Translocator protein is a marker of activated microglia in rodent models but not human neurodegenerative diseases

Microglial activation plays central roles in neuroinflammatory and neurodegenerative diseases. Positron emission tomography (PET) targeting 18 kDa Translocator Protein (TSPO) is widely used for localising inflammation in vivo, but its quantitative interpretation remains uncertain. We show that TSPO expression increases in activated microglia in mouse brain disease models but does not change in a non-human primate disease model or in common neurodegenerative and neuroinflammatory human diseases. We describe genetic divergence in the TSPO gene promoter, consistent with the hypothesis that the increase in TSPO expression in activated myeloid cells depends on the transcription factor AP1 and is unique to a subset of rodent species within the Muroidea superfamily. Finally, we identify LCP2 and TFEC as potential markers of microglial activation in humans. These data emphasise that TSPO expression in human myeloid cells is related to different phenomena than in mice, and that TSPO-PET signals in humans reflect the density of inflammatory cells rather than activation state.

Lysosomal acidification dysfunction in microglia: an emerging pathogenic mechanism of neuroinflammation and neurodegeneration

Microglia are the resident innate immune cells in the brain with a major role in orchestrating immune responses. They also provide a frontline of host defense in the central nervous system (CNS) through their active phagocytic capability. Being a professional phagocyte, microglia participate in phagocytic and autophagic clearance of cellular waste and debris as well as toxic protein aggregates, which relies on optimal lysosomal acidification and function. Defective microglial lysosomal acidification leads to impaired phagocytic and autophagic functions which result in the perpetuation of neuroinflammation and progression of neurodegeneration. Reacidification of impaired lysosomes in microglia has been shown to reverse neurodegenerative pathology in Alzheimer's disease. In this review, we summarize key factors and mechanisms contributing to lysosomal acidification impairment and the associated phagocytic and autophagic dysfunction in microglia, and how these defects contribute to neuroinflammation and neurodegeneration. We further discuss techniques to monitor lysosomal pH and therapeutic agents that can reacidify impaired lysosomes in microglia under disease conditions. Finally, we propose future directions to investigate the role of microglial lysosomal acidification in lysosome-mitochondria crosstalk and in neuron-glia interaction for more comprehensive understanding of its broader CNS physiological and pathological implications.

A Pragmatic Randomized Trial Comparing Surgical Clipping and Endovascular Treatment of Unruptured Intracranial Aneurysms

BACKGROUND AND PURPOSE

Surgical clipping and endovascular treatment are commonly used in patients with unruptured intracranial aneurysms. We compared the safety and efficacy of the 2 treatments in a randomized trial.

MATERIALS AND METHODS

Clipping or endovascular treatments were randomly allocated to patients with one or more 3- to 25-mm unruptured intracranial aneurysms judged treatable both ways by participating physicians. The study hypothesized that clipping would decrease the incidence of treatment failure from 13% to 4%, a composite primary outcome defined as failure of aneurysm occlusion, intracranial hemorrhage during follow-up, or residual aneurysms at 1 year, as adjudicated by a core lab. Safety outcomes included new neurologic deficits following treatment, hospitalization of >5 days, and overall morbidity and mortality (mRS > 2) at 1 year. There was no blinding.

RESULTS

Two hundred ninety-one patients were enrolled from 2010 to 2020 in 7 centers. The 1-year primary outcome, ascertainable in 290/291 (99%) patients, was reached in 13/142 (9%; 95% CI, 5%-15%) patients allocated to surgery and in 28/148 (19%; 95% CI, 13%-26%) patients allocated to endovascular treatments (relative risk: 2.07; 95% CI, 1.12-3.83; P = .021). Morbidity and mortality (mRS >2) at 1 year occurred in 3/143 and 3/148 (2%; 95% CI, 1%-6%) patients allocated to surgery and endovascular treatments, respectively. Neurologic deficits (32/143, 22%; 95% CI, 16%-30% versus 19/148, 12%; 95% CI, 8%-19%; relative risk: 1.74; 95% CI, 1.04-2.92; P = .04) and hospitalizations beyond 5 days (69/143, 48%; 95% CI, 40%-56% versus 12/148, 8%; 95% CI, 5%-14%; relative risk: 0.18; 95% CI, 0.11-0.31; P < .001) were more frequent after surgery.

CONCLUSIONS

Surgical clipping is more effective than endovascular treatment of unruptured intracranial aneurysms in terms of the frequency of the primary outcome of treatment failure. Results were mainly driven by angiographic results at 1 year.

Mitochondrial control of microglial phagocytosis by the translocator protein and hexokinase 2 in Alzheimer's disease

Microglial phagocytosis is an energetically demanding process that plays a critical role in the removal of toxic protein aggregates in Alzheimer's disease (AD). Recent evidence indicates that a switch in energy production from mitochondrial respiration to glycolysis disrupts this important protective microglial function and may provide therapeutic targets for AD. Here, we demonstrate that the translocator protein (TSPO) and a member of its mitochondrial complex, hexokinase-2 (HK), play critical roles in microglial respiratory-glycolytic metabolism and phagocytosis. Pharmacological and genetic loss-of-function experiments showed that TSPO is critical for microglial respiratory metabolism and energy supply for phagocytosis, and its expression is enriched in phagocytic microglia of AD mice. Meanwhile, HK controlled glycolytic metabolism and phagocytosis via mitochondrial binding or displacement. In cultured microglia, TSPO deletion impaired mitochondrial respiration and increased mitochondrial recruitment of HK, inducing a switch to glycolysis and reducing phagocytosis. To determine the functional significance of mitochondrial HK recruitment, we developed an optogenetic tool for reversible control of HK localization. Displacement of mitochondrial HK inhibited glycolysis and improved phagocytosis in TSPO-knockout microglia. Mitochondrial HK recruitment also coordinated the inflammatory switch to glycolysis that occurs in response to lipopolysaccharide in normal microglia. Interestingly, cytosolic HK increased phagocytosis independent of its metabolic activity, indicating an immune signaling function. Alzheimer's beta amyloid drastically stimulated mitochondrial HK recruitment in cultured microglia, which may contribute to microglial dysfunction in AD. Thus, targeting mitochondrial HK may offer an immunotherapeutic approach to promote phagocytic microglial function in AD.

Mitoprotective Effects of Centella asiatica (L.) Urb.: Anti-Inflammatory and Neuroprotective Opportunities in Neurodegenerative Disease

Natural products remain a crucial source of drug discovery for accessible and affordable solutions for healthy aging. Centella asiatica (L.) Urb. (CA) is an important medicinal plant with a wide range of ethnomedicinal uses. Past in vivo and in vitro studies have shown that the plant extract and its key components, such as asiatic acid, asiaticoside, madecassic acid and madecassoside, exhibit a range of anti-inflammatory, neuroprotective, and cognitive benefits mechanistically linked to mitoprotective and antioxidant properties of the plant. Mitochondrial dysfunction and oxidative stress are key drivers of aging and neurodegenerative disease, including Alzheimer’s disease and Parkinson’s disease. Here we appraise the growing body of evidence that the mitoprotective and antioxidative effects of CA may potentially be harnessed for the treatment of brain aging and neurodegenerative disease.

Acute application of Centella asiatica extract enhanced AMPAR-mediated postsynaptic currents in rat entorhinal cortex

Centella asiatica is notable for its wide range of biological activities beneficial to human health, particularly its cognitive enhancement and neuroprotective effects. The α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors are ionotropic glutamate receptors mediating fast excitatory neurotransmission essential in long-term potentiation widely thought to be the cellular mechanism of learning and memory. The method of whole-cell patch-clamp was used to study the effect of the acute application of Centella asiatica extract on the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor-mediated spontaneous excitatory postsynaptic currents in the entorhinal cortex of rat brain slices. The respective low dose of test compounds significantly increased the amplitude of spontaneous excitatory postsynaptic currents while having no significant effects on the frequency. The findings suggested that Centella asiatica extract increased the response of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors at the postsynaptic level, revealing the potential role of Centella asiatica in modulating the glutamatergic responses in the entorhinal cortex of rat brain slices to produce cognitive enhancement effects.

Role of toll-like receptor 4 antagonist Lipopolysaccharide-Rhodobacter sphaeroides on acute stress-induced voluntary ethanol preference and drinking behaviour: In vivo Swiss Albino mouse model

The present study focused on investigating the effect of toll-like receptor 4 (TLR4) antagonist Lipopolysaccharide-Rhodobacter sphaeroides(LPS-RS) on acute, stress-induced voluntary ethanol preference and drinking behaviour, neuronal components activation, and gene expression associated with stress and addictive behaviour. This study involved the exposure of restraint stress and social isolation using Swiss Albino mice. Two-bottle choice ethanol preference analysis was used in the evaluation of voluntary ethanol seeking and drinking behaviour. Several behavioural assessments were carried out to assess fear and anxiety-like behaviour, neuromuscular ability, motor coordination and locomotion. Morphological and immunoreactivity analysis and gene expression analysis were done after the completion of behavioural assessments. TLR4 antagonist LPS-RS treated stressed-mice showed a significant decrease in ethanol drinking compared with stressed mice. Behavioural results showed that stress exposure induced fear and anxiety-like behaviour; however; no significant deficit was found on motor coordination, neuromuscular ability, locomotion and exploratory behaviour among groups. Morphological analysis showed no significant change in the prefrontal cortex and hippocampus among all groups, while immunoreactivity analysis showed higher expression of c-Fos in prefrontal cortex and hippocampus, higher TLR4 expression in the prefrontal cortex and glial fibrillary acidic protein (GFAP) in hippocampus among stressed-animals. Stressed-mice also showed significant increase in TLR4, Nuclear Factor-Kappa B (NF-kB), inducible nitric oxide synthase (iNOS), dopamine receptor D2 (DRD₂), cyclic adenosine monophosphate (cAMP) response element binding protein-1 (CREB-1) and opioid receptor MU-1 (OPRM-1) genes expression compared with control and LPS-RS treated stressed-mice. As a conclusion, the antagonism of TLR4 could provide therapeutic value in the treatment of stress-induced addiction.

Mitochondrial Regulation of Microglial Immunometabolism in Alzheimer's Disease

Alzheimer’s disease (AD) is an age-associated terminal neurodegenerative disease with no effective treatments. Dysfunction of innate immunity is implicated in the pathogenesis of AD, with genetic studies supporting a causative role in the disease. Microglia, the effector cells of innate immunity in the brain, are highly plastic and perform a diverse range of specialist functions in AD, including phagocytosing and removing toxic aggregates of beta amyloid and tau that drive neurodegeneration. These immune functions require high energy demand, which is regulated by mitochondria. Reflecting this, microglia have been shown to be highly metabolically flexible, reprogramming their mitochondrial function upon inflammatory activation to meet their energy demands. However, AD-associated genetic risk factors and pathology impair microglial metabolic programming, and metabolic derailment has been shown to cause innate immune dysfunction in AD. These findings suggest that immunity and metabolic function are intricately linked processes, and targeting microglial metabolism offers a window of opportunity for therapeutic treatment of AD. Here, we review evidence for the role of metabolic programming in inflammatory functions in AD, and discuss mitochondrial-targeted immunotherapeutics for treatment of the disease.

Enhancing Education to Avoid Complications in Endovascular Treatment of Unruptured Intracranial Aneurysms: A Neurointerventionalist's Perspective

It is of utmost importance to avoid errors and subsequent complications when performing neurointerventional procedures, particularly when treating low-risk conditions such as unruptured intracranial aneurysms. We used endovascular treatment of unruptured intracranial aneurysms as an example and took a survey-based approach in which we reached out to 233 neurointerventionalists. They were asked what they think are the most important points staff should teach their trainees to avoid errors and subsequent complications in endovascular treatment of unruptured intracranial aneurysms. One hundred twenty-one respondents (51.9%) provided answers in the form of free text responses, which were thematically clustered in an affinity diagram and summarized in this Practice Perspectives. The article is primarily intended for neurointerventional radiology fellows and junior staff and will hopefully provide them the opportunity to learn from the mistakes of their more experienced colleagues.

Abstract P5-11-12: Longitudinal changes in volumetric breast density and fibroglandular volume with endocrine therapy in African American women with estrogen receptor positive breast cancer

Background and Aim:

Reduction in breast density has been proposed as a biomarker of response to endocrine therapy (ET). The vast majority of current data are derived from white or Asian women. Because baseline breast density is associated with race, it is possible that changes in breast density with treatment may also be affected by race. Our objective was to assess the impact of ET on volumetric breast density (VBD) and fibroglandular volume (FGV) in African American (AA) women with invasive breast cancer.

Methods:

We conducted a retrospective study of AA women diagnosed with estrogen receptor positive invasive breast cancer at our institution from 2009-2013. Mammograms within two years prior to diagnosis and at least 6 months post-diagnosis were utilized for comparing density measurements. Using Volpara automated software, VBD and FGV were measured for the contralateral normal breast by averaging the respective values measured on the craniocaudal and mediolateral oblique views.

Results:

51 women met the inclusion criteria and were confirmed to have received ET. Sixteen women received tamoxifen, 34 received an aromatase inhibitor, and medication data was unavailable in one case. The mean age at diagnosis was 56 years (range 29-72, median 55). 53% of women had stage I disease, 29% had stage II disease, and 18% had stage III disease. The majority of women had ER+ PR+ HER2 - disease (82.4%). 53.0% of women received systemic chemotherapy and all but one woman were treated surgically. Average body mass index (BMI) at diagnosis was 36.5, with data not available for 22 women. The mean time between diagnosis and baseline mammogram was 32 days, and the mean time between follow-up mammogram and baseline mammogram was 401 days. Average BMI at one year follow up was 33.7, with data not available for 19 women. The mean baseline VBD was 7.5% (range 1.9-21.5%, median 6.3%) and the mean follow-up VBD was 6.9% (range 2.0-23.6%, median 5.6%). Fifteen women had a longitudinal increase in VBD. The mean absolute change in VBD was -0.6% (range -3.4% to +9.8%, median 0.7%), with a mean 8.0 percent decrease from baseline to follow-up (range -0.7 to +0.5, median 0.1). The mean baseline FGV was 72.3 cm3 (range 18.5-208.4, median 65.3) and the mean follow-up FGV was 69.7 cm3 (range 22.7-197.5, median 60.5). Nineteen women had a longitudinal increase in FGV. The mean absolute reduction in FGV was 2.6 cm3 (range -53.3 to 49.3, median 4.8), with a mean 0.9 percent decrease from baseline to follow-up (range -111.6 to +53.0, median 5.2).

Conclusions:

We observed an overall decrease in Volpara-calculated VBD and FGV in our cohort of AA women treated with ET. It remains to be determined whether changes in VBD and FGV across serial mammograms may be a biomarker for response to ET in women of all races. Large prospective studies are needed to evaluate the effects of ET on longitudinal changes in VBD and FGV while controlling for confounders such as menopausal status, BMI, and chemotherapy.

Citation Format: Johnson HM, Shivalingappa H, Wong JH, Muzaffar M, Verbanac K, Vohra NA. Longitudinal changes in volumetric breast density and fibroglandular volume with endocrine therapy in African American women with estrogen receptor positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-11-12.

Hippocampal amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid GluA1 (AMPA GluA1) receptor subunit involves in learning and memory improvement following treatment with Centella asiatica extract in adolescent rats

INTRODUCTION

Centella asiatica is an herbal plant that contains phytochemicals that are widely believed to have positive effects on cognitive function. The adolescent stage is a critical development period for the maturation of brain processes that encompass changes in physical and psychological systems. However, the effect of C. asiatica has not been extensively studied in adolescents. The aim of this study was therefore to investigate the effects of a C. asiatica extract on the enhancement of learning and memory in adolescent rats.

METHODS

The locomotor activity, learning, and memory were assessed by using open field test and water T-maze test. This study also examined changes in neuronal cell morphology using cresyl violet and apoptosis staining. We also performed immunohistochemical study to analyse the expression of the glutamate AMPA receptor (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) GluA1 subunit and the GABA receptor (γ-Aminobutyric Acid) subtype GABA_A α1 subunit in the hippocampus of the same animals.

RESULTS

We found no significant changes in locomotor activity (p > 0.05). The water T-maze data showed that 30 mg/kg dose significantly (p < 0.05) improved learning, memory, and the memory consolidation phase but had no effect on reversal learning (p > 0.05). Histological data revealed no neuronal morphological changes. Immunohistochemical analysis revealed increased expression of the AMPA GluA1 receptor subunit but there was no effect on GABA_A receptor α1 subunit expression in the CA1 and CA2 subregions of the hippocampus.

CONCLUSIONS

The C. asiatica extract therefore improved hippocampus-dependent spatial learning and memory in a dose-dependent manner in rats through the GluA1-containing AMPA receptor in the CA1 and CA2 sub regions of the hippocampus.

The Effects of 4-Hydroxybenzoic Acid Identified from Bamboo (Dendrocalamus asper) Shoots on Kv1.4 Channel

Background

Bamboo shoot has been used as a treatment for epilepsy in traditional Chinese medicine for generations to treat neuronal disorders such as convulsive, dizziness and headaches. 4-hydroxybenzoic acid (4-hba) is a non-flavonoid phenol found abundantly in Dendrocalamus asper shoots (bamboo), fruits (strawberries and apples) and flowers. Kv1.4 is a rapidly inactivating Shaker-related member of the voltage-gated potassium channels with two inactivation mechanisms; the fast N-type and slow C-type. It plays vital roles in repolarisation, hyperpolarisation and signaling the restoration of resting membrane potential through the regulation of the movement of K⁺ across the cellular membrane.

Methods

Chemical compounds from Dendrocalamus asper bamboo shoots were purified and identified as major palmitic acids mixed with other minor fatty acids, palmitic acid, 4-hydroxybenzaldehyde, lauric acid, 4-hydroxybenzoic acid and cholest-4-ene-3-one. The response of synthetic 4-hydroxybenzoic acid was tested on Kv1.4 potassium channel which was injected into viable oocytes that was extracted from Xenopus laevis. The current were detected by the two-microelectrode voltage clamp, holding potential starting from -80 mV with 20 mV step-up until +80 mV. Readings of treatments with 0.1% DMSO, 4-hba concentrations and K channel blockers were taken at +60 mV. The ratio of tail/peak amplitude is the index of the activity of the Kv1.4 channels with n ≥ 6 (number of oocytes tested). The decreases of the ratios of five different concentrations (1 μM, 10 μM, 100 μM, 1 mM and 2.5 mM) were compared with 0.1% DMSO as the control.

Results

All concentration showed statistically significant results with P < 0.05 except for 100 μM. The normalised current of the 4-hba concentrations were compared with potassium channel blockers (TEA and 4-AP) and all groups showed statistically significant results. This study also showed that time taken for each concentration to affect Kv1.4 does not play any significant roles.

Conclusion

4-hydroxybenzoic acid was found to be able to enhance the inactivation of Kv1.4 by lowering the membrane potential so that the abnormal neuronal firing can be inhibited. With IC50 slightly higher than 10 μM, increasing concentrations (100 μM, 1 mM and 2.5 mM) had shown to exhibit toxicity effects. The best concentration from this study is 10 μM with Hill slope of 0.1799.

Abstract P6-08-21: Early breast cancer-specific mortality in women with early stage breast cancer: Epidemiological and clinical characteristics

Background and Aim:

The five-year survival for women with stage I-II breast cancer is 93-100%. Despite standard of care treatment, a small subset of these women suffer early breast cancer-specific mortality and die within 12 months of diagnosis. This subset of women has not been previously described. The aim of this study is to characterize the incidence, demographics, and clinical characteristics of women with early stage breast cancer who suffer early breast cancer-specific mortality.

Methods:

Retrospective population study of the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) registry of women diagnosed with stage I, IIA, or IIB breast cancer between 2004 and 2010. Data were filtered to histology codes 8500-8543 and 8575. Patient demographics (age, race, ethnicity) and clinical characteristics (stage, T stage, N stage, grade, ER status, PR status) of women in the early mortality subset were compared with those of women who survived &gt; 12 months via the Chi-square test and the student t-test.

Results:

259,380 women formed the basis of our analysis. 4,572 women (0.018%) died within 12 months of diagnosis. Compared with those who survived &gt; 12 months, women who suffered early breast cancer-specific mortality were on average older (mean age 65.7 years versus 60.3 years, p&lt;0.00001) and more likely to be Hispanic (14.3% versus 8.9%, p&lt;0.00001) or black (11.0% versus 9.1%, p&lt;0.00001). Clinical characteristics associated with early mortality included higher stage (stage IIA 34.2% versus 29.4%, stage IIB 21.8% versus 12.9%, p&lt;0.00001), higher T stage (T2 40.5% versus 28.1%, T3 3.1% versus 1.6%, p&lt;0.00001), higher N stage (N1 29.7% versus 23.2%, N2 0.8% versus 0.4%, N3 0.4% versus 0.1%, p&lt;0.00001), higher grade (moderate 39.3% versus 42.5%, high 40.0% versus 31.5%, p&lt;0.00001), higher rates of ER negativity (27.2% versus 19.0%, p&lt;0.00001), and higher rates of PR negativity (38.5% versus 30.2%, p&lt;0.00001).

Conclusions:

Breast cancer-specific mortality within 12 months of diagnosis of stage I-II breast cancer is a rare phenomenon which has not been previously characterized. There are several demographic and clinical features associated with early mortality, however further research is needed to identify specific prognostic factors that will allow identification of women at risk for early mortality at the time of diagnosis.

Citation Format: Johnson HM, Wong JH, Vohra NA, Muzaffar M. Early breast cancer-specific mortality in women with early stage breast cancer: Epidemiological and clinical characteristics [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-08-21.

The Effect of 4-hydroxybenzaldehyde on the γ-aminobutyric Acid Type A Receptor

The α₁β₂γ₂ subtype of GABA_A receptors is the most commonly found GABA_A receptor subtype in the mammalian cortex and hippocampus. It is expressed heterologously in the Xenopus laevis oocyte as a α₁β₂γ₂S/L subtype for application as an in vitro model for the screening of compounds that modulate receptor activities. In fact, 4-hydroxybenzaldehyde (4-HB) has been identified as one of the major components in Dendrocalamus asper bamboo shoots in our previous study, and the current study showed that at 101.7 μM, 4-HB significantly reduced the GABA-induced chloride current of GABA_A receptors expressed on Xenopus oocytes, indicating a possible GABAergic antagonistic effect at high concentrations.

Abstract P6-09-26: Effect of race on triple negative breast cancer outcomes

Background: African American (AA) women and patients with Triple Negative Breast Cancer (TNBC) have poor outcomes. It is unclear whether these worse outcomes in AA women are due to a higher frequency of TNBC in AA women. The purpose of our study was to determine difference in outcomes between AA and Caucasian (CA) female with TNBC.

Methods: A retrospective study of women diagnosed with ER, PR and HER2 (1+) negative breast cancer between January 1/2001 and December 31/2013 at Vidant Medical Center (East Carolina University) in Greenville, North Carolina was undertaken. Patient demographics and tumor characteristics were analyzed to determine impact on overall survival.

Results: In our institution, 4,434 women were diagnosed with breast cancer in this study period, of which 378 had TNBC. Our TNBC population was predominantly AA (53%). AA patients were younger (54.1 years vs 58.7 years, p=0.005), less often postmenopausal (62.6% vs 74.5%, p=0.013), more likely to have Medicaid (24.3% vs 7.9%, p &lt;0.001), and to have received chemotherapy (80% vs 69%, p=0.017) compared to CA women. There was no difference in stage at diagnosis between AA and CA patients (p=0.12). By univariate analysis, improved survival in TNBC was associated with non-Medicaid status (p=0.01), early stage at diagnosis (p=0.001), N stage (&lt;0.001), and tumor grade (p&lt;0.001). A Cox regression analysis demonstrated that only insurance status (p=0.007) and N Stage (p=0.01) predicted outcomes in TNBC. Survival in TNBC was not affected by race (p=0.7).

Conclusions: Poorer outcomes in AA women cannot be attributed to the higher frequency of TNBC. Improved access to healthcare, with broader insurance coverage, may help minimize disparities in outcome by diagnosing TNBC at an earlier stage.Background: African American (AA) women and patients with Triple Negative Breast Cancer (TNBC) have poor outcomes. It is unclear whether these worse outcomes in AA women are due to a higher frequency of TNBC in AA women. The purpose of our study was to determine difference in outcomes between AA and Caucasian (CA) female with TNBC.

Methods: A retrospective study of women diagnosed with ER, PR and HER2 (1+) negative breast cancer between January 1/2001 and December 31/2013 at Vidant Medical Center (East Carolina University) in Greenville, North Carolina was undertaken. Patient demographics and tumor characteristics were analyzed to determine impact on overall survival.

Results: In our institution, 4,434 women were diagnosed with breast cancer in this study period, of which 378 had TNBC. Our TNBC population was predominantly AA (53%). AA patients were younger (54.1 years vs 58.7 years, p=0.005), less often postmenopausal (62.6% vs 74.5%, p=0.013), more likely to have Medicaid (24.3% vs 7.9%, p &lt;0.001), and to have received chemotherapy (80% vs 69%, p=0.017) compared to CA women. There was no difference in stage at diagnosis between AA and CA patients (p=0.12). By univariate analysis, improved survival in TNBC was associated with non-Medicaid status (p=0.01), early stage at diagnosis (p=0.001), N stage (&lt;0.001), and tumor grade (p&lt;0.001). A Cox regression analysis demonstrated that only insurance status (p=0.007) and N Stage (p=0.01) predicted outcomes in TNBC. Survival in TNBC was not affected by race (p=0.7).

Conclusions: Poorer outcomes in AA women cannot be attributed to the higher frequency of TNBC. Improved access to healthcare, with broader insurance coverage, may help minimize disparities in outcome by diagnosing TNBC at an earlier stage.

Citation Format: Mosquera C, Amin R, Wong JH. Effect of race on triple negative breast cancer outcomes [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-26.

Recent studies on the antimicrobial peptides lactoferricin and lactoferrampin

Lactoferricin and lactoferrampin, peptides derived from the whey protein lactoferrin, are antimicrobial agents with a promising prospect and are currently one of the research focuses. In this review, a basic introduction including location and solution structures of these two peptides is given. Their biological activities encompassing antiviral, antibacterial, antifungal and anti-inflammatory activities with possible mechanisms are mentioned. In terms of modification studies, research about identification of their active derivatives and crucial amino acid residues is also discussed. Various attempts at modification of lactoferricin and lactoferrampin such as introducing big hydrophobic side-chains; employing special amino acids for synthesis; N-acetylization, amidation, cyclization and peptide chimera are summarized. The studies on lactoferricin-lactoferrampin chimera are discussed in detail. Future prospects of lactoferricin and lactoferrampin are covered.

Abstract P1-09-12: The interplay of biologic factors, race, and delivery of care in improving breast cancer outcomes

Importance: A marked disparity exists in the breast cancer mortality of women diagnosed in Eastern North Carolina (ENC) when compared to women diagnosed in the rest of North Carolina (RNC).

Objective: To identify modifiable factors associated with the increased mortality of women diagnosed with breast cancer in ENC.

Design: Retrospective cohort study of women diagnosed with breast cancer in North Carolina between January 1, 2004 and December 31, 2007.

Setting: North Carolina Central Cancer Registry.

Participants: Females diagnosed with either invasive or non-invasive breast cancer in North Carolina during the designated time period.

Main Outcome Measures: Race/ethnicity, hormone receptor status, pathologic T, N and stage grouping at the time of diagnosis, delivery of adjuvant chemotherapy, and survival.

Results: A total of 27,631 women were diagnosed with breast cancer during the study period. Women in ENC were slightly older than in RNC (59.2 y v. 58.5 y, p&lt;0.001). There was no difference in the pathologic T (p = 0.62), N (p = 0.26) or Stage Grouping (p = 0.25) at diagnosis between ENC and RNC patients. Women in ENC were less likely to be White (68.9% v. 80.0%, &lt;0.001)), ER positive (53.4% v. 59.4%, p&lt;0.001), PR positive (44.8% v. 49.4%, p&lt;0.001), or to receive adjuvant chemotherapy (78.7% v. 81.3%, p = 0.02). The median survival of ENC patients was significantly worse than RNC patients (39 months v. 43 months, p = 0.003). By univariate analysis, improved median survival was associated with ER status (p&lt;0.001), PR status (p&lt;0.001), Race/ethnicity (p&lt;0.001) and delivery of timely chemotherapy (p&lt;0.0001). By Cox Regression analysis, ER negative status (RR 1.03; 95% CI 0.85 to 0.98, p = 0.01), African American (RR 0.94; 95% CI 0.89 to 0.99, p = 0.03), and adjuvant chemotherapy within 90 days of surgery (RR 1.40; 95% CI 1.30 to 1.50, p&lt;0.001) remained significant predictors of survival.

Conclusions: The poor outcomes observed in ENC can be attributed to recognized prognostic primary patient and tumor characteristics. However a failure in process of care remains significantly associated with poorer outcomes. Improved timing of delivery of chemotherapy could affect breast cancer mortality.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-09-12.

Mechanical thrombectomy with the Solitaire stent: is there a learning curve in achieving rapid recanalization times?

METHODS

In acute ischemic stroke, good outcome following successful recanalization is time dependent. In patients undergoing endovascular therapy at our institution, recanalization times with the Solitaire stent were retrospectively evaluated to assess for the presence of a learning curve in achieving rapid recanalization.

METHODS

We reviewed patients who presented to our stroke center and achieved successful recanalization with the Solitaire stent exclusively. Time intervals were calculated (CT to angiography arrival, angiography arrival to groin puncture, groin puncture to first deployment, and deployment to recanalization) from time stamped images and angiography records. Patients were divided into three sequential groups, with overall CT to recanalization time and subdivided time intervals compared.

RESULTS

83 patients were treated with the Solitaire stent from May 2009 to February 2012. Recanalization (Thrombolyis in Cerebral Infarction score 2A) occurred in 75 (90.4%) patients. CT to recanalization demonstrated significant improvement over time, which was greatest between the first 25 and the most recent 25 cases (161-94 min; p<0.01). The maximal contribution to this was from improvements in first stent deployment to recanalization time (p=0.001 between the first and third groups), with modest contributions from moving patients from CT to the angiography suite faster (p=0.02 between the first and third groups) and from groin puncture to first stent deployment (p=0.02 between the first and third groups).

CONCLUSIONS

There is a learning curve involved in the efficient use of the Solitaire stent in endovascular acute stroke therapy. Along with improvements in patient transfer to angiography and improved efficiency with intracranial access, mastering this device contributed significantly towards reducing recanalization times.

When is carotid angioplasty and stenting the cost-effective alternative for revascularization of symptomatic carotid stenosis? A Canadian health system perspective

BACKGROUND AND PURPOSE

Carotid revascularization procedures can be complicated by stroke. Additional disability adds to the already high costs of the procedure. To weigh the cost and benefit, we estimated the cost-utility of carotid angioplasty and stenting compared with carotid endarterectomy among patients with symptomatic carotid stenosis, with special emphasis on scenario analyses that would yield carotid angioplasty and stenting as the cost-effective alternative relative to carotid endarterectomy.

MATERIALS AND METHODS

A cost-utility analysis from the perspective of the health system payer was performed by using a Markov analytic model. Clinical estimates were based on a meta-analysis. The procedural costs were derived from a microcosting data base. The costs for hospitalization and rehabilitation of patients with stroke were based on a Canadian multicenter study. Utilities were based on a randomized controlled trial.

RESULTS

In the base case analysis, carotid angioplasty and stenting were more expensive (incremental cost of $6107) and had a lower utility (-0.12 quality-adjusted life years) than carotid endarterectomy. The results are sensitive to changes in the risk of clinical events and the relative risk of death and stroke. Carotid angioplasty and stenting were more economically attractive among high-risk surgical patients. For carotid angioplasty and stenting to become the preferred option, their costs would need to fall from more than $7300 to $4350 or less and the risks of the periprocedural and annual minor strokes would have to be equivalent to that of carotid endarterectomy.

CONCLUSIONS

In the base case analysis, carotid angioplasty and stenting were associated with higher costs and lower utility compared with carotid endarterectomy for patients with symptomatic carotid stenosis. Carotid angioplasty and stenting were cost-effective for patients with high surgical risk.

Pipeline embolization device in aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The PED is an FDS designed for the treatment of intracranial aneurysms. Data regarding the use of this device in acute or subacute aSAH is limited to a few case reports or small series. We aimed to demonstrate the feasibility of using an FDS, the PED, for the treatment of ruptured intracranial aneurysms with challenging morphologies.

MATERIALS AND METHODS

We conducted a retrospective review of all known patients treated with the PED for aSAH at 4 institutions between June 2008 and January 2012. Pertinent clinical and radiologic information was submitted by individual centers for central collation. The decision to treat with the PED was made on a case-by-case basis by a multidisciplinary team under compassionate use.

RESULTS

Twenty patients (15 women; median age, 54.5 years; IQR, 8.0 years) were found. There were 8 blister, 8 dissecting or dysplastic, 2 saccular, and 2 giant aneurysms. Median time to treatment was 4 days (range, 1-90 days; IQR, 12.75 days) from rupture. Three patients had previous failed treatment. Procedure-related symptomatic morbidity and mortality were 15%, with 1 (5%) procedure-related death. Two patients died relative to medical complications, and 1 patient was lost to follow-up. Sixteen patients were available for follow-up, 81% had a GOS of 5, and 13% had a GOS of 4 attributed to a poorer initial clinical presentation. One patient died of urosepsis at 4 months. Occlusion rates were 75% and 94% at 6 months and 12 months, respectively. There were 3 delayed complications (1 silent perforator infarct, 2 moderate asymptomatic in-stent stenoses). No symptomatic delayed complications or rehemorrhages occurred.

CONCLUSIONS

The FDS may be a feasible treatment option in the acute or subacute setting of selected ruptured aneurysms, especially blister aneurysms. Ruptured giant aneurysms remain challenging for both surgical and endovascular techniques; at this stage, FDSs should be used with caution in this aneurysm subtype.

Fungal proteins with antiproliferative and anticancer activities

Fungi produce a variety of proteins with antiproliferative activity toward tumor cells and anticancer activity in tumor bearing mice. The aforementioned fungal proteins include ribonucleases, antifungal proteins, ubiquitin-like peptides, ribosome inactivating proteins, hemolysins, hemagglutinins/lectins, laccases, and protein-bound polysaccharopeptides.

Balloon-assisted rapid intermittent sequential coiling (BRISC) technique for the treatment of complex wide-necked intracranial aneurysms

We describe our experience with balloon-assisted rapid intermittent sequential coiling (BRISC) of complex wide-necked aneurysms as an alternative to stent-assisted coiling. We use this technique in patients with acutely ruptured aneurysms, where antithrombotic treatment prior to stent deployment may not be advisable, and where the vascular anatomy is unfavorable for stenting. This is a retrospective analysis of 11 wide-necked aneurysms treated with this technique from June 2008 to January 2010. Results were analyzed in terms of aneurysm occlusion, procedural complications like thromboembolism, dissection/vasospasm, groin hematoma and any recurrence on follow-up. Coiling was successfully attempted in all cases (100%). Immediate angiographic results showed complete occlusion (class 1) in 8/11, residual neck (class II) in 3/11 and no residual aneurysm (class III). Procedural complications were local thrombus formation in 3/11 procedures but no symptomatic thromboembolism, dissection in 1/11 and groin hematoma in 1/11. There was no morbidity or mortality. On follow-up study, there was one recurrence, which was subsequently coiled. In our opinion, this technique may provide an alternative to stent-assisted coiling in patients with ruptured aneurysm where antithrombotic treatment prior to stent deployment may not be advisable and in the presence of vascular anatomy unsuitable for stenting.

Isolation of adenosine, iso-sinensetin and dimethylguanosine with antioxidant and HIV-1 protease inhibiting activities from fruiting bodies of Cordyceps militaris

According to previous studies, a close relationship between oxidative stress and AIDS suggests that antioxidants might play an important role in the treatment of AIDS. Cordyceps militaris was selected from nine edible mushrooms by assay of inhibition of erythrocyte hemolysis. Macroporous adsorption resin and HPLC were used to purify three micromolecular compounds named L3a, L3b and L3c. L3a was identified to be adenosine with the molecular formula C(10)H(13)N(5)O(4); L3b was 6,7,2',4',5'-pentamethoxyflavone with the molecular formula C(20)H(20)O(7), and L3c was dimethylguanosine with the molecular formula C(12)H(17)N(5)O(5). The compound 6,7,2',4',5'-pentamethoxyflavone was first isolated from C. militaris. The assay of inhibition of HIV-1 protease (HIV-1 PR) was based on the fact that the expression of this enzyme can inhibit the growth of E. coli. This is a new screening system for HIV-1 PR inhibitors. Both L3a and L3b showed high inhibition to HIV-1 PR. These compounds could be new anti-HIV-1 PR drugs.

Fusiform lenticulostriate artery aneurysm with subarachnoid hemorrhage: the role for superselective angiography in treatment planning

Aneurysms of the lenticulostriatal perforating arteries are rare and either involve the middle cerebral artery-perforator junction or are located distally in basal ganglia. We describe a rare ruptured fusiform lenticulostriatal perforating artery aneurysm arising from a proximal M2 MCA branch, discerned on superselective microcatheter angiography, presenting solely with subarachnoid hemorrhage (SAH). A 50-year-old previously healthy man presented with diffuse SAH and negative CT angiogram. Cerebral angiogram demonstrated a 2 mm fusiform aneurysm presumably arising from the right lateral lenticulostriate perforator but the exact origin of the perforator was unclear. Superselective angiography was required to precisely delineate the aneurysm and its vessel of origin and directly influenced treatment planning (surgical trapping). Superselective microcatheter angiography provides both an option for endovascular therapy as well as more accurate delineation for surgical planning for these rare aneurysms.

Biochemical and functional properties of a lectin purified from korean large black soybeans--a cultivar of glycine max

Lectins, a class of proteins that reversibly and non-enzymatically bind specific sugars, have been purified from different kinds of legumes. In this study, a 48-kDa lectin (KBL) was purified from Korean large black soybeans using liquid chromatography. The specific hemagglutinating activity of the KBL was 4096 titer/mg. EDTA-induced loss of hemagglutinating activity of KBL could be recovered by addition of Fe(3+) ions and some divalent cations as Ca(2+), Mn(2+), Fe(2+), Cu(2+), Zn(2+), and Pb(2+). Sugars such as D-(+)-galactose, D-(+)-raffinose, L-(+)-arabinose, alpha-D-(+)-melibiose, and alpha-lactose could inhibit the hemagglutinating activity of the lectin. Furthermore, the protein showed high thermal stability as well as stability over a wide range of pH values. KBL inhibited HIV-1 reverse transcriptase activity with an IC(50) of 1.38 microM. However, it was destitute of cytokine releasing, mitogenic, ribonuclease and antifungal activities. In addition, inhibitory activity toward nasopharyngeal cell lines was undetectable in KBL at concentrations up to 20 microM.

Stimulatory effect of components of rose flowers on catalytic activity and mRNA expression of superoxide dismutase and catalase in erythrocytes

In the present study, two antioxidant components (polysaccharopeptide complex P(1-a) and condensed tannin P(1-b)) from rose (Rosa rugosa) flowers were each incubated with mouse erythrocytes to investigate their effect on erythrocyte superoxide dismutase (SOD), and catalase (CAT) activities. It was found that the activities of Cu, Zn-SOD and CAT were markedly increased after incubation for 3h with rose flower fractions at the concentration of 500μg/ml. Similar changes were also observed in the erythrocyte gene expression of SOD and CAT. These results show that P(1-a) and P(1-b) are effective antioxidants that increase the activity and the gene expression of SOD and CAT in mouse erythrocytes.

Ossification of the posterior longitudinal ligament

A 51-year-old gentleman of Chinese descent presented for neurological evaluation following a two-year history of cervical neck pain associated with left arm numbness. His symptoms were initially stable, but had progressed over the past six months to include weakness of his entire left arm and leg and symptoms of bladder urgency. Two weeks prior to presentation, he suffered repeated falls due to worsening gait difficulties. The past medical history was significant for type II diabetes mellitus.

Early experience with sentinel lymph node mapping for Merkel cell carcinoma

Merkel cell or cutaneous neuroendocrine carcinoma is a malignant tumor with a propensity toward local and systemic recurrence. A new surgical technique, intraoperative lymphatic mapping and selective sentinel lymph node dissection (SSLND), has been demonstrated to have a high predictive value for the detection of metastatic disease in the regional lymphatic basin in cutaneous melanoma. The use of this technology may be particularly useful to accurately stage patients with Merkel cell carcinoma (MCC) because this tumor has a frequent propensity toward regional nodal metastases. Intraoperative lymphatic mapping and SSLND were performed on 6 patients with biopsy-proven MCC. Three patients with MCC had positive disease in the sentinel lymph node(s). SSLND is a feasible technique with minimal procedural morbidity to detect clinically occult disease in patients with MCC.

Redox changes accompanying the degradation of seed storage proteins in germinating rice

The mobilization of storage proteins (glutelins) in germinating rice seeds was accompanied by an ordered sequential combination of proteolysis and reduction of disulfide groups. Mobilization was followed by application of non-reducing/reducing two dimensional-PAGE after monobromobimane labeling of the sulfhydryl groups of the proteins in intact seeds.

Multidisciplinary approach to selective sentinel lymph node mapping in breast cancer

Although the role of axillary lymph node dissection is controversial with respect to survival benefits, its role as a staging procedure has been well established since nodal involvement is the most reliable prognostic indicator for patients with breast cancer. Selective sentinel lymph node (SLN) dissection is gaining acceptance as a useful staging procedure because it is minimally invasive and spares approximately 70-80% of the patients a more extensive axillary lymph node dissection. The evolving techniques for selective SLN dissection using blue dye and radiotracer methods are reviewed in this article. Based on the classic definition of the breast lymphatic drainage and recently published articles addressing the issue of peritumoral and intradermal injections, a possible new and simplified approach using intradermal injection may identify the axillary SLN more quickly and reliably. This article emphasizes the importance of a multidisciplinary approach in the identification of SLNs by preoperative lymphoscintigraphy performed by expert nuclear medicine physicians, the intraoperative mapping and harvesting of SLNs by well trained surgeons and the meticulous examination of SLNs by experienced pathologists. Therefore, to achieve the highest rate of accuracy regarding SLN status, it is imperative that a multidisciplinary team with close communication and cooperation be formed. The clinical significance of SLNs will be determined by results from follow-up and clinical trials.

Lymphoscintigraphy in Breast Cancer

A 28-year-old woman with an infiltrating ductal carcinoma in the upper outer quadrant of the left breast diagnosed by excisional biopsy underwent lumpectomy, intraoperative lymphatic mapping, and sentinel node dissection. This was followed by an immediate completion axillary node dissection using a hand-held gamma probe and isosulfan blue to map the lymphatics. Preoperative breast lymphoscintigraphy showed drainage into the axilla and an apparent area of radiocolloid accumulation in the inferior hemisphere of the left breast. Because our protocol called only for removal of axillary sentinel nodes, the inferior hemisphere radiocolloid accumulation was not removed. The patient did not complete local regional therapy with breast irradiation and developed a mass in the inferior hemisphere of the left breast, which on biopsy was shown to be metastatic breast cancer in an intramammary lymph node. This case illustrates the potential value of breast lymphoscintograms to identify unusual sites of lymphatic drainage that may prove to be clinically relevant.

[Genetic factors related to intracranial arteriovenous malformations]

Genetic studies are interesting not only in the diagnosis and screening of new cases within a family harboring a particular disease, but also in understanding the underlying genetic and molecular factors related to that disease. Such studies revealed 3 categories of cerebral arteriovenous malformations in relationship to possible genetic factors. The first one concerns cerebral arteriovenous malformations in relationship to inherited diseases where a genetic support is clearly identified. Hereditary hemorrhagic telangiectasia (Rendu-Osler-Weber disease) represents the most classical picture. The second category corresponds to familial cases of cerebral arteriovenous malformations were several members and relatives of the same family harboring the pathology without clear demonstration of any genetic basis. The third category includes cerebral arteriovenous malformations described in association with neurocutaneous disorders issued from maldevelopment events. Sturge-Weber disease and Wyburn-Mason syndrome best illustrate this category. A review of these categories will help in a better understanding of some genetic issues related to cerebral arteriovenous malformations.

A strategy for the identification of proteins targeted by thioredoxin

Thioredoxins are 12-kDa proteins functional in the regulation of cellular processes throughout the animal, plant, and microbial kingdoms. Growing evidence with seeds suggests that an h-type of thioredoxin, reduced by NADPH via NADP-thioredoxin reductase, reduces disulfide bonds of target proteins and thereby acts as a wakeup call in germination. A better understanding of the role of thioredoxin in seeds as well as other systems could be achieved if more were known about the target proteins. To this end, we have devised a strategy for the comprehensive identification of proteins targeted by thioredoxin. Tissue extracts incubated with reduced thioredoxin are treated with a fluorescent probe (monobromobimane) to label sulfhydryl groups. The newly labeled proteins are isolated by conventional two-dimensional electrophoresis: (i) nonreducing/reducing or (ii) isoelectric focusing/reducing SDS/PAGE. The isolated proteins are identified by amino acid sequencing. Each electrophoresis system offers an advantage: the first method reveals the specificity of thioredoxin in the reduction of intramolecular vs. intermolecular disulfide bonds, whereas the second method improves the separation of the labeled proteins. By application of both methods to peanut seed extracts, we isolated at least 20 thioredoxin targets and identified 5-three allergens (Ara h2, Ara h3, and Ara h6) and two proteins not known to occur in peanut (desiccation-related and seed maturation protein). These findings open the door to the identification of proteins targeted by thioredoxin in a wide range of systems, thereby enhancing our understanding of its function and extending its technological and medical applications.

Ex vivo sentinel node mapping in carcinoma of the colon and rectum

OBJECTIVE

Increasing evidence supports that the sentinel node (SN) is at greatest risk for harboring metastatic disease. This study describes a novel technique to identify the SN in colorectal carcinoma.

METHODS

Within 30 minutes of resection, colorectal specimens were injected submucosally with isosulfan blue in four quadrants. Blue lymphatic channels were identified in the mesentery and followed to the blue-stained SN(s), which were then harvested. The specimen was fixed in formalin and subsequently analyzed in the usual fashion. Blue-stained nodes that were negative by hematoxylin and eosin staining were further analyzed by immunohistochemical staining.

RESULTS

During a 6-month period, 26 patients with adenocarcinoma of the colon and rectum undergoing routine resection were studied. There were 18 men and 8 women ranging in age from 29 to 86 years (median 66). Blue-stained SNs were identified in 24 of 26 specimens. The mean number of SNs identified per patient was 2.8 +/- 1.6. Seventy-three SNs were identified from a total of 479 lymph nodes harvested. The mean number of nodes identified per patient was 18.4 +/-7. A total of 67 lymph nodes in 12 patients were identified by hematoxylin and eosin staining to have evidence of metastatic disease. Fourteen (20%) of these nodes in six patients were stained blue. However, with immunohistochemical staining, only one blue node did not have evidence of metastatic tumor in a lymphatic basin with tumor present. Four patients (29%) whose lymphatic basins were negative by hematoxylin and eosin staining were upstaged by immunohistochemical staining of the SN.

CONCLUSIONS

Ex vivo mapping of the colon and rectum is technically feasible and may provide a useful approach to the ultrastaging of colorectal carcinoma.

A historical perspective on the development of intraoperative lymphatic mapping and selective lymphadenectomy

Intraoperative lymphatic mapping (ILM) and selective lymphadenectomy are revolutionary concepts that, in a short period, have shown the potential to alter dramatically the management of many patients with solid neoplasms. The rapid adaptation of this approach to the staging of solid neoplasms by the surgical oncology community has resulted in an explosion of data. Initially described as a surgical technique in which each surgeon had to climb a learning curve, ILM and selective lymph node dissection (SLND) are now recognized as a multidisciplinary surgical approach to the management of the patient with cutaneous melanoma and breast cancer. The potential values of ILM and SLND are being examined vigorously now in numerous other solid neoplasms.

Sentinel lymph node mapping in colorectal cancer--a review

Sentinel lymph node (SLN) mapping has been found to be highly effective in correctly predicting the nodal status for melanoma and for breast cancer. This study shows that SLN mapping also is highly successful in colorectal cancer, posing minimal cost and no complications. The procedure accurately determines the presence or absence of nodal micrometastasis in more than 96% of cases. This article reviews the in vivo and ex vivo techniques for SLN mapping in colorectal cancer, along with its limitations and pitfalls.

Sentinel lymphadenectomy in breast cancer: university research tool or community practice?

There is considerable controversy regarding the introduction and granting of credentials for sentinel lymphadenectomy in breast cancer. Given the workload of the average general surgeon and current procedural guidelines, two to three years would be required to demonstrate competence before a surgeon might perform sentinel lymphadenectomy without an immediate completion axillary node dissection. This article reviews issues related to the introduction of sentinel lymphadenectomy in the general surgeon's armamentarium.

Future perspectives on selective sentinel lymphadenectomy

Selective sentinel lymphadenectomy is a standard staging procedure for patients with melanoma and is rapidly evolving into a standard procedure for breast cancer. A well-trained, multidisciplinary team is essential for the success of such a procedure. Clinical trials are under way to determine the clinical significance of sentinel lymph nodes in melanoma and breast cancer. The techniques of harvesting are being developed in other solid cancers, such as gynecologic and gastrointestinal cancer. Cellular and molecular techniques are being used to study the mechanism of micrometastasis.

Sentinel lymphadenectomy in gynecologic and solid malignancies other than melanoma and breast cancer

The role of sentinel lymphadenectomy in the management of malignancies other than melanoma and breast cancer is being increasingly explored. Improved staging of solid tumors holds great promise for refining treatment recommendations and gaining insight into the biologic behavior of these malignancies. This article summarizes the growing experiences with sentinel lymphadenectomy in solid tumors other than cutaneous melanoma and breast cancer.

Sentinel node staging for cutaneous melanoma in a university-affiliated community care setting

BACKGROUND

The feasibility of intraoperative lymphatic mapping and sentinel lymphadenectomy (SLND) in settings other than high-volume specialized clinics has been questioned. We sought to determine the feasibility of SLND in a university-affiliated private teaching hospital.

METHODS

A multidisciplinary sentinel node program was established to include surgeons, nuclear medicine physicians, and pathologists. Within this program, 79 patients with cutaneous melanoma underwent attempted SLND after cutaneous lymphoscintigraphy (CL), between January 1994 and December 1998. All sentinel nodes were examined by hematoxylin-eosin staining and determined whether negative for evidence metastatic disease by both S-100 and HMB 45 immunohistochemical staining.

RESULTS

CL was successful in 77 (97%) of 79 patients. A total of 88 lymphatic basins were found to be at risk for metastatic disease by CL. SLND was not successful in the two patients who did not have a successful CL. Sentinel nodes were identified in all but three patients with the remaining 88 lymphatic basins (technical success, 97%). There was one false negative in this group of patients (approximately 1%).

CONCLUSIONS

SLND is a highly accurate way of staging the regional node basin. Our technical success rates and false-negative rates indicate the feasibility of this approach in settings other than high-volume specialty clinics.

Ultrastructural pathological features of cerebrovascular malformations: a preliminary report

OBJECTIVE

Although cerebrovascular malformations have been characterized histologically, a systematic examination of such lesions by transmission electron microscopy has not been previously published. In this preliminary study, we describe the ultrastructural pathological features of cerebral arteriovenous malformations (AVMs) and cavernous malformations (CMs).

METHODS

Using transmission electron microscopy, we examined three CMs and three AVMs microsurgically harvested from patients, for conventional indications. Normal control cerebral tissue was obtained from two patients undergoing surgery for epilepsy. Specific attention was directed at components of the vascular wall, endothelial cell (EC) morphology, intercellular tight junctions, and the subendothelial layer.

RESULTS

In embolized AVM vessels, ECs were disrupted, with preservation of the underlying subendothelial vessel wall. Nidal vessel walls of AVMs showed disorganized collagen bundles. In CM specimens, ECs lined attenuated cavern walls that were composed of an amorphous material lacking organized collagen. Peripheral to the CMs, capillaries were often surrounded by rings of hemosiderin. Tight junctions between ECs were present in AVMs and control specimens, but substantial inter-EC gaps were found in CMs. Subendothelial smooth muscle cells were present in AVM and control specimens, but they were sparse or poorly characterized in CMs.

CONCLUSION

Surgically resected vascular malformations demonstrate abnormal ultrastructural pathological features. The preoperative embolization of AVMs results in EC denudation, with preservation of vessel wall structural integrity. The thin walls of CMs, lacking significant subendothelial support, along with the rarity of intact tight junctions between ECs, may contribute to the known propensity of CMs for recurrent microhemorrhage.

Sedation and general anaesthesia in children undergoing MRI and CT: adverse events and outcomes

Quality assurance data were collected prospectively for children who were sedated (n = 922) or given general anaesthesia (n = 140) for magnetic resonance imaging (MRI) or computerized tomography (CT). The data included patient characteristics, concurrent medication, adequacy of sedation, adverse events and requirement for escalated care. The quality of scans was evaluated. Reasons for preselection of general anaesthesia included previously failed sedation (28%), potential for failed sedation (32%) and perceived medical risk (14%). Hypoxaemia occurred in 2.9% of sedated children, and was more common in children classified as ASA III or IV. Sedation was inadequate for 16% of children and failed in 7%. Failed sedation was associated with greater age (P = 0.009), higher ASA status (P = 0.04) and use of benzodiazepines as sole sedatives (P < 0.03). More of the children who underwent general anaesthesia were ASA III or IV than sedated children, yet the procedure was successful in all the children who underwent general anaesthesia, with one incident of laryngospasm. Excessive motion was noted in 12% of scans of sedated children and 0.7% of those completed with general anaesthesia. We conclude that sedation of children for MRI and CT is associated with risks of hypoxaemia and of inadequate or failed sedation. These adverse events were more likely to occur in older children, those with a higher ASA status and those in whom benzodiazepines had been used as sole sedatives. For a preselected high-risk group of children, general anaesthesia may make MRI and CT scans more successful with minimal adverse events.

Stereotactic computed tomographic-guided aspiration and thrombolysis of intracerebral hematoma : protocol and preliminary experience

BACKGROUND AND PURPOSE

We review preliminary experience with patients harboring intracerebral hematoma (ICH) treated by stereotactic computed tomographic (CT) guided thrombolysis and aspiration and assess procedure feasibility and safety.

METHODS

Twelve patients with supratentorial ICH >/=25 mL without suspected underlying structural etiology or coagulopathy and an initial Glasgow Coma Scale (GCS) score of >/=5 were treated. A catheter was directed stereotactically or manually into the ICH through a burr hole under CT guidance. Hematoma aspiration was followed by instillation of urokinase (5 000 to 10 000 IU). This was repeated every 6 to 8 hours at bedside, with interval CT imaging, until the ICH volume diminished to <25 mL, less than half of its initial volume, or after a maximum of 10 aspirations/instillations.

RESULTS

Mean age was 69 years (range 55 to 82 years). Median initial GCS was 12 (range 5 to 14). There were 7 ganglionic and 5 lobar ICH, and baseline hematoma size ranged 29 to 70 mL (mean 46 mL). Final ICH volume ranged from 14 to 51 mL (mean 21 mL), with ICH volume reduction by an average of 57% (range 38% to 70%). One patient (8. 3%) suffered hematoma expansion during the procedure. At 6 months after the procedure, 3 patients (25%) had achieved a good recovery (Glasgow Outcome Scale [GOS] score of 5), 5 patients (42%) were dependent (GOS 3), and 1 (8.3%) remained vegetative (GOS 2). Three patients (25%) died in hospital (1 from cardiac arrhythmia and 2 from respiratory failure).

CONCLUSIONS

CT-guided thrombolysis and aspiration appears safe and effective in the reduction of ICH volume. Further studies are needed to assess optimal thrombolytic dosage and must include controlled comparisons of mortality, disability outcome, time until convalescence, and cost of care in treated and untreated patients.