fields. The cell proliferation index was calculated by counting MIB-1–positive nuclei in 100 tumor cells. A χ2 test and Spearman rank correlation test were used for statistical analysis.

Results.—The microvessel density and cell proliferation index of comedo-type, high-nuclear-grade ductal carcinomas in situ are significantly higher than those of either noncomedo type ductal carcinomas in situ or lobular carcinoma in situ (P &lt; .001).

Conclusions.—Angiogenesis and the cell proliferation index are active biological processes and may be considered as markers to separate low- and high-risk patients with noninvasive breast carcinomas.

Inactivation of the PTEN gene protein product is associated with the invasiveness and metastasis, but not angiogenesis, of breast cancer

PTEN is a novel tumor-suppressor gene located on chromosomal band 10q23. Loss of PTEN function has been implicated in the progression of several types of cancer, but the correlation between loss of PTEN expression and advanced carcinomas is not well established. The capacity for angiogenesis of a tumor is known to play a very important role in growth and metastasis, and there have been reports that PTEN relates to angiogenesis. In the present study, formalin-fixed and paraffin embedded tissues from 101 patients with breast carcinomas, including 88 cases of invasive ductal carcinomas and 13 cases of ductal carcinoma in situ (DCIS), were evaluated by immunohistochemical methods for the expression of PTEN and vascular endothelial growth factor (VEGF), as well as microvessel density (MVD). The results were compared with the clinicopathologic parameters. There was no loss of PTEN expression in any of the cases of DCIS, but 28 (32%) of the 88 invasive cases did not express PTEN. Loss of PTEN expression was associated with lymph node metastasis (P = 0.03), but did not correlate with tumor size, tumor grade, MVD or recurrence. VEGF expression significantly correlated with lymph node metastasis in invasive ductal carcinoma (P = 0.01). There was no correlation between the expression of PTEN and that of VEGF (P = 0.63). The present study suggests that loss of PTEN expression is common and correlates with tumor progression and lymph node metastasis in breast carcinoma. The relationship between loss of PTEN and progression of breast cancer may not be explained by modulation of angiogenesis.

Flt-4-positive vessel density correlates with vascular endothelial growth factor-d expression, nodal status, and prognosis in breast cancer

PURPOSE

Metastasis to the regional lymph nodes through the lymphatic vessels is a common step in the progression of cancer and an important prognostic factor in many types of cancer. Recent evidence suggests that tumor lymphangiogenesis promotes lymphatic metastasis, and that the presence of Flt-4 on tumor blood and lymphatic vessels may play a important role in mediating lymphangiogenic factor-induced neovascularization. We assessed flt-4-positive vessel density (FVD) in breast cancer, and examined whether FVD associates with lymph node metastasis, VEGF-D expression, or prognosis.

EXPERIMENTAL DESIGN

One hundred three invasive breast carcinomas with long-term follow-up were included in our study. Flt-4 was assessed using immunohistochemistry, then we analyzed the relationship between FVD and lymph node status, as well as VEGF-D expression and other established clinicopathological parameters. The relationship between FVD and prognosis was also investigated.

RESULTS

Mean FVD of "hot spot" was 29.3 +/- 22.5 for each case. FVD was correlated significantly with lymph node metastasis (P < 0.0001), VEGF-D expression (P = 0.0019), tumor size (P = 0.0015), estrogen receptor (P = 0.0211), progesterone receptor (P = 0.0462), and c-erbB-2 (P = 0.0326). Survival curves determined by the Kaplan-Meier method and univariate analysis demonstrated that high FVD was associated with both worse disease-free survival (P = 0.0035) and overall survival (P = 0.0336).

CONCLUSIONS

Increased FVD was correlated with lymph node metastasis and VEGF-D expression. High FVD may be a significant unfavorable prognostic factor for long-term survival in breast cancer. It is possible that Flt-4 becomes a target for antiangiogenic therapy to breast cancer.

Angiogenesis as determined by computerised image analysis and the risk of early relapse in women with invasive ductal breast carcinoma

The purpose of this study was to define the value of angiogenesis as a prognostic factor indicating early relapse. We assessed the relationship between parameters of angiogenesis (microvessel count--MVC, microvessel area--MVA and microvessel perimeter--MVP) and relapse-free survival at 50 months in 226 women with invasive ductal breast carcinoma. Anti CD31 antibody was used as a marker of endothelial cells. Microvessel density was measured according to Weidner et al. using a computerised image analysis. The mean parameters of angiogenesis were significantly higher in women with relapse than in those without recurrence within 50 months after surgery. In node negative patients relapse did not occur if MVC was below 38.7. In node-negative subgroup with grade II carcinomas parameters of angiogenesis in the primary tumour differed significantly depending on the presence or absence of relapse. Univariate and multivariate analysis showed the prognostic value of angiogenesis parameters in all study groups with respect to 50-month relapse-free survival. In node negative subgroup only 62.5% of women with tumors with high MVC and as much as 94.9% with low MVC survived 50 months without recurrence. In the Cox analysis of node-negative subgroup only MVC, MVP and MVA were the independent prognostic factors. In women with node-negative disease the evaluation of angiogenesis can identify a subgroup of patients with high risk of relapse, hence it may help in decisions concerning adjuvant therapy. Computerised image analysis is a good and objective technique for evaluating the intensity of angiogenesis in breast cancer.

TNP-470 inhibits 7,12-dimethylbenz[a]anthracene-induced mammary tumor formation when administered before the formation of carcinoma in situ but is not additive with tamoxifen

In many women pathologic lesions, such as hyperplasia and carcinoma in situ, precede invasive breast cancer. We have shown that tissue vascularity increases with histologic progression to invasive disease. Similarly, in the well-characterized 7,12-dimethylbenz[a]anthracene (DMBA) model of mammary tumorigenesis, preinvasive lesions exhibit increased vascularity with progression. Using this model we asked whether inhibition of angiogenesis would block progression and if so, at which stage. We treated rats with DMBA followed by the potent angiogenic inhibitor, TNP-470, and/or tamoxifen starting 1 day or 6 weeks later. Histopathology and in vitro angiogenic potential of mammary organoids were evaluated 3 months after DMBA. All statistical tests were two-sided. Early TNP-470 and tamoxifen treatment inhibited the formation of carcinoma in situ (p < 0.001) and invasive disease (p < 0.001). However, their effects were not additive, despite their unique mechanisms of action. TNP-470 administration begun at the time of microscopic carcinoma in situ formation was unable to prevent the further development of carcinoma in situ or invasive breast cancer, whereas tamoxifen was highly effective (p = 0.001). There was no added benefit of combining TNP-470 and tamoxifen. TNP-470 therapy, unlike tamoxifen, did not inhibit the angiogenic potential of DMBA-treated normal mammary organoids, supporting its lack of a direct effect on the epithelium. These data provide proof-in-principle that inhibition of angiogenesis early in mammary tumorigenesis prevents mammary tumor formation in a hormone-sensitive model, indicating that angiogenesis is a potential target for cancer chemoprevention. Interactions with other chemopreventive strategies and the timing of administration must be thoroughly examined in vivo.

Blood markers for vasculogenesis increase with tumor progression in patients with breast carcinoma

Recent studies show that AC133-a hematopoietic stem cell antigen, when coex-pressed with endothelial markers, identifies a population of endothelial precursor cells (EPCs) in peripheral blood that function in tumor vasculogenesis in animals. Little is known about whether EPCs contribute to human tumor vasculogenesis. We attempted to determine if, through increased peripheral expression of AC133 or endothelial markers previously associated with EPCs,VEGFR-2 and Tie-2, we could detect an EPC response in the blood of patients with breast carcinoma. Thirty patients were segregated based on their breast biopsy histology into infiltrating carcinoma, DCIS and control groups. Using Real Time PCR, we measured the expression of the aforementioned markers in reverse transcribed RNA extracts from preoperative peripheral blood specimens. The cancer patients had significantly elevated Tie-2 expression with the highest levels associated with infiltrating carcinoma. Our data suggest increased circulating EPC markers in tumor patients, but further study of this cell population is needed to better define its role in tumor vasculogenesis.

Angiogenesis and invasive recurrence in ductal carcinoma in situ of the breast

The development of an invasive recurrence following treatment for ductal carcinoma in situ (DCIS) converts a non-fatal disease to one associated with mortality. To date, no pathological or molecular features have been found to predict for the type of recurrence. Previous studies have suggested that in DCIS angiogenesis may be an important factor in determining the transformation from in situ to invasive carcinoma. We looked at 355 cases of DCIS and found that 32 had subsequently developed recurrent disease. In these 32 cases and in matched controls, periductal vascular density was determined using morphometry and anti-endothelial antibodies, von Willebrand factor (vWF) and CD34. Vascular density was related to the risk of both invasive and in situ recurrence. Normal lobules at least 2 mm away were used as controls. Differences in the phenotype of individual blood vessels was detected by performing dual staining immunofluorescence on selected cases. The microvessel density (MVD), as detected with the CD34 antibody, was higher around foci of DCIS than around normal breast lobules (P=0.001). Furthermore, it was significantly higher in cases of DCIS that recurred (P<0.0001). The findings with the vWF antibody were less clear cut and suggested a trend in decreasing MVD with increasingly aggressive disease. Dual immunofluorescence staining shows that the increase in MVD seen around DCIS is due to an increase in CD34+/vWF-blood vessels. An increase in CD34+/vWF-of blood vessels may be able to predict cases of DCIS that are at a high risk of developing a recurrence.

Thrombospondin 1 protein expression relates to good prognostic indices in ductal carcinoma in situ of the breast

AIM

Angiogenesis plays an important role in tumour growth and has been shown to occur around both in situ and invasive tumours. The degree of angiogenesis within tumours depends on the balance of pro-angiogenic and anti-angiogenic factors. One such anti-angiogenic factor is thrombospondin 1 (TSP-1). This study investigates the pattern of expression of TSP-1 in ductal carcinoma in situ (DCIS) of the breast and its relation to the surrounding microvessel pattern and density.

MATERIALS/METHODS

The expression of TSP-1 was studied in formalin fixed, paraffin wax embedded sections from 58 cases of pure DCIS, using a monoclonal antibody against TSP-1 and the avidin-biotin-diaminobenzidine immunoperoxidase detection system. Vessels were stained with a monoclonal antibody to the endothelial cell marker CD31. Stromal microvessel density was assessed by counting "hot spots" within 500 micro m of the basement membrane of involved ducts using a 25 point Chalkey graticule.

RESULTS

TSP-1 staining of the basement membrane around duct spaces with DCIS was seen in 69% of cases. In addition, staining of the stroma between involved duct spaces was seen in 31% of cases, with a fibrillary pattern identical to that seen in invasive breast carcinomas. In 12% of cases no staining for TSP-1 was seen. Two patterns of vascularity were identified. A cuff of vessels immediately adjacent to the basement membrane of ducts with DCIS was seen in 71% of cases. The presence of stromal TSP-1 was significantly associated with DCIS showing no/little necrosis (p = 0.01) and no/little periductal inflammation (p = 0.04). There was a trend between the presence of stromal TSP-1 and tumour cell negativity for p53 (p = 0.087). The stromal microvessel Chalkey point count ranged between 3.33 and 16. An increased stromal microvessel count was associated with high histological grade (p = 0.02), extensive necrosis (p = 0.047), and pronounced periductal inflammation (p = 0.049). There was no association between the presence of stromal TSP-1 and stromal microvessel density.

CONCLUSIONS

TSP-1 is expressed in the stroma around DCIS and in the immediately adjacent basement membrane. Expression of stromal TSP-1 is lost in DCIS with more aggressive histological features. The absence of a relation with microvessel density suggests that other angiogenic factors may play an important role in DCIS.

Angiogenesis, thrombospondin, and ductal carcinoma in situ of the breast

Angiogenesis, the growth of new vessels from existing vasculature, plays an essential role in tumour development. The process involves interaction between a variety of cells, growth factors, and components of the extracellular matrix, regulated by pro-angiogenic and anti-angiogenic factors. This review profiles these factors, outlines the available methods for measuring new vessel formation, and discusses the importance of angiogenesis in breast cancer, with emphasis on ductal carcinoma in situ.

Measuring microvascular density in tumors by digital dissection

OBJECTIVE

To develop and validate a digital dissection techniquefor measuring the cross-sectional area of blood vessels in histologic sections of tumors routinely stained with hematoxylin and eosin.

STUDY DESIGN

The procedure was first validated in four experimental tumors in rats by comparing the results of the digital dissection technique to functional estimates of the blood volume in the tumors as measured by dynamic, contrast-enhanced magnetic resonance imaging. The method was then tested on a variety of experimental and human tumors.

RESULTS

The digital dissection technique yielded results that exactly matched the functional measurements of blood volume infour experimental tumors. Digital dissection of 40 additional tumors in rats showed that 21 infiltrating ductal carcinomas had significantly greater microvascular density (MVD) than 19 benign fibroadenomas (12% vs. 7.9%, P=.028 by two-tailed t test). In 10 human breast carcinomas the MVD was consistently greater than the measurement of blood vessel density as identified by immunohistochemical staining for factor VIII. The between-run coefficients of variation for the MVD assay were 12% (n = 5) for a human breast cancer and 18% (n = 5)for an experimental rat tumor.

CONCLUSION

The digital dissection technique is a reproducible, objective and accurate method of measuring MVD in sections of tumors that are routinely stained with hematoxylin and eosin.

Contrast-enhanced color Doppler ultrasound characteristics in hypervascular breast tumors: comparison with MRI

The aim of this study was to evaluate the accuracy of contrast-enhanced color Doppler ultrasound (CE-US) in comparison with contrast-enhanced MR imaging (CE-MRI) in the discrimination of hypervascularized breast tumors. An additional CE-US of the breast was preoperatively performed in 40 patients with a hypervascular breast lesion detected on CE-MRI. The presence of blood flow signals and the morphological characteristics of the vessels in the breast lesions were evaluated pre- and post-contrast administration, as well as the dynamic aspects of the Doppler signal, including time interval to maximum signal enhancement and persistence of the signal enhancement. Twenty-three carcinomas and 17 fibroadenomas were explored. Considering initial signal enhancement > 100% after the administration of contrast material as a criterion suggesting malignancy, CE-MRI showed a sensitivity of 100% and a specificity of 76.5% in the detection of malignant breast tumors. Color Doppler signals were consistently demonstrated in all carcinomas and in 68.7% of fibroadenomas after the administration of Levovist, with CE-US showing a sensitivity of 95.6% and a specificity of 5.9%. Neither the mean number of vessels per tumor, nor the location of vessels, the time to maximum increase of the Doppler signal or the persistence of signal enhancement showed significant differences between benign and malignant lesions. Additional CE-US does not increase the low specificity of MRI in patients with hypervascularized breast tumors.

Radial scars of the breast and breast carcinomas have similar alterations in expression of factors involved in vascular stroma formation

We recently reported that radial scars are an independent histologic risk factor for breast cancer. The reason for this association is not known. Given the importance of stromal-epithelial interactions in the pathogenesis of breast cancer, we studied radial scars for the expression of a number of factors known to be involved in the formation of vascular stroma in breast cancer. In situ hybridization was performed on formalin-fixed paraffin sections using (35)S-labeled riboprobes for collagen type 1, total fibronectin, extra domain A (ED-A)+ fibronectin, thrombospondin 1, vascular permeability factor (VPF)/vascular endothelial growth factor (VEGF), and one of its endothelial receptors, kinase insert domain-containing receptor (KDR) (vascular endothelial growth factor receptor [VEGFR-2]). Expression levels in radial scars (9 cases) were compared with those in normal breast tissue (15 cases) and infiltrating ductal breast carcinoma (4 cases). Factor VIII-related antigen immunostaining was used to define the distribution of microvessels in radial scars, carcinoma, and normal breast tissue. Compared with normal breast tissue, the radial scars showed focally increased numbers of blood vessels and focally increased expression of messenger RNA (mRNA) for collagen type 1, total fibronectin, ED-A+ fibronectin, thrombospondin 1, VPF/VEGF, and KDR. This pattern of mRNA overexpression was similar to that seen in the 4 invasive cancers. We conclude that there are similarities between radial scars and invasive breast cancers with regard to the level of mRNA expression for several factors involved in the formation of vascular stroma. These results suggest that a similar disturbance in stromal-epithelial interactions is present in both lesions.

Pathobiologic findings in DCIS of the breast: morphologic features, angiogenesis, HER-2/neu and hormone receptors

With the increasing incidence of ductal carcinoma in situ (DCIS) of the breast and its relationship to invasive breast carcinoma, it is important to understand the biology of this entity. We report on a hospital-based survey of 219 case subjects with DCIS of the breast without associated invasive carcinoma diagnosed between 1982 and 1994. The cases of DCIS were analyzed for architectural type, size, nuclear grade, necrosis, calcification, periductal fibrosis, neovascularization, estrogen receptor (ER), progesterone receptor (PR), and HER-2/neu expression. Periductal neovascularization was associated with tumor size, microcalcifications, periductal fibrosis, and HER-2/neu overexpression. Expression of ER and PR was observed in 60 and 62% of the cases, respectively, and HER-2/neu overexpression in 28% of the cases. ER and PR expression were both inversely associated with comedo histology and nuclear grade. HER-2/neu overexpression was positively associated with comedo histology, high nuclear grade, and periductal neovascularization and was inversely correlated with both ER and PR expression. High nuclear grade was positively associated with comedocarcinoma, necrosis, microcalcification, and periductal fibrosis. The role of these molecular/pathologic markers in the biology of DCIS and their potential clinical implications are discussed.

[Evaluation of doppler ultrasonography criteria for the differential diagnosis of pancreatic tumors]

AIM

In order to improve the differential diagnosis of pancreatic lesions, dopplersonographic criteria for the tumours were evaluated.

METHODS

35 patients diagnosed by conventional ultrasound as having a tumour of pancreas were further investigated by B-mode sonography, fundamental and echo-enhanced power-Doppler sonography focusing on specific properties of the tumours. The results were correlated to the histological findings.

RESULTS

Ductal carcinomas and cystadenocarcinomas are often hypovascularized in comparison to the surrounding tissue. In contrast to this, neuroendocrine tumours and cystadenomas are mostly hypervascularized. Tumours associated with pancreatitis show different vascularization patterns depending on inflammation and the extent of necrosis.

CONCLUSIONS

Pancreatic tumours display different vascularization patterns in the echo-enhanced power-Doppler sonography. These characteristics can be useful for the differential diagnosis of pancreatic tumours.

Microvessel quantitation in intraductal and early invasive breast carcinomas

OBJECTIVE

To study the angiogenic process in intraductal carcinoma of the breast, with and without a small focus of stromal infiltration, and to compare the microvessel density between the in situ phase and the early infiltration phases of breast cancer.

STUDY DESIGN

Microvessel density (number of microvessels per square millimeter of neoplasia) was quantitatively evaluated on anti-factor VIII-immunostained histologic sections obtained from 10 ductal carcinomas in situ (DCIS) (category A), 22 DCIS with a small focus of stromal infiltration (category B), 10 microinvasive carcinomas (category C), 12 T1a carcinomas (category D) and 20 T1b carcinomas (category E).

RESULTS

The five categories of lesion had different values for microvessel density (P = .0017). Category A had microvessel density lower than category B (P = .0005). Category B had microvessel density higher than categories C, D and E (P = .0028, .0133 and .0033, respectively).

CONCLUSION

Microvessel density seems to be a feature related to each crucial step in the early phases of neoplastic progression.

[The relationship between laminin-receptor and nm23 protein expression and its correlation with interstitial microvascular density and tumor metastasis in breast carcinoma]

OBJECTIVE

To study the relationship between 67,000 laminin, laminin-receptor (LN-R) and nm23 protein expression, interstitial microvascular density (MVD) and tumor metastasis in breast carcinomas.

METHODS

The expression of laminin (LN), LN-R, FVIIIRAg and nm23 protein were detected in 73 cases of breast carcinoma with immunohistochemical technique and analyzed.

RESULTS

A significant difference in LN expression was found in breast carcinoma according to their pathological grade. A positive relation exists between LN-R expression and lymph node metastasis. A positive relationship exists between the degree of LN-R and MVD expression. A significant difference in lymph node metastasis cases exists between nm23 protein positive expression group and negative expression group. When the expression of nm23 protein was inhibited, the degree of LN-R, MVD expression increased and positively related with lymph node metastasis.

CONCLUSION

LN-R expression enhancement, microvascular density increase and nm23 expression inhibition may be the reliable markers for predicting tumor metastasis and prognosis.

An immunohistochemical analysis of angiogenesis in invasive breast cancer with correlations to clinicopathologic predictors

BACKGROUND

There is evidence that angiogenesis plays an important role in the biologic aggressiveness of breast carcinomas and might be used as a prognostic marker.

MATERIALS AND METHODS

In a series of 140 invasive mammary carcinomas, microvessels were highlighted immunohistochemically using two endothelial markers, factor VIII-related antigen (FVIIIRA) and CD31. Cases were divided into high and low microvessel density groups according to the highest number of microvessels found in each tumour's most vessel-dense part. The data was statistically analysed with regard to classic clinicopathologic prognosticators (i.e., histologic type and grade, nuclear grade, tumour size, stage, lymph node status and steroid receptor immunoexpression) by univariate and multivariate analysis.

RESULTS

Both markers' counts displayed just a weak skewness. Interestingly, CD31 angiogenesis grade was not influenced by any of the prognostic indicators assessed. FVIIIRA immunoreactivity was significantly affected only by nuclear grade (p = 0.041) in logistic regression analysis. Infiltrating lobular carcinomas frequently demonstrated higher FVIIIRA-positive microvessel densities than ductal invasive carcinomas, at least in the subgroup of patients with absence of nodal metastases and in those patients with highly oestrogen-dependent tumours.

CONCLUSIONS

The lack of relation between angiogenesis and either disease stage or lymph node metastasis indicates that this process may be necessary, but not sufficient alone for breast cancer spread.

Vascular stroma formation in carcinoma in situ, invasive carcinoma, and metastatic carcinoma of the breast

The generation of vascular stroma is essential for solid tumor growth and involves stimulatory and inhibiting factors as well as stromal components that regulate functions such as cellular adhesion, migration, and gene expression. In an effort to obtain a more integrated understanding of vascular stroma formation in breast carcinoma, we examined expression of the angiogenic factor vascular permeability factor (VPF)/vascular endothelial growth factor (VEGF); the VPF/VEGF receptors flt-1 and KDR; thrombospondin-1, which has been reported to inhibit angiogenesis; and the stromal components collagen type I, total fibronectin, ED-A+ fibronectin, versican, and decorin by mRNA in situ hybridization on frozen sections of 113 blocks of breast tissue from 68 patients including 28 sections of breast tissue without malignancy, 18 with in situ carcinomas, 56 with invasive carcinomas, and 8 with metastatic carcinomas. A characteristic expression profile emerged that was remarkably similar in invasive carcinoma, carcinoma in situ, and metastatic carcinoma, with the following characteristics: strong tumor cell expression of VPF/VEGF; strong endothelial cell expression of VPF/VEGF receptors; strong expression of thrombospondin-1 by stromal cells and occasionally by tumor cells; and strong stromal cell expression of collagen type I, total fibronectin, ED-A+ fibronectin, versican, and decorin. The formation of vascular stroma preceded invasion, raising the possibility that tumor cells invade not into normal breast stroma but rather into a richly vascular stroma that they have induced. Similarly, tumor cells at sites of metastasis appear to induce the vascular stroma in which they grow. We conclude that a distinct pattern of mRNA expression characterizes the generation of vascular stroma in breast cancer and that the formation of vascular stroma may play a role not only in growth of the primary tumor but also in invasion and metastasis.

Angiogenesis in breast cancer: a comparative study of the observer variability of methods for determining microvessel density

The purpose of this study was to evaluate the reliability of different methods for estimating neovascularization in breast cancer and to compare them in terms of observer variability. The microvessel endothelium was stained immunohistochemically by antibodies against CD34. The investigated methods included Chalkley counting, estimation of intratumoral microvessel density (MVD) by one hot-spot, MVD by the mean value of three hot-spots, and the highest value of MVD in three hot-spots. In addition, we applied stereology in the quantification of angiogenesis in the whole tumor section by random and systematically distributed sampling fields. Each of forty tumors was measured with all methods, twice by the same observer and once by another observer. Observer variation was analyzed by orthogonal regression, estimating the slope and intercepts with 95% confidence intervals (CI), and by analysis of agreement using difference plots. Intraobservationally, the methods had variations of the same magnitude (coefficient of variation [CV] approximately 20%). Interobservationally, the stereologic estimate of vessel profiles, Q(A), from the whole tumor section and the Chalkley counting method had the lowest variation (CV approximately 21%), with a small contribution by observers alone (CV 8% to 9%). Interobservationally, the MVD methods had considerable variation with a large contribution by observers alone (CV approximately 30%), which was lowest using the mean of three hot-spots. Correlation slope and 95% CI of Chalkley were 1.18 (0.95, 1.48), CV 20%; slope of MVD (mean) was 1.14 (0.91, 1.43), CV 31%; and slope of MVD (max) was 1.15 (0.92, 1.45), CV 36%. The slope of MVD on one hot-spot was 1.33 (1.08, 1.63); CV 38%. Additional measurements performed using a conference microscope, eliminating subjectivity in hot-spot selection and field sampling, optimized the reproducibility: slope was 1.02 (0.99, 1.04); CV of differences, 3.5%. On the other hand, reproducibility was not necessarily optimized by choosing the same hot-spot area, because variation in selecting a microscopic field could yield different counting numbers. The stereologic estimation of QA based on the whole tumor section had a high reproducibility, with low variation due to observers. The Chalkley and MVD methods had moderate reproducibility, and the Chalkley method had low variation due to observers alone. For all methods, the biologic variation among patients was the major contributor to the total variation. The Chalkley and MVD methods have been published to provide significant prognostic estimates in breast cancer, but the Chalkley method has less observer variation and may be superior from a methodologic point of view.

Relationships between different measurements of vascularity and clinico-pathological parameters in breast cancer

Microvascular density has been put forward as an independent prognostic factor in breast cancer, with high levels indicating poorer prognosis. However, various studies have failed to confirm its prognostic value. The reasons for the contradictory results are not known, but it is believed that methodological differences are responsible. To test this hypothesis, we have used four different methods of assessing vascularity (average and highest microvascular density, microvascular volume and image analysis of vascular area) and related them to known prognostic factors in 51 cases of breast cancer NOS. All four methods showed a significant correlation with each other, with the exception of image analysis vs microvascular volume. The average microvascular density was significantly lower in p53 positive compared to negative tumours (median 38.4 and 66.2; IQR 31.1 and 49.4, respectively, p < 0.05). Vascularity, measured by the four methods, was not associated with nodal status or any other parameter examined.

Preoperative assessment of tumor angiogenesis by vascular endothelial growth factor mRNA expression in homogenate samples of breast carcinoma: fine-needle aspirates vs. resection samples

BACKGROUND AND OBJECTIVES

Tumor angiogenesis is receiving increased attention as a prognostic factor and also as a possible target for new anticancer agents. We investigated whether extent of vascular endothelial growth factor (VEGF) mRNA expression correlated with degree of neovascularization, and whether this expression in fine-needle aspirates could be a marker for assessing angiogenic potential of breast tumors.

METHODS

VEGF mRNA expression was semiquantitated by reverse transcriptase-polymerase chain reaction (RT-PCR) followed by Southern blotting. Tumor neovascularization was assessed by immunohistochemical staining with anti-CD31 (PECAM) antibody.

RESULTS

There was a positive correlation between degree of neovascularization and semiquantitated VEGF mRNA expression in invasive ductal carcinomas (r2 = 0.346, n = 48, P < 0.05). Extent of VEGF mRNA expression in fine-needle aspirates was closely correlated with that in resected invasive ductal carcinomas equal to or less than 3 cm in size (r2 = 0.874, n = 14, P < 0.05).

CONCLUSION

These data suggest that semiquantitation of VEGF mRNA expression in fine-needle aspirates is useful for assessing angiogenic potential of invasive ductal carcinomas.

[Fast MRI contrast medium dynamics for characterization of tumors. Experiences with functional MR-mammography]

METHODS

MRI studies with high temporal resolution can be achieved with an optimized saturation recovery TurboFLASH sequence, which allows a more detailed characterization of contrast enhancement in tissue as is available with the current FLASH 3D techniques. A two compartment model allows characterization of signal time curves with three parameters, Amp (amplitude), k21 (distribution rate constant) and kel (elimination rate constant).

RESULTS

In a prospective study on 314 patients with indetermined breast lesions signal-time-curves revealed differences in the k21 parameter between benign (0.56 +/- 0.46) and malignant lesions (1.25 +/- 0.80) (p < 0.0001) as well as between different histological classifications.

CONCLUSION

The introduced MR-technique enables a better evaluation of the vascular permeability for the MR contrast media in lesions. Distinct differences were detected, which are influenced by elevated expression of angiogenesis factors such as the vascular endothelial growth factor.

Assessment of tumour vascularity as a prognostic factor in lymph node negative invasive breast cancer

The association between tumour vascularity and relapse was examined in 93 patients with lymph node negative (LNN) invasive breast cancer. Factor VIII-related antibody was used to stain the microvessels. Vascularity was defined by the number of vessels per field counted in the area of highest vascular density at 100 x magnification. These vascular counts were divided into three groups of vascular density (group I: < 67, group 2: 68-100, group 3: > 101 vessels/field). Cross-tabulation analysis revealed a significant relationship between vascular density and tumour grade (P = 0.027). No association was found between vascularity and tumour size, tumour type, age or menopausal status. Survival analysis showed no association between vascularity and relapse-free (P = 0.92) or overall survival (P = 0.99). Significant associations between tumour grade and relapse-free (P = 0.0048) and overall survival (P = 0.0064) and between tumour size at the cut off of 15 mm diameter and relapse-free (P = 0.0097) and overall survival (P = 0.0271) were found. When grade was taken into account the effect of tumour size became non-significant (P = 0.059). Our results suggest that assessment of vascularity is not an independent prognostic factor in LNN invasive breast cancer.

[Does color Doppler complement breast examination?]

Improvements in breast cancer detection are underway with work being done on different imaging techniques and the assessment of abnormal vascularity. In an earlier study we used a 10 MHz CW Doppler pencil probe. In palpable carcinomas 94% had shown abnormal vascularity. However, in nonpalpable lesions, this method did not allow flow detection in combination with imaging. Recent developments in color flow mapping allow detection of small tumor vessels, which are invisible on B-mode ultrasound. Registration of vessels simultaneously to B-mode imaging allows this method to be used for nonpalpable lesions. The sensitivity of diverse Doppler instruments shows remarkable differences. This makes uniform evaluation of the method difficult. We examined 94 symptomatic women using different equipment. In 9 of 32 carcinomas no Doppler signals were found. However, CW Doppler showed low vascularity in these 9 false-negative cases. However, the variation of vascularity in malignancies does not yet allow routine application of this method and needs further scientific evaluation.

Cell proliferation and vascularization in human breast carcinomas

Cell proliferation and vascularization were studied in 10 human breast carcinomas by an immunoenzyme technique. The monoclonal antibody (MAb) Ki-67 was used as a marker for proliferating cells and a polyclonal antibody directed against human von-Willebrand factor to identify blood vessels. The proportion of Ki-67-labelled cells varied from 1% to 20%, the number of small blood vessels from 4.4/mm2 to 57.6/mm2. Within single histological sections of individual tumours the percentage of proliferating cells was not related to the number of small blood vessels. However, after evaluation of 5 sections of each tumour, the average values showed that tumours with a high grade of vascularization had a higher percentage of Ki-67-positive cells than poorly vascularized samples. The influence of vascular density on cell proliferation was investigated in a selected area of one of the tumours (in 2-dimensions) and with regard to the over- and underlying sections (in 3-dimensions). After 2-dimensional evaluation, distances from proliferating cells to the closest blood vessel between 10 and 390 microns were observed, and after 3-dimensional evaluation none of the proliferating cells measured was located more than 130 microns away from the closest vessel.

[Doppler ultrasound differentiation of benign and malignant breast tumors]

Before surgery we studied the blood flow in and around 59 breast tumours (35 malignant and 24 benign) and investigated a correlation with the histology. The most decisive factors were the maximum end-diastolic frequency B (probability greater than magnitude of z = 0.0009) and the mean frequency F mean (probability greater than magnitude of z = 0.0017). The maximum systolic frequency A, the resistance index Ri, the diastolic angle W and the pulsatility index Pi showed less significant differences between malignant and benign histological types. In a retrospective survey, we tried to confirm the definitive histology by our Doppler results. In this, we failed in 17.14%--of malignant cases and in 33.33% in the cases of benign tumours.

The relevance of tumour and surrounding normal tissue vascular density in clinical hyperthermia of locally advanced breast carcinoma

It follows from the present work that the vascularization of the normal tissue present in the treatment volume limits the temperatures achieved during heat treatment of invasive ductal breast carcinoma. The temperatures can often be increased by giving fractionated heat treatment because heat treatment may reduce the cooling capacity of the normal tissue vasculature. Significant damage to supplying vessels occurs at the heat doses necessary to cause necrosis in the tumour and surrounding normal tissue, indicating that secondary cell death is an important mechanism for cell inactivation following hyperthermic treatment of breast carcinoma.

Temperature distribution in locally advanced breast carcinoma during hyperthermic treatment: relationship to perfusion, vascular density, and histology

Temperature distributions achieved during hyperthermic treatment of 16 patients with locally advanced breast cancer were analyzed in relation to tissue perfusion, vascular density, and histology of treated volume. Temperatures were measured using multi-sensor thermistor probes inserted in the center and periphery of the treatment volume. A steady state temperature, Ts, and a perfusion related parameter, PERF, were determined for each probe location. Vascular density and tissue composition were determined by histologic analysis of biopsies taken from the temperature probe locations before treatment. Both malignant and normal tissue were found in the biopsies, reflecting a diffusive tumor growth pattern. The malignant and normal tissue compartments were analyzed separately using stereologic techniques. Ts, PERF, vascular density, and tissue composition differed significantly between patients. There was a clear relationship between Ts and PERF, showing that the local tissue perfusion was decisive for the temperatures achieved. Ts and PERF showed a clear correlation with the normal tissue vascular density, but not with the malignant tissue vascular density; that is, the treatment temperatures achieved were mainly determined by the vascularization of the normal tissue compartment. Fraction of necrosis was the only tissue compartment parameter that showed a clear relationship to Ts and PERF. Ts increased and PERF decreased with increasing necrotic fraction.

Quantitative measurement of monoclonal antibody distribution and blood flow using positron emission tomography and 124iodine in patients with breast cancer

The uptake and in vivo quantitation of monoclonal antibodies (MAbs) has been measured non-invasively using positron emission tomography (PET) and 124iodine in 9 patients with breast ductal carcinoma. Blood-flow measurements were also made using 15oxygen-labelled water and PET to evaluate antibody delivery; 7 patients were studied with HMFGI antibody and 2 patients with a non-specific antibody. Tumour uptake ranged from 2-7.7 x 10(-3)% of injected dose per gram of tissue. Values for normal tissues including liver, lung and bone were also obtained. In 2 out of 7 patients studied with the specific antibody, uptake was greater than that seen with the non-specific antibody. There was no correlation between antibody uptake and blood flow. This report exemplifies the potential of PET for the non-invasive and accurate quantitative assessment of targeted antibody which is a prerequisite to therapy.

Tumor angiogenesis and metastasis--correlation in invasive breast carcinoma

BACKGROUND

Experimental evidence suggests that the growth of a tumor beyond a certain size requires angiogenesis, which may also permit metastasis. To investigate how tumor angiogenesis correlates with metastases in breast carcinoma, we counted microvessels (capillaries and venules) and graded the density of microvessels within the initial invasive carcinomas of 49 patients (30 with metastases and 19 without).

METHODS

Using light microscopy, we highlighted the vessels by staining their endothelial cells immunocytochemically for factor VIII. The microvessels were carefully counted (per 200x field), and their density was graded (1 to 4+), in the most active areas of neovascularization, without knowledge of the outcome in the patient, the presence or absence of metastases, or any other pertinent variable.

RESULTS

Both microvessel counts and density grades correlated with metastatic disease. The mean (+/- SD) count and grade in the patients with metastases were 101 +/- 49.3 and 2.95 +/- 1.00 vessels, respectively. The corresponding values in the patients without metastases were significantly lower--45 +/- 21.1 and 1.38 +/- 0.82 (P = 0.003 and P less than or equal to 0.001, respectively). For each 10-microvessel increase in the count per 200x field, there was a 1.59-fold increase in the risk of metastasis (95 percent confidence interval, 1.19 to 2.12; P = 0.003). The microvessel count and density grade also correlated with distant metastases. For each 10-microvessel increase in the vessel count per 200x field, there was a 1.17-fold increase in the risk of distant metastasis (95 percent confidence interval, 1.02 to 1.34; P = 0.029).

CONCLUSIONS

The number of microvessels per 200x field in the areas of most intensive neovascularization in an invasive breast carcinoma may be an independent predictor of metastatic disease either in axillary lymph nodes or at distant sites (or both). Assessment of tumor angiogenesis may therefore prove valuable in selecting patients with early breast carcinoma for aggressive therapy.

A study on the vascular proliferation in tissues around the tumor in breast cancer

In order to study the vascular proliferation in human breast cancer, blood vessels were counted, per square millimeter, in the tissue immediately around tumors. Mastectomized specimens of 84 patients with breast cancer and specimens from 10 patients with benign mammary diseases were stained by hematoxylin eosin and, where required, by the avidin biotin peroxidase complex method for laminin staining. The vascular density around the breast cancer tissue was 20.35 +/- 8.40/mm2, which was significantly higher than the value of 13.44 +/- 5.85/mm2 for noncancerous mammary tissues (p less than 0.001) or the value of 12.65 +/- 4.12/mm2 for benign mammary disease tissues (p less than 0.01). Among the breast cancers, noninvasive carcinoma had a higher vascular density (28.44 +/- 6.15/mm2) than invasive carcinoma (19.73 +/- 8.22/mm2, p less than 0.02). According to the Japan Mammary Cancer Society Classification of invasive ductal carcinoma, vascularity was higher in the papillotubular type of cancer than in the solid-tubular or scirrhous types of cancer (p less than 0.02), although the papillotubular type had the lowest rate of nodal metastasis and vascular invasion as compared with the scirrhous and solid-tubular types. The vascular density around the tumors did not change in association with an increase in tumor size and it was suggested that blood vessels around a tumor would increase almost in proportion to the square of the tumor diameter.

The application of immunohistochemical stains to identify endothelial-lined channels in mammary carcinoma

The identification of lymphatic and vascular channels with immunohistochemical reagents directed against antigens of the endothelial cells was undertaken in formalin-fixed breast tissues from 100 women with infiltrating mammary duct carcinoma. Fifty women had had lymphatic tumor emboli identified in the original review of their slides. Each case was matched with a control of similar size and laterality. From each case one section containing tumor and normal tissue was stained with antibodies directed against Factor VIII-related antigen, blood group antigen A, blood group antigen B and with Ulex europaeus I agglutinin. All specimens with a reaction displayed variation in the intensity of the stain as well as in the propensity of a given endothelial lined channel to stain at all. Factor VIII-related antigen was identified in 96 tissue samples and Ulex europaeus I agglutinin reacted with 75 specimens. Reactivity of endothelium to blood group antigens either A, B, or both was found in 63 samples. Twenty-one of 26 (81%) samples with endothelial-lined channels which contained tumor emboli in the hematoxylin and eosin (H & E) section showed a reaction to one or more of the reagents. In six other cases involvement of endothelial-lined channels was detected only in the specially stained sections, but in three of these, the tumor emboli appeared only in these deeper sections and could have been detected by serial sections stained with H & E. The results of this study indicate that examination of H & E sections is a reliable method of identifying tumor involvement of endothelial-lined channels. Immunohistochemical stains may be of assistance in occasional cases, but with the reagents currently available this methodology is subject to false-positive and false-negative results.