Lymphatic and angiogenic characteristics in breast cancer: morphometric analysis and prognostic implications

Quantifying Lymphatic Vessel Density in Human Tissue Samples

The development of new blood and lymphatic vessels, through the process of angiogenesis and lymphangiogenesis, respectively, is critical to the development and growth of tumors, and integral to the process of metastasis. Lymphatic vessel density can be assessed as a surrogate measure of lymphangiogenesis in human tissue samples. Lymphatic vessel density has been shown to be associated with lymph node metastasis and patient survival in various solid tumor types. Here we describe a method for quantifying the number of lymphatic vessels within tumor tissue that can also be used to assess lymphatic vessel invasion, and compare with blood vessel density and invasion.

Recent Developments in the Study of the Microenvironment of Cancer and Drug Delivery

Cancer is characterized by disrupted molecular variables caused by cells that deviate from regular signal transduction. The uncontrolled segment of such cancerous cells annihilates most of the tissues that contact them. Gene therapy, immunotherapy, and nanotechnology advancements have resulted in novel strategies for anticancer drug delivery. Furthermore, diverse dispersion of nanoparticles in normal stroma cells adversely affects the healthy cells and disrupts the crosstalk of tumour stroma. It can contribute to cancer cell progression inhibition and, conversely, to acquired resistance, enabling cancer cell metastasis and proliferation. The tumour's microenvironment is critical in controlling the dispersion and physiological activities of nano-chemotherapeutics which is one of the targeted drug therapy. As it is one of the methods of treating cancer that involves the use of medications or other substances to specifically target and kill off certain subsets of malignant cells. A targeted therapy may be administered alone or in addition to more conventional methods of care like surgery, chemotherapy, or radiation treatment. The tumour microenvironment, stromatogenesis, barriers and advancement in the drug delivery system across tumour tissue are summarised in this review.

Mechanisms and Clinical Significance of Tumor Lymphatic Invasion

Tumor-associated lymphatic vessels play an important role in tumor progression, mediating lymphatic dissemination of malignant cells to tumor-draining lymph nodes and regulating tumor immunity. An early, necessary step in the lymphatic metastasis cascade is the invasion of lymphatic vessels by tumor cell clusters or single tumor cells. In this review, we discuss our current understanding of the underlying cellular and molecular mechanisms, which include tumor-specific as well as normal, developmental and immunological processes “hijacked” by tumor cells to gain access to the lymphatic system. Furthermore, we summarize the prognostic value of lymphatic invasion, discuss its relationship with local recurrence, lymph node and distant metastasis, and highlight potential therapeutic options and challenges.

Interleukin-10: A double-edged sword in breast cancer

Breast cancer (BC) is a frequently diagnosed cancer among women worldwide. Currently, BC can be divided into different subgroups according to the presence of the following hormone receptors: estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. Each of these subgroups has different treatment strategies. However, the presence of new metastatic lesions and patient deterioration suggest resistance to a given treatment. Various lines of evidence had shown that cytokines are one of the important mediators of tumor growth, invasion, metastasis, and treatment resistance. Interleukin-10 (IL-10) is an immunoregulatory cytokine, and acts as a poor prognostic marker in many cancers. The anti-inflammatory IL-10 blocks certain effects of inflammatory cytokines. It also antagonizes the co-stimulatory molecules on the antigen-presenting cells. Here, we review the current knowledge on the function and molecular mechanism of IL-10, and recent findings on how IL-10 contributes to the progression of BC.

D2-40 A Helpful Marker in Assessment of Lymphatic Vessel Invasion in Carcinoma of Breast

Background & Objective:

Breast cancer is the most common malignancy among Iranian women and worldwide. Lymphatic vessel invasion (LVI) was found to be an independent prognostic factor in many carcinomas, including invasive carcinoma of the breast. The aim of this study was to compare the hematoxylin and eosin (H&E) staining method and use of the immunohistochemical (IHC) marker ofD2-40, for evaluation of LVI in breast carcinoma specimens.

Methods:

The study was conducted on 50 patients undergone surgery between the years 2010 and 2015 in Rohani Hospital, Babol, Iran with invasive carcinoma of the breast with Census sampling method. LVI was assessed by two surgical pathologists, using H&E- stained sections and two IHC markers, i.e., D2-40 and CD31.

Results:

LVI was detected in 25 (50%) patients by H&E and in 14 (28%) patients by D2-40. Twelve out of 25 patients with positive LVI in H&E were confirmed by D2-40 and 2 out of 25 patients with negative lymphatic vessel in H&E. Only one case showed weak staining of CD31 proving LVI. These results showed a significant difference between the H&E staining and D2-40 IHC study for LVI detection (P=0.004).

Conclusion:

The D2-40 IHC marker is helpful in the diagnosis and confirmation of LVI in invasive carcinoma of the breast. CD31 is not suitable for the evaluation of lymphatic vessels.

Poorer prognosis associated with simultaneous lymphatic and vascular invasion in patients with squamous carcinoma of the thoracic oesophagus

OBJECTIVES

The objective of this study was to demonstrate the cumulative influence of simultaneous lymphatic and vascular invasion in thoracic oesophageal squamous carcinoma after radical operation.

METHODS

A total of 598 cases with thoracic oesophageal squamous carcinoma that were cured by radical open oesophagectomy and extensive lymphadenectomy in the period of 2002 to 2014 were included. An association of the status of lymphovascular invasion with clinicopathological factors and a recurrent pattern was illustrated. Overall survival and disease-free survival were calculated, and the risk factors for decreased disease-free survival were determined with Kaplan-Meier subset analyses and Cox regression analysis.

RESULTS

The status of lymphovascular invasion was significantly associated with tumour differentiation ( P  = 0.045) and the pathological tumour, node and metastasis stage ( P  < 0.001), which includes the tumour intramural invasive depth (T parameter) as well as regional (N parameter) and distant (M parameter) lymph node involvement. The 1-, 3- and 5-year overall survival and postoperative disease-free survival were significantly decreased by lymphatic or vascular invasion alone ( P  < 0.001) and were further decreased by simultaneous lymphatic and vascular invasion ( P  < 0.001). The independent risk factors that predicted reduced disease-free survival were the following: T parameter ( P  < 0.001, odds ratio: 1.436), N parameter ( P  < 0.001, odds ratio: 1.838) and the status of lymphovascular invasion ( P  < 0.001, odds ratio: 1.568). Simultaneous lymphatic and vascular invasion were significantly correlated with postoperative early recurrence ( P  = 0.037).

CONCLUSIONS

Simultaneous lymphatic and vascular invasion independently has a more adverse effect on prognosis than lymphatic or vascular invasion alone. Differentiating between lymphatic and vascular invasion is recommended in order to further study the role of lymphovascular invasion in cancer staging and prognostication in multicentre prospective studies.

The relationship of lymphatic vessel density, lymphovascular invasion, and lymph node metastasis in breast cancer: a systematic review and meta-analysis

Lymph node status is one of the key parameters used for determining the stage of breast cancer progression. The relationship of lymphatic vessel density (LVD), lymphovascular invasion (LVI), and lymph node metastasis (LNM) has not been clearly demonstrated yet. Databases of PubMed, Embase, and Web of Science were searched from inception up to 25 May 2016. Spearman correlation coefficient (r) and 95% confidence interval (CI) were used to determine the relationship within each group. Based on pre-established inclusion criteria, 28 studies involving 2920 breast cancer patients were included in this study. The r values of LVD-LVI, LVD-LNM, and LVI-LNM were 0.45 (95% CI: 0.31 to 0.57), 0.32 (95% CI: 0.23 to 0.40), and 0.24 (95% CI: 0.19 to 0.28), respectively. Compared with intratumoral LVD, peritumoral LVD showed more robust correlation with LVI (r = 0.53, 95% CI: 0.27 to 0.72) and LNM (r = 0.33, 95% CI: 0.18 to 0.46). The patients in LNM positive group presented with higher LVI detection rate of 45.85%, while in LNM negative group with detection rate of 23.85%. The results describe a triangle relationship between LVD, LVI, and LNM in breast cancer. Both LVD and LVI are indicated to be valuable predictors of LNM occurrence. Compared with intratumoral lymphatic vessels, peritumoral lymphatics might be the main disseminate route for breast tumor cells.

The hypoxic tumour microenvironment

Cancer progression often benefits from the selective conditions present in the tumour microenvironment, such as the presence of cancer-associated fibroblasts (CAFs), deregulated ECM deposition, expanded vascularisation and repression of the immune response. Generation of a hypoxic environment and activation of its main effector, hypoxia-inducible factor-1 (HIF-1), are common features of advanced cancers. In addition to the impact on tumour cell biology, the influence that hypoxia exerts on the surrounding cells represents a critical step in the tumorigenic process. Hypoxia indeed enables a number of events in the tumour microenvironment that lead to the expansion of aggressive clones from heterogeneous tumour cells and promote a lethal phenotype. In this article, we review the most relevant findings describing the influence of hypoxia and the contribution of HIF activation on the major components of the tumour microenvironment, and we summarise their role in cancer development and progression.

IL-6 and IL-10 are associated with good prognosis in early stage invasive breast cancer patients

Macrophage-associated cytokines play an important role in cancer metastasis; however, the functions of interleukins (IL) 6 and 10 in breast cancer (BC) progression and metastasis are not clear. In this study the roles of IL-6/IL-10 in regulating vascular invasion and their prognostic significance in BC are investigated. MDA-MB-231 and MCF-7 migration (± IL-6 or IL-10) was assessed by scratch wound assay. Cancer cell adhesion to IL-6/IL-10 stimulated blood and lymphatic endothelial cells (EC) was investigated. Expression of IL-6 /IL-10 was assessed using immunohistochemistry in an annotated cohort of early stage BC (n = 1380) and associations with clinicopathological variables and clinical outcome evaluated. IL-6 did not alter BC cell migration however a dose-dependent inhibition in MDA-MB-231 migration with IL-10 treatment was observed (P = 0.03). BC cells were more adhesive to blood vs lymphatic EC, however, IL-6/IL-10 had no effect on adhesion patterns. High expression of IL-6/IL-10 was associated with clinicopathological criteria (e.g. hormone receptor status, all P < 0.05), improved disease-free survival (DFS; P < 0.05) and improved BC-specific survival (BCSS; only IL-6, P = 0.017). However, neither IL-6 nor IL-10 expression were independent prognostic factors from multivariate analysis. In BC subgroups, IL-6 and IL-10 were good prognosticators in terms of DFS in non-basal, non-triple-negative (non-TN), ER-positive, PgR-positive (only IL-10), and Her-2-negative (only IL-6) BC (all P < 0.05). IL-6 was associated with improved BCSS in non-basal, ER-positive and non-TN BC (all P < 0.05).

Prognostic significance of lymphatic vessel invasion diagnosed by D2-40 in Chinese invasive breast cancers

Lymphatic vessel invasion (LVI) is promising in determining prognosis and treatment strategies, but the application of LVI as a histopathological criterion in breast cancer patients especially those of different subgroups is controversial. This research aims to evaluate the prognostic value of LVI assessed by D2-40 not only in patients with early invasive breast cancer but also in lymph node-negative, lymph node-positive, luminal A-like, luminal B-like, HER2-enriched, and triple-negative subgroups.The study cohort included 255 patients with a median follow-up of 101 months. Immunohistochemical staining for D2-40 was performed to identify LVI.LVI was present in 64 (25.1%), 15 (12.1%), 49 (37.4%), 19 (20.9%), 23 (27.7%), 13 (31.7%), and 9 (22.5%), respectively, in the whole cohort, lymph node-negative, lymph node-positive, luminal A-like, luminal B-like, HER2-enriched, and triple-negative patients. LVI was associated with large tumor size (P = .04), high histological grade (P = .004), involved lymph node (P < .001), and high expression of Ki-67 (P = .003). No significant difference was found among patients with different subtypes and LVI status. The presence of LVI was significantly associated with adverse disease-free survival in the whole cohort (P < .001), lymph node-negative (P < .001), lymph node-positive (P < .001), luminal A-like (P < .001), and luminal B-like patients (P < .001) in both of the univariate and multivariate survival analysis.This study indicated that the presence of LVI stained by D2-40 provided independent prognostic information not only in the whole cohort but also in the subgroup of patients with lymph node-negative, lymph node-positive, luminal A-like, and luminal B-like diseases, which may make a case for routine clinical assessment of LVI using D2-40.

Macrophage-derived interleukin-1beta promotes human breast cancer cell migration and lymphatic adhesion in vitro

Lymphovascular invasion (LVI), encompassing blood and lymphatic vessel invasion, is an important event in tumourigenesis. Macrophages within the tumour microenvironment are linked to the presence of LVI and angiogenesis. This study investigates the role of macrophage-derived, caspase-1-dependent interleukin-1beta (IL-1β) in an in vitro model of LVI. IL-1β significantly augmented the adhesion and transmigration of breast cancer cell lines MCF7 and MDA-MB-231 across endothelial cell barriers. MDA-MB-231 and MCF7 showed a higher percentage of adhesion to lymphatic endothelial cells than blood endothelial cells following endothelial cell IL-1β stimulation (P < 0.001 and P < 0.0001, respectively). Supernatants from activated macrophages increased the adhesion of tumour cells to lymphatic and blood endothelium. Secretion of IL-1β was caspase-1 dependent, and treatment with caspase-1 inhibitor reduced IL-1β production by 73% and concomitantly reduced tumour cell adhesion to levels obtained with resting macrophages. Transmigration of MDA-MB-231 cells across blood and lymphatic endothelial monolayers was significantly increased following IL-1β stimulation. Furthermore, supernatants from activated macrophages increased transmigration of MDA-MB-231 cells across endothelial monolayers, which was abolished by caspase-1 inhibition. IL-1β stimulation of tumour cells significantly increased their migratory ability and a significant increase in migration was observed when MDA-MB-231 cells were stimulated with macrophage conditioned media (two of three donors). Results demonstrate that macrophage production of IL-1β plays an important role in the migration of breast cancer cells and their adhesion to, and transmigration across, blood and lymphatic endothelial cells. Results suggest that IL-1β may play a role in the adhesion to lymphatic endothelial cells in particular.

High lymphatic vessel density and presence of lymphovascular invasion both predict poor prognosis in breast cancer

Background

Lymphatic vessel density and lymphovascular invasion are commonly assessed to identify the clinicopathological outcomes in breast cancer. However, the prognostic values of them on patients’ survival are still uncertain.

Methods

Databases of PubMed, Embase, and Web of Science were searched from inception up to 30 June 2016. The hazard ratio with its 95% confidence interval was used to determine the prognostic effects of lymphatic vessel density and lymphovascular invasion on disease-free survival and overall survival in breast cancer.

Results

Nineteen studies, involving 4215 participants, were included in this study. With the combination of the results of lymphatic vessel density, the pooled hazard ratios and 95% confidence intervals were 2.02 (1.69–2.40) for disease-free survival and 2.88 (2.07–4.01) for overall survival, respectively. For lymphovascular invasion study, the pooled hazard ratios and 95% confidence intervals were 1.81 (1.57–2.08) for disease-free survival and 1.64 (1.43–1.87) for overall survival, respectively. In addition, 29.56% (827/2798) of participants presented with lymphovascular invasion in total.

Conclusions

Our study demonstrates that lymphatic vessel density and lymphovascular invasion can predict poor prognosis in breast cancer. Standardized assessments of lymphatic vessel density and lymphovascular invasion are needed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3338-x) contains supplementary material, which is available to authorized users.

Intratumoral and peritumoral lymphatic vessel density both correlate with lymph node metastasis in breast cancer

The status of lymph node involvement is an important prognostic factor for breast cancer. However, the presence of intratumoral lymphatic vessels in primary tumor lesions and the relationship between lymphatic vessel density (LVD) and lymph node metastasis (LNM) have not been firmly established. Therefore, we performed a meta-analysis study to investigate these issues. According to the pre-established inclusion and exclusion criteria, 13 studies, involving 1029 breast cancer patients, were included in this study. Using immunohistochemical staining, intratumoral lymphatic vessels were detected in 40.07% of breast cancer patients (240/599), and peritumoral lymphatics were detected in 77.09% (397/515). All studies demonstrated that peritumoral LVD was higher than intratumoral LVD, with a pooled standard mean difference and 95% confidence interval (95% CI) of 1.75 (1.28 to 2.21). Both intratumoral LVD and peritumoral LVD positively correlated with LNM, with correlation coefficients of 0.14 (95% CI 0.05 to 0.23) and 0.31 (95% CI 0.13 to 0.49), respectively. In summary, our study reports the overall detection rate of intratumoral lymphatics and demonstrates the associations between intratumoral LVD, peritumoral LVD, and LNM in breast cancer. Additionally, controlled studies with a larger number of subjects are needed to establish these relationships.

Correlation of microvessel parameters in invasive ductal carcinoma of the breast and fibroadenomas: a morphometric study

Modifications of microvascular configuration are essential features encountered during the progression of breast tumors. Our objectives were to correlate morphometrically evaluated microvessel parameters (microvessel density [MVD], microvessel caliber [VC], microvessel cross-sectional area [VCSA], percentage of total VCSA [%TVCSA], and total microvessel boundary density [TVBD]) with histologic grades of invasive ductal carcinoma (IDC) of the breast and benign breast lesions. Sixty cases of IDC presented with modified radical mastectomy, and 20 benign breast fibroadenomas were evaluated for various microvessel parameters, using CD34-immunostained histologic sections by computerized image morphometry. Samples were divided into 4 histologic groups: benign, grade 1, grade 2, and grade 3; mean with SD and range was evaluated for each group. Histologic grades showed a strong positive correlation with %TVCSA (ρ=0.773) and TVBD (ρ=0.811) and a moderate positive correlation with MVD (ρ=0.607), VC (ρ=0.609), and VCSA (ρ=0.616) when analyzed for all samples of the 4 groups. Except MVD, all parameters including age was the lowest (P<.001) for the benign group. Among the IDCs, differences of mean VC and VCSA were not significant; MVD, %TVCSA, and TVBD were the lowest in grade 1 and the highest in grade 3. Upper cutoff value of benign lesions for MVD was 155mm^-2; VC, 9.94μm; VCSA, 94.42 μm²; %TVCSA, 1.33; and TVBD, 4.37mm^-1. Total microvessel boundary density included the information of microvessel concentration and size showed the best correlation with grades. Microvessel density showed a positive correlation with grades in the IDCs, but for the differentiation of benign from malignant, VC, VCSA, %TVCSA, and TVBD showed excellent area under the receiver operating characteristic curve (area under the curve > 0.990), unlike MVD (area under the curve = 0.797).

Tumor lymphangiogenesis and new drug development

Traditionally, tumor-associated lymphatic vessels have been regarded as passive by-standers, serving simply as a drainage system for interstitial fluid generated within the tumor. However, with growing evidence that tumors actively induce lymphangiogenesis, and that the number of lymphatic vessels closely correlates with metastasis and clinical outcome in various types of cancer, this picture has changed dramatically in recent years. Tumor-associated lymphatic vessels have now emerged as a valid therapeutic target to control metastatic disease, and the first specific anti-lymphangiogenic drugs have recently entered clinical testing. Furthermore, we are just beginning to understand the whole functional spectrum of tumor-associated lymphatic vessels, which not only concerns transport of fluid and metastatic cells, but also includes the regulation of cancer stemness and specific inhibition of immune responses, opening new venues for therapeutic applications. Therefore, we predict that specific targeting of lymphatic vessels and their function will become an important tool for future cancer treatment.

Analysis of lymphatic and blood vessel invasion biomarkers in T1 esophagogastric adenocarcinomas for improved patient prognostication

Lymphovascular invasion (LVI) in T1 esophagogastric adenocarcinoma may predict risk of recurrence despite definitive treatment with surgery or endoscopic resection. Podoplanin and CD34 are emerging biomarkers of lymphatic and blood vessel invasion, respectively, and could be adopted to refine LVI assessment. A consecutive series of 65 patients with T1 adenocarcinomas diagnosed at Nottingham University Hospitals were investigated. T1 tumors from 43/65 patients who received primary surgery only were suitable for LVI evaluation by hematoxylin and eosin (H&E) staining as well as by CD34 and Podoplanin immunohistochemistry. LVI was correlated to clinicopathological features and recurrence free survival. H&E staining detected LVI in 11.6% (5/43) of T1 tumors. CD34 and Podoplanin immunohistochemistry significantly improved LVI detection to 25.6% (11/43). Compared with LVI by H&E, immunohistochemical evaluation of blood vessel invasion (CD34) or lymphatic vessel invasion (Podoplanin) was significantly associated with higher grade (P = 0.005), submucosal invasion (T1b) (P = 0.018), lymph node positivity (N1) (P = 0.029) and poor recurrence free survival (P = 0.0003). Our study provides evidence that CD34 and Podoplanin immunohistochemistry could improve LVI detection and allow better prognostication of patients and optimum selection of definitive treatment. Larger multicenter studies are required for further validation that could have significant clinical implications.

Prognostic significance of lymphatic invasion in lymph node-positive breast carcinoma: findings from a large case series with long-term follow-up using immunohistochemical endothelial marker

The poor prognostic significance of lymphatic invasion (LI) in breast carcinoma (BC) as a whole and in lymph node (LN)-negative patients in particular has been recognized in several studies; however, its prognostic role in LN-positive patients is still questionable. Aim of the current study was to assess prognostic role of LI in LN-positive BC specimens. Sections from non-selected 557 LN-positive BC specimens were stained with antibody to podoplanin/D2-40. LI was identified and correlated with clinicopathological features and patients' outcome. Twenty-year overall survival (OS), disease-free interval (DFI), and development of distant metastasis (DM) or recurrence were known for all patients. LI was detected in 262/557 (47%) of specimens ranging from 1 to 350 lesion per tumor section. Its presence was associated with higher grade tumors (P<0.0001), negative hormonal receptors (P<0.0001), high HER-2 expression (P=0.006), and with increased number of positive LNs (P=0.019). In the whole LN-positive BC, presence of LI was a poor prognostic factor for OS, DFI, and development of DM both in univariate and in multivariate analysis. In further stratification of patients, LI was associated with poorer prognosis in patients with single positive LN and not in patients with >1 positive LN. In T1N1 stage, LI was highly associated with poor OS (P=0.002), DFI (P<0.0001), and DM (P<0.0001). In T2N1 patients, LI was associated only with poorer DFI (P=0.037) but not with death or DM. In the two former patient groups, LI lost significance in multivariate analysis. In conclusion, LI is a poor prognostic factor in LN-positive BC particularly for patients having single positive LN. LI therefore would add further prognostic significance when considered in treatment in those patients. We recommend incorporation of LI in breast carcinoma staging and in prognostic indices.

Role of hypoxia-inducible factors in breast cancer metastasis

Human breast tumors contain regions of hypoxia in which cells that are located far from a functional blood vessel have significantly reduced oxygen concentrations when compared with normal mammary tissue. Breast cancer cells adapt to hypoxic conditions by increasing levels of hypoxia-inducible factors (HIFs), which induce the expression of multiple genes involved in angiogenesis, glucose utilization, resistance to oxidative stress, cell proliferation, resistance to apoptosis, invasion and metastasis. Breast cancer patients with increased HIF expression levels in primary tumor biopsies are at increased risk of metastasis. This is an important finding since 90% of breast cancer deaths are the result of metastasis, primarily to the bone, lungs, liver, brain and regional lymph nodes. Although the prognostic significance of reduced oxygen levels in primary breast tumors of cancer patients is well recognized, the mechanisms underlying hypoxia-induced, HIF-dependent breast cancer metastasis are just beginning to be uncovered. Recent studies have implicated HIF target genes in every step of the metastatic process. Drugs, such as digoxin, show the potential therapeutic effects of blocking HIF activity by decreasing primary tumor growth, vascularization, invasion and metastasis in animal models of breast cancer.

Lymphangiogenesis and lymphatic vessel remodelling in cancer

The generation of new lymphatic vessels through lymphangiogenesis and the remodelling of existing lymphatics are thought to be important steps in cancer metastasis. The past decade has been exciting in terms of research into the molecular and cellular biology of lymphatic vessels in cancer, and it has been shown that the molecular control of tumour lymphangiogenesis has similarities to that of tumour angiogenesis. Nevertheless, there are significant mechanistic differences between these biological processes. We are now developing a greater understanding of the specific roles of distinct lymphatic vessel subtypes in cancer, and this provides opportunities to improve diagnostic and therapeutic approaches that aim to restrict the progression of cancer.

Impact of SOX18 expression in cancer cells and vessels on the outcome of invasive ductal breast carcinoma

PURPOSE

SOX18 is a transcription factor known to be involved in hair follicle, blood and lymphatic vessel development, as well as wound healing processes (together with SOX7 and SOX17). In addition, it has been reported that SOX18 may affect the growth of cancer cells in vitro. Until now, the exact role of SOX18 expression in invasive ductal breast carcinoma (IDC) has remained unknown.

METHODS

In this study, we have investigated SOX18 expression in cancer cells and endothelial cells in 122 IDC samples using immunohistochemistry (IHC). SOX18 expression was also determined using real-time PCR and Western blotting in a series of breast cancer-derived cell lines (i.e., MCF-7, BT-474, SK-BR-3, MDA-MB-231, BO2).

RESULTS

Using IHC, we observed SOX18 nuclear expression in cancer cells, as well as in blood and lymphatic vessels of the IDC samples tested. SOX18 expression in the IDC samples correlated with a higher malignancy grade (Grade 2 and Grade 3 versus Grade 1; p = 0.02 and p = 0.009, respectively) and VEGF-D expression (r = 0.27, p = 0.007). SOX18 expression was also associated with HER2 positivity (p = 0.02). A significantly higher SOX18 expression was found in the HER2-positive cell line BT-474, and a significantly lower expression in the triple negative cell lines MDA-MB-231 and BO2. Laser capture microdissection of IDC samples revealed significantly higher mRNA SOX7, SOX17 and SOX18 expression levels in the vessels as compared to the cancer cells (p = 0.02 and p = 0.0002, p < 0.0001, respectively). SOX18 positive intratumoral and peritumoral microvessel counts (MVC) were associated with higher malignancy grades (p = 0.04 and p = 0.02, respectively). Moreover, peritumoral SOX18 positive MVC were found to act as an independent marker for a poor prognosis (p = 0.04).

CONCLUSION

SOX18 expression may serve as a marker for a poor prognosis in IDC.

Lymphatic microvessel density and vascular endothelial growth factor-C and -D as prognostic factors in breast cancer: a systematic review and meta-analysis of the literature

The use of lymphatic microvessel density (LVD) and pro-lymphangiogenic mediators as prognostic factors for survival in breast cancer remains controversial. We searched the electronic databases PubMed and EMBASE without language restrictions for relevant literature to aggregate the survival results. To be eligible, every study had to include the assessment of the LVD or the expression of vascular endothelial growth factor (VEGF)-C or -D in patients with breast cancer and provide a survival comparison, including disease-free survival (DFS) or overall survival (OS), according to the LVD, VEGF-C or VEGF-D status. Across all studies, 56.64 % of patients were considered to have a VEGF-C-positive tumor, and 65.54 % of patients had VEGF-D-positive tumors. High LVD had an unfavorable impact on DFS, with a pooled hazard ratio (HR) of 2.222 (95 % CI 1.579-3.126) and an OS with a HR of 2.493 (95 % CI 1.183-5.25). According to the different lymphatic makers, the subgroup HR in the D2-40 studies was 2.431 (95 % CI 1.622-3.644) for DFS and 4.085 (95 % CI 1.896-8.799) for OS. VEGF-C overexpression, as assessed by immunochemistry, was a prognostic factor for decreased DFS (HR 2.164; 95 % CI 1.256-3.729) and for decreased OS (HR 2.613; 95 % CI 1.637-4.170). VEGF-D overexpression was a significant although weak prognostic factor for DFS only when assessed by immunochemistry, with a HR of 2.108 (95 % CI 1.014-4.384). Our meta-analysis demonstrated that LVD, VEGF-C and VEGF-D could predict poor prognosis in patients with breast cancer. However, standardization of the assessment of LVD and for the expression of lymphangiogenesis factors is needed.

Hypoxia-inducible factor 1-dependent expression of platelet-derived growth factor B promotes lymphatic metastasis of hypoxic breast cancer cells

Lymphatic dissemination from the primary tumor is a major mechanism by which breast cancer cells access the systemic circulation, resulting in distant metastasis and mortality. Numerous studies link activation of hypoxia-inducible factor 1 (HIF-1) with tumor angiogenesis, metastasis, and patient mortality. However, the role of HIF-1 in lymphatic dissemination is poorly understood. In this study, we show that HIF-1 promotes lymphatic metastasis of breast cancer by direct transactivation of the gene encoding platelet-derived growth factor B (PDGF-B), which has proliferative and chemotactic effects on lymphatic endothelial cells. Lymphangiogenesis and lymphatic metastasis in mice bearing human breast cancer orthografts were blocked by administration of the HIF-1 inhibitor digoxin or the tyrosine kinase inhibitor imatinib. Immunohistochemical analysis of human breast cancer biopsies demonstrated colocalization of HIF-1α and PDGF-B, which were correlated with lymphatic vessel area and histological grade. Taken together, these data provide experimental support for breast cancer clinical trials targeting HIF-1 and PDGF-B.

Evaluation of lymphangiogenic factors, vascular endothelial growth factor D and E-cadherin in distinguishing inflammatory from locally advanced breast cancer

BACKGROUND

Inflammatory breast cancer (IBC) is an aggressive form of breast cancer that on presentation resembles locally advanced breast cancer (LABC). This study identified molecular features of IBC and LABC to investigate pathogenesis.

MATERIALS AND METHODS

This study involved 100 IBC cases identified in a national IBC registry and 107 non-IBC LABC cases from the National Cancer Institute's Cooperative Breast Cancer Tissue Resource (CBCTR). Vascular endothelial growth factor D (VEGF-D) and E-cadherin levels and lymphatic vessel density (LVD) measured by podoplanin staining were examined by immunohistochemistry on paraffin-embedded tumor specimens. Intralymphatic tumor emboli (ILTE) were assessed in IBC and non-IBC tumors. IBC cases diagnosed by clinicians but not meeting the case definitions of the American Joint Committee on Cancer (AJCC) or the Surveillance, Epidemiology and End Results (SEER) Program of the National Cancer Institute (NCI)(designated atypical IBC) were compared with AJCC- and/or SEER-defined cases (designated classic IBC).

RESULTS

E-cadherin levels were significantly higher in classic IBC cases compared with non-IBC cases (P = .031), whereas compared with classic IBC, patients with non-IBC LABC had significantly higher LVD (P = .0017) and VEGF-D levels (P < .0001). ILTE was marginally greater in classic IBC than in non-IBC (P = .046). The profile of laboratory values in atypical IBC cases more closely resembled those fitting classic IBC than LABC.

CONCLUSION

E-cadherin levels, LVD, VEGF-D expression, and to a lesser extent, ILTE differed between classic IBC and non-IBC LABC. The similarity of laboratory results between atypical IBC and classic IBC vs. LABC suggests the need for broadening both the AJCC and SEER case definitions for this disease.

Objective assessment of blood and lymphatic vessel invasion and association with macrophage infiltration in cutaneous melanoma

The aims of this study were to investigate the role of vascular invasion (blood and lymphatic), vessel density and the presence of tumour-associated macrophages as prognostic markers in 202 cutaneous melanoma patients. Sections of primary melanoma were stained with lymphatic-specific antibody D2-40 to assess lymphatic vessel invasion and density in intratumoural and peritumoural areas; an antibody against endothelial marker CD34 was used to determine blood vessel invasion and density, and an antibody against CD68 was used to determine macrophage counts. Immunohistochemically determined vascular invasion (combined blood and lymphatic) was compared with that determined using haematoxylin and eosin (H&E) staining. The use of immunohistochemistry increased detection of vascular invasion from 8-30% of patients, and histological exam of H&E-stained tissue was associated with a false positive rate of 64%. Lymphatic vessel invasion occurred at a much higher frequency than blood vessel invasion (27 and 4% of patients, respectively). Although immunohistochemically detected vessel invasion was significantly associated with histological markers of adverse prognosis, such as increased Breslow thickness, ulceration and mitotic rate (all P<0.001), no associations with relapse-free or overall survival were observed. High macrophage counts were significantly associated with markers of aggressive disease, such as Breslow thickness, ulceration and mitotic rate (P<0.001, P<0.001, P=0.005, respectively), and lymphatic vessel invasion and high microvessel density (P=0.002 and P=0.003, respectively). These results suggest that vascular invasion is more accurately detected using immunohistochemistry and occurs predominantly via lymphatic vessels. The association of vessel characteristics with histological characteristics of the primary melanoma provides evidence for their biological importance in melanoma, but that they were not associated with clinical outcome attests to the value of existing histological prognostic biomarkers. We note that a high macrophage count may be associated with neovascularisation and primary tumour growth, and may also promote invasion through lymphatic vessels.

Clinicopathological correlation of cutaneous metastatic breast carcinoma using lymphatic and vascular markers: lymphatics are mainly involved in cutaneous metastasis

Precise clinicopathological correlations of the clinical features of metastatic breast carcinoma with lymphatic-specific markers are rare. We classified 28 patients with metastatic breast carcinoma according to their clinical features. Immunohistochemical staining was performed using D2-40, CD31 and CD34. Of the 28 patients, 8 (28.6%) had inflammatory metastatic carcinoma, 6 (21.4%) had the telangiectatic type, 5 had the nodular type, 3 had the en cuirasse type, 3 had alopecia neoplastica, and 3 had a combination of features. D2-40 staining revealed dilated lymphatic channels (lymphangiectasia) in the upper dermis of all patients; in addition, 13 patients (46.4%) had intralymphatic tumour-cell emboli, which were common in those with the inflammatory and telangiectatic types. Intratumoral lymphatic invasion in the main tumour nodule was seen in 12 patients (42.9%). Our results suggest that cutaneous metastatic breast carcinomas have various clinical presentations, and that lymphatic vessels play an important role in all types of cutaneous metastasis.

Angiogenesis: a prognostic determinant in pancreatic cancer?

Angiogenesis has been associated with disease progression in many solid tumours, however the statement that tumours need angiogenesis to grow, invade and metastasise seems no longer applicable to all tumours or to all tumour subtypes. Prognostic studies in pancreatic cancer are conflicting. In fact, pancreatic cancer has been suggested an example of a tumour in which angiogenesis is less essential for tumour progression. The aim of the present study was therefore to measure angiogenesis in two anatomically closely related however prognostically different types of pancreatic cancer, pancreatic head and periampullary cancer, and investigate its relation with outcome. Vessels were stained by CD31 on original paraffin embedded tissue from 206 patients with microscopic radical resection (R0) of pancreatic head (n=98) or periampullary cancer (n=108). Angiogenesis was quantified by microvessel density (MVD) and measured by computerised image analysis of three randomly selected fields and investigated for associations with recurrence free survival (RFS), cancer specific survival (CSS), overall survival (OS) and conventional prognostic factors. MVD was heterogeneous both between and within tumours. A higher MVD was observed in periampullary cancers compared with pancreatic head cancers (p<.01). Furthermore, MVD was associated with lymph node involvement in pancreatic head (p=.014), but not in periampullary cancer (p=.55). Interestingly, MVD was not associated with RFS, CSS or with OS. In conclusion, angiogenesis is higher in periampullary cancer and although associated with nodal involvement in pancreatic head cancer, pancreatic cancer prognosis seems indeed angiogenesis independent.

Lymphatic and blood vessels in basal and triple-negative breast cancers: characteristics and prognostic significance

Basal and triple-negative breast cancer phenotypes are characterised by unfavourable biological behaviour and outcome. Although certain studies have examined their pathological and molecular profile, the vascular characteristics of lymphatic and blood vessels have not been examined. Immunohistochemical staining with podoplanin, CD34 and CD31 was used to examine lymphatic and microvessel density, as well as vascular invasion in 197 basal-like and in 99 triple-negative breast tumours and compared against 200 non-basal and 334 non-triple-negative cases. All specimens were lymph node negative. Vascular invasion was identified as blood or lymphatic vascular invasion by the differential expression of markers. All measurements were correlated with clinicopathological features and prognosis. No significant difference was detected between the basal and triple-negative groups in terms of lymphatic or microvessel density or vascular invasion. However, both the basal and the triple-negative groups showed significantly higher microvessel density than did the non-basal and non-triple-negative groups (P=0.017 and P<0.001, respectively). Unlike microvessel density, no significant difference was detected in lymphatic density between the basal or triple-negative groups compared with their respective controls. Interestingly, vascular invasion, almost entirely lymphatic invasion, was detected in 27% of the basal and in 26% of the triple-negative groups with no significant difference in comparison with control groups. In both basal and triple negatives, vascular invasion was associated with poorer survival by univariate and multivariate analyses. The 20-year overall survival rate in basal-like tumours was 55% in vascular invasion-positive cases compared with 73% in vascular invasion-negative tumours (P=0.012), and 46% in triple-negative vascular invasion-positive compared with 79% in vascular invasion-negative tumours (P=0.001). Basal-like vs non-basal-like and triple-negative vs non-triple-negative tumours have similar vascular characteristics in terms of lymphatic vessel density and vascular invasion but higher microvessel density, suggesting that such groups may preferentially benefit from anti-angiogenic therapy. Vascular invasion was, in all phenotypes, almost entirely lymphatic vessel invasion and could stratify basal-like and triple-negative phenotypes into distinct prognostic groups.

Incomplete inside-out growth pattern in invasive breast carcinoma: association with lymph vessel invasion and recurrence-free survival

Invasive micropapillary carcinoma (IMPC) is a rare subtype of epithelial tumor of the breast listed in the 2003 World Health Organization histologic classification of tumors of the breast. It is characterized by inside-out micropapillary morphology, frequent lymph vessel invasion (LVI), and lymph node metastasis; however, its etiology remains unknown. This study investigated the incomplete inside-out growth pattern (IGP) in invasive ductal carcinoma, not otherwise specified (NOS), and examined the association between incomplete IGP and clinicopathologic features, including the presence of intratumoral lymph vessels (ILV), LVI, nodal metastasis, and prognosis. Tumor tissues from 166 invasive duct carcinomas NOS and 10 IMPCs were immunostained using an anti-epithelial membrane antigen antibody to detect IGP and with D2-40 antibody to determine the presence of ILV and LVI. Incomplete IGP was detected focally in 88 (53%) of 166 invasive duct carcinomas NOS. Transition areas between IMPC and invasive duct carcinoma NOS also showed prominent incomplete IGP in 9 (90%) of 10 IMPCs. Incomplete IGP in invasive duct carcinomas NOS was associated with larger tumor size, higher frequencies of ILV, LVI, nodal metastasis, and poorer recurrence-free survival by univariate analysis. Incomplete IGP, ILV, and tumor size independently affected LVI by multivariate analysis. These findings indicate that incomplete IGP of tumor cell clusters is not uncommon and is a useful tool for predicting LVI in invasive duct carcinoma NOS of the breast.

Histopathological subclassification of triple negative breast cancer using prognostic scoring system: five variables as candidates

We attempted to subclassify triple negative breast cancer (TNBC) cases into subgroups according to clinical outcome or prognosis of TNBC patients using archival specimens. We analyzed 102 Japanese cases of invasive TNBC who underwent surgery between January 1998 and December 2007. The clinicopathological factors and clinical information were retrospectively retrieved from reviewing the charts of the patients. Immunohistochemical staining was performed for estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor 1 (EGFR1), CK5/6, CK14, Ki-67, and CD31 for microvessel density (MVD). Median follow-up time of the patients was 68.5 months. Multivariable analysis demonstrated that pathologic node status was the most significantly associated with relapse-free survival (RFS) and breast cancer-specific survival (BCSS) of these patients. Pathological tumor size, basal-like type, Ki-67 labeling index (LI) and MVD were also independently associated with RFS and BCSS. Based on these results, we devised the risk score system reflecting hazard ratios of these prognostic factors above. With this system, TNBC patients in this study were classified into three subgroups (low-risk group: score 0-3, intermediate-risk group: score 4-7 and high-risk group: score 8-10). The significant difference of RFS and BCSS was detected among these three different subgroups of the patients (p < 0.05). We propose the risk score system, which incorporated pathologic nodal status, size of the primary tumor, the presence or absence of basal-like features, Ki-67 LI, and MVD in order to predict postoperative clinical course of the Japanese TNBC patients.

Lymphangiogenesis and lymphatic metastasis in breast cancer

Lymphatic metastasis is the main prognostic factor for survival of patients with breast cancer and other epithelial malignancies. Mounting clinical and experimental data suggest that migration of tumor cells into the lymph nodes is greatly facilitated by lymphangiogenesis, a process that generates new lymphatic vessels from pre-existing lymphatics with the aid of circulating lymphatic endothelial progenitor cells. The key protein that induces lymphangiogenesis is vascular endothelial growth factor receptor-3 (VEGFR-3), which is activated by vascular endothelial growth factor-C and -D (VEGF-C and VEGF-D). These lymphangiogenic factors are commonly expressed in malignant, tumor-infiltrating and stromal cells, creating a favorable environment for generation of new lymphatic vessels. Clinical evidence demonstrates that increased lymphatic vessel density in and around tumors is associated with lymphatic metastasis and reduced patient survival. Recent evidence shows that breast cancers induce remodeling of the local lymphatic vessels and the regional lymphatic network in the sentinel and distal lymph nodes. These changes include an increase in number and diameter of tumor-draining lymphatic vessels. Consequently, lymph flow away from the tumor is increased, which significantly increases tumor cell metastasis to draining lymph nodes and may contribute to systemic spread. Collectively, recent advances in the biology of tumor-induced lymphangiogenesis suggest that chemical inhibitors of this process may be an attractive target for inhibiting tumor metastasis and cancer-related death. Nevertheless, this is a relatively new field of study and much remains to be established before the concept of tumor-induced lymphangiogenesis is accepted as a viable anti-metastatic target. This review summarizes the current concepts related to breast cancer lymphangiogenesis and lymphatic metastasis while highlighting controversies and unanswered questions.

Lymphangiogenic characteristics of triple negativity in node-negative breast cancer

PURPOSE

Triple-negativity breast cancer (TNBC), being negative for the estrogen receptor, the progesterone receptor, and the human epidermal growth factor receptor 2, represents a subgroup of breast cancer with a poor clinical outcome. The aim of the study was to determine whether TNBC is associated with lymphangiogenesis in node-negative breast carcinomas.

METHODS

The authors investigated the clinicopathologic characteristics, lymphatic vessel density (LVD), and expression of 2 lymphangiogenic factors, vascular endothelial growth factor C (VEGF-C) and vascular endothelial growth factor D (VEGF-D), in 21 lymph node-negative TNBCs and 70 lymph node-negative non-TNBCs.

RESULTS

TNBC correlated with younger age (below 35 year) and higher histological grade. It also correlated with a higher intratumoral and peritumoral LVD, positive lymphatic invasion, and positive VEGF-C and VEGF-D expression.

CONCLUSIONS

For the first time, this study indicated a link between triple-negativity breast cancer and lymphangiogenesis. Lymphangiogenesis might help explain the special malignant phonotype of breast cancer, and lymphangiogenesis inhibitors might be a novel choice for triple-negativity breast cancer patients.

Breast cancer metastasis to the stomach resembling early gastric cancer

Breast cancer metastases to the stomach are infrequent, with an estimated incidence rate of approximately 0.3%. Gastric metastases usually are derived from lobular rather than from ductal breast cancer. The most frequent type of a breast cancer metastasis as seen on endoscopy to the stomach is linitis plastica; features of a metastatic lesion that resemble early gastric cancer (EGC) are extremely rare. In this report, we present a case of a breast cancer metastasis to the stomach from an infiltrating ductal carcinoma (IDC) of the breast in a 48-year-old woman. The patient had undergone a left modified radical mastectomy with axillary dissection nine years prior. A gastric endoscopy performed for evaluation of nausea and anorexia showed the presence of a slightly elevated mucosal lesion in the cardia, suggestive of a type IIa EGC. A histological examination revealed nests of a carcinoma in the subepithelial lymphatics, and immunohistochemical staining for estrogen receptor was positive. This is an extremely rare case with features of type IIa EGC, but the lesion was finally identified as a cancer metastasis to the cardia of the stomach from an IDC of the breast.