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At least 1,603 records · Page 89Linked to original sources
PubMed1991

Perivascular sympathectomy does not remove adrenergic nerves from distal vessels. The effect of various denervations on the rat saphenous bundle: a histochemical study.

It has been claimed earlier that perivascular sympathectomy removes distal adrenergic innervation of the vessels. Based on preliminary results suggesting the contrary, the purpose of this work was to reconsider the denervation effect of perivascular sympathectomy. We operated on 40 rats using different denervation methods mainly to test the effects of perivascular sympathectomy on the distal saphenous vessels of the leg. The operations were performed on the right leg, while the left leg was used as a control. Samples were taken 2 days after the operations for glyoxylic acid-induced fluorescence examination for the histochemical demonstration of adrenergic nerves. Perivascular sympathectomy seemed to remove the adrenergic innervation only from the operated segment of the vessel. There was a short segment of diminished innervation a few millimeters in length just distal to the perivascular sympathectomy while the more distal adrenergic nerves around the vessels appeared to be normal. When the saphenous nerve was cut the adrenergic innervation seemed to disappear for 1 cm and to continue to be diminished at the medial malleolus site. Lumbar sympathectomy did not seem to remove the distal adrenergic nerves around the vessels, but caused only a slight decrease in innervation. It can be concluded that the peripheral adrenergic innervation is apparently normal after perivascular sympathectomy and that the operation does not have the previously assumed denervation effects.

Adrenergic Fibers↗
PubMed1984

Morphology of endoneurial blood vessels of frog sciatic nerve during vascular perfusion.

In order to determine if increased injection pressures can alter the permeability and ultrastructure of blood vessels of the frog blood-nerve barrier, these vessels were examined following perfusion of the iliac artery at rates of 0.21 or 0.82 ml/min. At either perfusion rate, endoneurial blood vessel profiles were clearly evident and the surface area of these vessels amounted to 60% of the surface area of the perineurium. In all vessels a large number of vesicles were present within the endothelial cells. Many were attached by necks to one or the other plasma membrane, but no transcellular channels were evident. At the higher flow rate no changes in vesicles or junctions were seen, but blebs and blisters were evident at the luminal membranes of the endoneurial endothelium. When microperoxidase was perfused at 0.82 ml/min, reaction product frequently flooded the endothelial cells, was found as clumps on the cell surface, and was distributed within the endoneurial space. These changes represent the only ultrastructural evidence of endothelial cell damage and altered permeability in response to increased rate of perfusion.

Animals↗
PubMed1983

Prostacyclin producing activity of human umbilical, placental and uterine vessels.

Prostacyclin-like material producing activity of umbilical, placental and uterine vessels was studied. Umbilical arteries and veins were separated at sites 10-15cm and 1-2cm from insertion of the umbilical cord to the placenta. Placental arteries and veins were prepared from the first, second and third branches on the chorionic plate. Uterine vessels were obtained at abdominal hysterectomy. After incubation of each specimen in Tris buffer 1 ml (pH8.5, 0.5M) for 30 min at room temperature, the inhibitory effect of the medium on ADP induced platelet aggregation was measured and the prostacyclin-like material was quantified. These procedures were repeated consecutively four times in total for each specimen. Prostacyclin-like material production rate and its total production were calculated. In total prostacyclin-like material production, umbilical arteries and veins were much higher than placental arteries and veins respectively (p less than 0.001), but there was no significant difference between placental and uterine vessels. These results showed that prostacyclin-like material producing activity of blood vessels declined remarkably at the transitive region from umbilical to placental vessels. It seems that this distribution of vascular prostacyclin-like material producibility in the fetoplacental vascular system correlates with that of vascular reactivity to prostacyclin.

Adult↗
PubMed1987

Nerve fibers surrounding intracranial and extracranial vessels from human and other species contain dynorphin-like immunoreactivity.

Dynorphin B(20-32) was visualized by immunohistochemistry in guinea-pig and rat perivascular nerve fibers and was measured by radioimmunoassay within the walls of feline, canine, bovine and human cephalic and systemic arteries and veins. Canine vessels contained the highest levels. When human blood vessels or trigeminal ganglia were subjected to reverse-phase high-performance liquid chromatography, dynorphin immunoreactivity exhibited a retention time identical to that of synthetic dynorphin B. No differences in dynorphin-like immunoreactivity were measurable between feline systemic arteries and veins, or between cephalic and systemic vessels. The highest amounts were present in leptomeninges devoid of large pial arteries. Relatively high levels were also measured in feline and human trigeminal ganglia and feline superior cervical and sphenopalatine ganglia, three sources of projecting perivascular axons. Levels did not diminish, however, in ipsilateral feline cephalic vessels following either unilateral trigeminal or superior cervical ganglionectomies. Hence, dynorphin-containing fibers may project from parasympathetic cell bodies or perhaps from intrinsic brain sources. Previously published reports indicate that the kappa agonist dynorphin does not modify vessel tone when added in vitro but does inhibit release of neurotransmitters from afferent and sympathetic axons via prejunctional receptors. These observations suggest a pharmacological role for dynorphin on sensory and autonomic functions of the vasculature.

Aged↗
PubMed1992

Abrupt vessel closure complicating coronary angioplasty: clinical, angiographic and therapeutic profile.

To assess the clinical, angiographic and procedural correlates of outcome after abrupt vessel closure during coronary angioplasty, results were analyzed of 109 patients (8.3%) who had abrupt vessel closure during 1,319 consecutive coronary angioplasty procedures performed between July 1, 1988 and June 30, 1990. These 109 patients had a mean age of 59 +/- 11 years; 63% were male, 57% had had a prior myocardial infarction and 61% had multivessel disease. Coronary angioplasty was performed in the settings of acute myocardial infarction (14%), recent myocardial infarction (36%), unstable angina (34%) and stable ischemia (29%). Abrupt vessel closure occurred at a median of 27 min (range 0 min to 5 days) from the first balloon inflation. By angiographic criteria, thrombus or coronary dissection was identified in 20% and 28% of cases, respectively; both thrombus and dissection were present in 7% of closures, and 45% were due to indeterminate mechanisms. Successful reversal of abrupt vessel closure, defined as restoration of normal Thrombolysis In Myocardial Infarction (TIMI) grade 3 flow without resultant Q wave myocardial infarction, emergency bypass surgery or death, was achieved in 47 patients (43%). By hierarchal analysis, the incidence of death, emergency coronary bypass surgery, Q wave and non-Q wave myocardial infarction was 8%, 20%, 9% and 11%, respectively. Univariate analysis using 23 clinical, morphologic and procedural variables demonstrated that successful outcome after abrupt closure was associated with prolonged balloon inflations (greater than 120 s) (odds ratio = 6.87, p less than 0.001), unstable angina (odds ratio = 2.37, p = 0.034) and placement of an intracoronary stent (odds ratio = 5.33, p = 0.062). By multivariate analysis, independent correlates of successful outcome were prolonged balloon inflations (odds ratio = 5.11, p = 0.001) and intracoronary stenting (odds ratio = 4.37, p = 0.049). Thus, although prolonged balloon inflations and intracoronary stents may improve outcome after abrupt vessel closure, the cumulative risk of morbidity or mortality remains significant and mandates investigation into improved strategies for its prevention and treatment.

Acute Disease↗
PubMed1994

Contrast-enhanced intravascular ultrasound: validation of a new technique for delineation of the vessel wall boundary.

OBJECTIVES: We evaluated a new technique for delineation of the vessel wall surface during intravascular ultrasound imaging using echogenic contrast agents. BACKGROUND: Intravascular ultrasound is used for detection of complex vessel wall structures after catheter-based interventions; however, differentiation between the lumen and these wall structures can be difficult. METHODS: In 12 anesthetized dogs, intracoronary ultrasound was performed during intracoronary bolus injection (3 and 6 ml) of different contrast agents (hand-agitated saline solution, standard iohexol, sonicated iohexol, hand-agitated iohexol, SHU 454, SHU 508). Contrast intensity was quantified by videodensitometry, and contrast homogeneity was assessed qualitatively (grade 0 to 3). RESULTS: Peak contrast intensities for SHU 454 and SHU 508 (mean [+/- SD] 48 +/- 9 and 36 +/- 6 U, respectively) were higher compared with standard, sonicated or agitated iohexol (16 +/- 3, 28 +/- 7 and 20 +/- 3 U, respectively) or with agitated saline solution (17 +/- 4 U); intensities were higher for 6 ml compared with that for 3 ml. Contrast homogeneity was higher for SHU 508 (mean [+/- SD] 3.0 +/- 0) and SHU 454 (2.7 +/- 0.5) compared with the other agents (standard iohexol 1.2 +/- 0.4, sonicated iohexol 2.0 +/- 0.5, agitated iohexol 1.8 +/- 0.6, agitated saline solution 1.0 +/- 0.4). Exact delineation of the vessel wall surface was possible in 100% of SHU 508 and in 88% of SHU 454 injections compared with 13% of agitated iohexol and 8% of sonicated iohexol injections. Accurate surface delineation was never achieved with standard iohexol or agitated saline solution. Shadowing of parts of the vessel wall by contrast material occurred at peak intensity of 75% of SHU 508 and 46% of SHU 454 injections but not with the other agents. No adverse physiologic reactions were noted, except for transient negative inotropic effects after 6 ml of SHU 508. CONCLUSIONS: This preliminary study shows that delineation of the vessel wall boundary using echogenic contrast agents during intravascular ultrasound is safe and feasible. Because of higher contrast intensity and homogeneity, SHU 454 and SHU 508 are superior to other agents.

Animals↗
PubMed2004

Does refractive error influence the association of blood pressure and retinal vessel diameters? The Blue Mountains Eye Study.

PURPOSE: To determine if refractive errors influence the association of blood pressure and retinal vessel diameters. DESIGN: Population-based, cross-sectional study. METHODS: Retinal photographs from the right eyes of participants (n = 3,654, aged 49+ years) in the Blue Mountains Eye Study taken during baseline examinations (1992 to 1994) were digitized. The diameter of all retinal vessels located half to one disk diameter from the disk margin was measured using a computer-assisted imaging program. These measurements were combined to provide the average diameters of retinal arterioles and venules of that eye, and the ratio of their diameters, the arteriole-to-venule ratio (AVR). The association of blood pressure and retinal vessel diameters was analyzed before and after correction for refraction using the Bengtsson formula. RESULTS: Before correction, each 10-mm Hg increase in mean arterial blood pressure was associated with a 3.7-microm (95% confidence interval [CI], 3.2-4.3) decrease in arteriolar diameter and a 0.9-microm (95% CI, 0.3-0.9) decrease in venular diameter. After correction for refraction, each 1-mm Hg increase in mean arterial blood pressure was associated with a 3.7-microm (95% CI, 3.2-4.2) decrease in arteriolar diameter and a 0.8-microm (95% CI, 0.3-0.9) decrease in venular diameter. Refraction was not associated with the AVR and had no effect on the association of blood pressure and AVR. CONCLUSION: Refraction had no appreciable effect on the association of blood pressure and retinal vessel diameters or on the AVR. Correction for refraction is important for quantifying absolute retinal vessel caliber, but may not be particularly important in epidemiologic studies investigating the association of generalized retinal arteriolar narrowing and hypertension.

Aged↗
PubMed2005

Influence of vessel diameter on the efficacy of distal protection devices during saphenous vein graft intervention.

We sought to determine the influence of vessel diameter on the efficacy of distal protection devices during saphenous vein graft intervention. From the Filterwire EX Randomized Evaluation trial, in which patients who underwent saphenous vein graft stenting were randomized to distal protection with the GuardWire or FilterWire EX, outcomes in 572 patients were examined in vessel size tertiles. The 30-day composite incidence of major adverse cardiac events (MACEs) increased with vessel size and was 6.9%, 9.7%, and 14.9% in the smallest, middle, and largest tertiles, respectively (p = 0.04). MACE rates were relatively vessel size independent for the GuardWire but increased steadily with vessel size with the FilterWire EX. In the smallest tertile, MACEs were reduced by 71% with the FilterWire EX compared with the GuardWire (p = 0.05), with the devices showing similar event rates in the other tertiles.

Aged↗
PubMed2005

Role of neural guidance signals in blood vessel navigation.

Despite the tremendous progress achieved in both vasculogenesis and angiogenesis in the last decade, little is still known about the molecular mechanisms underlying the pathfinding of blood vessels during their formation. However, emerging evidence shows that different axonal guidance cues, including members of the Slit and semaphorin families, are also involved in the blood vessel guidance, suggesting that blood vessels and nerves share common mechanisms in choosing and following specific paths to reach their respective targets. These promising findings open novel avenues not only in vascular biology but also in therapeutic angiogenesis. Indeed, the identification of new molecules involved in the guidance of blood vessels may be helpful in designing angiogenic strategies, which would insure both the formation of new blood vessels and their guidance into an organized and coordinated network.

Animals↗
PubMed2005

Engineering blood vessels from stem cells: recent advances and applications.

Endothelial cells organized into blood vessels are critical for the formation and maintenance of most tissues in the body and are involved in regulating physiological processes such as angiogenesis, inflammation and thrombosis. Endothelial cells are of great research interest, because of their potential to treat vascular diseases and to stimulate the growth of ischaemic tissue. They can be used to engineer artificial vessels, repair damaged vessels, and to induce the formation of vessel networks in engineered tissues. For such clinical applications, proliferating human endothelial progenitor cells can be isolated from adult tissues or embryonic stem cells. Recently, these cells were successfully used to engineer single vessels and to stimulate capillary networks, both in vitro and in vivo.

Animals↗
PubMed2004

Coronary stenting versus balloon angioplasty in small vessels: a meta-analysis from 11 randomized studies.

OBJECTIVES: A meta-analysis of 11 randomized trials was done to compare stenting versus balloon angioplasty (BA) in small coronary vessels. BACKGROUND: Randomized studies on coronary stenting (CS) in small vessels have yielded controversial results. METHODS: Eleven randomized trials on CS versus BA in small vessels, including angiographic re-evaluation at six months, were analyzed. RESULTS: The BeStent (Medtronic Instent, Minneapolis, Minnesota) was used in four studies, the Multi-Link (Guidant, Advanced Cardiovascular Systems Inc., Santa Clara, California) in three trials, and the NIR (Boston Scientific Corp., Boston, Massachusetts), JoStent (Jomed International AB, Helsingborg, Sweden), Tenax (Biotronik, Berlin, Germany), and BioDivysio (Abbott Vascular Devices, Redwood City, California) in the remaining four trials. Overall, 3,541 patients were included (1,672 allocated to BA and 1,869 to stent). The rate of cross-over from balloon to stent in the pooled population was 19%, and unsuccessful stent deployment occurred in 2% of the patients allocated to stent. The pooled rates of restenosis were 25.8% and 34.2% in patients allocated to stent and balloon, respectively (p = 0.003) (risk ratio [RR] 0.77; 95% confidence interval [CI] 0.65 to 0.92). A smaller reference vessel diameter at baseline was associated with a higher risk reduction in the restenosis rate (y = -3.551 + 1.826 [x]; p = 0.012). Patients allocated to stent had lower rates of major adverse cardiac events (15.0% vs. 21.8%, p = 0.002; RR 0.70; 95% CI 0.57 to 0.87) and new target vessel revascularizations (12.5% vs. 17.0%, p = 0.004; RR 0.75, 95% CI 0.61 to 0.91). CONCLUSIONS: Elective stenting is superior to provisional stenting in small coronary arteries. This benefit is more evident in smaller coronary arteries.

Angioplasty, Balloon↗
PubMed2004

Development of rapid staining protocols for laser-capture microdissection of brain vessels from human and rat coupled to gene expression analyses.

Laser-capture microdissection (LCM) is a technique that enables selective extraction of desired cells from heterogeneous tissues compatible with subsequent molecular analyses. The specific visualization of desired cell types prior to LCM is essential for achieving selective capture. We have developed rapid and selective staining protocols for LCM extraction of microvessels from human and rat brain. Vessels in human and rat brain sections were visualized by a 2 min exposure to fluorescein-labeled lectins Ulex Europeaus Agglutinin I (UEA I) and Ricinus Communis Agglutinin I (RCA I), respectively. Immunohistochemical staining for the endothelial-specific marker, Factor VIII-related antigen (FVIII-rAg), co-localized with that for either UEA I or RCA I, confirming the selective staining of vascular structures with these lectins. Both brain vessels and perivascular parenchyma were captured using LCM, followed by RNA isolation. RT-PCR analyses demonstrated the enrichment of LCM-captured vessels and parenchyma in FVIII-rAg and GFAP mRNA, respectively. LCM-captured human vessels also expressed the tight junction-specific gene, zonula occludens 1 (ZO-1). LCM extraction of vessels from brain sections can be used to perform molecular fingerprinting of neurovascular unit in various brain pathologies.

Animals↗
PubMed2006

Exogenous pro-angiogenic stimuli cannot prevent physiologic vessel regression.

BACKGROUND: In healing wounds, rising levels of vascular endothelial growth factor (VEGF) induce a period of robust angiogenesis. The levels of pro-angiogenic factors in the wound begin to decline just before a period of vascular regression, suggesting that these mediators are necessary to sustain vessel density. The purpose of this study was to determine if the maintenance of pro-angiogenic stimuli in the wound would prevent physiological vessel regression. MATERIALS AND METHODS: A standard subcutaneous sponge wound model was modified by the addition of a mini-osmotic pump, allowing manipulation of the wound milieu by the addition of exogenous growth factors. After initial characterization of this model, exogenous VEGF (10 microg/mL), FGF (10 microg/mL), PDGF (10 microg/mL), or VEGF (10 microg/mL) plus FGF (10 microg/mL) were delivered to wounds and blood vessel density analyzed by immunohistochemistry. RESULTS: VEGF administration resulted in a transient increase in wound vessel density (P < 0.05). None of the pro-angiogenic growth factors (VEGF, FGF, PDGF, VEGF/FGF) were able to prevent vascular regression (P = NS). CONCLUSIONS: These findings suggest that the anti-angiogenic signals that mediate physiological vascular regression in wounds are strongly dominant over pro-angiogenic stimuli during the later phases of wound healing. Clinical manipulation of anti-angiogenic signals in addition to the currently used pro-angiogenic targets may be needed to achieve therapeutic modulation of blood vessel density.

Analysis of Variance↗
PubMed2004

Endothelium properties of a tissue-engineered blood vessel for small-diameter vascular reconstruction.

PURPOSE: A tissue-engineered blood vessel (TEBV) produced in vitro by the self-assembly method was developed in our laboratory for the replacement of small-diameter blood vessels. The interior of this vessel is covered by an endothelium. The aim of the present study was to evaluate whether the endothelial layer would make a favorable contribution at the time of implantation of the TEBV by investigating in vitro the hemocompatible properties of the endothelial cells covering its interior. METHODS: The secretion of the von Willebrand factor (vWF) and expression of thrombomodulin by the endothelium were assessed, and the adhesive molecules E-selectin and intercellular adhesion molecule-1 (ICAM-1) were quantified as a function of maturation time. To evaluate the functional response of the endothelium on injury, the cellular response to physiological stimulatory factors (thrombin and lipopolysaccharide [LPS]) was analyzed. RESULTS: The endothelial cells formed a confluent monolayer displaying favorable hemocompatible properties (78% +/- 10% of cells expressing thrombomodulin with only 12 +/- 3 mU/10(6) cells of vWF secreted over a 2-hour period), which acquired their full expression after a culture period of 4 days. Moreover, pro-adhesive properties toward inflammatory cells were not observed. The cells were also able to respond to physiological-stimulating agents (thrombin and LPS) and demonstrated a statistically significant overexpression of the corresponding molecules under the conditions tested. CONCLUSIONS: These results indicate that the endothelium of the tissue-engineered blood vessel produced by the self-assembly approach displays advantageous qualities with regard to the vessel's future implantation as a small-diameter vascular prosthesis.

Blood Vessels↗
PubMed2005

Artificial blood vessel: the Holy Grail of peripheral vascular surgery.

Artificial blood vessels composed of viable tissue represent the ideal vascular graft. Compliance, lack of thrombogenicity, and resistance to infections as well as the ability to heal, remodel, contract, and secrete normal blood vessel products are theoretical advantages of such grafts. Three basic elements are generally required for the construction of an artificial vessel: a structural scaffold, made either of collagen or a biodegradable polymer; vascular cells, and a nurturing environment. Mechanical properties of the artificial vessels are enhanced by bioreactors that mimic the in vivo environment of the vascular cells by producing pulsatile flow. Alternative approaches include the production of fibrocollagenous tubes within the recipient's own body (subcutaneous tissue or peritoneal cavity) and the construction of an artificial vessel from acellular native tissues, such as decellularized small intestine submucosa, ureter, and allogeneic or xenogeneic arteries. This review details the most recent developments on vascular tissue engineering, summarizes the results of initial experiments on animals and humans, and outlines the current status and the challenges for the future.

Animals↗
PubMed2006

The human erythrocyte has developed the biconcave disc shape to optimise the flow properties of the blood in the large vessels.

The human erythrocyte adopts a distinctive biconcave disc form in vivo. The question as to why the red blood cell should have this particular profile remains unresolved. It has been suggested that this shape maximises the surface area to volume ratio and thus expedites diffusion. This hypothesis, however does not stand up to examination. Maximal diffusion occurs in the small vessels. In order to pass through the microvasculature the erythrocyte becomes distorted and deviates from the biconcave disc shape [Branemark PI, Lindstrom J. The shape of circulating blood corpuscles. Biorheology 1963;1:139; Guest MM, Bond TP, Cooper RG, Derrick JR. Red blood cells: change in capillaries. Science 1963;142:1319-21]. Here, it is suggested the haemodynamic factors have dictated the peculiar shape of the discocyte. The deleterious nature of turbulent flow on the cardiovascular system suggests that the biconcave disc form has evolved out of a necessity to maximise laminar flow, minimise platelet scatter which in turn suppress atherogenic activity in the large vessels [Yoshizumi M, Abe J, Tsuchiya K, Berk BC, Tamaki T. Stress and vascular responses: athero-protective effect of laminar fluid shear stress in endothelial cells: possible and mitogen-activated protein kinases. J Pharmacol Sci 2003;9:172-6]. The biconcave profile of the discocyte means that much of the mass is distributed in the periphery. This increases the moment of inertia of the cell and subsequently renders the erythrocyte less prone to rotation during flow in the large vessels. Here it is suggest that this reduction in rotation promotes laminar flow and discourages platelet scattering by minimising the "Eddy currents" and it thus anti-atherogenic. A number of pathological mutations result in the red blood cell adopting a spherical shape as opposed to the biconcave disc profile. The sphere has a smaller moment of inertia when compared to the discocyte, as much of the mass is distributed round the centre. The spherocyte is hence much more prone to rotation during flow in the large vessels. There is evidence to suggest that asplenic individuals suffering from spherocytosis are at increased risk of atherogenic cerebrovascular and cardiovascular large-vessel disease, when compared with their asplenic haematological normal counterparts [Schilling RF. Spherocytosis, splenectomy, strokes and heart attacks. Lancet 1997;350:1677-8; Robinnette CD, Fraumeni Jr JF. Splenectomy and subsequent mortality in veterans of the 1939-1945 war. Lancet 1977;ii:127-9].

Atherosclerosis↗
PubMed2004

Expression of Toll-like receptors 2 and 4 on human intestinal lymphatic vessels.

The Toll-like receptor (TLR) is a part of the innate immune system sensing pathogen-associated molecular patterns (PAMPs). Recently, TLRs 2 and 4 have been demonstrated for the ligand engagements, which result in the induction of cytokines. Here we investigated the expression of TLRs 2 and 4 on lymphatic vessels producing cys-cys chemokine ligand 21 (CCL21) in the human small intestine. The specificity of antibodies to TLRs was tested on a human monocyte leukemia cell line, umbilical vein endothelial cells (HUVEC), and periodontal ligament fibroblasts (PDLF) with the examination for the TLR gene expression by the reverse transcription-polymerase chain reaction (RT-PCR), and lymphatic vessels were identified by antibodies for platelet-endothelial cell adhesion molecule-1 (PECAM-1) and desmoplakin. The expression of CCL21 was not clearly detected on collecting lymphatic vessels in the submucosa while it was generally observed on the central lacteals of villi and lymphatic capillaries in the lamina propria mucosae. The reaction of antibodies to TLRs 2 and 4 was also not clearly detected on collecting lymphatic vessels in the submucosa and central lacteals of villi, but generally observed on lymphatic capillaries expressing CCL21 in the lamina propria mucosae of tissue where the expression of CCL21 and TLRs was not clearly observed in blood vessels. These may suggest that the expression of CCL21, and TLRs 2 and 4 is predominantly induced in the peripheral lymphatic endothelium of the small intestinal microcirculation. The lymphatic endothelium may contribute to allow dendritic cells to home into secondary lymphoid tissue through the expression of TLRs, the ligand engagements of which result in the induction of chemokines.

Aged↗
PubMed2005

Lymphatic vessel density in vocal cord carcinomas assessed with LYVE-1 receptor expression.

BACKGROUND AND PURPOSE: Early stage vocal cord carcinomas are usually cured by radiation therapy despite the use of portals that exclude the cervical lymph nodes. We investigated whether the lymphatic vessel density (LVD) of vocal cord carcinomas differs from that of other head and neck carcinomas. PATIENTS AND METHODS: Deparaffinized tissue from tumors of 60 patients diagnosed with head and neck squamous cell carcinoma (HNSCC) were immunostained for LYVE-1, a novel lymphatic vessel marker. Twenty-two had vocal cord carcinoma. Tumor blood vessel density (BVD) was assessed using immunostaining for CD31. RESULTS: Tumor overall LVD, including both intra- and peritumoral lymph vessels, was 10-fold lower than the BVD (5 counts/mm2 vs. 52 mm(-2), respectively). A high LVD was associated with a high BVD (P = .002), but neither was associated with the tumor size. Both tumor LVD and BVD were lower in vocal cord carcinomas than in HNSCCs arising at other sites (median, 0 vs. 7 mm(-2), P=.016; and median, 36 vs. 52 mm(-2), P = .006, respectively). Only one vocal cord carcinoma was associated with a regional metastasis at the time of the diagnosis. Among the rest of the cases tumor size was a better predictor for the presence of regional metastases than tumor BVD or LVD in a logistic regression model (odds ratio 2.2, 95% CI 1.1-4.5). CONCLUSION: Vocal cord carcinomas have a low lymph vessel density as compared with HNSCCs arising at other sites.

Adult↗