Current intraoperative storage and handling practices of autologous bypass conduit: A survey of the royal australasian college of surgeons

During bypass surgery for peripheral arterial occlusive disease and ischaemic heart disease, autologous graft conduit including great saphenous veins and radial arteries are frequently stored in solution. Endothelial damage adversely affects the performance and patency of autologous bypass grafts, and intraoperative graft storage solutions have been shown to influence this process. The distribution of storage solutions currently used amongst Cardiothoracic and Vascular Surgeons from Australia and New Zealand is not well defined in the literature. The aim of this study was to determine current practices regarding autologous graft storage and handling amongst this cohort of surgeons, and discuss their potential relevance in the context of early graft failure. From this survey, the most frequently used storage solutions were heparinized saline for great saphenous veins, and pH-buffered solutions for radial arteries. Duration of storage was 30–45 min for almost half of respondents, although responses to this question were limited. Further research is required to investigate whether ischaemic endothelial injury generates a prothrombotic state, whether different storage media can alter this state, and whether this is directly associated with clinical outcomes of interest such as early graft failure.

Brain stem death induces pro-inflammatory cytokine production and cardiac dysfunction in sheep model

Introduction

Organs procured following brain stem death (BSD) are the main source of organ grafts for transplantation. However, BSD is associated with inflammatory responses that may damage the organ and affect both the quantity and quality of organs available for transplant. Therefore, we aimed to investigate plasma and bronchoalveolar lavage (BAL) pro-inflammatory cytokine profiles and cardiovascular physiology in a clinically relevant 6-h ovine model of BSD.

Methods

Twelve healthy female sheep (37–42 Kg) were anaesthetized and mechanically ventilated prior to undergoing BSD induction and then monitored for 6 h. Plasma and BAL endothelin-1 and cytokines (IL-1β, 6, 8 and tumour necrosis factor alpha (TNF-α)) were assessed by ELISA. Differential white blood cell counts were performed. Cardiac function during BSD was also examined using echocardiography, and cardiac biomarkers (A-type natriuretic peptide and troponin I were measured in plasma.

Results

Plasma concentrations big ET-1, IL-6, IL-8, TNF-α and BAL IL-8 were significantly (p < 0.01) increased over baseline at 6 h post-BSD. Increased numbers of neutrophils were observed in the whole blood (3.1 × 10⁹ cells/L [95% confidence interval (CI) 2.06–4.14] vs. 6 × 10⁹ cells/L [95%CI 3.92–7.97]; p < 0.01) and BAL (4.5 × 10⁹ cells/L [95%CI 0.41–9.41] vs. 26 [95%CI 12.29–39.80]; p = 0.03) after 6 h of BSD induction vs baseline. A significant increase in ANP production (20.28 pM [95%CI 16.18–24.37] vs. 78.68 pM [95%CI 53.16–104.21]; p < 0.0001) and cTnI release (0.039 ng/mL vs. 4.26 [95%CI 2.69–5.83] ng/mL; p < 0.0001), associated with a significant reduction in heart contractile function, were observed between baseline and 6 h.

Conclusions

BSD induced systemic pro-inflammatory responses, characterized by increased neutrophil infiltration and cytokine production in the circulation and BAL fluid, and associated with reduced heart contractile function in ovine model of BSD.

Endothelin receptor antagonist improves donor lung function in an ex vivo perfusion system

BACKGROUND

A lung transplant is the last resort treatment for many patients with advanced lung disease. The majority of donated lungs come from donors following brain death (BD). The endothelin axis is upregulated in the blood and lung of the donor after BD resulting in systemic inflammation, lung damage and poor lung graft outcomes in the recipient. Tezosentan (endothelin receptor blocker) improves the pulmonary haemodynamic profile; however, it induces adverse effects on other organs at high doses. Application of ex vivo lung perfusion (EVLP) allows the development of organ-specific hormone resuscitation, to maximise and optimise the donor pool. Therefore, we investigate whether the combination of EVLP and tezosentan administration could improve the quality of donor lungs in a clinically relevant 6-h ovine model of brain stem death (BSD).

METHODS

After 6 h of BSD, lungs obtained from 12 sheep were divided into two groups, control and tezosentan-treated group, and cannulated for EVLP. The lungs were monitored for 6 h and lung perfusate and tissue samples were processed and analysed. Blood gas variables were measured in perfusate samples as well as total proteins and pro-inflammatory biomarkers, IL-6 and IL-8. Lung tissues were collected at the end of EVLP experiments for histology analysis and wet-dry weight ratio (a measure of oedema).

RESULTS

Our results showed a significant improvement in gas exchange [elevated partial pressure of oxygen (P = 0.02) and reduced partial pressure of carbon dioxide (P = 0.03)] in tezosentan-treated lungs compared to controls. However, the lungs hematoxylin-eosin staining histology results showed minimum lung injuries and there was no difference between both control and tezosentan-treated lungs. Similarly, IL-6 and IL-8 levels in lung perfusate showed no difference between control and tezosentan-treated lungs throughout the EVLP. Histological and tissue analysis showed a non-significant reduction in wet/dry weight ratio in tezosentan-treated lung tissues (P = 0.09) when compared to control.

CONCLUSIONS

These data indicate that administration of tezosentan could improve pulmonary gas exchange during EVLP.

In vivo liquid biopsy using Cytophone platform for photoacoustic detection of circulating tumor cells in patients with melanoma

Most cancer deaths arise from metastases as a result of circulating tumor cells (CTCs) spreading from the primary tumor to vital organs. Despite progress in cancer prognosis, the role of CTCs in early disease diagnosis is unclear because of the low sensitivity of CTC assays. We demonstrate the high sensitivity of the Cytophone technology using an in vivo photoacoustic flow cytometry platform with a high pulse rate laser and focused ultrasound transducers for label-free detection of melanin-bearing CTCs in patients with melanoma. The transcutaneous delivery of laser pulses via intact skin to a blood vessel results in the generation of acoustic waves from CTCs, which are amplified by vapor nanobubbles around intrinsic melanin nanoclusters. The time-resolved detection of acoustic waves using fast signal processing algorithms makes photoacoustic data tolerant to skin pigmentation and motion. No CTC-associated signals within established thresholds were identified in 19 healthy volunteers, but 27 of 28 patients with melanoma displayed signals consistent with single, clustered, and likely rolling CTCs. The detection limit ranged down to 1 CTC/liter of blood, which is ~1000 times better than in preexisting assays. The Cytophone could detect individual CTCs at a concentration of ≥1 CTC/ml in 20 s and could also identify clots and CTC-clot emboli. The in vivo results were verified with six ex vivo methods. These data suggest the potential of in vivo blood testing with the Cytophone for early melanoma screening, assessment of disease recurrence, and monitoring of the physical destruction of CTCs through real-time CTC counting.

Noninvasive label-free detection of circulating white and red blood clots in deep vessels with a focused photoacoustic probe

Blood clotting is a serious clinical complication of many medical procedures and disorders including surgery, catheterization, transplantation, extracorporeal circuits, infections, and cancer. This complication leads to high patient morbidity and mortality due to clot-induced pulmonary embolism, stroke, and in some cases heart attack. Despite the clear medical significance, little progress has been made in developing the methods for detection of circulating blood clots (CBCs), also called emboli. We recently demonstrated the application of in vivo photoacoustic (PA) flow cytometry (PAFC) with unfocused ultrasound transducers for detection of CBCs in small vessels in a mouse model. In the current study, we extend applicability of PAFC for detection of CBCs in relatively large (1.5-2 mm) and deep (up to 5-6 mm) blood vessels in rat and rabbit models using a high pulse rate 1064 nm laser and focused ultrasound transducer with a central hole for an optic fiber. Employing phantoms and chemical activation of clotting, we demonstrated PA identification of white, red, and mixed CBCs producing negative, positive, and mixed PA contrast in blood background, respectively. We confirmed that PAFC can detect both red and white CBCs induced by microsurgical procedures, such as a needle or catheter insertion, as well as stroke modeled by injection of artificial clots. Our results show great potential for a PAFC diagnostic platform with a wearable PA fiber probe for diagnosis of thrombosis and embolism in vivo that is impossible with existing techniques.

Estrogen is involved in hemangioma regression associated with mast cells

BACKGROUND

Estrogen plays a role in infantile hemangioma (IH) development, but the underlying mechanism remains unclear. This study aimed to assess estrogen and estrogen receptor (ER) localization and expression levels in IH. In addition, the unexpected relationship between mast cells (MCs) and estrogen in human IH was discussed.

METHODS

IH (n = 29), vascular malformation (VMs, n = 33) and normal skin (n = 15) specimens were assessed. IH was classified into proliferative (n = 9; age, 3.56 ± 1.01 months), early involuting (n = 10; age, 8.90 ± 2.69 months) and late involuting (n = 10; age, 20.10 ± 4.93 months) groups. Estradiol (E2), ER-a, ER-β, and tryptase (MC marker) levels were determined immunohistochemically and/or by double immunofluorescence staining. Quantification and localization of tryptase, ER-a, and E2 were assessed for each specimen.

RESULTS

ER-a, E2, and tryptase were expressed in the cytoplasm and nucleus of MCs in IH. The IH specimens showed significantly more tryptase, ER-a, and E2 positive MCs (30.6 ± 12.7, 9.7 ± 5.6, and 19.8 ± 8.7 cells/high-power field [HPF], respectively) compared with VM specimens (9.0 ± 9.8, 1.5 ± 2.4, and 2.5 ± 4.1 cells/HPF, respectively) and normal skin (6.1 ± 8.5, 0.5 ± 1.2, and 1.9 ± 3.4 cells/HPF, respectively). Proliferating IH displayed fewer E2 positive MCs (14.0 6.3 cells/HPF) compared with early (22.3 ± 10.2 cells/HPF, P = 0.023) and late (22.4 ± 6.8 cells/HPF, P = 0.006) involuting specimens. In addition, proliferating IH showed fewer tryptase positive MCs (24.7 ± 10.8 cells/HPF) compared with early involuting specimens (35.7 ± 15.3 cells/HPF, P = 0.043). All IH specimens were ER-a positive and ER-β negative.

CONCLUSIONS

E2 and ER-a are expressed on MCs and not on IH endothelial cells. Furthermore, activated MCs may be involved in IH regression.

Cancer patient perspectives regarding preparedness for end-of-life care: A qualitative study

PURPOSE

The extent to which patients feel prepared for end-of-life (EOL) may be associated with important clinical outcomes. Despite growing interest in the concept of "preparedness," however, there is insufficient information about what cancer patients actually need to feel prepared. Such information is foundational for patient-centered care, theory-building, and instrument development.

DESIGN

This qualitative study examined patient perspectives regarding preparedness for EOL care.

PARTICIPANTS AND METHODS

In-depth interviews were conducted with patients with advanced malignancies and limited life expectancies. Participants were drawn from a large academic cancer center and had a diverse range of malignancies. Thematic text analysis was used to analyze the data.

FINDINGS

Six overarching themes emerged. These included readiness to manage concerns about: (1) EOL planning (e.g., goals of care, location of care); (2) interactions with healthcare providers (e.g., communication, symptom control); (3) interactions with family/friends (e.g., perceived burden, support); (4) emotional well-being (e.g., existential distress, fulfillment); (5) spiritual well-being (e.g., spiritual comfort, congregational support); and (6) financial well-being (e.g., medical expenses, estate planning).

CONCLUSIONS

Findings highlight areas that patients themselves regard as critical for a sense of preparedness for EOL care. Participants emphasized broader concerns than those previously construed as facets of patient preparedness, and these domains offer modifiable targets for intervention.

Effects of supramaximal balloon dilatation pressures on adult cricoid and tracheal cartilage: A cadaveric study

OBJECTIVES/HYPOTHESIS

Cricoid fracture is a serious concern for balloon dilatation in airway stenosis. Furthermore, there are no studies examining tracheal rupture in balloon dilatation of stenotic segments. The aim of this study was to evaluate the effect of supramaximal pressures of balloons on the cricoid and tracheal rings.

STUDY DESIGN

Prospective cadaveric study.

METHODS

Seven cadaveric laryngotracheal complexes of normal adults with intact cricothyroid membranes were acquired. Noncompliant vascular angioplasty balloons (BARD-VIDA) were used for dilatation. The subglottis and trachea were subjected to supramaximal dilatation pressures graduated to nominal burst pressure (NBP) and, if necessary, rated burst pressure (RBP). Larger-diameter balloons, starting from 18 mm size to 24 mm, were used. Dilatations were maintained for 3 minutes.

RESULTS

The cricoid ring was disrupted by larger-diameter balloons (22 mm and 24 mm) even at lower pressures (less than NBP) in six cases. Tracheal cartilages were very distensible, and external examination after supramaximal dilatation (24 mm close to RBP) revealed no obvious cartilage fractures or trachealis tears. Histopathological examination revealed sloughing of mucosa in the areas corresponding to balloon placement, but no microfractures or disruption of the perichondrium of tracheal ring cartilages.

CONCLUSIONS

These results indicate that the cricoid is vulnerable to injury from larger balloons even at lower dilatation pressures. The tracheal cartilages and the membranous wall of the trachea remained resilient to supramaximal dilatation and larger balloons.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:1304-1309, 2018.

Acquired von Willebrand syndrome in respiratory extracorporeal life support: a systematic review of the literature

BACKGROUND AND OBJECTIVE

Venovenous extracorporeal membrane oxygenation (VV ECMO) and extracorporeal CO2 removal (ECCO2R) are increasingly used in the management of severe respiratory failure. With bleeding complications being one of the major risks of these techniques, our aim in this systematic review was to assess the available literature on acquired von Willebrand syndrome (AvWS) and extracorporeal support. AvWS has previously been associated with bleeding and shear stress.

DESIGN AND DATA SOURCES

A systematic review, using Medline via PubMed, was performed to identify eligible studies up to January 2017.

RESULTS AND CONCLUSION

The prevalence of AvWF among patients on VV ECMO or ECCO2R is high, but only a limited number of studies are reported in the literature. AvWS testing should be performed, including vWF multimer analysis, vWF activity and vWF antigen concentration. The extent to which vWF contributes to bleeding during ECMO, or how much changes in ECMO management can influence high molecular weight vWF multimer levels, cannot be answered from the currently available evidence and there remains a need for future studies.

Evaluation of the inferior and superior laryngeal nerve stumps for perineural spread in laryngeal cancer

Objective

Perineural spread (PNS) is an important risk factor for locoregional failure and is correlated with reduced survival rates in squamous cell carcinoma of the larynx. PNS may extend proximally and/or distally in the nerve sheath by leaving unin-volved nerve segments. This method of extension may preclude obtaining tumor-free surgical margins, which may be responsible for recurrent disease. The purpose of this study is to investigate the presence or absence of PNS in extralaryngeal superior and inferior laryngeal nerves in patients who underwent total laryngectomy for squamous cell carcinoma of the larynx.

METHODS

Extralaryngeal segments of superior and inferior laryngeal nerves were resected bilaterally during 15 consecutive laryngectomies. Laryngectomy specimens and the harvested proximal nerve segments were histopathologically examined for the presence or absence of PNS.

RESULTS

Ten of 15 laryngectomy specimens showed PNS; however, none of the extralaryngeal superior or inferior laryngeal nerve segments revealed perineural involvement.

CONCLUSION

Extralaryngeal extension of PNS is highly unlikely in squamous cell carcinoma of the larynx.

Considerations in incorporating office-based ultrasound of the head and neck

OBJECTIVE: The purpose of this study was to determine the cost considerations and strategies for incorporating ultrasound (US) in a head and neck practice.

STUDY DESIGN AND SETTING: A retrospective chart review of office-based US procedures from 2001 to 2005 was completed at our academic medical center. Billing and coding for US and US guided fine needle aspiration (USFNA) were examined.

RESULTS: The appropriate CPT codes are 76536 for US and 76942 and 10022 for USFNA-related procedures. The USFNA codes should be used repeatedly for correct coding of biopsies from multiple sites. Cost (equipment) sharing between specialties is a potential strategy for office-based US incorporation.

CONCLUSION: Based on practice volume, specific CPT coding, and Medicare reimbursements, office-based US equipment and certification costs could be offset in 1 year.

SIGNIFICANCE: Office-based US can be readily incorporated with significant benefits to patients. Billing and usage strategies were identified that would improve the economics of providing office-based US.

In Vivo Long-Term Monitoring of Circulating Tumor Cells Fluctuation during Medical Interventions

The goal of this research was to study the long-term impact of medical interventions on circulating tumor cell (CTC) dynamics. We have explored whether tumor compression, punch biopsy or tumor resection cause dissemination of CTCs into peripheral blood circulation using in vivo fluorescent flow cytometry and breast cancer-bearing mouse model inoculated with MDA-MB-231-Luc2-GFP cells in the mammary gland. Two weeks after tumor inoculation, three groups of mice were the subject of the following interventions: (1) tumor compression for 15 minutes using 400 g weight to approximate the pressure during mammography; (2) punch biopsy; or (3) surgery. The CTC dynamics were determined before, during and six weeks after these interventions. An additional group of tumor-bearing mice was used as control and did not receive an intervention. The CTC dynamics in all mice were monitored weekly for eight weeks after tumor inoculation. We determined that tumor compression did not significantly affect CTC dynamics, either during the procedure itself (P = 0.28), or during the 6-week follow-up. In the punch biopsy group, we observed a significant increase in CTC immediately after the biopsy (P = 0.02), and the rate stayed elevated up to six weeks after the procedure in comparison to the tumor control group. The CTCs in the group of mice that received a tumor resection disappeared immediately after the surgery (P = 0.03). However, CTC recurrence in small numbers was detected during six weeks after the surgery. In the future, to prevent these side effects of medical interventions, the defined dynamics of intervention-induced CTCs may be used as a basis for initiation of aggressive anti-CTC therapy at time-points of increasing CTC number.

Comorbidities and factors associated with endoscopic surgical outcomes in adult laryngotracheal stenosis

This study which is a retrospective chart review aims to characterize the comorbidities associated with adult laryngotracheal stenosis and evaluate the relationship of these with stenosis grade, length, surgical interventions, and surgical intervals. Patients' demographics, medical and surgical comorbidities, grade of stenosis, quantity and degree of balloon dilations, dilation intervals, open airway procedures, and tracheotomy status were recorded from 2002 to 2012, at a tertiary voice and airway center. Surgical outcomes were evaluated in relation to patient comorbidities, stenosis quality, and surgical procedures. A total of 101 patients with laryngotracheal stenosis were examined with female patients comprising 71 % of the population. Seventeen patients (16.8 %) had idiopathic stenosis. Number of balloon dilations ranged from 0 to 24 (mean = 3.3). The average time between dilations was 38.4 weeks (range = 1.14-215.8 weeks). The patients with idiopathic stenosis were found to have a lower grade (p = 0.0066). Fifty-two patients (51.5 %) received a tracheotomy at one point during their management. The 14 patients (13.9 %) who remained tracheotomy dependent had a body mass index (BMI) of >30. No statistically significant correlation was found when the patients' age, BMI and comorbidites were compared with the grade of stenosis, number of balloon dilatations needed and other surgical interventions. On the other hand, interval in between surgeries was found to be longer in patients without an intubation history, and in idiopathic SGS (p = 0.004, p = 0.015, respectively). There was no significant relationship between surgical interval and gender, BMI, length of stenosis, grade (p = 0.059, p = 0.47, p = 0.97, p = 0.36, respectively). Airway stenosis in adults is complicated by the presence of multiple comorbidities. Better understanding of the etiology could aid in the prevention of the injury before it forms.

Disruption of BRD4 at H3K27Ac-enriched enhancer region correlates with decreased c-Myc expression in Merkel cell carcinoma

Pathologic c-Myc expression is frequently detected in human cancers, including Merkel cell carcinoma (MCC), an aggressive skin cancer with no cure for metastatic disease. Bromodomain protein 4 (BRD4) regulates gene transcription by binding to acetylated histone H3 lysine 27 (H3K27Ac) on the chromatin. Super-enhancers of transcription are identified by enrichment of H3K27Ac. BET inhibitor JQ1 disrupts BRD4 association with super-enhancers, downregulates proto-oncogenes, such as c-Myc, and displays antitumor activity in preclinical animal models of human cancers. Here we show that an enhancer proximal to the c-Myc promoter is enriched in H3K27Ac and associated with high occupancy of BRD4, and coincides with a putative c-Myc super-enhancer in MCC cells. This observation is mirrored in tumors from MCC patients. Importantly, depleted BRD4 occupancy at the putative c-Myc super-enhancer region by JQ1 correlates with decreased c-Myc expression. Thus, our study provides initial evidence that super-enhancers regulate c-Myc expression in MCC.

Biased signalling and proteinase-activated receptors (PARs): targeting inflammatory disease

Although it has been known since the 1960s that trypsin and chymotrypsin can mimic hormone action in tissues, it took until the 1990s to discover that serine proteinases can regulate cells by cleaving and activating a unique four-member family of GPCRs known as proteinase-activated receptors (PARs). PAR activation involves the proteolytic exposure of its N-terminal receptor sequence that folds back to function as a 'tethered' receptor-activating ligand (TL). A key N-terminal arginine in each of PARs 1 to 4 has been singled out as a target for cleavage by thrombin (PARs 1, 3 and 4), trypsin (PARs 2 and 4) or other proteases to unmask the TL that activates signalling via Gq , Gi or G12 /13 . Similarly, synthetic receptor-activating peptides, corresponding to the exposed 'TL sequences' (e.g. SFLLRN-, for PAR1 or SLIGRL- for PAR2) can, like proteinase activation, also drive signalling via Gq , Gi and G12 /13 , without requiring receptor cleavage. Recent data show, however, that distinct proteinase-revealed 'non-canonical' PAR tethered-ligand sequences and PAR-activating agonist and antagonist peptide analogues can induce 'biased' PAR signalling, for example, via G12 /13 -MAPKinase instead of Gq -calcium. This overview summarizes implications of this 'biased' signalling by PAR agonists and antagonists for the recognized roles the PARs play in inflammatory settings.

BET protein inhibitor JQ1 attenuates Myc-amplified MCC tumor growth in vivo

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine tumor of the skin currently with no cure. In this study, we have first demonstrated that c-Myc overexpression is common in MCC. By targeting c-Myc, bromodomain inhibitors have demonstrated antitumor efficacy in several preclinical human cancer models. Thus, we interrogated the role of c-Myc inhibition in MCC with c-Myc amplification by using the BET inhibitor JQ1. We have uncovered that c-Myc can be regulated by JQ1 in MCC cells with pathologic c-Myc activation. Moreover, JQ1 potently abrogates c-Myc expression in MCC cells and causes marked G1 cell-cycle arrest. Mechanistically, JQ1-induced cell-cycle arrest coincides with downregulation of cyclin D1 and upregulation of p21, p27, and p57, whereas JQ1 exerts no effect on apoptosis in MCC cells. Further knockdown of p21, p27, or p57 by shRNA partially protects cells from JQ1-induced cell-cycle arrest. In addition, c-Myc knockdown by shRNA generates significant cell-cycle arrest, suggesting that c-Myc overexpression plays a role in MCC pathogenesis. Most importantly, JQ1 significantly attenuates tumor growth in xenograft MCC mouse models. Our results provide initial evidence, indicating the potential clinical utility of BET protein inhibitors in the treatment of MCC with pathologic activation of c-Myc.

Matrix Metalloproteinases and VEGF: Potential Roles in Formation of High-Flow Vascular Anomalies

Objectives:

Arteriovenous malformations (AVMs) are congenital vascular malformations that result from a defect in vascular morphogenesis. These lesions are slow-growing, infiltrative, and destructive resulting in significant morbidity associated with cardiac overload and increased susceptibility to massive bleeding. Recent evidence suggests a role of matrix metalloproteinases (MMPs), a family of enzymes functioning in tissue remodeling via degradation of extracellular matrix proteins and cleaving of surface molecules, in the pathogenesis of AVM development and rupture. This study sought to explore the role of MMPs, particularly MMP-9, in AVM formation and progression.

Methods:

Serum samples from patients with AVM, hemangioma, and pyogenic granuloma were collected and isolated at various stages of development. Relative quantities of MMP-2, MMP-9, and VEGF in each group were calculated and analyzed using sandwich-capture enzyme-linked immunosorbent assay.

Results:

MMP-2 concentrations were found to be decreased in AVM serum samples when compared with serum samples from the pyogenic granuloma controls (27.9 ± 5.97 vs 32.84 ± 2.20, P = 6.3 × 10–9); MMP-9 concentrations were found to be increased in AVM serum samples when compared with hemangioma serum samples (1698.81 ± 410.86 vs 1105.02 ± 239.43, P < .02); and VEGF concentrations were found to be decreased in AVM serum samples when compared with hemangioma serum samples (52.27 ± 63.02 vs 174.0 ± 9.84, P < .05).

Conclusions:

The results of this study provide support for a role of MMP-9 in AVM progression and recurrence. Specifically, an increase in MMP-9 appears to be associated with AVM formation and may play an important role in its pathogenesis.

Pathway-selective antagonism of proteinase activated receptor 2

BACKGROUND AND PURPOSE

Proteinase activated receptor 2 (PAR2) is a GPCR associated with inflammation, metabolism and disease. Clues to understanding how to block PAR2 signalling associated with disease without inhibiting PAR2 activation in normal physiology could be provided by studies of biased signalling.

EXPERIMENTAL APPROACH

PAR2 ligand GB88 was profiled for PAR2 agonist and antagonist properties by several functional assays associated with intracellular G-protein-coupled signalling in vitro in three cell types and with PAR2-induced rat paw oedema in vivo.

KEY RESULTS

In HT29 cells, GB88 was a PAR2 antagonist in terms of Ca(2+) mobilization and PKC phosphorylation, but a PAR2 agonist in attenuating forskolin-induced cAMP accumulation, increasing ERK1/2 phosphorylation, RhoA activation, myosin phosphatase phosphorylation and actin filament rearrangement. In CHO-hPAR2 cells, GB88 inhibited Ca(2+) release, but activated G(i/o) and increased ERK1/2 phosphorylation. In human kidney tubule cells, GB88 inhibited cytokine secretion (IL6, IL8, GM-CSF, TNF-α) mediated by PAR2. A rat paw oedema induced by PAR2 agonists was also inhibited by orally administered GB88 and compared with effects of locally administered inhibitors of G-protein coupled pathways.

CONCLUSIONS AND IMPLICATIONS

GB88 is a biased antagonist of PAR2 that selectively inhibits PAR2/G(q/11)/Ca(2+)/PKC signalling, leading to anti-inflammatory activity in vivo, while being an agonist in activating three other PAR2-activated pathways (cAMP, ERK, Rho) in human cells. These findings highlight opportunities to design drugs to block specific PAR2-linked signalling pathways in disease, without blocking beneficial PAR2 signalling in normal physiology, and to dissect PAR2-associated mechanisms of disease in vivo.

A xenograft animal model of human arteriovenous malformations

Background

Arteriovenous malformations (AVMs) are a type of high-flow vascular malformations that most commonly occurs in the head and neck. They are present at birth but are usually clinically asymptomatic until later in life. The pathogenesis of AVMs remains unclear and therapeutic approaches to AVMs are unsatisfied. In order to provide a tool for studying the pathogenesis and therapies of this disease, we established and studied a xenograft animal model of human AVMs.

Methods

Fresh human AVMs specimens harvested from 4 patients were sectioned (5x5x5 mm) and xenografted subcutaneously in 5 immunologically naïve nude mice (Athymic Nude-Foxn1^nu). Each mouse had four pieces specimens in four quadrants along the back. The grafts were observed weekly for volume, color and texture. The grafts were harvested at every 30 days intervals for histologic examination. All grafts (n = 20) were sectioned and stained for hematoxylin and eosin (H&E). Comparative pathologic evaluation of the grafts and native AVMs were performed by two blinded pathologists. Immunohistochemical examination of human-specific nuclear antigen, vascular endothelial growth factor receptor-2 (VEGFR-2) and Ki-67 was performed.

Results

Clinical characteristics and pathologic diagnosis of native human derived AVMs were confirmed. 85% (n = 17) of AVM xenografts survived although the sizes decreased after implantation. Histological examination demonstrated numerous small and medium-size vessels and revealed structural characteristics matching the native AVMs tissue.76.5% (n = 13) of the surviving xenografts were positive for Ki-67 and human-specific nuclear antigen suggesting survival of the human derived tissue, 52.9% (n = 9) were positive for VEGFR-2.

Conclusions

This preliminary xenograft animal model suggests that AVMs can survive in the nude mouse. The presence of human-specific nuclear antigen, VEGFR-2, and Ki-67 demonstrates the stability of native tissue qualities within the xenografts.

Venous Anastomosis with Microvascular Coupler in Head and Neck Reconstruction: Experience in 200 Consecutive Procedures

Objectives:

There is a scarcity of data on outcomes when GEM microvascular coupler is used for head and neck reconstruction. We sought to review our experience in a large, contemporary series.

Methods:

Retrospective chart review of 201 consecutive flaps performed in 193 patients between September 2009 and January 2013 in a tertiary academic setting.

Results:

The cohort consisted of 125 males with a mean age of 64 years (range 3-83). A double free flap was performed in 8 cases. The most common defect locations were mandible (n = 62, 30.8%); oral cavity (n = 27, 13.4%), and cutaneous (n = 24, 11.9%). Flaps included anterolateral thigh (n = 85, 42.3%); fibula (n = 53, 26.4%); radial forearm (n = 37,18.4%); scapula, latissimus, and rectus (n=5, 2.5% respectively); iliac crest and vastus (n = 4, 2% respectively); and other (n = 3, 1.5%). A double venous anastomosis was performed in 26 flaps. The entire range of couplers (1-4mm) was used, but the 2.5mm was the most commonly used (n = 83, 36.6%) followed by the 2.0mm (n = 47, 20.7%). Facial (n = 134, 59%), External jugular (n = 32, 14.1%), and superficial temporal (n = 22; 9.7%) were the most common recipient vessels. Seven cases underwent microvascular revision yielding arterial thrombosis in 1 case, pedicle torsion in 1 case, and venous thrombosis in 5 cases. The flap was successfully salvaged in 3 cases. A delayed failure in another patient yielded an overall flap success rate of 97.5%. None of the tested variables reached statistical significance for venous thrombosis or flap survival.

Conclusions:

The microvascular coupler is a reliable alternative for venous anastomosis in head and neck flaps. Given the low failure rate, a multi-institutional study could help elucidate outcome predictors in this setting.

Guidelines for the treatment of head and neck venous malformations

Venous malformation is one of the most common benign vascular lesions, with approximately 40% of cases appearing in the head and neck. They can affect a patient's appearance and functionality and even cause life-threatening bleeding or respiratory tract obstruction. The current methods of treatment include surgery, laser therapy, sclerotherapy, or a combined. The treatment of small and superficial venous malformations is relatively simple and effective; however, the treatment of deep and extensive lesions involving multiple anatomical sites remains a challenge for the physicians. For complex cases, the outcomes achieved with one single treatment approach are poor; therefore, individualized treatment modalities must be formulated based on the patient's condition and the techniques available. Comprehensive multidisciplinary treatments have been adapted to achieve the most effective results. In this paper, based on the national and international literature, we formulated the treatment guidelines for head and neck venous malformations to standardize clinical practice. The guideline will be renewed and updated in a timely manner to reflect cutting-edge knowledge and to provide the best treatment modalities for patients.

Modulating human proteinase activated receptor 2 with a novel antagonist (GB88) and agonist (GB110)

BACKGROUND AND PURPOSE

Many cells express proteinase activated receptor 2 (PAR2) on their plasma membrane. PAR2 is activated by proteolytic enzymes, such as trypsin and tryptase that cleave the receptor N-terminus, inititating signalling to intracellular G proteins. Studies on PAR2 have relied heavily upon activating effects of proteases and peptide agonists that lack stability and bioavailability in vivo.

EXPERIMENTAL APPROACH

A novel small molecule agonist GB110 and an antagonist GB88 were characterized in vitro against trypsin, peptide agonists, PAR2 antibody, PAR1 agonists and flow cytometry,in seven cell lines using intracellular Ca(2+) mobilization and examined in vivo against PAR2- and PAR1-induced rat paw oedema.

KEY RESULTS

GB110 is a potent non-peptidic agonist activating PAR2-mediated Ca(2+) release in HT29 cells (EC(50) ∼200 nM) and six other human cell lines, inducing PAR2 internalization. GB88 is a unique PAR2 antagonist, inhibiting PAR2 activated Ca(2+) release (IC(50) ∼2 µM) induced by native (trypsin) or synthetic peptide and non-peptide agonists. GB88 was a competitive and surmountable antagonist of agonist 2f-LIGRLO-NH(2), a competitive but insurmountable antagonist of agonist GB110, and a non-competitive insurmountable antagonist of trypsin. GB88 was orally active and anti-inflammatory in vivo, inhibiting acute rat paw oedema elicited by agonist GB110 and proteolytic or peptide agonists of PAR2 but not by corresponding agonists of PAR1 or PAR4.

CONCLUSIONS AND IMPLICATIONS

The novel PAR2 agonist and antagonist modulate intracellular Ca(2+) and rat paw oedema, providing novel molecular tools for examining PAR2-mediated diseases.

Video-Assisted ALT Harvesting, Technique Validation, and Results

Objective: We have previously described a novel video-assisted technique (VAT) for the identification of cutaneous perforators of the anterolateral thigh (ALT) free flap. We sought to validate the technique by comparing its findings with standard open thigh exploration in a series of consecutive patients.

Method: Retrospective review of a prospectively collected database; 23 consecutive cases operated at a tertiary academic institution between September 2010 and October 2011. In all these cases a standard open exploration of the thigh—considered the gold standard—was performed immediately after the endoscopic exploration. Data retrieved included surgical findings, demographics, and outcomes.

Results: There were 16 males and 7 females with a mean age of 55 (23-83). The most common defect location was cutaneous n = 7 (30.4%) and oral cavity in n = 6 (26.1%). Average operative time for VAT was 25.4 minutes (9-47). On standard exploration there were 53 total perforators identified; 49 of these were successfully identified endoscopically. Findings were discordant in 4 cases (17.4%), with the endoscopic technique missing 1 perforator in all of 4 of them. The sensitivity of VAT was 92.4% (CI, 80.9-97.5) with a correlation coefficient of 0.91 with open exploration. All flaps survived, and there were no complications associated with the technique.

Conclusion: Video-assisted exploration has a high sensitivity for identification of cutaneous perforators of the thigh. There is a high correlation between findings with this technique and a standard open approach. This minimally invasive technique could help minimize donor site morbidity in patients undergoing reconstruction with an ALT free flap.

A Survival Analysis for Primary and Salvage Ablative Surgery with Microvascular Reconstruction for Squamous Cell Carcinoma of the Upper Aerodigestive Tract

Objective: Provide prognostic data for the physicians and patients when a decision is made for primary or salvage ablative surgery of the upper aerodigestive tract with the aide of microvascular reconstruction.

Method: Retrospective chart review of patients with primary or recurrent upper aerodigestive tract squamous cell carcinoma treated with free flap reconstruction between 1993 and 2009. Prior treatment, recurrence time and site, sex, age, complications, cause of death, stage, and survival rates were analyzed.

Results: A total of 219 patients were identified. Mean age was 59.6 years. A total of 136 patients underwent primary resection with immediate reconstruction, 83 patients underwent salvage treatment. A total of 196 patients had advanced clinical stage oral (n = 129) and oropharyngeal squamous cell carcinomas (n = 51). Median overall survival for all patients was 21.7 months (CI 16.2, 33.1) with median recurrence free survival of 12.6 months (CI 8.8, 16.6). Median overall survival was 31.3 months (CI 18.6, 48.6) for primary resection group and 14.6 months for salvage group (CI 11.4, 21.5). Recurrence free median survival was 16.6 months for the primary resection group and 7.7 months for salvage group ( P = .009).

Conclusion: The surgeon and the patient need to be aware of survival rates, when radical resection with free flap reconstruction offered; especially in salvage setting. This may help the patient and the surgeon in choosing the most suitable treatment modality for any given condition.

Decision Making in Post-chemoradiotherapy Neck Dissections

Objective: There is continued debate as to whether to perform a neck dissection as a planned vs “wait and see” procedure in patients with head and neck cancer treated with chemoradiotherapy. In this study we aimed to review our results to help with the decision making process.

Method: A retrospective review of 140 oropharyngeal cancer cases treated with chemoradiotherapy was performed. Demographic data and treatment outcomes were extracted. The patients who underwent neck dissections were selected and evaluated as to how the decision was made; this included clinical examination, imaging studies, and fine needle aspiration biopsy.

Results: Of the 140 patients, 19 underwent ND for persistent disease. This included 9 patients with tonsil and 10 with base of tongue cancer. The decision for a ND was made according to CT scan findings in 7 patients, FNAB in 2 patients, PET imaging in 3 patients, clinical examination in 4 patients, and the combination of imaging and clinical findings in three patients. The dissections were performed at an average of 10 weeks (range, 4-20 weeks). Seven patients (37%) had no viable cancer in the ND specimen. The pre-treatment neck staging showed no significant difference.

Conclusion: Head and neck surgeons are in search of reliable methods to determine patients at risk of persistent disease. In this series, 37% of the patients had no viable tumor in the ND specimen. Further studies are needed to identify patients who are not in need of a ND.

The Method of Establishing a Xenograft Animal Model

Objective: 1) Establish a xenograft animal model of arteriovenous malformation (AVM), an uncommon and often incurable vascular anomaly. 2) Observe the morphological alterations and histological characteristics of xenograft AVM.

Method: AVM specimens harvested from 4 patients were sectioned (5x5x5mm) and implanted in the subcutaneous dorsum of 5-Athymic Nude-Foxn1nu mice. 4 implants per animal were placed (N = 20). Specimens were harvested monthly and stained for hematoxylin and eosin (H&E). Immunohistochemistry for anti-human nuclear antigen and Ki-67 was performed. Histologic observations were recorded by 2-blinded pathologists.

Results: Clinical characteristics and pathologic diagnosis of AVM was confirmed in each donor patient. A total of 85% (n = 17) of AVM xenografts survived the xenograft implantation. Survival was unrelated to date of harvest. The majority of implants slightly decreased in size by date of harvest (1-2mm). Pathologic diagnosis of a vascular anomaly was confirmed in each implant and demonstrated numerous small and medium-size vessels. A total of 76.5% (n = 13) of implants of surviving xenografts were positive for Ki-67 and anti-human nuclear antigen, confirming survival of the human derived tissue.

Conclusion: We herein describe an animal model for AVM that may provide the first step for examining the pathophysiology and potential treatment of these difficult to treat lesions in vivo.

Distinct epigenetic profiling in head and neck squamous cell carcinoma stem cells

OBJECTIVE

To identify unique epigenetic signature in cancer stem cells (CSCs) in head and neck squamous cell carcinoma (HNSCC).

STUDY DESIGN

Molecular and microarray studies.

SETTING

Tertiary referral center.

SUBJECTS AND METHODS

Head and neck CSCs were isolated in HNSCC cells by CD44 staining and flow cytometry sorting. CSCs with highest CD44 expression (CD44(hi)) and non-stem cells (non-SCs) with lowest CD44 expression (CD44(low)) were then characterized for stemness gene expression and their responses to chemotherapeutic agents, followed by high-throughput epigenetic profiling using the Illumina BeadChip Array, targeting 28,544 CpG sites covering more than 14,956 genes.

RESULTS

CD44(hi) CSCs expressed higher levels of stem cell markers and were more resistant to chemotherapeutic agents as compared to CD44(low) non-SCs. By DNA methylation microarray analysis, 17 hypomethylated and 9 hypermethylated genes were identified in CD44(hi) CSCs as compared to non-SCs in most HNSCC cell lines. Cluster analysis using these 26 genes showed that CD44(hi) CSCs were epigenetically distinct from the CD44(low) non-SCs in all 5 HNSCC cell lines.

CONCLUSION

A unique epigenetic profile consisting of 17 hypomethylated and 9 hypermethylated genes was seen in HNSCC CSCs. These genes may be critically required in maintaining the stemness or pluripotency of CSCs and may represent novel molecular targets for anticancer therapies aimed at eradicating CSCs in HNSCC.

Treatment guideline for hemangiomas and vascular malformations of the head and neck

Vascular anomalies are among the most common congenital and neonatal dysmorphogenesis, which are separated into hemangiomas and vascular malformations. They can occur in various areas throughout the body, with 60% being located in the head and neck. The true mechanism of pathogenesis of vascular anomalies is still unclear. Various treatment methods have been reported, and there are still controversies over the selection of different treatment modalities. Based on the clinical and basic research and current literature, the Chinese Division of Oral and Maxillofacial Vascular Anomalies formulated a treatment guideline for hemangiomas and vascular malformations of the head and neck, which will be modified and updated periodically based on new medical evidence and research.

Endoscopic management of airway venous malformations with Nd:YAG laser

OBJECTIVES

The neodymium:yttrium-aluminum-garnet (Nd:YAG) laser is a powerful tool in treating venous malformations (VMs) involving the upper airway. If left untreated, laryngeal VMs can lead to life-threatening airway obstruction. We aimed to evaluate the efficacy of endoscopic management of laryngeal VMs with the Nd:YAG laser.

METHODS

We performed a 12-year retrospective review in a tertiary referral center. Patient records were reviewed for demographics, presenting symptoms, area of involvement, age at first Nd:YAG laser therapy, total number of treatments, time between treatments, and treatment response.

RESULTS

Seventeen patients were treated endoscopically with an Nd:YAG laser for laryngeal VMs. The mean age at first treatment was 23.0 years (range, 18 to 45 years). The majority of patients presented with obstructive sleep apnea (58.8%), and 17.5% of patients presented with acute airway obstruction or stridor. The remaining patients presented with minor symptoms, including chronic cough and voice changes. The VMs involved the supraglottis, glottis, or both in 29%, 35%, and 35% of patients, respectively. An average of 4 treatments were required per patient (median, 3.5; range, 1 to 9). The time between treatments increased with each consecutive laser therapy, starting at a mean of 3.8 months between the first and second treatments to 21.7 months between the third and fourth. A marked reduction in VM size and symptom improvement were achieved in each patient after Nd:YAG therapy. Two complications (3%) were encountered among 66 total procedures.

CONCLUSIONS

Endoscopic management of VMs using an Nd:YAG laser appears to be both effective and relatively safe. Multiple treatments are often required, but increased time can elapse between consecutive therapies. Use of the Nd:YAG laser for laryngeal VMs helps avoid tracheotomy and open surgical resection.

Diagnosis and management of pediatric cervicofacial venous malformations: retrospective review from a vascular anomalies center

OBJECTIVES/HYPOTHESIS

Venous malformations are rare congenital aberrations of vein development frequently presenting in the head and neck. Without treatment, venous malformations cause progressive disfigurement, dysfunction, and bleeding. In this study, we analyzed a cohort of pediatric patients with cervicofacial venous malformations (CFVM), with the goal of developing a treatment algorithm for these complex lesions.

STUDY DESIGN

Eleven-year retrospective chart review. The setting was a vascular anomalies center at a pediatric tertiary hospital. Nineteen patients (10 male, 9 female), aged 11 months to 17 years, presented with CFVM.

METHODS

Patient charts were reviewed for demographics, signs and symptoms, timing of first and subsequent interventions, total number and type of interventions performed, and procedural complications. A family questionnaire supplemented outcome measures by determining the perception of disease control.

RESULTS

Presenting symptoms for CFVM include growth (100%), disfigurement (63%), pain (58%), respiratory compromise (42%), and dysphagia (32%). A mean of 6.7 interventions were performed per patient (median, 6; range, 2-12), requiring a mean of 0.8 excisions, 4.6 laser treatments, and 1.3 sclerotherapy injections. Average age at first procedure was 8.5 years. Time between treatments averaged 8.9 months. Four complications occurred in 127 procedures (3.1%). Questionnaire responses indicated subjective improvement following therapy. A management algorithm could be developed from therapeutic outcomes.

CONCLUSIONS

Treatment of CFVM can be safely and successfully performed with a combination of laser therapy, sclerotherapy, and surgical excision. A treatment algorithm involving multiple procedures during childhood can lead to successful management of CFVM.

Clinical course of arteriovenous malformations of the head and neck: A case series

Objective: To demonstrate, in a case series, the relentless growth of arteriovenous malformations (AVMs) of the head and neck and the importance of their vigilant management within the context of a modified staging system.

Study Design: Retrospective review.

Setting: Tertiary care institution, Vascular Anomalies Center.

Subjects and Methods: Subjects were patients with advanced AVMs presenting to our Vascular Anomalies Center. Medical records were examined for age at first diagnosis, disease course, prior treatments, age at presentation, management, therapeutic outcomes, stage of disease, and impact on quality of life. Early patient photographs were evaluated.

Results: Ten patients (ages 13-46 yrs) with extensive cervicofacial AVMs were examined. Progressive growth, worsening symptoms, and graduated disease stage were universally experienced by each patient, as evident by serial photographs, over a course of many years. Each patient presented to our institution with massive lesions, bleeding, pain, and facial destruction. Prior embolization and/or surgery had been performed in all but one patient. Every patient had been previously told that their AVMs were incurable or that treatment options were exhausted. The patients were subsequently treated at our institution with surgical resection with or without preoperative embolization. Disease control, symptom improvement, and enhanced daily functioning were attained in each patient.

Conclusion: The natural course of AVMs is progressive, invasive, and destructive. Vigilant observation, early treatment, and radical therapy are necessary for AVMs of the head and neck.

Increased microsatellite instability and epigenetic inactivation of the hMLH1 gene in head and neck squamous cell carcinoma

OBJECTIVE

The study is designed to elucidate the relationship between epigenetic silencing of the hMLH1 (human MutL homologue 1) gene and microsatellite instability (MSI) and the prognostic values of hMLH1 promoter methylation and MSI in head and neck squamous cell carcinoma (HNSCC).

STUDY DESIGN

Cross-sectional study.

SETTING

Tertiary referral center.

SUBJECTS AND METHODS

A total of 120 cases of HNSCC were analyzed for hMLH1 promoter hypermethylation, protein expression, and MSI by using methylation-specific polymerase chain reaction, immunohistochemical staining, and polymerase chain reaction amplification with the use of 16 fluorescent-labeled microsatellite markers, followed by fragment analysis.

RESULTS

Of 120 HNSCCs, hMLH1 promoter hypermethylation and decreased hMLH1 protein expression were shown in 39 (32.5%) and 22 (18.3%), respectively. hMLH1 promoter hypermethylation was detected in 13 of 52 (25%) normal-appearing squamous mucosa adjacent to invasive carcinoma. MSI was detected in 21 (17.5%) tumors at two or more markers and in 99 (82.5%) tumors with no evidence of MSI or at only one marker. Hypermethylation of the hMLH1 gene is significantly associated with decreased hMLH1 protein expression (P < 0.001). High-frequency MSI was significantly associated with promoter hypermethylation (P = 0.01) but not with decreased protein expression (P = 0.069) of hMLH1 gene. hMLH1 promoter hypermethylation is significantly associated with decreased cause-specific survival for HNSCC patients (P = 0.03).

CONCLUSIONS

Promoter hypermethylation of the hMLH1 gene could be detected early in head and neck squamous carcinogenesis and may be associated with increased MSI and poor survival in HNSCC.

Toward a 1550 nm InGaAs photoconductive switch for terahertz generation

We report a terahertz (THz) photoconductive switch made from a composite of metal ErAs nanoparticles embedded in In(0.53)Ga(0.47)As and coupled to a square spiral antenna. The THz output power was measured in a 77 K cryostat by using a standard hyperhemisphere-lens package, a Golay cell outside the cryostat, and a quasi-optical filter bank for spot frequency spectral measurements. Results indicate an average output power of approximately 12 microW at 22 V bias using 140 mW of optical pump power from a subpicosecond fiber mode-locked laser. In addition, the THz spectra displayed invariance to bias voltage despite operating near impact ionization.

In vivo, noninvasive, label-free detection and eradication of circulating metastatic melanoma cells using two-color photoacoustic flow cytometry with a diode laser

The circulating tumor cell (CTC) count has been shown as a prognostic marker for metastasis development. However, its clinical utility for metastasis prevention remains unclear, because metastases may already be present at the time of initial diagnosis with existing assays. Their sensitivity ex vivo is limited by a small blood sample volume, whereas in vivo examination of larger blood volumes may be clinically restricted by the toxicity of labels used for targeting of CTCs. We introduce a method for in vivo photoacoustic blood cancer testing with a high-pulse-repetition-rate diode laser that, when applied to melanoma, is free of this limitation. It uses the overexpression of melanin clusters as intrinsic, spectrally-specific cancer markers and signal amplifiers, thus providing higher photoacoustic contrast of melanoma cells compared with a blood background. In tumor-bearing mouse models and melanoma-spiked human blood samples, we showed a sensitivity level of 1 CTC/mL with the potential to improve this sensitivity 10(3)-fold in humans in vivo, which is impossible with existing assays. Additional advances of this platform include decreased background signals from blood through changes in its oxygenation, osmolarity, and hematocrit within physiologic norms, assessment of CTCs in deep vessels, in vivo CTC enrichment, and photoacoustic-guided photothermal ablation of CTCs in the bloodstream. These advances make feasible the early diagnosis of melanoma during the initial parallel progression of primary tumor and CTCs, and laser blood purging using noninvasive or hemodialysis-like schematics for the prevention of metastasis.

Progesterone Receptors Identified in Vascular Malformations of the Head and Neck

OBJECTIVE: To identify hormone receptors within vascular malformations (arteriovenous malformations [AVMs], venous malformations [VMs], and lymphatic malformations [LMs]) of the head and neck.

STUDY DESIGN: Immunohistochemical staining for estrogen receptor (ER) and progesterone receptor (PR) was performed on archival vascular malformation tissue collected from both pediatric and adult patients.

SETTING: Tertiary referral center from 2006 to 2008.

SUBJECTS AND METHODS: Twelve AVM, 10 VM, and eight LM specimens were stained for both ER and PR. Ten breast carcinoma specimens were used as controls, with the carcinoma cells serving as positive controls, and the endothelium and smooth muscle cells of the blood vessels serving as negative controls. Five normal supraglottic mucosal samples served as head and neck controls. The Fisher exact test was used for statistical analysis.

RESULTS: Ten of the 12 (83%) AVM specimens stained diffusely positive for PR within the nuclei of the endothelium and smooth muscle of the malformed vessels ( P < 0.0001). Five of the 10 (50%) VM specimens stained positive for PR (2 [20%] focal, 3 [30%] diffuse) within the nuclei of the endothelium and smooth muscle of the malformed vessels ( P = 0.0325). Four of the eight (50%) LM specimens stained focally positive for PR within the nuclei of the endothelium of the malformed vessels ( P = 0.0229). None of the vascular malformation specimens stained positive for ER.

CONCLUSION: Our data suggest that PR, but not ER, is expressed in AVMs, VMs, and LMs of the head and neck.

The expression of vascular endothelial growth factor and its receptors in port-wine stains

OBJECTIVE

To investigate the expression of vascular endothelial growth factor (VEGF) and its receptor (VEGF-R2) in port-wine stains (PWSs).

DESIGN

An immunohistochemistry (IHC) study on formalin-fixed, paraffin-embedded specimens.

METHODS

Representative sections from surgical resection specimens of 12 PWS patients and 12 control specimens stained with routine IHC by using polyclonal anti-VEGF and anti-VEGF-R2 antibodies. Slides were evaluated semiquantitatively for the intensity of staining for VEGF and VEGF-R2 by using a scoring system varying from 0 to 3+.

RESULTS

PWS specimens showed statistically significant overexpression of both VEGF and VEGF-R2 molecules when compared with control specimens (P < 0.005).

CONCLUSIONS

VEGF and its receptor may play an important role in the pathogenesis of PWS. It is possible that PWS may progress by hyperplasia in addition to hypertrophy. VEGF-R blockade may have a potential role as a targeted approach in the treatment of this disfiguring condition in the future.

Natural History of Arteriovenous Malformations

Objective

1) To demonstrate the natural history of arteriovenous malformation (AVMs) when left untreated or inadequately managed. 2) To demonstrate the need for major treatment to patients, families, healthcare providers, and insurance companies.

Methods

Records from 10 of 50 representative patients treated at University of Arkansas for Medical Sciences (UAMS) for advanced AVMs were reviewed for age at presentation, gender, presenting symptoms, previous treatment, disease course, and post-presentation management. Patients were asked if quality of life had improved after treatment at UAMS Facial photos from childhood were obtained and compared with photos taken at time of presentation.

Results

10 patients (7 male, 3 female, range 21–46 years) received treatment. All patients presented with bleeding, pain and/or facial destruction. 6 of 10 patients received previous embolization. No patients had undergone previous surgical resection. All were informed by a previous physician that the disease was incurable or treatment options had been exhausted. All patients experienced subsequent worsening of symptoMS All patients were treated at UAMS with preoperative embolization followed by surgical resection and required multiple surgeries to remove persistent AVM. All patients indicated quality of life improved after embolization/surgical resection. Comparison of photos revealed progression of disease in all cases marked by facial destruction and deformity.

Conclusions

AVMs display a progressive and destructive nature when left untreated or inadequately managed. Natural history can be used to demonstrate to patients, families, and healthcare providers the seriousness of disease and convince insurance companies that radical treatment is typically necessary to obtain control or cure.

Reflective terahertz imaging of porcine skin burns

A reflective pulsed terahertz imaging system based on direct detection was developed and used to obtain high-resolution images of a porcine skin specimen with superficial partial-thickness (second-degree) burns. Images were also obtained of the sample through ten layers of dry medical (cotton) gauze with minimal image degradation. The burned and unburned regions of skin had large differences in terahertz reflectivity, displaying clear delineation [20 dB signal-to-noise ratio (SNR) difference signal] between both regions in the images. The terahertz images also exhibited a "halo" surrounding the burn areas that may correlate to the extent of burn injury. The system operated at a center frequency of 500 GHz with 125 GHz of 3 dB bandwidth and used whiskbroom scanning to generate images with a spatial resolution of 1.5 mm. Each pixel was acquired with a 16 ms integration time, resulting in a 40 dB postdetection SNR. The simplicity and high SNR of the reflective terahertz system are promising steps toward real-time terahertz medical imaging.

Bisphosphonates and jaw osteonecrosis: the UAMS experience

BACKGROUND

Over the past year at least 10 case series and several case reports on osteonecrosis of the jaw (ONJ) have been published with most found in the oral surgery literature. This clinical entity is largely unknown to head and neck surgeons.

METHODS

Retrospective chart review.

RESULTS

A total of 479 charts were reviewed, identifying 25 individuals meeting inclusion criteria. Mean age was 63.4 (standard deviation, 9.9) years; 40% were female. Multiple myeloma was the most common comorbidity. Twenty-five patients were treated with bisphosphonates for 4.4 years (range, 1 to 8 years); most commonly pamidronate before ONJ diagnosis. Forty-two percent (10) took steroids within the month before diagnosis. Fifty-two percent (11) underwent dental work before developing ONJ.

CONCLUSION

These data reflect the importance of awareness of the possibility of ONJ with bisphosphonate therapy.

Use of Recombinant Factor VIIa During Excision of Vascular Anomalies

BACKGROUND

The surgical excision of vascular anomalies is often accompanied with significant perioperative bleeding. Novel hemostatic agents, including recombinant factor VIIa (rVIIa), have been shown to reduce bleeding in hemophilia and trauma patients along with decreasing blood loss during various surgical procedures. The role of rVIIa during excision of vascular anomalies has not been examined.

METHODS

A retrospective chart review of patients from 2001 to 2003 who received perioperative rVIIa during excision of vascular anomalies at one institution.

RESULTS

Nine patients were identified who received perioperative rVIIa during removal of their vascular anomalies (7 venous malformations, 1 lymphatic-venous malformation, 1 arteriovenous malformation). All patients received at least one dose of rVIIa during the perioperative period (2/9 received 2 doses). An accurate account of hourly blood loss was reported, and could be graphed, in three patients. These patients displayed significant reductions in hourly blood loss after the administration of rVIIa. These cases are detailed in this report. Surgeons reported subjective improvements in operative bleeding, efficiency, and operative time in six of six patients after the administration of rVIIa intraoperatively. Reduced postoperative bleeding was reported in two patients who received rVIIa for persistent drain output.

CONCLUSION

rVIIa may be an effective adjunct in improving the surgical efficiency and outcome of excised vascular anomalies.