Acceleration and transport of relativistic electrons in the jets of the microquasar SS 433

SS 433 is a microquasar, a stellar binary system that launches collimated relativistic jets. We observed SS 433 in gamma rays using the High Energy Stereoscopic System (H.E.S.S.) and found an energy-dependent shift in the apparent position of the gamma-ray emission from the parsec-scale jets. These observations trace the energetic electron population and indicate that inverse Compton scattering is the emission mechanism of the gamma rays. Our modeling of the energy-dependent gamma-ray morphology constrains the location of particle acceleration and requires an abrupt deceleration of the jet flow. We infer the presence of shocks on either side of the binary system, at distances of 25 to 30 parsecs, and that self-collimation of the precessing jets forms the shocks, which then efficiently accelerate electrons.

Search for Dark Matter Annihilation Signals in the H.E.S.S. Inner Galaxy Survey

The central region of the Milky Way is one of the foremost locations to look for dark matter (DM) signatures. We report the first results on a search for DM particle annihilation signals using new observations from an unprecedented γ-ray survey of the Galactic Center (GC) region, i.e., the Inner Galaxy Survey, at very high energies (≳100  GeV) performed with the H.E.S.S. array of five ground-based Cherenkov telescopes. No significant γ-ray excess is found in the search region of the 2014-2020 dataset and a profile likelihood ratio analysis is carried out to set exclusion limits on the annihilation cross section ⟨σv⟩. Assuming Einasto and Navarro-Frenk-White (NFW) DM density profiles at the GC, these constraints are the strongest obtained so far in the TeV DM mass range. For the Einasto profile, the constraints reach ⟨σv⟩ values of 3.7×10^{-26}  cm^{3} s^{-1} for 1.5 TeV DM mass in the W^{+}W^{-} annihilation channel, and 1.2×10^{-26}  cm^{3} s^{-1} for 0.7 TeV DM mass in the τ^{+}τ^{-} annihilation channel. With the H.E.S.S. Inner Galaxy Survey, ground-based γ-ray observations thus probe ⟨σv⟩ values expected from thermal-relic annihilating TeV DM particles.

Time-resolved hadronic particle acceleration in the recurrent nova RS Ophiuchi

Recurrent novae are repeating thermonuclear explosions in the outer layers of white dwarfs, due to the accretion of fresh material from a binary companion. The shock generated when ejected material slams into the companion star's wind can accelerate particles. We report very-high-energy (VHE, [Formula: see text]) gamma rays from the recurrent nova RS Ophiuchi, up to a month after its 2021 outburst, observed using the High Energy Stereoscopic System. The VHE emission has a similar temporal profile to lower-energy GeV emission, indicating a common origin, with a two-day delay in peak flux. These observations constrain models of time-dependent particle energization, favoring a hadronic emission scenario over the leptonic alternative. Shocks in dense winds provide favorable environments for efficient acceleration of cosmic-rays to very high energies.

Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow

Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera-electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios.

Skin Toxicity in Early Breast Cancer Patients Treated with Field-In-Field Breast Intensity-Modulated Radiotherapy versus Helical Inverse Breast Intensity-Modulated Radiotherapy: Results of a Phase III Randomised Controlled Trial

AIMS

Skin toxicity is a common adverse effect of breast radiotherapy. We investigated whether inverse-planned intensity-modulated radiotherapy (IMRT) would reduce the incidence of skin toxicity compared with forward field-in-field breast IMRT (FiF-IMRT) in early stage breast cancer.

MATERIALS AND METHODS

This phase III randomised controlled trial compared whole-breast irradiation with either FiF-IMRT or helical tomotherapy IMRT (HT-IMRT), with skin toxicity as the primary end point. Patients received 50 Gy in 25 fractions and were assessed to compare skin toxicity between treatment arms.

RESULTS

In total, 177 patients were available for assessment and the median follow-up was 73.1 months. Inverse IMRT achieved more homogeneous coverage than FiF-IMRT; erythema and moist desquamation were higher with FiF-IMRT compared with HT-IMRT (61% versus 34%; P < 0.001; 33% versus 11%; P < 0.001, respectively). Multivariate analysis showed large breast volume, FiF-IMRT and chemotherapy were independent factors associated with worse acute toxicity. There was no difference between treatment arms in the incidence of late toxicities. The 5-year recurrence-free survival was 96.3% for both FiF-IMRT and HT-IMRT and the 5-year overall survival was 96.3% for FiF-IMRT and 97.4% for HT-IMRT.

CONCLUSIONS

Our study showed significant reduction in acute skin toxicity using HT-IMRT compared with FiF-IMRT, without significant reduction in late skin toxicities. On the basis of these findings, inverse-planned IMRT could be used in routine practice for whole-breast irradiation with careful plan optimisation to achieve the required dose constraints for organs at risk.

Point-of-care ultrasound at Role 1: is it time for a rethink?

Introduction

The past 20 years have seen a rapid increase in point-of-care ultrasound (POCUS) use in the prehospital sphere. However, in the British Army there is no POCUS capability in the Defence Primary Healthcare (DPHC) or deployed Role 1 setting. POCUS can improve diagnostic capability, influence management decisions and transfer destination, and is a useful triage tool in mass casualty management.

Method

A survey on POCUS use was sent to 279 clinicians working in the Role 1, civilian prehospital and Defence Primary Healthcare environments. Questions explored current levels of experience and training, indications for use and attitudes towards roll out. Results were analysed using a mixed methods approach.

Results

There were 124 respondents (279 recipients; 44.4% response rate). 74.2% (92 respondents) had no experience of using POCUS while 9.7% (12 respondents) were classed as frequent users. The four most common indications for prehospital POCUS were abdominal, cardiac and lung imaging and vascular access. The majority of respondents felt that POCUS would add value in the deployed Role 1 environment; this was even more evident in the frequent user group. Common concerns were difficulty maintaining currency, governance burden and uncertainty over impact on management.

Conclusion

The majority of doctors surveyed feel that POCUS would add value at Role 1 and is a capability that should be developed. The authors will watch with interest the progress of Project MORPHO.

Abstract P4-16-12: Does initial cardiac imaging impact clinical outcomes in patients with breast cancer?

Background: Echocardiography (echo) and multigated acquisition (MUGA) scans are the most commonly used modalities to assess cardiac function during breast cancer (BC) treatment. However, a case series of 176 patients with cancer suggests enhanced cardiac care with echo surveillance. We hypothesized that patients with early BC imaged by echo have improved cardiac outcomes compared to those imaged by MUGA.

Methods: Consecutive patients with stage I to III breast cancer undergoing pre-treatment echo or MUGA were retrospectively screened from January 2010 to December 2014. Patients participating in clinical trials with mandated imaging and/or cardiac reviews were excluded. Demographics, medical history and clinical events were collected via chart review and electronic health records. All patients had a minimum 1 year of follow-up. The primary outcome was a composite of death, cardiac hospitalization or cardiac emergency room visit.

Results: 598 patients were identified as having a baseline echo and 636 had had baseline MUGA. Mean follow-up was 4.5±1.4 years. Patients undergoing MUGA were younger, had more advanced stage of disease and received more anthracycline and trastuzumab (table1). Patients imaged by MUGA had lower cardiac function at baseline compared to echo, LVEF 64% vs. LVEF 65% respectively, P &lt;0.001. Cancer therapy related cardiac dysfunction was similar between groups, 10% vs. 11%, p=0.81. Patients in the echo group were more likely to be seen by cardiology, 7% vs. 3%, p&lt;0.0001, and to be initiated on beta blocker, 4% vs. 1%, p=0.006, or angiotensin converting enzyme inhibitor, 3% vs. 1%, p=0.002.However, there was no difference between groups for the primary outcome, 10% event rate in each group, even after adjustment for age, BC stage, chemotherapy and cardiac medications, hazard ratio 1.04 (CI 0.72-1.49), p=0.842.

Conclusion: For patients with early stage BC, the choice of cardiac imaging modality at baseline does not impact adverse cardiac events. However, patients undergoing echo were more likely to be evaluated and managed by cardiology.

Table 1.Baseline Characteristics Echo (N=598)MUGA (N=636)Age mean54±1053±10*BMI mean29±629±7Cardiovascular HistoryDiabetes66(11%)56(9%)Hypertension154(26%)155(24%)Dyslipidemia83(14%)75(12%)CAD9(2%)6(1%)CHF7(1%)4(1%)Beta Blocker22(4%)28(4%)ACE-Inhibitor51(9%)64(10%)Angiotensin Receptor Blocker69(12%)44(7%)*Cancer HistoryStage*Stage I65(11%)56(9%)Stage II377(63%)361(57%)Stage III155(26%)219(34%)Receptor StatusTriple negative64(11%)76(12%)HER2 negative, hormone positive342(58%)387(61%)HER2 positive192(32%)173(27%)Cancer TherapyChemotherapy (any)528(88%)594(93%)*Anthracycline310(52%)394(62%)*Trastuzumab170(28%)148(23%)*Anthracycline & trastuzumab6(1%)19(3%)*Hormone therapy459(77%)487(77%)Radiation (any)487(81%)527(83%)Radiation left side237(49%)259(49%)Surgery597(100%)633(100%)* p&lt;0.05 for comparison between echo and MUGA groups

Citation Format: Parent S, Xu L, Becher H, Mackey J, King K, Pituskin E, Paterson I. Does initial cardiac imaging impact clinical outcomes in patients with 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 P4-16-12.

Effect of Brönsted acidic ionic liquid 1-(1-propylsulfonic)-3-methylimidazolium chloride on growth and co-fermentation of glucose, xylose and arabinose by Zymomonas mobilis AX101

The potential of large-scale lignocellulosic biomass hydrolysis to fermentable sugars using ionic liquids has increased interest in this green chemistry route to fermentation for fuel-ethanol production. The ionic liquid 1-(1-propylsulfonic)-3-methylimidazolium chloride compared to other reported ionic liquids has the advantage of hydrolysing lignocellulosic biomass to reducing sugars at catalytic concentrations (≤0·032 mol l^-1 ) in a single step. However, effects of this ionic liquid on co-fermentation of glucose, xylose and arabinose to ethanol by recombinant Zymomonas mobilisAX101 has not been studied. Authentic glucose, xylose and arabinose were used to formulate fermentation media at varying catalytic 1-(1-propylsulfonic)-3-methylimidazolium chloride concentrations for batch co-fermentation of the sugars using Z. mobilisAX101. The results showed that at 0·008, 0·016 and 0·032 mol l^-1 ionic liquid in the culture medium, cell growth decreased by 10, 27 and 67% respectively compared to the control. Ethanol yields were 62·6, 61·8, 50·5 and 23·1% for the control, 0·008, 0·016 and 0·032 mol l^-1 ionic liquid respectively. The results indicate that lignocellulosic biomass hydrolysed using 0·008 mol l^-1 of 1-(1-propylsulfonic)-3-methylimidazolium chloride would eliminate an additional separation step and provide a ready to use fermentation substrate.

SIGNIFICANCE AND IMPACT OF STUDY

This is the first reported study of the effect of the Brönsted acidic ionic liquid 1-(1-propylsulfonic)-3-methylimidazolium chloride on growth and co-fermentation of glucose, xylose and arabinose by Zymomonas mobilisAX101 in batch culture. Growth on and co-fermentation of the sugars by Z. mobilisAX 101 with no significant inhibition by the ionic liquid at the same catalytic amounts of 0·008 mol l^-1 used to hydrolyse lignocellulosic biomass to reducing sugars overcome two major hurdles that adversely affect the process economics of large-scale industrial cellulosic fuel ethanol production; the energy-intensive hydrolysis and ionic liquid separation steps.

Abstract P6-13-08: A novel comparative analysis approach to personalize chemotherapy dose in early breast cancer

Background: Worldwide, body surface area [BSA] is used to calculate chemotherapy dose. The BSA formula was originally developed in 1916, derived from height and weight, with no consideration of other patient characteristics. Most chemotherapy agents have a narrow therapeutic index and are distributed in lean body mass [LBM], leading to under- or over-dosing and deleterious effects to major organs when body composition is not considered. To date, while experts worldwide acknowledge the limitations and risks of BSA dosing, no practical approach to personalizing chemotherapy dose has been developed. Ideally, body composition would be assessed by tests already routinely performed, avoiding unnecessary radiation exposure, clinic visits, discomfort to the patient, and cost. The majority of patients undergo cardiac imaging prior to chemotherapy. We hypothesized that clinical parameters routinely performed prior to chemotherapy could predict LBM in early breast cancer patients.

Method: Early stage breast cancer patients (n = 45) enrolled in the Multidisciplinary Team Intervention in Cardio-Oncology (TITAN) study underwent pre-treatment cardiac MRI, body composition (iDEXA) and laboratory (complete blood cell count and chemistry). Cardiac MRI and iDEXA are considered 'gold standard' imaging modalities, the accuracy of which allow for significantly reduced sample size.

Our modeling approach, which is novel in this area, aimed to select the best combination of parameters with the most predictive ability of total lean mass (iDEXA). The parameters included in study are: cardiac MRI metrics (LV mass, cardiac output), and laboratory parameters associated with major organ function (albumin, creatinine, bilirubin). All parameters were tested using univariate, multivariate and subset selection approach. Akaike's Information Criterion (AIC) was used to measure model quality, with lower AIC values indicating closer prediction.

Results: The univariate analysis of each parameter independently showed LV mass is most predictive with AIC 857.8, while combination of all parameter in multivariate fashion show improvement in prediction with AIC 851. The subset selection approach shows, Adjusted R2 with 4 parameters had AIC 849.14, Schwartz's information criterion (BIC) with 2 parameters had AIC 849.66 and Mallows' C Selection (Cp) model with 3 parameters had the least AIC 848.71 value (P &lt; 0.001).

Conclusion: Our comparative analysis showed that the Cp model with 3 parameters (LV mass, cardiac output and bilirubin) has high prediction ability of LBM. This model will form the basis of a personalized formula for chemotherapy dose calculation. We expect this work to result in optimal cancer-specific outcomes while reducing short and long-term toxicities associated with necessary chemotherapy.

Citation Format: Perri MD, Singhal S, Hegadoren K, Norris C, Mackey J, Paterson I, Pituskin E. A novel comparative analysis approach to personalize chemotherapy dose in early breast cancer [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 P6-13-08.

Age, Sex, and Racial Differences in Neuroimaging Use in Acute Stroke: A Population-Based Study

BACKGROUND AND PURPOSE

Limited information is available regarding differences in neuroimaging use for acute stroke work-up. Our objective was to assess whether race, sex, or age differences exist in neuroimaging use and whether these differences depend on the care center type in a population-based study.

MATERIALS AND METHODS

Patients with stroke (ischemic and hemorrhagic) and transient ischemic attack were identified in a metropolitan, biracial population using the Greater Cincinnati/Northern Kentucky Stroke Study in 2005 and 2010. Multivariable regression was used to determine the odds of advanced imaging use (CT angiography/MR imaging/MR angiography) for race, sex, and age.

RESULTS

In 2005 and 2010, there were 3471 and 3431 stroke/TIA events, respectively. If one adjusted for covariates, the odds of advanced imaging were higher for younger (55 years or younger) compared with older patients, blacks compared with whites, and patients presenting to an academic center and those seen by a stroke team or neurologist. The observed association between race and advanced imaging depended on age; in the older age group, blacks had higher odds of advanced imaging compared with whites (odds ratio, 1.34; 95% CI, 1.12-1.61; P < .01), and in the younger group, the association between race and advanced imaging was not statistically significant. Age by race interaction persisted in the academic center subgroup (P < .01), but not in the nonacademic center subgroup (P = .58). No significant association was found between sex and advanced imaging.

CONCLUSIONS

Within a large, biracial stroke/TIA population, there is variation in the use of advanced neuroimaging by age and race, depending on the care center type.

Final efficacy and updated safety results of the randomized phase III BEATRICE trial evaluating adjuvant bevacizumab-containing therapy in triple-negative early breast cancer

Background

The purpose of this analysis was to assess the long-term impact of adding bevacizumab to adjuvant chemotherapy for early triple-negative breast cancer (TNBC).

Methods

Patients eligible for the open-label randomized phase III BEATRICE trial had centrally confirmed triple-negative operable primary invasive breast cancer (pT1a-pT3). Investigators selected anthracycline- and/or taxane-based chemotherapy for each patient. After definitive surgery, patients were randomized 1:1 to receive ≥4 cycles of chemotherapy alone or with 1 year of bevacizumab (5 mg/kg/week equivalent). Stratification factors were nodal status, selected chemotherapy, hormone receptor status, and type of surgery. The primary end point was invasive disease-free survival (IDFS; previously reported). Secondary outcome measures included overall survival (OS) and safety.

Results

After 56 months' median follow-up, 293 of 2591 randomized patients had died. There was no statistically significant difference in OS between treatment arms in either the total population (hazard ratio 0.93, 95% confidence interval [CI] 0.74-1.17; P = 0.52) or pre-specified subgroups. The 5-year OS rate was 88% (95% CI 86-90%) in both treatment arms. Updated IDFS results were consistent with the primary IDFS analysis. Five-year IDFS rates were 77% (95% CI 75-79%) with chemotherapy alone versus 80% (95% CI 77-82%) with bevacizumab. From 18 months after first study dose to study end, new grade ≥3 adverse events occurred in 4.6% and 4.5% of patients in the two arms, respectively.

Conclusion

Final OS results showed no significant benefit from bevacizumab therapy for early TNBC. Late-onset toxicities were rare in both groups. Five-year OS and IDFS rates suggest that the prognosis for patients with TNBC is better than previously thought.

ClinicalTrials.gov

NCT00528567.

The Adrenocortical Response to Synthetic ACTH Following a Trek to High Altitude

Gradual ascent to high altitude is typically associated with reduced resting aldosterone and unchanged cortisol, features that may facilitate acclimatization but are poorly understood. The aim of the study was to investigate the cortisol and aldosterone response to adrenocorticotrophic hormone at altitude. Eleven subjects underwent a 250 μg short synacthen test at sea-level and again after trekking to 3 600 m in Nepal. Cortisol and aldosterone were measured by conventional assay from blood samples taken immediately prior to the administration of synacthen (T0) and then 30 (T30) and 60 (T60) min later. At 3 600 m resting basal cortisol and aldosterone levels were both significantly lower than they were at sea-level (p=0.004, p=0.003, respectively). Cortisol values at T30 and T60 were not different between sea-level and 3 600 m but the increment after synacthen was significantly greater (p=0.041) at 3 600 m due to a lower basal value. Aldosterone at T30 and T60 was significantly lower (p=0.003 for both) at 3 600 m than at sea-level and the increment following synacthen was also significantly less (p=0.003) at 3 600 m. At 3 600 m there appears to be a divergent adrenal response to synthetic adrenocorticotrophic hormone with an intact cortisol response but a reduced aldosterone response, relative to sea-level. This may reflect a specific effect of hypoxia on aldosterone synthesis and may be beneficial to acclimatization.

Abstract S1-01: Analysis of molecular prognostic factors associated with tumor immune and stromal microenvironment in BEATRICE, an open-label phase 3 trial in early triple-negative breast cancer (eTNBC)

Background: TNBC is a mutationally complex heterogeneous breast cancer subtype. In BEATRICE, adding bevacizumab to standard adjuvant chemotherapy for eTNBC improved neither invasive disease-free survival (IDFS; primary endpoint) nor overall survival (OS) [Cameron 2013; Bell SABCS 2014]. We explored prognostic effects of tumor-associated immune and stromal gene signatures.

Methods: Gene expression (RNA) was assessed in pretreatment archival tumor tissue using an 800-gene nanostring platform. Given the low event rates and lack of bevacizumab effect in BEATRICE, treatment arms were pooled. The biomarker-evaluable population (BEP; all patients with an evaluable biomarker sample and ≥1 postbaseline efficacy assessment) was dichotomized using median gene expression level as the cutoff. Prognostic associations between IDFS/OS and prespecified candidate gene sets/de novo identified clusters were assessed using univariate Cox proportional hazards models.

Results: Baseline characteristics and efficacy were similar in the BEP (988/2591 randomized pts; 38%) and the overall study population. In hierarchical cluster analysis based exclusively on immune gene expression, immune genes were enriched in 33% of samples, intermediate in 38%, and weak in 28%. Further characterization suggested differential prognostic value of distinct immune and stromal cell gene sets (Table). A significant prognostic effect for IDFS and OS was seen for CD8 effector T cell (Teff) and regulatory T cell (Treg) gene signatures, but not for the Teff:Treg ratio. A less pronounced positive prognostic effect was seen for other gene sets representing immune cells, including macrophages, CD4 T cells, and B cells (data not shown). Activated T helper (Th)-1 cell-derived chemokines and negative immune modulators of T cell activity (eg PD-L1) were highly prognostic for IDFS and OS. Both the cytokine IL-8 and ESM1 (target of VEGF-A pathway activation) were associated with worse IDFS and OS. No association was seen between outcome and markers for classic microvasculature (CD31, CD34), cancer-associated fibroblasts (FAP, BGN, DCN), VEGF-A, or VEGF-C.

 IDFSOSGene signatureHR (95% CI)Interaction p-valueHR (95% CI)Interaction p-valueTeff0.40 (0.28-0.57)7.2x10-70.29 (0.17-0.49)4.2x10-6Treg0.38 (0.26-0.54)1.6x10-70.23 (0.13-0.40)2.9x10-7Teff:Treg ratio0.80 (0.58-1.12)0.20.89 (0.57-1.39)0.6Th10.45 (0.31-0.64)8.1x10-60.43 (0.27-0.70)5.8x10-4PD-L10.42 (0.29-0.60)1.8x10-60.24 (0.14-0.41)3.4x10-7IL-81.48 (1.06-2.08)0.0221.89 (1.18-3.01)0.0076ESM11.73 (1.23-2.43)0.00172.22 (1.38-3.58)0.001

Conclusions: These molecular gene signature analyses in eTNBC confirm that markers of cytotoxic CD8 T cells are associated with good prognosis. This is the first report of a positive prognostic effect of regulatory T cell markers, immune checkpoint modulators, and macrophage-associated markers in the adjuvant TNBC setting. High VEGF-A activity, but not its expression, was associated with worse prognosis. The strong prognostic effect of immune checkpoint modulators suggests equilibrium between cytotoxic T cells and their inhibitors in eTNBC, supporting further exploration of immune checkpoint inhibitors in this therapeutic context.

Citation Format: Molinero L, Yu J, Li C, Deurloo R, Dent RA, Bell R, Brown J, Parmar M, Toi M, Suter T, Steger G, Pivot X, Mackey J, Jackisch C, Hall P, Hegde P, Bais C, Cameron D. Analysis of molecular prognostic factors associated with tumor immune and stromal microenvironment in BEATRICE, an open-label phase 3 trial in early triple-negative breast cancer (eTNBC). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S1-01.

YouTube™ as a source of patient information about knee replacement surgery

Empowering patients or providing potentially dangerous information?

Lessons learned while undertaking high altitude medical research in the Himalayas

Undertaking medical research during military adventurous training expeditions presents a unique set of challenges to medical personnel, and for those considering doing so in the future the task may seem daunting. This article details some of the challenges faced whilst undertaking high altitude research on a recent Defence Medical Services (DMS) adventurous training expedition to the Dhaulagiri circuit in Nepal. By discussing what led to some of the problems encountered, how they were overcome, and in some instances how they could have been avoided in the first place, it is hoped that the article will act as a guide for others who plan on undertaking future research in a similar environment.

Abstract P3-06-34: Plasma (p) VEGF-A and VEGFR-2 biomarker (BM) results from the BEATRICE phase III trial of bevacizumab (BEV) in triple-negative early breast cancer (BC)

Background: Several candidate BMs have been explored in randomized trials of BEV across tumor types with the aim of identifying patients (pts) deriving the most substantial benefit from BEV therapy. In phase III trials, baseline pVEGF-A and pVEGFR-2 showed potential predictive value in metastatic BC (AVADO, AVEREL), pancreatic cancer (AViTA), and gastric cancer (AVAGAST; VEGF-A only). The randomized phase III BEATRICE trial, evaluating the addition of BEV to adjuvant chemotherapy in pts with triple-negative early BC, includes a comprehensive program to identify potential BMs predicting efficacy and toxicity of BEV therapy. We report results for baseline pVEGF-A and pVEGFR-2.

Methods: After selection of chemotherapy (anthracycline and/or taxane), pts with T1a-T3 operable BC were randomized 1:1 to receive ≥4 cycles of chemotherapy either alone or with 1 year of BEV 5 mg/kg/wk equivalent. The primary endpoint is invasive disease-free survival (IDFS). pEDTA samples were collected from consenting pts at baseline (before treatment, after surgery), during study treatment, and at relapse. Pts were dichotomized using the median baseline concentration of each marker as the cut-off between high and low cohorts; further exploratory analyses were also performed by quartile.

Results: Between Dec 2007 and Mar 2010, 2591 pts were enrolled. Of these, 1273 (49%) consented to the BM study and 1178 (45%) were included in the BM-evaluable population (BEP). Overall, the BEP was representative of the ITT population except for lower proportions of Asian pts (12% vs 24%). IDFS was similar in the BEP and ITT populations. Baseline characteristics were balanced between arms in the BEP. Baseline pVEGF-A showed neither prognostic nor predictive value using the median as the cut-off, although with a third quartile (Q3) cut-off there was a more pronounced but non-significant differentiation between treatments (HR 0.92 [low] vs 0.64 [high]). High baseline pVEGFR-2 showed potential predictive value for BEV efficacy (HR 1.24 [low] vs 0.61 [high]; p=0.029).

The role of neoadjuvant (HER)2-targeted therapies in (HER)2-overexpressing breast cancers

Women receiving neoadjuvant systemic therapy for primary operable or inoperable breast cancer can potentially benefit in a number of ways, but the main advantage, which has been consistently demonstrated, is improved tumour resectability. Given the improvement in outcomes with the adjuvant use of trastuzumab in patients with early-stage breast cancer positive for the human epidermal growth factor receptor 2 (her2), questions have been raised about the use of trastuzumab in the neoadjuvant setting. The present paper reviews the currently available data and outlines suggestions from a panel of Canadian oncologists about the use of trastuzumab and other her2-targeted agents in the neoadjuvant setting.

The panel focussed on

the use of trastuzumab and other her2-targeted agents as neoadjuvant therapy in primary operable, locally advanced, and inflammatory breast cancer; and

possible choices of chemotherapeutic regimens with trastuzumab.

The suggestions described here will continue to evolve as data from current and future trials with trastuzumab and other her2-targeted agents emerge.

Optimizing the management of HER2-positive early breast cancer: the clinical reality

Breast cancer positive for HER2 (human epidermal growth factor receptor 2) is associated with a poor prognosis for patients with both early-stage and metastatic breast cancer. Trastuzumab has been shown to be effective and is now considered the standard of care for early-stage patients with HER2-positive breast cancer. In that population, trastuzumab has been studied in six randomized clinical trials. Overall, use of this agent leads to a significant reduction in risk of disease recurrence and improvement in overall survival. Despite the strong evidence for the use of trastuzumab in managing HER2-positive early breast cancer (EBC), a number of clinical controversies remain. The authors of this paper undertook a review of the available scientific literature on adjuvant trastuzumab to produce practical considerations from Canadian oncologists. The panel focused their discussion on five key areas: Management of node-negative disease with tumours 1 cm or smaller in size. Management of HER2-positive EBC across the spectrum of the disease (that is, nodal and steroid hormone receptor status, tumour size) Timing of trastuzumab therapy with chemotherapy for early-stage disease: concurrent or sequential. Treatment duration of trastuzumab for EBC. The role of non-anthracycline trastuzumab-based regimens.

Population-based study of wake-up strokes

OBJECTIVE

Previous studies have estimated that wake-up strokes comprise 8%to 28% of all ischemic strokes, but these studies were either small or not population-based. We sought to establish the proportion and event rate of wake-up strokes in a large population-based study and to compare patients who awoke with stroke symptoms with those who were awake at time of onset.

METHODS

First-time and recurrent ischemic strokes among residents of the Greater Cincinnati/Northern Kentucky region (population 1.3 million) in 2005 were identified using International Classification of Diseases-9 codes 430-436 and verified via study physician review. Ischemic strokes in patients aged 18 years and older presenting to an emergency department were included. Baseline characteristics were ascertained, along with discharge modified Rankin Scale scores and 90-day mortality.

RESULTS

We identified 1,854 ischemic strokes presenting to an emergency department, of which 273 (14.3%) were wake-up strokes. There were no differences between wake-up strokes and all other strokes with regard to clinical features or outcomes except for minor differences in age and baseline retrospective NIH Stroke Scale score. The adjusted wake-up stroke event rate was 26.0/100,000. Of the wake-up strokes, at least 98 (35.9%) would have been eligible for thrombolysis if arrival time were not a factor.

CONCLUSIONS

Within our population, approximately 14% of ischemic strokes presenting to an emergency department were wake-up strokes. Wake-up strokes cannot be distinguished from other strokes by clinical features or outcome. We estimate that approximately 58,000 patients with wake-up strokes presented to an emergency department in the United States in 2005.

Canadian Initiatives for Locally Advanced Breast Cancer Research and Treatment: Inaugural Meeting of the Canadian Consortium for LABC

The inaugural Canadian Consortium for LABC (locally advanced breast cancer) conference was held at Langdon Hall, Cambridge, Ontario, April 11–12, 2010. The meeting focused on current and future directions in labc treatment and research, the specific benefits of labc as a model for clinical and translational research, strategies for increased national and international collaboration, and ongoing clinical trials. Exciting Canadian initiatives in labc research are underway, focusing on identifying molecular signatures that will allow for the development of new tailored therapies. The challenge of identifying patient subgroups for accrual is being addressed through strategies to foster and improve national collaboration. This meeting report includes highlights from each presentation at the conference.

The role of HER2-targeted therapies in women with HER2-overexpressing metastatic breast cancer

The role of targeted therapies in the treatment of women with breast cancer has been rapidly evolving. Trastuzumab, a monoclonal antibody against the human epidermal growth factor receptor 2 (HER2), was the first HER2-targeted therapy that clearly demonstrated a significant clinical benefit for women with HER2-overexpressing metastatic breast cancer (mbc). However, in recent years it has become increasingly apparent that, when trastuzumab is used in the first-line setting in combination with chemotherapy, most women eventually develop progressive disease. Determining the treatment options available to women who have progressed while on trastuzumab therapy has been hampered by a paucity of high-quality published data. In addition, with the standard use of trastuzumab in the adjuvant setting (for eligible HER2-positive patients), the role of anti-HER2 agents for patients who experience a breast cancer relapse has become a clinically relevant question. This manuscript reviews current available data and outlines suggestions from a panel of Canadian oncologists about the use of trastuzumab and other HER2-targeted agents in two key mbc indications:Treatment for women with HER2-positive mbc progressing on trastuzumab (that is, treatment beyond progression)Treatment for women with HER2-positive mbc recurring following adjuvant trastuzumab (that is, re-treatment)The suggestions set out here will continue to evolve as data and future trials with trastuzumab and other HER2-targeted agents emerge.

BCIRG 007: Serum HER2 levels in women with metastatic HER2-amplified breast cancer

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Background: BCIRG 007 is a multicenter, phase 3 randomized trial comparing docetaxel and trastuzumab (TH) with docetaxel, platinum salt (cisplatin or carboplatin) and trastuzumab (TCH) as first line chemotherapy in women with metastatic breast cancer (MBC). Women enrolled in the study had to have primary breast tumors with HER2 amplification as determined by centralized FISH analysis. Methods: We determined the percentage of subjects with HER2 amplification who had elevated (>15ng/mL) baseline levels of serum HER2 prior to the initiation of trastuzumab-based therapies. Baseline was considered to be the last available determination within 21 days prior to first treatment. Results: The median baseline serum HER2 levels was 75.8 ng/mL (range=8–3,280 ng/mL) for all subjects (n=123), with no statistical difference between subjects randomized to receive TH (median=65.9 ng/mL, n=64) and those randomized to receive TCH (median=89.9 ng/mL, n=59). Overall, 89% of the 123 subjects with HER2-amplified primary tumors had serum HER2 levels >15 ng/mL at the time of metastatic disease (86% in TH vs 92% in TCH). Conclusions: There was no statistical impact of baseline serum HER2 levels on any important clinical event: response to treatment, clinical benefit (response or stable disease for more than 24 weeks), disease progression or death. Conversely, when serum HER2 was measured over time, subjects with higher levels had an elevated risk of experiencing progressive disease (p=.003), even after adjustment for extent of disease (1 or 2 vs 3 or more organs involved) and presence of visceral disease. These analyses suggest that monitoring serum HER2 levels over the course of disease may be a means for detecting progressive disease in women with HER2 amplified breast cancer. Given the long intervals between the serum HER2 measurement and progression (up to 9 months), caution is required in interpreting these results.

No significant financial relationships to disclose.

Class III beta tubulin expression and benefit from adjuvant cisplatin/vinorelbine chemotherapy in operable non-small cell lung cancer: Analysis of the National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) study JBR.10

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Background: Biomarkers may be useful to select patients who will benefit from a particular chemotherapy regimen. High class III beta tubulin (bTubIII) expression in advanced NSCLC is known to correlate with reduced response rates and inferior survival with the anti-microtubule agents vinorelbine or paclitaxel. JBR.10 demonstrated a 12% and 15% improvement in 5-year recurrence-free (RFS) and overall survival (OS) respectively with the addition of cisplatin and vinorelbine following resection of stage IB-II NSCLC. We sought to determine the impact of bTubIII on patient outcome and benefit from adjuvant chemotherapy in the JBR.10 trial. Methods: We performed an immunohistochemical assay for bTubIII on primary tumor tissue available from 265 of the 482 patients in JBR.10. A validated, numerical bTubIII score was assigned by two observers based on the intensity and frequency of tumour cell staining. Tumours were classified as bTubIII “low” or “high” based on the median score. We examined the prognostic impact of bTubIII in patients treated with or without chemotherapy, and the survival benefit from chemotherapy in low versus high bTubIII subgroups. Results: High bTubIII expression was associated with poorer RFS (HR = 1.9, p = 0.01) in patients treated with surgery alone, but not in patients treated with adjuvant chemotherapy (HR = 1.1, p = .75). In the low bTubIII subgroup, the improvement in RFS with chemotherapy was non-significant (HR = 0.78, p = 0.4), while the improvement in RFS with chemotherapy was significant in the high bTubIII subgroup (HR = 0.45, p = 0.002). With Cox regression, the interaction between bTubIII status and chemotherapy treatment in predicting RFS did not reach statistical significance (p = 0.15). Results for OS were similar. Conclusions: Chemotherapy appeared to overcome the negative prognostic impact of high bTubIII expression. Greater benefit from adjuvant chemotherapy was seen in patients with high bTubIII expression. This is contrary to what has been seen in the setting of advanced disease; possible reasons for this difference are being explored.

No significant financial relationships to disclose.

High expression of nucleoside transporter hENT1 predicts a worse event-free survival in relapsed/refractory Hodgkin lymphoma patients treated with gemcitabine, vinorelbine, and liposomal doxorubicin—A CALGB 59804 correlative study

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Background: CALGB 59804 was a phase I/II trial of gemcitabine, vinorelbine, and liposomal doxorubicin (GVD) for pts with relapsed Hodgkin lymphoma (HL). Overall response rate (RR) was 70% (manuscript in review). Plasma membrane nucleoside transporters such as hENT1 are important in transporting nucleoside analogs into cells to exert their pharmacologic effects. We hypothesized high hENT1 expression would predict better RR and outcome in pts treated with GVD. Methods: 58 of 91 pts enrolled in CALGB 59804 had sufficient tissue for study; 31 relapse biopsies and 27 initial diagnosis biopsies. Expression of hENT1 was evaluated by immunohistochemistry in formalin fixed tissue and scored independently by two hematopathologists (RL and EH) blinded to the clinical outcomes. Positivity for hENT1 was defined as >25% of Reed-Sternberg (RS) cells expressing hENT1. Expression was correlated with clinical factors, including IPS at relapse, as well as the overall (OS) and event-free survival (EFS). Results: Expression of hENT1 in RS cells was heterogeneous among cases. 28/58 cases (48%) were hENT1-positive. hENT1-expression was not associated with age, gender, stage, IPS (≤2 or >2), or maximum toxicity grade (≤2 or >2). Compared to hENT1-negative pts, hENT1-positive pts were less likely to have complete or partial response (19/30, 63% versus 22/28, 76%, P=0.20, chi square). hENT1 expression was not significantly associated with OS (P=0.18). Univariate log-rank analysis showed hENT1 positivity and IPS >2 correlated significantly with a lower EFS (P=0.05, and P=0.03, respectively). Multivariate Cox regression analysis confirmed that IPS >2 and hENT1 positivity were independent predictors of EFS (Hazard ratio 2.16, 95%CI 1.08–4.35, P=0.03; and Hazard ratio 2.10, 95% CI 1.06–4.19, P=0.03, respectively). P-values are two-sided. Conclusions: Contrary to our hypothesis, there is an inverse relationship between EFS and hENT1 expression in relapsed HL pts treated with GVD. High expression of hENT1 did not identify gemcitabine-sensitive disease, but may identify a biologically aggressive and/or treatment refractory subtype of HL.

No significant financial relationships to disclose.

Prognostic significance of HER-2/neu over-expression on the incidence of brain metastasis in newly diagnosed breast cancer

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Background: As systemic therapy improves, brain metastases (BM) from breast cancer are becoming increasingly evident. An increased risk of BM in HER-2/neu over-expressing metastatic breast cancer patients has been suggested. However, the relationship between HER-2/neu over-expression and the risk of BM in newly diagnosed breast cancer patients is unknown. Methods: To determine incidence of BM in HER-2/neu over-expressing breast cancer patients, a cohort of patients between 01/1998 and 12/2003 with uniform HER-2/neu testing were identified from a cancer registry. A total of 460 patients with HER-2/neu over-expression and 500 patients with HER-2/neu negative disease were reviewed. Patients were excluded if there was breast cancer diagnosed before 01/1998 or others cancer. A total of 301 HER-2/neu over-expressing and 363 HER-2/neu negative patients were included for this analysis. The association between histological features and the occurrence of BM were evaluated with univariate and multivariate analyses. Results: BM were identified in 8% (24 patients) of HER-2/neu over-expressing breast cancer patients compared to only 1.7% (6 patients) in the HER-2/neu negative patients (hazard ratio 5.15 [2.079–12.78], p=0.0001). In patients with recurrent disease, the proportion of BM for HER-2/neu over-expressing patients was 24% compared to 10% in HER-2/neu negative patients. HER-2/neu over-expression, tumor size >2cm, ≥ 4 nodes positive and grade 2/3 were predictors of BM in univariate analysis. In multivariate analysis, HER-2/neu over-expression and tumor size>2cm were an independent prognostic factors for the development of BM, while hormone receptors expressions was protective (p=0.02). Conclusions: Our population based study show that newly diagnosed HER-2/neu over-expressing breast cancer patients are at significantly increased risk for BM. As most BM occur in HER-2/neu over-expressing patients with systemic metastatic disease, these findings could prompt consideration of brain prophylaxis strategies and/or serial radiologic screening to detect asymptomatic BM.

No significant financial relationships to disclose.

ER+ PR- breast cancer defines a unique subtype of breast cancer that is driven by growth factor signaling and may be more likely to respond to EGFR targeted therapies

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Background: Hormonal based therapy has long been the mainstay for treatment of ER+ breast cancer. ER+ PR- disease is now known to exhibit different clinical behavior compared to ER+PR+ disease. Recent data indicate that ER+PR- disease is characterized by a lower response rate to estrogen deprivation, has a worse prognosis compared to ER+ PR+ disease, and may be dependent on other signaling pathways. To evaluate the role of the EGFR tyrosine kinase inhibitor gefitnib in the treatment of breast cancer, we conducted a pre-surgical study in women with operable disease. Methods: Frozen core biopsies were obtained at baseline. Patients then received a short-term exposure to gefitinib (at least 2 weeks) prior to definitive surgery when a frozen tumor specimen was obtained. Tissue integrity and composition was verified by H and E and RNA was isolated for microarray analysis. 59 women were enrolled in the study of which 43 were evaluable for molecular analysis. Baseline microarrays were performed on the initial biopsies to classify the ‘subtype‘ of breast cancer (e.g. basal, luminal, HER2 amplified). To analyze the genetic changes that occur in breast cancer tissue with exposure to gefitinib, a direct comparison of the baseline sample and post-treatment tumor was performed. In addition, ER and PR status were determined by immunohistochemistry and compared to the microarray findings. Changes in Ki67 and a set of cell cycle genes were used to define ‘molecular response” to gefitinib. Of the 43 samples evaluated by microarray, 11 patients were categorized as exhibiting molecular growth inhibition, 10 patients as molecular growth proliferation, and 22 did not have a significant change in Ki67 and the cell cycle gene set to assign a response. When grouped by subtype, ER+PR- and HER2 amplified tumors define a subgroup more likely to show molecular growth inhibition with gefitinib. Conversely, ER+PR+ tumors were more likely to show molecular growth proliferation. Conclusions: These results support the hypothesis that ER+PR- breast cancer is growth factor dependent and constitutes a unique subgroup of ER+ patients which may be more likely to benefit from EGFR inhibition.

[Table: see text]

High-dose mitoxantrone–vinblastine–cyclophosphamide and autologous stem cell transplantation for stage III breast cancer: final results of a prospective multicentre study

BACKGROUND

Stage III breast cancer patients continue to suffer high relapse and death rates despite standard chemotherapy regimens. High-dose alkylator chemotherapy does not further improve outcome. This phase II study evaluated a novel high-dose chemotherapy regimen which combined active breast cancer agents with differing mechanisms of action.

PATIENTS AND METHODS

Eligibility included at least seven involved axillary nodes (AxLNs) for tumours <5 cm, at least four AxLNs for tumours >5 cm or locally advanced breast cancer (LABC). Patients received four cycles of fluorouracil-adriamycin-cyclophosphamide (FAC) followed by one cycle of mitoxantrone 63 mg/m(2)-vinblastine 12.5 mg/m(2)-cyclophosphamide 6 g/m(2) (MVC) with autologous blood stem cell transplantation (ASCT).

RESULTS

Between April 1995 and December 1998, 92 patients aged 21-65 years (median 45 years) were enrolled, of whom 25 were treated preoperatively for LABC and 67 were treated postoperatively. Although there was no early treatment-related mortality, one late death occurred from secondary acute myeloid leukaemia. The 7-year event-free and overall survival rates were 53% (95% confidence interval 42-64%) and 62% (95% CI 52-73%), respectively, with no significant difference between pre- and postoperative groups.

CONCLUSION

FAC followed by MVC-ASCT is feasible and reasonably well tolerated, but does not result in improved survival rates compared with other conventional or high-dose regimens for stage III breast cancer.

Whole genomewide linkage screen for neural tube defects reveals regions of interest on chromosomes 7 and 10

Neural tube defects (NTDs) are the second most common birth defects (1 in 1000 live births) in the world. Periconceptional maternal folate supplementation reduces NTD risk by 50-70%; however, studies of folate related and other developmental genes in humans have failed to definitively identify a major causal gene for NTD. The aetiology of NTDs remains unknown and both genetic and environmental factors are implicated. We present findings from a microsatellite based screen of 44 multiplex pedigrees ascertained through the NTD Collaborative Group. For the linkage analysis, we defined our phenotype narrowly by considering individuals with a lumbosacral level myelomeningocele as affected, then we expanded the phenotype to include all types of NTDs. Two point parametric analyses were performed using VITESSE and HOMOG. Multipoint parametric and nonparametric analyses were performed using ALLEGRO. Initial results identified chromosomes 7 and 10, both with maximum parametric multipoint lod scores (Mlod) >2.0. Chromosome 7 produced the highest score in the 24 cM interval between D7S3056 and D7S3051 (parametric Mlod 2.45; nonparametric Mlod 1.89). Further investigation demonstrated that results on chromosome 7 were being primarily driven by a single large pedigree (parametric Mlod 2.40). When this family was removed from analysis, chromosome 10 was the most interesting region, with a peak Mlod of 2.25 at D10S1731. Based on mouse human synteny, two candidate genes (Meox2, Twist1) were identified on chromosome 7. A review of public databases revealed three biologically plausible candidates (FGFR2, GFRA1, Pax2) on chromosome 10. The results from this screen provide valuable positional data for prioritisation of candidate gene assessment in future studies of NTDs.

Dose rate calculations for a reconnaissance vehicle

A Chemical Nuclear Reconnaissance System (CNRS) has been developed by the British Ministry of Defence to make chemical and radiation measurements on contaminated terrain using appropriate sensors and recording equipment installed in a land rover. A research programme is under way to develop and validate a predictive capability to calculate the build-up of contamination on the vehicle, radiation detector performance and dose rates to the occupants of the vehicle. This paper describes the geometric model of the vehicle and the methodology used for calculations of detector response. Calculated dose rates obtained using the MCBEND Monte Carlo radiation transport computer code in adjoint mode are presented. These address the transient response of the detectors as the vehicle passes through a contaminated area. Calculated dose rates were found to agree with the measured data to be within the experimental uncertainties, thus giving confidence in the shielding model of the vehicle and its application to other scenarios.

Darbepoetin alfa administered every 3 weeks alleviates anaemia in patients with solid tumours receiving chemotherapy; results of a double-blind, placebo-controlled, randomised study

This dose-finding, placebo-controlled study evaluated the safety and efficacy of darbepoetin alfa administered every 3 weeks (Q3W) to anaemic patients receiving chemotherapy. In part A, patients (haemoglobin </=110 g/l) were randomised in a 1:4 ratio to receive 1 of 6 doses of darbepoetin alfa (4.5, 6.75, 9.0, 12.0, 13.5 and 15.0 microg/kg) or placebo Q3W for 12 weeks. In part B, patients received open-label darbepoetin alfa. Patients (n=249) were evaluated for safety, haemoglobin endpoints and red blood cell (RBC) transfusions. Darbepoetin alfa given at doses ranging from 4.5 to 15.0 microg/kg Q3W was well tolerated and comparable to placebo in terms of safety. No neutralising antibodies were detected. All doses (from 4.5 to 15 microg/kg) reduced transfusions compared with placebo, and resulted in >50% of patients achieving a haematopoietic response. Administration of darbepoetin alfa Q3W has a tolerable safety profile and effectively ameliorates anaemia due to chemotherapy.

Plasma and neutrophil fatty acid composition in advanced cancer patients and response to fish oil supplementation

Metabolic demand and altered supply of essential nutrients is poorly characterised in patients with advanced cancer. A possible imbalance or deficiency of essential fatty acids is suggested by reported beneficial effects of fish oil supplementation. To assess fatty acid status (composition of plasma and neutrophil phospholipids) in advanced cancer patients before and after 14 days of supplementation (12+/-1 g day(-1)) with fish (eicosapentaenoic acid, and docosahexaenoic acid) or placebo (olive) oil. Blood was drawn from cancer patients experiencing weight loss of >5% body weight (n=23). Fatty acid composition of plasma phospholipids and the major phospholipid classes of isolated neutrophils were determined using gas liquid chromatography. At baseline, patients with advanced cancer exhibited low levels (<30% of normal values) of plasma phospholipids and constituent fatty acids and elevated 20 : 4 n-6 content in neutrophil phospholipids. High n-6/n-3 fatty acid ratios in neutrophil and plasma phospholipids were inversely related to body mass index. Fish oil supplementation raised eicosapentaenoic acid and docosahexaenoic acid content in plasma but not neutrophil phospholipids. 20 : 4 n-6 content was reduced in neutrophil PI following supplementation with fish oil. Change in body weight during the supplementation period related directly to increases in eicosapentaenoic acid in plasma. Advanced cancer patients have alterations in lipid metabolism potentially due to nutritional status and/or chemotherapy. Potential obstacles in fatty acid utilisation must be addressed in future trials aiming to improve outcomes using nutritional intervention with fish oils.

Selective cytotoxicity of gemcitabine in bladder cancer cell lines

We have examined the cytotoxic effect of gemcitabine in intravesical therapy using an in vitro co-cultured spheroid model composed of transitional cell carcinoma (TCC) and fibroblasts from both human and rat species. Immunohistochemistry analysis of the co-cultured spheroids, using cytokeratin-13 and vimentin antibodies against TCC and fibroblasts, respectively, showed the central location of fibroblasts within the spheroid, whereas TCC formed the peripheral layers. Spheroids composed of human TCC and fibroblasts (MGH-U3/CRL-1120 or RT-112/CRL-1120) as well as rat TCC and their corresponding fibroblasts (AY-27/RF-Ed1) displayed the same drug tolerance profile after an exposure of 0, 1, 3, 5, 7 and 14 days. As confirmed by time-lapse photography, MTT essay and vital dye staining, gemcitabine selectively killed the human and rat bladder cancer cell lines, but did not affect un-transformed human and rat fibroblast lines.

Resistance to Scald (Rhynchosporium secalis) in Barley (Hordeum vulgare) Studied by Near-Isogenic Lines: I. Markers and Differential Isolates

ABSTRACT Near-isogenic lines (NILs) with resistance for scald in seventh generation backcross with 'Ingrid' as recurrent parent (RP) were tested with seven differential isolates of Rhynchosporium secalis in Norway and Canada. NILs of 'Turk', 'Brier', 'CI 8162', 'La Mesita', 'Hispont', 'Atlas 46', 'Modoc', 'Hudson', 'Abyssinian', 'Steudelli', and 'CI 2222' also were evaluated for field reactions. The genetic characterization of the NILs (degree of isogeneity with Ingrid) and with each other was carried out. The molecular marker pattern shows that the backcrossing program has resulted in from 86.3 to 100% RP genome in the NILs, depending on the marker system. On an average, 96% RP genome was found in the NILs. There were certain consistent (pairwise) differences between the NILs and RP on chromosomes 3H and 7H. Both chromosomes are known to contain loci conferring resistance to R. secalis, indicating successful introgression from the donors into the NILs. Approximately two-thirds of the observed RP-NIL polymorphisms were linked to the assumed resistance in the NIL. Based on the marker and phenotypic analyses of the NILs, suggestions for a more appropriate and updated terminology of genes for resistance to R. secalis in barley are made. The proposed changes in nomenclature also indicate the differentials that are available as NILs and those lacking.

Zoledronic acid versus pamidronate in the treatment of skeletal metastases in patients with breast cancer or osteolytic lesions of multiple myeloma: a phase III, double-blind, comparative trial

PURPOSE

Zoledronic acid, a new and more potent bisphosphonate, was compared with pamidronate, the current standard treatment for patients with osteolytic or mixed bone metastases/lesions.

PATIENTS AND METHODS

A total of 1,648 patients with either Durie-Salmon stage III multiple myeloma or advanced breast cancer and at least one bone lesion were randomly assigned to treatment with either 4 or 8 mg of zoledronic acid via 15-minute intravenous infusion or 90 mg of pamidronate via 2-hour intravenous infusion every 3 to 4 weeks for 12 months. The primary efficacy endpoint was the proportion of patients experiencing at least one skeletal-related event over 13 months.

RESULTS

The proportion of patients with at least one skeletal-related event was similar in all treatment groups. Median time to the first skeletal-related eventwas approximately 1 year in each treatment group. The skeletal morbidity rate was slightly lower in patients treated with zoledronic acid than in those treated with pamidronate, and zoledronic acid (4 mg) significantly decreased the incidence and event rate for radiation therapy to bone, both overall and in breast cancer patients receiving hormonal therapy. Pain scores decreased in all treatment groups in the presence of stable or decreased analgesic use. Zoledronic acid (4 mg) and pamidronate were equally well tolerated; the most common adverse events were bone pain, nausea, fatigue, and fever and < 5% of serious adverse events were related to the study drug. The incidence of renal impairment among patients treated with 4 mg of zoledronic acid via 15-minute infusion was similar to that among patients treated with pamidronate.

CONCLUSIONS

Zoledronic acid (4 mg) via 15-minute intravenous infusion was as effective and well tolerated as 90 mg of pamidronate in the treatment of osteolytic and mixed bone metastases/lesions in patients with advanced breast cancer or multiple myeloma. (Can-

Frequency of celiac disease in individuals with Down syndrome in the United States

Ninety-three individuals with Down syndrome (DS) were screened to investigate the prevalence of celiac disease (CD) in the United States. Five of the 93 individuals were antiendomysial antibody (EMA) positive. Of the 5 who tested positive for EMA, 4 were biopsied, 1 refused biopsy. Three of the 4 individuals biopsied manifested changes of CD on small bowel biopsy. This gives a frequency of 3.2% of confirmed CD in our DS individuals and suggests the need for periodic screening for celiac disease in this population.

Recombinant human acid alpha-glucosidase enzyme therapy for infantile glycogen storage disease type II: results of a phase I/II clinical trial

PURPOSE

Infantile glycogen storage disease type II (GSD-II) is a fatal genetic muscle disorder caused by deficiency of acid alpha-glucosidase (GAA). The purpose of this study was to investigate the safety and efficacy of recombinant human GAA (rhGAA) enzyme therapy for this fatal disorder.

METHODS

The study was designed as a phase I/II, open-label, single-dose study of rhGAA infused intravenously twice weekly in three infants with infantile GSD-II. rhGAA used in this study was purified from genetically engineered Chinese hamster ovary (CHO) cells overproducing GAA. Adverse effects and efficacy of rhGAA upon cardiac, pulmonary, neurologic, and motor functions were evaluated during 1 year of the trial period. The primary end point assessed was heart failure-free survival at 1 year of age. This was based on historical control data that virtually all patients died of cardiac failure by 1 year of age.

RESULTS

The results of more than 250 infusions showed that rhGAA was generally well tolerated. Steady decreases in heart size and maintenance of normal cardiac function for more than 1 year were observed in all three infants. These infants have well passed the critical age of 1 year (currently 16, 18, and 22 months old) and continue to have normal cardiac function. Improvements of skeletal muscle functions were also noted; one patient showed marked improvement and currently has normal muscle tone and strength as well as normal neurologic and Denver developmental evaluations. Muscle biopsies confirmed that dramatic reductions in glycogen accumulation had occurred after rhGAA treatment in this patient.

CONCLUSIONS

This phase I/II first study of recombinant human GAA derived from CHO cells showed that rhGAA is capable of improving cardiac and skeletal muscle functions in infantile GSD-II patients. Further study will be needed to assess the overall potential of this therapy.

Concurrent weekly carboplatin and radiotherapy for nasopharyngeal carcinoma: report of a joint phase II study

We report a phase I/II study of weekly concurrent carboplatin and radiotherapy in patients with nasopharyngeal carcinoma (M0 stage). Of 47 patients registered, 45 completed the treatment course. Twenty-six (55%) (95% CI, 41-69%) patients experienced > or =grade 3 acute toxicity (RTOG). Five (11%) (95% CI, 2-20%) patients experienced > or =grade 3 chronic toxicity. This regimen appears to have acceptable toxicity compared to the experimental arm of Phase III Intergroup Study 0099, but progression-free and overall survival are probably inferior. At present, there is no data to suggest that carboplatin can replace cisplatin for concurrent chemoradiation for NPC.