Appreciating the links between heart failure and depression

Depression and heart failure frequently occur together, symptoms overlap and the prognosis is worsened. Both conditions share biopsychosocial risk factors and are accompanied by behavioural/lifestyle, neurohormonal, inflammatory and autonomic changes that are implicated aetiologically. Depression has been conceptualized as a decompensated response to allostatic overload, wherein adaptive psychological, behavioural and physiological responses to chronic and/or severe stress, become unsustainable. Heart failure can similarly be viewed as a decompensated response to circulatory overload, wherein adaptive functional (neurohormonal effects on circulation, inotropic effects on heart) and structural (myocardial remodelling) changes, become unsustainable. It has been argued that the disengaged state of depression can initially be protective, limiting an individual's exposure to external challenges, such that full recovery is often possible. In contrast, heart failure, once past a tipping-point, can progress relentlessly. Here, we consider the bidirectional interactions between depression and heart failure. Targeted treatment of depression in the context of heart failure may improve quality of life, yet overall benefits on mortality remain elusive. However, effective treatment of heart failure typically enhances function and improves key psychological and behavioural determinants of low mood. Prospectively, research that examines the mechanistic associations between depression and heart failure offers fresh opportunity to optimize personalized management in the advent of newer interventions for both conditions.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

1129 Sex Dependent Effects on Sleep Architecture After Traumatic Brain Injury: Impact on Outcome

Introduction

Traumatic Brain Injury (TBI) is frequently associated with problems with sleep and diurnal somnolence. After determining if subjective somnolence was associated with sleep disturbances, we investigated if alterations in sleep architecture were associated with cognitive, social and emotional health in a sex dependent manner. For patients receiving positive airway pressure (PAP) treatment, we determined if lack of compliance contributed to cognitive and quality of life issues.

Methods

Adult TBI subjects (n=57) were assessed via overnight polysomnography. Mean age was 41 years and mean TBI chronicity was 2.5 years. Overall level of disability was determined by the Mayo Portland Inventory II. Sleep measures included slow wave sleep (SWS), REM latency, percent time in all sleep stages, apnea/hypopnea index, wake after sleep onset (WASO), and arousal index. Outcome measures were the California Verbal Learning Test (CVLT), Montreal Cognitive Assessment (MoCA), Trails A and B, Beck Depression Inventory, and Neuro-QoL.

Results

No sex effects for reporting somnolence were found. Besides being associated with increased subjective anxiety and stigma, somnolence was associated with increased arousals, decreases in SWS and higher incidence of REM AHI. WASO and number of arousals had a negative impact on the amount of SWS and sleep efficiency. Men spent significantly more time in REM sleep, which was correlated with higher scores on the MoCA and CVLT. Women showed more disability. Longer latencies to SWS were associated with increased CVLT performance. AHI was associated with increases in emotional/behavioral dyscontrol, fatigue and self-reported sleep disturbance. All effects were statistically significant.

Conclusion

Female TBI patients show significant impairments in REM sleep, which may impact learning and memory. Sleep disturbances were associated with poorer cognitive performance and may ultimately affect outcome, as indicated by lower scores on quality of life measures.

Support

Centre for Neuro Skills

P5645Lifetime sex-specific sudden cardiac death prediction using ECG global electrical heterogeneity: the atherosclerosis risk in communities (ARIC) study

Background

Sex-based differences in sudden cardiac death (SCD) exist and screening methods for SCD are inadequate.

Purpose

To develop sex-specific lifetime risk prediction models using electrocardiographic (ECG) global electrical heterogeneity (GEH) and clinical characteristics.

Methods

Participants from the Atherosclerosis Risk in Communities study with analyzable ECGs (n=14,725; age, 54.2±5.8 yrs; 55% female, 74% white) were followed up for 24.4 years (median). Traditional ECG and GEH variables were measured on 12-lead ECGs. A Cox regression model was used to develop a prediction model. In women, the final model included race, age, coronary heart disease (CHD), stroke, hypertension, diabetes, smoking, high-density lipoprotein, albumin, uric acid, education level, heart rate, QTc, sum absolute QRST integral, spatial peak QRS-T angle. In men, the final prediction model included age, race, CHD, stroke, hypertension, diabetes, total cholesterol, physical activity, smoking, serum phosphorus, albumin, chronic kidney disease, spatial area QRS-T angle, area spatial ventricular gradient (SVG) elevation and magnitude, and peak SVG magnitude.

Results

There were a total of 530 SCDs. Our prediction models showed robust prediction of SCD in both sexes [(Harrell's C-statistic women 0.863 (95% CI 0.845–0.882), men 0.786 (95% CI 0.786–0.803)]. In women when ECG and GEH variables were added to clinical variables, the net reclassification improved by 9% (P=0.001) (Table). In men there was no significant reclassification improvement.

Net reclassification Lifetime SCD Risk: Clinical + ECG + GEH Variables Women Men <5% 5–15% >15% Total <5% 5–15% >15% Total SCD Cases <5% 82 14 0 96 103 16 0 119 5–15% 7 59 10 76 12 116 12 140 >15% 0 0 20 20 0 5 74 79 Lifetime SCD Risk: Total 89 73 30 192 115 137 86 338 Clinical Variables Only Non-Cases <5% 6,956 131 2 7,089 4,411 264 0 4,675 5–15% 180 509 42 731 210 1,059 48 1,317 >15% 0 28 84 112 0 56 214 270 Total 7,136 668 128 7,932 4,621 1,379 262 6,262

Conclusions

We were the first to develop sex-specific lifetime SCD prediction models. The addition of ECG GEH to clinical variables improved SCD risk reclassification in women, but not in men. Prediction of SCD was more accurate in women as compared to men.

Intravenous tranexamic acid and lower limb arthroplasty-a randomised controlled feasibility study

Tranexamic acid (TA) is widely reported to reduce bleeding and the risk of blood transfusion in patients undergoing lower limb arthroplasty. No study in this setting has had adequate power to examine for the effect of TA on either uncommon, but clinically important, adverse events or patient-centric endpoints. A large randomised controlled trial (RCT) is required to address these questions. As a preliminary feasibility study, we conducted an investigator-initiated, prospective, randomised, double blind placebo-controlled trial in 140 patients, aged 45 years or older, undergoing elective primary or revision hip or knee joint replacement. Subjects were randomised to receive intravenous (IV) TA or a placebo. The primary endpoints were the proportion of patients receiving allogenic blood transfusion and the feasibility of extending our trial methodology to a large trial of TA in this population. Secondary endpoints included a range of adverse clinical and surgical events as well as several patient-centric questionnaires. Red blood cell transfusion occurred in 15% of all patients prior to discharge from hospital. Transfusion rates were significantly different between the TA and placebo groups (8.5% versus 21.7%, <i>P</i>=0.03). Three out of four feasibility endpoints were met, with recruitment being slower than expected. No significant differences were seen between groups in the secondary endpoints. Despite a lower rate of transfusion than that widely reported, IV TA reduced transfusion in patients undergoing lower limb arthroplasty. Our trial methodology would be feasible in the setting of a large multicentre study to investigate whether TA is safe and reduces bleeding in lower limb arthroplasty.

Paediatric antiepileptic polytherapy: systematic review of efficacy and neurobehavioural effects and a tertiary centre experience

AIM

This paper presents the prevalence of antiepileptic polytherapy at a single tertiary institution and systematically reviews the evidence base for its efficacy and neurobehavioural safety in children.

METHOD

Prevalence of antiepileptic polypharmacy was determined from pharmacy dispensing records at a paediatric tertiary hospital and neurobehavioural comorbidities quantified through casenote review; comparison is made with studies evaluating the neurobehavioural safety of antiepileptic polytherapy, identified via systematic literature review.

RESULTS

Amongst 262 patients at the hospital, 117 (44.7%) were prescribed polytherapy; with patients having an intellectual disability statistically more likely to be prescribed polytherapy than those without (70.5% vs 40.6%; p < 0.0001). Systematic review identified no trials addressing the efficacy or neurobehavioural outcomes of polytherapy as a primary outcome. Several observational studies identified associations between polytherapy and neurobehavioural adverse outcomes such as anxiety and behavioural disturbance. Observational studies also suggest that a reduction in polytherapy load is generally not associated with worsening seizure control.

CONCLUSION

Whilst antiepileptic polytherapy is common practice within paediatric epilepsy cohorts attending tertiary care institutions, evidence is lacking to support its efficacy. There are significant practical difficulties to undertaking randomised controlled trials within this population. Nonetheless, clinicians must consider that adverse neurobehavioural consequences of polytherapy might outweigh benefits to seizure control.

Neuraxial analgesia is not associated with an increased risk of post-partum relapses in MS

Background:

Obstetrical analgesia remains a matter of controversy because of the fear of neurotoxicity of local anesthetics on demyelinated fibers or their potential relationship with subsequent relapses.

Objective:

To assess the impact of neuraxial analgesia on the risk of relapse during the first 3 months post-partum, with a focus on women who experienced relapses during pregnancy.

Methods:

We analyzed data of women followed-up prospectively during their pregnancies and at least 3 months post-partum, collected in the Pregnancy in Multiple Sclerosis (PRIMS) and Prevention of Post-Partum Relapses with Progestin and Estradiol in Multiple Sclerosis (POPARTMUS) studies between 1992–1995 and 2005–2012, respectively. The association of neuraxial analgesia with the occurrence of a post-partum relapse was estimated by logistic regression analysis.

Results:

A total of 389 women were included, 215 from PRIMS and 174 from POPARTMUS. In total, 156 women (40%) had neuraxial analgesia. Overall, 24% experienced a relapse during pregnancy and 25% in the 3 months post-partum. Women with a pregnancy relapse were more likely to have a post-partum relapse (odds ratio (OR) = 1.83, p = 0.02), independently of the use of neuraxial analgesia. There was no association between neuraxial analgesia and post-partum relapse (OR = 1.08, p = 0.78).

Conclusion:

Neuraxial analgesia was not associated with an increased risk of post-partum relapses, whatever multiple sclerosis (MS) activity during pregnancy.

Abstract P1-14-06: Selective internal radiation therapy (SIRT) with Yttrium-90 resin microspheres and FOLFOX/5FU chemotherapy in pre-treated breast cancer patients with liver metastases: A retrospective analysis of response rates, times to progression and survival of patients treated in Manchester UK between 2010 and 2016

Background:

SIRT is a globally licensed technique of Radio-Embolization (RE) of hepatic tumors via intra-arterial infusion of β-particle emitting Yttrium-90 (Y-90) radio-labelled microspheres. It increases response rates and hepatic time to progression in metastatic colorectal cancer when used in combination with 5FU/Oxaliplatin (FOLFOX) chemotherapy with acceptable toxicity profile. FOLFOX gives a radio-sensitizing effect and also controls disease outside the liver. Breast cancer liver metastases (BCLM) patients often have extra-hepatic disease and respond to multiple lines of systemic therapy and SIRT is infrequently used.

Methods and patients

Between 2010 and 2016 we treated 25 BCLM patients with Y-90 SIRT.

Receptor status: 20 ER+ve/HER-2 -ve, 3 ER-ve/HER-2 +ve, 2 triple -ve.

Eleven patients had liver only disease with 14 also having known extra-hepatic disease. Average number of previous lines of therapy in metastatic setting: chemotherapy = 2.4; endocrine = 1. Sixty-four % patients had prior Capecitabine (n=16); 12% platinum (n=3, all Carboplatin). Twenty patients received chemotherapy with SIRT: 17 had modified FOLFOX6 (Oxaliplatin/bolus 5FU day1, infusional 5FU day 1-3 (46 hrs); 3 patients had Modified de Gramont style 5FU alone. Five patients had no chemotherapy.

Sir-spheres were inserted on day 2 of FOLFOX with the 5FU infusion pump continuing to day 3. Further 2-weekly FOLFOX chemo cycles were at clinician's discretion: average number delivered 3.8. Four patients had the liver treated in two halves, approximately 6 weeks apart. One patient received SIRT only to half the liver. Patients were imaged with PET-CT/CT before and 2-3 months after SIRT. Retrospective case note review was performed and data correlated to evaluate tumor response (RR); hepatic and extra hepatic progression free survival (HPFS and EHPFS) and overall survival (OS). Accurate toxicity data was not recorded.

Results

Hepatic CT response rates: PR 56% (n=14), SD 28% (n=7) and PD 16% (n=4). Hepatic PET response rates: CR 32% (n=8), PR 40% (n=10), SD 12% (n=3), PD 16%(n=4). (Overall PET liver disease control rate = 84%).

Eight patients (32%) had extra-hepatic PD at first assessment. Of them, 4 had PR, 2 SD and 2 PD in the liver at that assessment. Two HER-2 +ve patients had brain metastases as first sign of PD within 75 days, an area not previously screened. Of 16 pre-treated with Capecitabine, liver CT response rates: 62.5% PR, 18.75% SD (n=10,3). Post SIRT/FOLFOX, average number of therapy lines: 2 for chemo and 0.75 for endocrine, with 8 patients still alive at time of censoring.

Median OS: 766 HPFS: 210 days (CI 140-286). Median EHPFS in patients with extra-hepatic disease: 152 days (CI 96-636).

Conclusions

SIRT with FOLFOX in previously treated BCLM patients produces high response rates, excellent tumor control and time to progression in the liver with good overall survival. It does not seem to decrease the ability to give further lines of chemotherapy and can be considered as an option for breast cancer patients with liver metastases.

Citation Format: Wilson G, Mullamitha S, Bentley D, Bell J, Mullan D, Carter L, Chittalia A, Howell S, Laasch H-U, Westwood T, Jeans S, Tipping J, Ryder D, Farquharson F, Arumugam P, Sheen A, Rajashanker B, Armstrong A, Misra V, Manoharan P, Lawrance J. Selective internal radiation therapy (SIRT) with Yttrium-90 resin microspheres and FOLFOX/5FU chemotherapy in pre-treated breast cancer patients with liver metastases: A retrospective analysis of response rates, times to progression and survival of patients treated in Manchester UK between 2010 and 2016 [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 P1-14-06.

Alignment options for total knee arthroplasty: A systematic review

In spite of improvements in implant designs and surgical precision, functional outcomes of mechanically aligned total knee arthroplasty (MA TKA) have plateaued. This suggests probable technical intrinsic limitations that few alternate more anatomical recently promoted surgical techniques are trying to solve. This review aims at (1) classifying the different options to frontally align TKA implants, (2) at comparing their safety and efficacy with the one from MA TKAs, therefore answering the following questions: does alternative techniques to position TKA improve functional outcomes of TKA (question 1)? Is there any pathoanatomy not suitable for kinematic implantation of a TKA (question 2)? A systematic review of the existing literature utilizing PubMed and Google Scholar search engines was performed in February 2017. Only studies published in peer-reviewed journals over the last ten years in either English or French were reviewed. We identified 569 reports, of which 13 met our eligibility criteria. Four alternative techniques to position a TKA are challenging the traditional MA technique: anatomic (AA), adjusted mechanical (aMA), kinematic (KA), and restricted kinematic (rKA) alignment techniques. Regarding osteoarthritic patients with slight to mid constitutional knee frontal deformity, the KA technique enables a faster recovery and generally generates higher functional TKA outcomes than the MA technique. Kinematic alignment for TKA is a new attractive technique for TKA at early to mid-term, but need longer follow-up in order to assess its true value. It is probable that some forms of pathoanatomy might affect longer-term clinical outcomes of KA TKA and make the rKA technique or additional surgical corrections (realignment osteotomy, retinacular ligament reconstruction etc.) relevant for this sub-group of patients. Longer follow-up is needed to define the best indication of each alternative surgical technique for TKA. Level I for question 1 (systematic review of Level I studies), level 4 for question 2.

Impact of Oncotype DX breast Recurrence Score testing on adjuvant chemotherapy use in early breast cancer: Real world experience in Greater Manchester, UK

BACKGROUND

The National Institute for Health and Clinical Excellence (NICE) recommended the Oncotype DX^® Breast Recurrence Score^® (RS) assay as an option for informing adjuvant chemotherapy decisions in node-negative, oestrogen receptor (ER)+, human epidermal growth factor receptor 2 (HER2)-negative early breast cancer assessed to be at intermediate risk of recurrence based on clinicopathological factors. We evaluated the impact of RS testing on adjuvant chemotherapy decision-making in routine clinical practice in a UK Cancer Network.

METHODS

RS testing was performed in 201 females with newly diagnosed, ER+, HER2-negative, invasive breast cancer who underwent breast surgery with curative intent, were calculated to have a >3% overall survival benefit at 10 years from adjuvant chemotherapy based on PREDICT, and were considered for adjuvant chemotherapy. The impact of RS testing on adjuvant treatment decisions/associated cost was assessed.

RESULTS

In all patients, the multi-disciplinary team recommended chemotherapy but the RS result allowed 127/201 patients (63.2%) to avoid unnecessary adjuvant chemotherapy. Amongst ER+, HER2-negative, node-negative patients (eligible for Oncotype DX testing in UK guidelines), 60.3% were spared chemotherapy. In node-positive patients, the assay reduced the use of chemotherapy by 69.2%. The use of RS testing to guide treatment in these 201 patients was associated with significant cost saving (when considering the cost of RS testing for all patients plus chemotherapy and its associated cost for 74 patients).

CONCLUSIONS

Incorporating RS testing into routine clinical practice for selected node-negative and node-positive breast cancer patients significantly reduces the use of chemotherapy (p < 0.001) with its associated morbidity and costs.

Response to Comment on "Sensitivity of seafloor bathymetry to climate-driven fluctuations in mid-ocean ridge magma supply"

Tolstoy reports the existence of a characteristic 100 thousand year (ky) period in the bathymetry of fast-spreading seafloor but does not argue that sea level change is a first-order control on seafloor morphology worldwide. Upon evaluating the overlap between tectonic and Milankovitch periodicities across spreading rates, we reemphasize that fast-spreading ridges are the best potential recorders of a sea level signature in seafloor bathymetry.

Response to Comment on "Sensitivity of seafloor bathymetry to climate-driven fluctuations in mid-ocean ridge magma supply"

Huybers et al present new bathymetric spectra from an intermediate-spreading ridge as evidence for a primary contribution of sea level cycles to the morphology of the seafloor. Although we acknowledge the possibility that sea level-modulated magmatic constructions may be superimposed on a first-order tectonic fabric, we emphasize the difficulty of deciphering these different contributions in the frequency domain alone.

Sensitivity of seafloor bathymetry to climate-driven fluctuations in mid-ocean ridge magma supply

Recent studies have proposed that the bathymetric fabric of the seafloor formed at mid-ocean ridges records rapid (23,000 to 100,000 years) fluctuations in ridge magma supply caused by sealevel changes that modulate melt production in the underlying mantle. Using quantitative models of faulting and magma emplacement, we demonstrate that, in fact, seafloor-shaping processes act as a low-pass filter on variations in magma supply, strongly damping fluctuations shorter than about 100,000 years. We show that the systematic decrease in dominant seafloor wavelengths with increasing spreading rate is best explained by a model of fault growth and abandonment under a steady magma input. This provides a robust framework for deciphering the footprint of mantle melting in the fabric of abyssal hills, the most common topographic feature on Earth.

Loss of DNA mismatch repair due to knockout of MSH2 or PMS2 results in resistance to cisplatin and carboplatin

Loss of DNA mismatch repair is a common finding in hereditary nonpolyposis colon cancer as well as in many types of sporadic human tumors. The effect of loss of DNA mismatch repair activity on sensitivity to cisplatin and carboplatin was tested using MSH2 and PMS2 knockout cell lines. The knockout dMsh2 embryonic stem cell line was 2.1-fold more resistant to cisplatin and 1.7-fold more resistant to carboplatin when compared to the isogenic wild-type wt-2 cell line. Likewise, the PMS2(-/-) mouse fibroblasts were 1.9-fold more resistant to cisplatin and 1.5-fold more resistant to carboplatin when compared to the isogenic PMS2(+/+) fibroblasts. These findings demonstrate that loss of mismatch repair due to knockout of either MSH2 or PMS2 results in low-level resistance to cisplatin and carboplatin, drugs that form the same types of adducts in DNA. These data validate results previously obtained using non-isogenic mismatch repair-proficient and -deficient cell lines, and indicate that simple recognition of the cisplatin adduct by the MSH2/MSH6 heterodimer is not sufficient for full detector function, but that PMS2 is also required for the pro-apoptotic signal to be generated from this detector.

Association between hsp60 messenger-RNA levels and Cisplatin resistance in human head and neck-cancer cell-lines

Development of resistance to cisplatin (cDDP) is a major obstacle in the cure of many cancers. Recently, a cDNA from cDDP-resistant human ovarian carcinoma cells was identified as the mitochondrial hsp60 chaperonin. The aim of this study was to determine the changes in expression of hsp60 during selection for cDDP resistance in two head and neck cancer cell lines, UMSCC5 and UMSCC10b and whether the emergence of resistance could be correlated with the level of hsp60 expression. We have selected cDDP-resistant variants of two squamous cell carcinoma cell lines, the UMSCC5 and UMSCC10b with levels of resistance varying from 1.5 to 6-fold. Concomitant with the emergence of resistance, the basal level of hsp60 increased 2 to 3-fold. In addition, less cDDP resistance as well as lower hsp60 levels were detected in cDDP resistant variants of the UMSCC10b cell line when selected in the presence of tamoxifen, suggesting a correlation between the intrinsic level of hsp60 expression and cDDP resistance. Using linear regression analysis both UMSCC5 and UMSCC10b cell lines demonstrated a high degree of correlation with coefficients of 0.91 and 0.90, respectively. In conclusion, the expression of hsp60 was closely related to the development of cDDP resistance and could be used as a marker for the emergence of cDDP resistance.

The clinical effectiveness and cost-effectiveness of genotyping for CYP2D6 for the management of women with breast cancer treated with tamoxifen: a systematic review

BACKGROUND

Breast cancer is the most common cancer affecting women in the UK. Tamoxifen (TAM) is considered as the standard of care for many women with oestrogen receptor positive breast cancer. However, wide variability in the response of individuals to drugs at the same doses may occur, which may be a result of interindividual genetic differences (pharmacogenetics). TAM is known to be metabolised to its active metabolites N-desmethyl TAM and 4-hydroxytamoxifen by a number of CYP450 enzymes, including CYP2D6, CYP3A4, CYP2C9, CYP2C19 and CYP2B6. N-desmethyl TAM is further metabolised to endoxifen by CYP2D6. Endoxifen, which is also formed via the action of CYP2D6, is 30- to 100-fold more potent than TAM in suppressing oestrogen-dependent cell proliferation, and is considered an entity responsible for significant pharmacological effects of TAM. Thus, an association between the cytochrome P450 2D6 (CYP2D6) genotype and phenotype (expected drug effects) is believed to exist and it has been postulated that CYP2D6 testing may play a role in optimising an individual's adjuvant hormonal treatment.

OBJECTIVES

To determine whether or not testing for cytochrome P450 2D6 (CYP2D6) polymorphisms in women with early hormone receptor positive breast cancer leads to improvement in outcomes, is useful for health decision-making and is a cost-effective use of health-care resources.

DATA SOURCES

Relevant electronic databases and websites including MEDLINE, EMBASE and HuGENet [Centers for Disease Control and Prevention (Office of Public Health Genomics), Human Genome Epidemiology Network] were searched until July 2009. Further studies that became known to the authors via relevant conferences or e-mail alerts from an automatically updated search of the Scopus database were also included as the review progressed, up to March 2010.

REVIEW METHODS

A systematic review of the clinical effectiveness and cost-effectiveness of CYP2D6 testing was undertaken. As it was not possible to conduct meta-analyses, data were extracted into structured tables and narratively discussed. An exploratory analysis of sensitivity and specificity was undertaken. A review of economic evaluations and models of CYP2D6 testing for patients treated with TAM was also carried out.

RESULTS

A total of 25 cohorts were identified which examined clinical efficacy (overall survival and relapse/recurrence), adverse events and endoxifen plasma concentrations by genotype/phenotype. Significantly, six cohorts suggest extensive metabolisers (Ems) appear to have better outcomes than either poor metabolisers (PMs) or PMs + intermediate metabolisers in terms of relapse/recurrence; however, three cohorts report apparently poorer outcomes for EMs (albeit not statistically significant). There was heterogeneity across the studies in terms of the patient population, alleles tested and outcomes used and defined. One decision model proposing a strategy for CYP2D6 testing for TAM was identified, but this was not suitable for developing a model to examine the cost-effectiveness of CYP2D6 testing. It was not possible to produce a de novo model because of a lack of data to populate it.

CONCLUSION

This is a relatively new area of research that is evolving rapidly and, although international consortia are collaborating, the data are limited and conflicting. Therefore, it is not possible to recommend pharmacogenetic testing in this patient population. Future research needs to focus on which alleles (including, or in addition to, those related to CYP2D6) reflect patient response, the link between endoxifen levels and clinical outcomes, and the appropriate pathways for implementation of such pharmacogenetic testing in patient care pathways.

P1-12-16: HER-2 Testing and Treatment – Is Age a Factor?

Aims: Elderly breast cancer patients have a poorer prognosis due to late diagnosis and sub-optimal treatment. In the UK, HER-2 testing was introduced in 2005 and we sought to determine whether HER-2 testing was performed on patients of all ages and whether HER-2 positive patients of all ages subsequently received Herceptin, from implementation in 2005 until 2008.

Methods: Review of all newly diagnosed breast cancers in women over 50 in our Unit between January 2005 and December 2008 was performed. Cases were identified from the hospital pathology electronic database. Patients were considered HER-2 positive if tissue sections scored 3+ on immunohistochemical analysis (intense membranous staining) or if gene amplification was detected using fluorescence in-situ hybridisation (FISH). Patients were eligible for treatment with Herceptin if the tumour exceeded 1cm in size or if they had lymph-node positive disease, per UK guidelines. Herceptin treatment was determined for all patients.

Results: In total 703 patients with a median age of 68 years (range 56 to 98) were identified and 628 (89.3%) underwent definitive surgery (mastectomies: 246; wide local excisions: 382) and axillary surgery. In total 371 patients (52.8%) underwent HER-2 testing by immunohistochemistry or FISH. HER-2 tests performed by year: 2005 (51/131; 38.9%); 2006 (59/187; 31.6%); 2007 (71/189; 37.6%) and 2008 (190/196; 96.9%). Fifty six patients (15.1%) were HER-2 positive by immunohistochemistry or FISH. Median age of HER2 positive patients was 66 years (range 57 to 98); median age of HER2 negative patients was 68 years (range 56 to 96). Forty four HER-2 positive patients (78.6%) were eligible for treatment with Herceptin; of these 28 patients (63.6%) were treated with Herceptin. HER2 testing, treatment with Herceptin and overall 5-year mortality rate for patients between 50 to 69 years and patients aged 70 years or older is summarised in Table1.

A preliminary examination of the effects of genetic variants of redox enzymes on susceptibility to oedematous malnutrition and on percentage cytotoxicity in response to oxidative stress in vitro

BACKGROUND

The causes of oedematous vs non-oedematous childhood malnutrition (OM vs NOM) remain elusive. It is possible that inherited differences in handling oxidant stressors are a contributing factor.

AIMS

To test for associations between polymorphisms in five genes and (i) risk of OM, a case-control study, and (ii) percentage cytotoxicity in peripheral blood mononuclear cells (PBMCs) exposed to hydrogen peroxide (H(2)O(2)), an in vitro cell challenge study.

METHODS

Participants had been admitted previously for treatment of OM (cases, n = 74) or NOM (controls, n = 50), or were an independent set of healthy pregnant women (n = 47) who donated peripheral blood mononuclear cells. We tested for associations between genetic variation and outcome using single markers or a bivariate score constructed by counting numbers of deleterious alleles for each of 15 possible pairs of markers.

RESULTS

In the case-control study there were no significant single-marker associations with OM. We did find that higher bivariate scores were associated with OM for the pair of NAD(P)H:quinone oxidoreductase 1 and catalase (odds ratio 2·00, 95% CI 1·05-3·82). In the cell challenge experiments, there were no significant associations with percentage cytotoxicity.

CONCLUSIONS

Variation in this small set of genes seems unlikely to have a large impact on either risk of OM or cytotoxicity after H(2)O(2) exposure. The use of larger sample sizes to test the effects of a much larger set of genetic variants will be required in order to determine whether genetic variation contributes to the risk of OM. Such studies have potential for improving our understanding of causal pathways in OM.

Tamoxifen Resistance in Estrogen Receptor Positive (ER+) Breast Cancer Is Driven by Estrogen Receptor Negative (ER-) Cancer Stem-Like Cells

Introduction: Intrinsic and acquired resistance to endocrine therapy significantly reduces survival rates of women with ER+ breast cancer. In the normal breast, multipotent stem cells are ER-. We hypothesised that tumourigenic breast cancer stem-like cells (CSCs) are ER- and therefore function independently of estrogen, representing a novel mechanism of resistance to endocrine therapy.Methods: Three ER+ cell lines, MCF-7, T47D and BT474 were assessed for ER expression by immunocytochemistry (ICC) in monolayer and after CSC enrichment. Putative CSC number was assessed by the non-adherent mammosphere (MS) assay, in the presence and absence of tamoxifen, and by Fluorescence Activated Cell Sorting (FACS) for the markers CD44+/CD24-/low/epithelial specific antigen(ESA)+. The effect of acquired Tamoxifen resistance on the CSC population of two independent Tamoxifen-resistant (TAM-R) MCF-7 variants, from Cardiff (TAM-RCARD) and Copenhagen (TAM-RCOP) was compared to parental, tamoxifen sensitive (TAM-S) controls. In the MS assay both the number and size of colonies were assessed.Results: A small sub-population of ER_ cells were demonstrated in MCF7 (6.1 ± 1.4%), T47D (6.8± 0.5) and BT474 (3.7±1.3) cells by ICC. However, the majority of putative breast CSCs (CD44+/CD24-/low/ESA-) in MCF7 cells were ER_ (73.2 ± 4.6 % p= 0.0007). There was a significant increase in the proportion of ER- cells in TAM-R cell lines (TAM-RCARD 11.6 ± 1.4% p=0.01 and TAM-RCOP 22 ± 4.8% p=0.02 respectively) compared to the parental TAM-S controls. Both TAM-R cell lines demonstrated increased mammosphere forming efficiency (MFE) compared to TAM-S cells (TAM-RCARD 4% vs. 2.5% p=0.03, and TAM-RCOP 8% vs. 3% p=0.007). The putative CSC population (CD44+/CD24-/low/ESA+) was enriched more than 2.5 fold in TAM-R compared to TAM-S parental controls. Compared with controls, the absolute MFE was not affected by Tamoxifen treatment, although mammospheres formed were significantly smaller.Conclusions: The majority of the putative CSC populations in ER+ breast cancer do not express ER. There is an increase in the proportion of putative ER- CSCs in TAM-R MCF7 cell lines. The reduction in MS size suggests that Tamoxifen targets transit amplifying cells but does not reduce the absolute number of CSC in ER+ breast cancers. These findings demonstrate a novel mechanism of endocrine resistance in ER+ breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5125.