Endothelial cell proliferation and vascular patterns in urothelial carcinoma.

INTRODUCTION: The bladder cancer has some characteristics: the sixth most incident neoplasm in the United States, the majority of diagnosed cases in those 55 years of age and older, four times more common in man than women, a reduced five-year survival rate in case of metastatic disease. Despite the beneficial effects of the combination therapy and immunotherapy, the low response rate and drug resistance were reported. The main goal of this work was evaluation of the endothelial cell proliferation from urothelial carcinomas. PATIENTS, MATERIALS AND METHODS: Fifty-two cases of T2-T4 infiltrative bladder tumors, aged between 46 and 78 years, were investigated. Morphological, simple and cluster of differentiation 31 (CD31)∕Ki67, CD31∕smooth muscle actin (SMA) double immunostaining were performed. RESULTS: In all the analyzed infiltrative bladder tumors, three types of vessels were noticed: immature, intermediate and mature. In the central part of the tumor area, the following distribution of vessel types was noticed: immature (62.25%), intermediate (35.1%), and mature vessels (2.65%). In the peripheral tumor area, the intermediate vessels increase numerically, up to 54% and the mature ones, up to 18.6%. The peritumoral area was characterized by the absence of immature vessels and the presence of intermediate and mature ones only. It was found the presence of endothelial cell nuclei stained for Ki67 only for immature and intermediate vessels, and never for mature ones. CONCLUSIONS: The vascular patterns may contribute to a better stratification of the patient subgroups and antiangiogenic treatment algorithms.

Chloride Intracellular Channel Protein 1 Expression and Angiogenic Profile of Liver Metastasis of Digestive Origin.

Chloride intracellular channel 1 (CLIC1) is involved in cell migration and metastasis. The histological growth patterns of liver metastasis are as follows: desmoplastic (d-HGP), replacement (r-HGP), pushing (p-HGP), and mixed. The aim of this study was to evaluate the relation between HGP, angiogenesis, and CLIC1 expression. Materials and Methods: A total of 40 cases of primary tumors and their LM: d-HGP (12 cases), r-HGP (13 cases), and p-HGP (15 cases), were evaluated through simple and double immunostaining. CLIC1 assessment was conducted as follows: scores of 0 (less than 10% of positive cells), 1 (10-30%), 2 (30-50%), or 3 (more than 50%) were assigned. Heterogeneous CLIC1 expression was found. CLIC1 in primary tumors correlated with grade G for all cases of LM with a p-HGP (p = 0.004). The CLIC1 score for LMs with an r-HGP correlated with grade G of the corresponding primary tumor (p = 0.027). CLIC1 and CD34+/Ki67+ vessels (p = 0.006) correlated in primary tumors. CLIC1 in primary tumors correlated with CD34+/Ki67+ vessels of LMs with a d HGP (p = 0.024). Conclusions: The CLIC1 score may have prognostic value, mainly for LMs with a p-HGP and r-HGP, and therapeutic value for LMs with a d-HGP.

Profile and Potential Significance of Dendritic Cells in Head and Neck Squamous Cell Carcinoma.

BACKGROUND/AIM: The aim of the study was the analysis of immunohistochemical expression of S100 protein and CD1a by dendritic cells (DCs) from head and neck squamous cell carcinoma (HNSCC), correlation with the histological grade, as well as analysis of the potential significance of antigen-presenting cells according to tumor location. PATIENTS AND METHODS: Samples were collected from 50 patients with HNSCC, conventionally stained with hematoxylin and eosin for pathological diagnosis and grade, followed by immunohistochemical evaluation with S100 protein and CD1a expression. RESULTS: The correlation of S100 expression in DCs with histological grading was significant (p=0.049). We also observed a correlation between CD1a expression and histological grading (p=0.016). DCs density was predominantly intratumoral for both CD1a (63% of cases) and S100 protein expression (25% of cases). CONCLUSION: Our results demonstrated the association of DCs with histological grade. Their intratumoral infiltration suggests their potential antitumor role.

The mast cell reaction in premalignant and malignant lesions of the head and neck.

Head and neck squamous cell carcinoma (HNSCC) is one of the most frequent and aggressive neoplasms of this anatomical region. Many studies evaluated the neoplastic cells, but few works focused on the tumor microenvironment. In the present study, we investigated the distribution and mast cell density (MCD) in malignant and premalignant lesions of the oral cavity, tongue, pharynx, and larynx. There were analyzed 52 specimens of HNSCC, and 15 biopsies taken from patients with dysplasia. Results were compared with those found in a control group of 10 biopsies of oral mucosa from patients with inflammatory diseases. Slides stained with Hematoxylin-Eosin were used for the histopathological diagnosis and grade, and mast cells (MCs) were identified by immunohistochemistry, using anti-MC tryptase. MCs were counted using a method similar to that proposed for microvessel density. We found a significant increase in the number of MCs from the normal oral mucosa until overt carcinoma. Unlike normal tissues, in HNSCC, many MCs were found between tumor cells. We found no relationship between MCs and blood vessels in the tumor area. A significant statistical correlation was found between dysplastic and malignant tumors, but not between tumors with a different grade. Also, it was not found relationship between MCD and the anatomical location of the tumor. Based on these results, we believe that MCD evaluated by anti-MC tryptase is an independent factor of prognosis and reflects an unfavorable outcome.

The molecular profile of breast cancer: primary tumor versus corresponding lymph node metastases.

Breast cancer (BrCa) is the most frequent malignancy in female, and lymph node metastases (LNM) is an important prognostic and therapeutic parameter. The molecular classification is nowadays largely applied to characterize the primary tumors, but few studies focused on the comparison between the molecular profiles of the primary with corresponding LNM. In the current work, we investigated the expression of conventional markers used by molecular classification in both primary tumors and axillary LNM. A series of 156 patients with BrCa was investigated, and from these 80 cases showed LNM. After routine pathological investigation, including the histopathological form and grade, we performed additional step sections from the primary and lymph nodes for immunohistochemistry. All procedures for hormone receptors, human epidermal growth factor receptor 2 (HER2), Ki67, cytokeratin 5 (CK5), epidermal growth factor receptor (EGFR), p53, E-cadherin, and B-cell leukemia∕lymphoma-2 (Bcl-2) were performed using the standard automated procedures. We found significant differences between the primary tumors and corresponding LNM in luminal A, luminal B, and basal-like carcinoma. No phenotypical interconversions were noticed in HER2 and unclassified BrCa. Our data demonstrate that in almost 20% of the cases the molecular profile of the primary does not overlap with aspects found in the lymph nodes. Our results strongly suggest performing the molecular classification in both primary tumors and in LNM. Current data suggest that the application of this diagnostic procedure will significantly influence the therapeutic strategy.

Mast cell density in the primary tumor predicts lymph node metastases in patients with breast cancer.

Breast cancer (BrCa) is the most frequent neoplastic disease in female, with high morbidity and mortality. Most of the researches were focused on tumor cells concerning their natural evolution, molecular profile, and potential response to therapy. Few and uncertain data are available about the tumor microenvironment and its impact on the progression of the disease. Mast cells (MCs) associated to BrCa have been reported many years ago, but their real and specific role in the biology of this disease remained elusive. In the current study, we have investigated the predictive role of MCs from the primary tumor on lymph node metastasis on patients stratified based on the molecular classification. We investigated 156 patients with BrCa, stratified as luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) type, basal-like, and unclassified. MCs were identified with anti-MC tryptase antibody in a double immunohistochemical reaction combined with anti-cluster of differentiation 34 (CD34) antibody. Mast cell density (MCD) was calculated based on the hot-spot method, on three fields with maximum density of MCs in each case. The final result was the arithmetic media that was compared with the molecular profile and lymph node metastases. We found no significant correlation between MCD and the molecular profile of the primary tumor, but we noticed a strong correlation between intratumor MCD and lymph node metastases, regardless of the molecular type.

Proliferating Lymphatic Endothelial Cells as a Prognostic Marker in Head and Neck Squamous Cell Carcinoma.

Podoplanin and Ki-67 are two important markers of cancer progression. The aim of this study is to evaluate double immunostaining for Ki-67 and podoplanin in head and neck squamous cell carcinoma (HNSCC), and to observe the involvement of lymphagiogenesis in tumoral and peritumoral areas, as well as the density of tumor proliferation correlated with histopathological grading. A total of 50 patients with HNSCC were included in this study. We carried out a morphological evaluation of tissue samples, after that, cases were selected for double Ki-67 and podoplanin immunostaining. Podoplanin expression was significantly correlated with histopathological grade (p < 0.05; p = 0.037) and expression of Ki-67 (p < 0.05; p = 0.050). A high expression of podoplanin, as well as of the proliferation factor Ki-67, was observed in histopathological grade G3 and the correlation between these (p < 0.05; p = 0.028), and implication of LMVD and LVI was not significant (LMVD p = 0.577; LVI p = 0.976). This study demonstrated the importance of double immunolabeling in assessing lymphagiogenesis and tumor proliferation in correlation with histopathological grades in HNSCC.

Loss of E-Cadherin Expression Correlates With Ki-67 in Head and Neck Squamous Cell Carcinoma.

BACKGROUND/AIM: The aim of the study was to evaluate the correlation between the rate of proliferation and immunohistochemical expression of E-cadherin, and their predictive role in patients with head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: Samples were collected from 50 patients with HNSCC, and the expression of Ki-67 and E-cadherin was evaluated by immunohisto-chemistry (IHC). Previously, samples were conventionally stained with haematoxylin and eosin for histological diagnosis and grade. RESULTS: High E-cadherin expression was predominantly associated with less differentiated tumours (p<0.5; p=0.0305). Also, we observed a significant correlation between Ki-67 expression in tumour cells and tumour grade (p=0.0245). A strong correlation was noticed between low E-cadherin expression, increased Ki-67-proliferation rate and advanced T2-T3 tumour stage (p=0.0242). CONCLUSION: In this study we showed that Ki-67 proliferation rate and E-cadherin expression are important features in patients with HNSCC. Therefore, higher Ki-67 index values correlate with loss of E-cadherin expression, which indicates a poorer prognosis. These aspects support the use of both Ki-67 and E-cadherin as prognostic markers in specimens from patients with HNSCC.

Patterns of Tumor Vasculogenesis on a Chick Embryo Chorioallantoic Membrane In Vivo Model of Breast Cancer.

BACKGROUND/AIM: Understanding tumor vasculogenesis is a cornerstone for the inhibition of tumor progression. This study aimed to generate an in vivo breast cancer environment to analyze the patterns of tumor vasculogenesis. MATERIALS AND METHODS: Human mesenchymal stem cells (hMSC) and breast cancer MCF-7 cells (MCF-7) were seeded onto a chorioallantoic membrane (CAM) and, after a 7-day incubation, we performed a morphological and immunohistochemical analysis of CAM. RESULTS: hMSC and MCF-7 activated vasculogenesis and hematopoiesis on CAM. They stimulated the development of cord/capillary-like structures (CLS), formed by endothelial-like cells and hematopoietic cells. CLS presented a polygonal pattern, evolving towards a clearly visible plexus. Immunohistochemically, CLS were CD105+/AC133+/Oct3/4+, and the intensity was weak-moderate in the endothelial-like cells (inconstant) and weak in the hematopoietic cells. CONCLUSION: Tumor and embryonic vasculogenesis share a common paradigm, while CD105, AC133, and Oct3/4 were found to play a role in establishing the vasculogenic and hematopoietic stage.

CLIC1 Expression in Skin Biopsies from Patients With Rheumatoid and Psoriatic Arthritis as a Potential Tool to Predict Therapy Response.

BACKGROUND/AIM: Chloride intracellular channel protein 1 (CLIC1) activates inflammasomes in rheumatoid (RA) and psoriatic (PsA) arthritis. We studied CLIC1 expression in RA and PsA patients' skin with vasculitis and its variability depending on the therapy used. MATERIALS AND METHODS: CLIC1 immunoexpression was evaluated in the vascular (CLIC1-V) and stromal (CLIC1-S) compartments of the RA and PsA skin biopsies of patients treated with methotrexate (MTX), leflunomid (LFN), corticotherapy (CT), or biological therapies. RESULTS: MTX significantly reduced CLIC1-S expression (p=0.016), whereas LFN decreased CLIC1-V (p<0.001). LFN therapy duration also correlated with CLIC1-V (p<0.001). CT decreased CLIC1-S expression (p=0.006). CLIC1-S expression persisted in skin biopsies despite of erythrocyte sedimentation rate (ESR, p=0.018) and C reactive protein (CRP, p=0.0026) normalisation. For PsA, CLIC1-S expression significantly related to MTX (p<0.022). Both CLIC1-S (p<0.001) and CLIC1-V (p=0.007) decreased by biological therapies in RA. CONCLUSION: CLIC1 expression is strongly influenced by the therapy used. Our data strongly support the extensive evaluation of CLIC1 in RA as a potential marker of inflammation and tool to predict therapy response.

Chloride Intracellular Channel Protein 1 (CLIC1), E-cadherin and P-cadherin Define Distinct Subclasses of HER2, Luminal B and Triple-negative Breast Cancer.

BACKGROUND/AIM: Chloride intracellular channel protein (CLIC1), E- and P-cadherin (Ecad, Pcad) are certified factors of aggressivity, but they have not been studied in breast cancer to date. The aim was to study CLIC1, Ecad and Pcad impact on breast cancer in terms of defining new high-risk subgroups. MATERIALS AND METHODS: Ninety-seven breast cancer biopsies were immunohistochemically evaluated for CLIC1, Ecad and Pcad expression related to molecular subtypes. CLIC1 expression was assessed in both tumor cells (CLIC1T) and blood vessels (CLIC1V). RESULTS: For 23% of Luminal A cases, both cadherins and CLIC1V were positive. Luminal B/HER2 subtype, had two specific phenotypes: Ecad-/Pcad-/CLIC1T-/CLIC1V+ and Ecad+/Pcad-/CLIC1T-/CLIC1V+. All TNBC cases were clustered into two subgroups: 60% were Ecad+/Pcad+/CLIC1T+/CLIC1V+) while 40% were Ecad+/Pcad+/CLIC1T+/CLIC1V-). CONCLUSION: CLIC1, Ecad and Pcad association stratifies molecular types of breast cancer in subgroups that may explain different response to therapy and different aggressiveness previously observed by other authors within the same molecular subtype.

Chloride Intracellular Channel Protein 1 (CLIC1) Ιs Over-expressed in Muscle Invasive Urinary Bladder Cancer.

BACKGROUND/AIM: Invasive bladder cancer mortality remains high despite progresses made in early diagnosis and surgical procedures. Thus, there is a need to define new markers for bladder cancer. CLIC1 has not been previously studied in bladder cancer and thus, we aimed to assess its immunohistochemical expression in relation to different stages of bladder cancer development. MATERIALS AND METHODS: Immunohistochemistry for CLIC1 was applied in 50 cases of muscle invasive bladder cancer. RESULTS: CLIC1 was not expressed in the normal urothelium, but a strong reaction was observed in dysplastic urothelium, carcinoma in situ and in 94% of the cases with invasive urothelial carcinoma; however, it was not expressed in squamous cell carcinoma cases. No correlation was found between the immunohistochemical expression of CLIC1 and the stage and grade of the tumour. CONCLUSION: CLIC1 was overexpressed in urinary bladder dysplastic epithelium, carcinoma in situ and invasive carcinoma. CLIC1 constitutes a new potential marker of invasive bladder cancer.

Differential Expression of E-Cadherin and P-Cadherin in Breast Cancer Molecular Subtypes.

BACKGROUND/AIM: E- and P-cadherin (E-cadh, P-cadh) control tumor cell invasion, metastatic or stemness potential and chemotherapy resistance. The study aimed to assess E- and P-cadherin expression in breast cancer molecular subtypes. MATERIALS AND METHODS: Immunohistochemistry for E-cadh and P-cadh was performed for 97 breast cancer cases. Membrane (M), cytoplasmic (C) or mixed (MC) patterns of E-cadh and P-cadh were considered in our evaluation. RESULTS: E-cadh and P-cadh C pattern was significantly correlated in the HER2 subtype (p=0.031). P-cadh M pattern was highly specific for the HER2 subtype (p=0.002). Only P-cadh C characterized the triple negative breast cancer subtype (p=0.015). For Luminal B/HER2 cases, P-cadh M pattern was strongly coexpressed with the E-cadh MC pattern (p=0.012). Progesterone receptor (PR) expression influenced E-cadh M pattern in the Luminal B/HER2 subtype (p=0.042). CONCLUSION: E- and P-cadherins define distinct subgroups within breast cancer molecular subtypes. Our findings support the inclusion of E- and P-cadherin into breast cancer molecular classification.

The Mesenchymal-Epithelial and Epithelial-Mesenchymal Cellular Plasticity of Liver Metastases with Digestive Origin.

BACKGROUND: Few data are available regarding the epithelial to mesenchymal transition (EMT) /mesenchymal to epitheilal transition (MET) in the liver metastasis of digestive cancers. The aim of this study was to establish EMT/MET metastatic tumor cell plasticity according to the histological growth pattern of liver metastases. MATERIALS AND METHODS: Biopsies from 25 patients with liver metastasis (desmoplastic, replacement and pushing type) were evaluated. Double immunostaining of E-cadherin/vimentin, keratin 8,18/vimentin and E-cadherin/ keratin 8,18 were performed. RESULTS: The following cell types were noted: epithelial, mesenchymal, non-differentiated and differentiated hybrid mesenchymal/ epithelial and non-hybrid phenotype. All cases had mesenchymal/ epithelial phenotype cells. A significant correlation was found between the non-differentiated hybrid mesenchymal/ epithelial phenotype metastatic cells and histological growth pattern for gastric and colorectal cancer. CONCLUSION: A MET-targeting strategy, in conjunction with conventional chemotherapy, may be useful for the treatment of liver metastases.

The "game" of glial fibrillary acidic and S100 proteins in pituitary adenomas: two players or several?

INTRODUCTION: S100 protein and GFAP expression in pituitary adenomas tumour cells is not well known; few correlations with other prognostic or therapeutic factors have previously been reported in pituitary adenomas. We aim to elucidate their involvement in the pathogenesis of pituitary adenomas and to establish the correlation of their expression with different growth factors and growth factor receptors known to have a prognostic and/or therapeutic role. MATERIAL AND METHODS: Sixty-one cases of pituitary adenomas were immunohistochemically assessed for the expression of GFAP and S100 protein in both tumour cells and FS cells, in close relationship with hormone profile, and correlated with vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) expression, previously studied by our team. RESULTS: GFAP and S100 protein were expressed both in tumour cells and FS cells. Differences between morphology, distribution, and density of GFAP+ FS cells and S100+ FS cells were observed according to the hormone profile of pituitary adenomas. GFAP and S100 protein expression in tumour cells was significantly related to hormone profile of pituitary adenomas and also with VEGF and EGFR expression. CONCLUSIONS: GFAP and S100 protein expressions in tumour cells from pituitary adenomas are influenced by hormone profile. Our re-sults support the presence of two molecular subtypes of FS cells GFAP+/VEGF+/S100 respectively and another one that is GFAP-/S100+/EGFR+ simultaneously with the classical variant GFAP+/S100+. It is possible that S100+/EGFR+ pituitary adenomas represent a group of pituitary adenomas with an aggressive behaviour and a high ability of invasion and recurrence.

Adipose Tissue Graft Improves Early but not Late Stages of Nerve Regeneration.

AIM: The aim of the study was to assess the effect of autologous fat graft on nerve regeneration by means of immunohistochemistry. MATERIALS AND METHODS: The rat sciatic nerve was used; complete transection followed by primary neurorrhaphy was performed on both hind legs, on the left side a processed fat graft was applied, surrounding the nerve. Nerve biopsies were collected and immunohistochemical procedures were performed for glial fibrillary acidic protein (GFAP) and for neurofilament-associated protein(NFAP). RESULTS: At 4 weeks, GFAP-positive cells were observed in the connective tissue formed between the two nerve endings on the left side only. At 10 weeks, GFAP-positive structures were present and exhibited a tendency to become linear on both sides, with an increased density on the left. NFAP-positive expression was present in the left treated limb with a disorganized pattern. CONCLUSION: Adipose tissue led to the stimulation of GFAP-positive Schwann cells, which could have a positive impact on nerve regeneration in the clinical setting.

High Ki-67 expression is associated with prolactin secreting pituitary adenomas.

Pituitary adenomas represent the third most common primary intracranial tumor in neurosurgical practice. To understand the biological behaviour of the pituitary adenomas previous studies have determined the tumor proliferation rate using monoclonal antibodies targeted against the Ki-67 antigen. The aim of this study was to correlate the Ki-67 index with hormonal profiles of pituitary adenomas. The study included 50 pituitary adenomas. For histopathologic evaluation, the sections were stained with routine hematoxylin and eosin method. Additional paraffin sections from each tumor were immunostained using primary antibodies against the following pituitary hormones: somatotropin (STH), prolactin (PRL), adrenocorticotrophic hormone (ACTH), thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH). To detect the expression of Ki-67 we used a mouse anti-human monoclonal antibody (clone K2). The percentage of Ki-67 positive nuclei (Ki-67 labeling index) was assessed by counting approximately 1000 nuclei of the tumor cells at ×400 magnification. Out of the 50 tumor samples, 31 (62%) pituitary adenomas showed proliferative activity, and the proliferation rate was variable in this group. The overall mean Ki-67 labeling index was 1.59 ± 1.47, ranging from 0.3% to 6.6%. In 5 cases, the Ki-67 index was >3%, all of them being prolactinomas. The Ki-67 index was higher in PRL-secreting adenomas (mean ± SD was 3.37 ± 1.80, range 0.9 - 6.6%). Our study provides the evidence that a higher Ki-67 value is associated with pituitary adenomas that secrete PRL (prolactinomas and mixed STH/PRL-secreting adenomas).

The multifaceted role of podoplanin expression in hepatocellular carcinoma.

The role of podoplanin in hepatocellular carcinoma (HCC) is not clear yet. The aim of our study was to evaluate the expression of podoplanin in HCC and to determine its role in hepatocarcinogenesis. We performed immunohistochemistry with monoclonal D2-40 antibody, on paraffin-embedded tissue sections of 72 patients diagnosed with HCC. Lymphatic vessels density (LVD) was increased in patients who had vascular invasion at the time of diagnosis (P=0.018) and in those with associated cirrhosis (P=0.006). Tumor cells showing podoplanin expression were correlated with histological grade (P=0.040). Podoplanin-expressing cancer associated fibroblasts (CAFs) were correlated with both LVD (P=0.019) and tumor cells (P=0.015). Our results sustain the dual role of podoplanin in HCC by its involvement in both HCC tumorigenesis, lymphatic neovascularization and tumor invasion invasiveness. A possible crosstalk between epithelial and stromal tumor cells in HCC tumor microenvironment may be mediated by podoplanin, but this hypothesis needs further studies to elucidate this interrelation.

Inhibition of Notch signaling induces extensive intussusceptive neo-angiogenesis by recruitment of mononuclear cells.

Notch is an intercellular signaling pathway related mainly to sprouting neo-angiogenesis. The objective of our study was to evaluate the angiogenic mechanisms involved in the vascular augmentation (sprouting/intussusception) after Notch inhibition within perfused vascular beds using the chick area vasculosa and MxCreNotch1(lox/lox) mice. In vivo monitoring combined with morphological investigations demonstrated that inhibition of Notch signaling within perfused vascular beds remarkably induced intussusceptive angiogenesis (IA) with resultant dense immature capillary plexuses. The latter were characterized by 40 % increase in vascular density, pericyte detachment, enhanced vessel permeability, as well as recruitment and extravasation of mononuclear cells into the incipient transluminal pillars (quintessence of IA). Combination of Notch inhibition with injection of bone marrow-derived mononuclear cells dramatically enhanced IA with 80 % increase in vascular density and pillar number augmentation by 420 %. Additionally, there was down-regulation of ephrinB2 mRNA levels consequent to Notch inhibition. Inhibition of ephrinB2 or EphB4 signaling induced some pericyte detachment and resulted in up-regulation of VEGFRs but with neither an angiogenic response nor recruitment of mononuclear cells. Notably, Tie-2 receptor was down-regulated, and the chemotactic factors SDF-1/CXCR4 were up-regulated only due to the Notch inhibition. Disruption of Notch signaling at the fronts of developing vessels generally results in massive sprouting. On the contrary, in the already existing vascular beds, down-regulation of Notch signaling triggered rapid augmentation of the vasculature predominantly by IA. Notch inhibition disturbed vessel stability and led to pericyte detachment followed by extravasation of mononuclear cells. The mononuclear cells contributed to formation of transluminal pillars with sustained IA resulting in a dense vascular plexus without concomitant vascular remodeling and maturation.

Unusual bilateral cervical metastases as first clinical evidence of lung cancer.

We report on an unusual case of laterocervical bilateral metastatatic masses with unknown clinical, radiological or computer tomographicic detected primary site of origin. Cancer of an unknown primary site is a clinical syndrome, accounting for 2%-5% of patients with cancer. The peculiarities of our case are its evolution as fast-growing bilateral tumor masses with involvement of other neck structures and its unexpected origin from the lung, certified by complementary immunohistochemical tests following surgery, in the absence of any other clinical signs or any detectable lung tumor mass by radiological or computer tomographic tests.