A comparison of the efficacy of trastuzumab deruxtecan in advanced HER2-positive breast cancer: active brain metastasis versus progressive extracranial disease alone

BACKGROUND

Trastuzumab deruxtecan (T-DXd) has demonstrated efficacy in patients with brain metastasis (BM), a group historically with poor outcomes. The prevalence of BMs in patients commencing T-DXd is currently unknown. No direct comparisons have been made of the activity of T-DXd in patients with active BM versus those with extracranial progression alone. This real-world study explored the prevalence of BMs in patients commencing T-DXd, the efficacy of T-DXd in active BM versus extracranial progression alone and the safety of T-DXd.

PATIENTS AND METHODS

Patients with human epidermal growth factor receptor 2-positive advanced breast cancer treated with T-DXd between June 2021 and February 2023 at our specialist cancer hospital were identified and notes reviewed. Clinicopathological information, prior treatment, the presence or absence of central nervous system (CNS) disease, outcomes and treatment-emergent adverse events (TEAEs) were recorded.

RESULTS

Twenty-nine female patients, with a median age of 52 years (interquartile range 44-62 years), were identified; the prevalence of BM was 41%. Median number of lines of prior therapy was 2 (range 2-6). At a median follow-up of 13.8 months, median progression-free survival (PFS) for the overall population was 13.9 months [95% confidence interval (CI) 12.4 months-not estimable (NE)], 16.1 months (95% CI 15.1 months-NE) for active BMs and 12.4 months (95% CI 8.3 months-NE) for progressive extracranial disease alone. The 12-month overall survival (OS) rate was 74% (95% CI 59% to 95%) in the overall population, and 83% (95% CI 58% to 100%) and 66% (95% CI 45% to 96%) for active BMs and extracranial disease only, respectively. Most common TEAEs were fatigue, alopecia, and constipation. In nine patients (31%, including two deaths), pneumonitis occurred.

CONCLUSION

In this real-world population, we demonstrate T-DXd to be effective in patients with active BMs and those with progressive extracranial disease alone. PFS and OS were numerically longer in those with active BMs. These data demonstrate that patients with active BM treated with T-DXd have at least comparable outcomes to those with extracranial disease alone. The high rate of pneumonitis warrants further consideration.

Challenging level of rigid-body approach involving numerical elements (CHLORAINE) applied to repeated elastin peptides

Elastic proteins and derived biomaterials contain numerous tandemly repeated peptides along their sequences, ranging from a few copies to hundreds. These repetitions are responsible for their biochemical, biological and biomechanical properties. These sequences are considered to be intrinsically disordered, and the variations in their behavior are actually mainly due to their high flexibility and lack of stable secondary structures originating from their unique amino acid sequences. Consequently, the simulation of elastic proteins and large elastomeric biomaterials using classical molecular dynamics is an important challenge. Here, we propose a novel approach that allows the application of the DURABIN protocol to repeated elastin-like peptides (r-ELPs) in a simple way. Four large r-ELPs were studied to evaluate our method, which was developed for simulating extracellular matrix proteins at the mesoscopic scale. After structure clustering applied on molecular dynamic trajectories of constitutive peptides (5-mers and 6-mers), the main conformations were used as starting points to define the corresponding primitives, further used as rigid body fragments in our program. Contributions derived from electrostatic and molecular hydrophobicity potentials were tested to evaluate their influence on the interactions during simple mesoscopic simulations. The CHLORAINE approach, despite the thinner granularity due to the size of the patterns used, was included in the DURABIN protocol and emerges as a promising way to simulate elastic macromolecular systems.

P11.45.B Improved overall survival following Stereotactic Radiosurgery for brain metastases - a single institution experience

Background

Brain metastases are increasingly common due to longer survival associated with advancements in treatment. Approximately 40% of cancer patients are diagnosed with brain metastases at some point during their disease. Stereotactic radiosurgery (SRS) avoids the neuro-cognitive toxicity associated with whole brain radiotherapy and has been increasingly offered as a treatment alternative for brain metastases. Combined with developments in systemic treatments, this approach has resulted in improved overall survival (OS). This study reviewed patients treated with single fraction SRS at our institution with a primary endpoint of overall survival.

Material and Methods

A retrospective review determined overall survival for 237 patients who received single fraction SRS for 451 brain metastases from solid tumours between 1st January 2017 and 31st December 2021. Primary tumour sites were classified as breast, kidney, colorectal, melanoma, lung or other. SPSS v.27 was used for Kaplan Meier OS determination. The median follow up was 10.3 months. Cox regression analysis assessed the association between Gross Tumour Volume (GTV) and OS.

Results

In this patient cohort, 60% (N=142) were female and 40% (N=95) were male, with a median age of 63 [32-85]. 63.7% (N = 151) had a solitary metastasis. Patients received a single fraction of 15, 17.5 or 20 Gy (prescribed to 80% isodose) dependent on the planning target volume (PTV) size and whether it was initial treatment or re-treatment. 71% of all patients were alive at 6 months with median OS of 12.0 months [10.6-13.4]. Primary tumour site significantly affected OS (Log rank, Chi squared 15.656, p0.008) with breast cancer patients (N=58) surviving longest with a median OS 16.0 months [13.6-18.4] followed by melanoma median OS 15.0 months [7.6-22.4], kidney cancer patients (N = 24) median OS 12.0 months [8.3-15.7] and lung patients (N=87) median OS 10.0 months [8.9-11.3]. The lowest median OS was for colorectal patients at 7.0 months [1.4-12.6]. However, considering the small sample size, N = 15, more data is needed to confirm the significance. The larger the GTV volume the lower the survival time (Chi squared 8.692, p 0.003).

Conclusion

71% of patients had an OS of 6.0 months or more with a median of 12.0 months. As expected, primary tumour site has a significant impact on OS, with breast cancer patients living longest. In addition, increasing GTV size is associated with significantly worse survival. Given the improved survival for these patients, the avoidance of neuro cognitive decline remains of paramount importance and outcomes for these patients need to be reported in future work.

OP0054 REDUCING THE BURDEN OF LOW BACK PAIN: RESULTS FROM A NEW MICROSIMULATION MODEL

Background

Low back pain (LBP) has been the leading cause of disability worldwide for the past 30 years. In 2019, LBP was responsible for 64 million years lived with disability (YLDs) [1].

Objectives

The purpose of the present study was to project and compare the impact of three strategies for reducing the population health burden of LBP: weight loss, ergonomic interventions, and an exercise program.

Methods

We have developed a microsimulation model of LBP in Canada using a novel simulation platform, SimYouLate. The initial population was derived from Cycle 1 (2001) of the Canadian Community Health Survey (CCHS). We modeled an open population 20 years of age and older. Key variables included age, sex, education, body mass index (BMI), type of work, having a back problem, pain level in persons with back problems, and exercise. The effects of interventions on the risk of LBP were obtained from the CCHS for the effect of BMI, the Global Burden of Disease Study for occupational risks, and a published meta-analysis for the effect of exercise. All interventions lasted from 2021 to 2040. Strength of the interventions varied over a wide range. YLDs were defined as LBP prevalence multiplied by disability weight. The population health impact of the interventions was calculated as a difference in YLDs between the base-case scenario and each intervention scenario and expressed as YLDs averted per intervention unit and as % of total LBP-related YLDs.

Results

In the base-case scenario, LBP in 2020 was responsible for 424,900 YLDs in Canada and the amount increased to 460,312 YLDs in 2040. The effects of the interventions on YLDs were as follows: 27,993 (95% CI 23,373, 32,614) YLDs averted over 20 years per 0.1 unit change in log-transformed BMI (10.5% change in BMI) among overweight and obese individuals, 19,416 (16,275, 22,557) YLDs averted per 1% reduction in the proportion of workers exposed to occupational risks, and 26,058 (22,455, 29,661) YLDs averted per 1% increase in the proportion of eligible patients with back problems participating in the exercise program. Table 1 shows the intervention impact as % of total LBP-related YLDs and Figure 1 shows YLD-equivalence between the interventions. A one unit reduction in BMI per year among the overweight and obese individuals would be approximately equivalent in terms of disability reduction to an effective ergonomic intervention in 35% of at-risk workers and an exercise intervention in 27% of eligible patients with back problems over the same period (Figure 1).

Table 1.

YLDs averted between 2021 and 2040 as % of total LBP-related YLDs, according to intervention type and level, in persons aged 20+ in Canada

InterventionEffect (%)95% LCL95% UCLReduction in BMI per year0.11.4-1.44.10.34.82.27.30.56.33.98.81.08.56.011.03.011.99.414.45.013.510.916.0Reduction in occupational exposure20%5.21.98.540%9.56.412.760%13.810.616.980%18.114.821.4100%22.418.825.9Increase in exercise participation20%6.62.810.440%12.48.716.060%18.114.521.780%23.920.127.6100%29.625.533.7

LCL: lower confidence limit. UCL: upper confidence limit.

Figure 1.

Equivalence between BMI, ergonomic and exercise interventions in terms of their impact on YLDs. Each point represents a specific number of YLDs averted. Values on the y-axis show reduction in % of workers at risk and increase in % exercising that are required to achieve the same reduction in YLDs as the corresponding reduction in BMI shown on the x-axis.

Conclusion

This is the first population-based microsimulation study to compare currently available preventive strategies in LBP in terms of YLDs averted and to provide measures of equivalence between these strategies.

References

[1]Hartvigsen J, Hancock MJ, Kongsted A, et al. What low back pain is and why we need to pay attention. Lancet 2018;391(10137):2356-2367.

Acknowledgements

The study was supported by a grant from the Canadian Institutes for Health Research (FRN 142440).

Disclosure of Interests

None declared.

Factors Affecting Trends in Societal Indicators of Ageing Well in Hong Kong: Policies, Politics and Pandemics

OBJECTIVES

To document the trend in a quality of life indicator for the older Hong Kong population as an assessment of the impact of age friendly city policies, political conflicts and the covid-19 pandemic.

DESIGN

Random telephone survey and collection of government data over four years (2017-2020).

SETTING

Community living older people.

PARTICIPANTS

People aged 50 years and over.

MEASUREMENTS

The Hong Kong Quality of Life Index covering four domains of in income security, health status, capability and enabling environment.

RESULTS

From 2017-9, improvements were seen in various domains in parallel with the adoption of the World Health Organization's Age Friendly City concept by government policy together with a territory wide initiative supported by a major philanthropic organization. However scores of all domains dropped markedly as a result of political conflicts as well as the onset of the pandemic.

CONCLUSION

The documentation of the trend in HKEQOL shows that while it may be used as a macro indicator that is able to reflect policies affecting the well-being of older people, it is also able to reflect the impact of societal unrest and pandemics, and that the latter may override the effect of existing ageing policies. It also follows that during social unrest and pandemics, specific policies targeting older people may be needed to maintain well-being.

Adjuvant management of locally advanced oral squamous cell carcinoma - real-world challenges and opportunities

Patients with locally advanced oral squamous cell cancer (LAOSCC) are treated with adjuvant radiotherapy (RT) or chemoradiotherapy (CRT) following surgical ablation. This depends on the pathological risk factors and aims to reduce the risk of local recurrence and improve survival. Delivery of these aggressive treatments is, however, challenging particularly following major surgery. To inform the adaptations necessary to deliver gold-standard therapy, we aimed to describe real-world delivery of multimodality treatment in LAOSCC, in a UK population with high levels of disease incidence and low socioeconomic status. Patients with LAOSCC (T1-4 N1-3/T3-4 N0) who were treated between October 2014 and October 2016 and had a minimum follow up of 24 months were included. They were identified using the Somerset Cancer Register and data were collected through retrospective case note review. Approval was obtained from the audit departments at the relevant NHS institutions, and data were analysed using IBM SPSS Statistics for Windows version 24 (IBM Corp). The analysis included 129 patients with 82% having an initial performance status (PS) of 0-1. The most frequent change in PS was a one point drop (46%). Twenty of the 93 eligible patients (22%) underwent adjuvant CRT. A total of 37 (40%) began adjuvant CRT/RT within 42 days, and 79 (85%) within 56 days. A delay in initiating adjuvant therapy was associated with higher rates of complications and a longer postoperative hospital stay. Concordance between imaging and pathological nodal staging was poor (cK 0.223). PS frequently declines after complex surgical procedures and long postoperative recovery periods, leading to difficulties providing adjuvant treatments within the national guidance of 42 days. Frequent deviation from planned adjuvant therapies highlights the need for improved treatment strategies.

0574 Prevalence and Characteristics of Rapid Eye Movement Obstructive Sleep Apnoea (REM OSA) in a Multi-Ethnic OSA Cohort

Introduction

Recent studies have shown that REM OSA is associated with increased incidence of hypertension and insulin resistance. However, there is a lack of Asian data on REM OSA. Our study aimed to examine the prevalence and characteristics of REM OSA in a multi-ethnic OSA cohort.

Methods

This was a retrospective observational study of all patients who underwent an overnight diagnostic polysomnography at a Singapore tertiary hospital from 1st August 2017 to 31st August 2018. All patients with a diagnosis of OSA (Apnoea Hypopnea Index (AHI) ≥5) were included in the study. REM OSA is defined as an overall AHI≥5, REM AHI/Non REM (NREM) AHI>2, NREM AHI<15 and at least 15 minutes of REM sleep.

Results

457 OSA subjects were included in the analysis. 19% (87/457) had REM OSA. Univariate analysis showed that REM OSA was more prevalent among female OSA than male OSA [34/115 (29.6%) versus 53/342 (15.5%) respectively, p<0.001]. Compared to non REM OSA, REM OSA had milder OSA severity [mean AHI 12.74±4.71 versus 45.34±28.38, p<0.001] and lower prevalence of hypertension [21/87 (24.1%) versus 138/370(37.3%), p=0.02]. No differences were found between both groups for age (p=0.273), ethnicity (p=0.615), Body Mass Index (p=0.336), diabetes mellitus (p=0.245) and Epworth Sleepiness Scale (0.06). Gender and OSA severity differences between both groups remained statistically significant in multivariate analysis (higher prevalence of REM OSA in female, p=0.043 and milder disease severity in REM OSA, p=0.006).

Conclusion

REM OSA was common in our OSA cohort and had higher prevalence in female and milder disease severity compared to non REM OSA. However, we did not find an increased prevalence of hypertension or diabetes mellitus in REM OSA. Further population-based study on REM OSA is needed to understand this phenotype better.

Support

NIL

Three-year longitudinal cognitive functioning in patients recently diagnosed with bipolar disorder

OBJECTIVE

The longitudinal course of neuropsychological functioning after the first manic episode in bipolar disorder is unknown. The present study evaluated cognitive change in bipolar disorder in the first 3 years after the initial manic episode.

METHODS

Ninety-one newly diagnosed patients with bipolar disorder and 61 demographically similar healthy participants received a neuropsychological evaluation assessing multiple cognitive domains at baseline, 1-year, and 3-year time points. Patients also received clinical assessments including mood ratings at all time points.

RESULTS

Patients showed deficits in all domains at baseline, but similar longitudinal trajectories across time relative to healthy participants in most cognitive domains. For processing speed, patients showed more gains than controls from baseline to 1 year, but these gains stabilized thereafter. Patients with alcohol/substance abuse showed an initial delay but subsequent recovery in executive functioning. Patients who discontinued antipsychotic treatment showed better cognitive outcomes in verbal memory.

CONCLUSION

Appropriately treated patients with bipolar disorder showed favorable cognitive outcome in the first 3 years after experiencing an initial manic episode, arguing against cognitive neuroprogression at this stage of the illness. Discontinuation of antipsychotic treatment may be associated with better cognitive outcomes, but clarification of the role of antipsychotics on cognitive functioning requires further investigation.

IRF4-induced upregulation of lncRNA SOX2-OT promotes cell proliferation and metastasis in cholangiocarcinoma by regulating SOX2 and PI3K/AKT signaling

OBJECTIVE

The aim of this study was to investigate the role of lncRNA SOX2-OT in the proliferation and metastasis of cholangiocarcinoma (CCA) and its underlying mechanisms.

PATIENTS AND METHODS

A total of 82 patients with CCA underwent surgery in our hospital were enrolled in this study. Five CCA cell lines (HuH-28, QBC939, HuCCT1, CCLP1, RBE) were used. The ability of proliferation and metastasis of CCA cells were detected by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay, colony formation assay, and transwell assay, respectively. Additionally, in vivo tumor metastasis assay was done. Furthermore, the Kaplan Meier method was used to validate the prognostic importance of SOX2-OT for patients with cholangiocarcinoma. Besides, the protein and mRNA expression of CCA cells were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot, respectively.

RESULTS

The expression level of lncRNA SOX2-OT was significantly upregulated in cholangiocarcinoma tissues. Functional assays were further conducted to prove the oncogenic role of SOX2-OT on the proliferation and metastasis of cholangiocarcinoma cells. Furthermore, mechanism investigations manifested that transcription factor IRF4 upregulates SOX2-OT by promoting the transcriptional activity of SOX2-OT. SOX2-OT could positively regulate the nearby gene SOX2. SOX2-OT suppressed the nuclear transcription of PTEN, thereby activating PI3K/AKT signaling.

CONCLUSIONS

lncRNA SOX2-OT upregulated by IRF4 promotes cell proliferation and metastasis in cholangiocarcinoma via upregulating SOX2 and activating PI3K/AKT signaling pathway.

The application of a haemorrhage assessment tool in evaluating control of bleeding in a pilot trauma haemorrhage trial

OBJECTIVES

To determine whether it was feasible to use a haemorrhage assessment tool (HAT) within a trauma trial and whether the data obtained could differentiate patients who had achieved haemostasis.

BACKGROUND

Major haemorrhage is one of the leading causes of death worldwide, affecting 40% of trauma patients. Clinical trials evaluating haemostatic interventions often use transfusion outcomes as a primary endpoint. Transfusion is highly dependent on local practice, limiting its reliability as a robust, transferable endpoint.

METHODS

A five-point HAT questionnaire was applied to participants enrolled into the EFIT-1 trial. This RCT evaluated the feasibility of administering a 6 g fibrinogen concentrate to patients with severe trauma haemorrhage.

RESULTS

Of participants, 98% completed a HAT; 75% participants had 'achieved haemostasis' at the time of tool completion, as determined by clinical acumen alone. HAT scores were able to differentiate which participants required transfusion after 3 h. Of participants, 56% were transfused red blood cells when they scored 0-2, compared to 17% with HAT scores between 3 and 5.

CONCLUSION

This study has confirmed the feasibility of using a HAT during the emergency care of patients suffering trauma haemorrhage, and future studies should be conducted to determine its value as an endpoint in haemostasis studies.

Clinico-radiological correlation of magnetic resonance imaging findings in patients with idiopathic intracranial hypertension

PURPOSE

Although several studies have reported imaging findings associated with idiopathic intracranial hypertension (IIH), less is known about the correlation between imaging findings and IIH-related symptoms or signs. Our study aimed to determine if clinical features of IIH are correlated with magnetic resonance imaging (MRI) features.

METHODS

A retrospective chart review was conducted on consecutive patients presenting at the neuro-ophthalmology department over the last 15 years. All patients diagnosed with IIH were identified and those with available MRI were included in the final analysis. All MRI images were reviewed by a neuroradiologist blinded to the presenting symptoms and signs. Statistical analysis was performed to determine the correlation between the MRI findings with each clinical symptom or sign.

RESULTS

Thirty-one out of 88 patients with the initial diagnosis of IIH had MRI available and were included in the study. Significant correlations were observed between colour vision and amount of perineural fluid around the optic nerve on MRI (r = - 0.382; p = 0.004), disc assessment and intraocular optic nerve protrusion (r = 0.364; p = 0.004), disc assessment and perineural fluid around the optic nerve (r = 0.276; p = 0.033) and disc assessment and venous sinus stenosis (r = 0.351; p = 0.009).

CONCLUSION

Our study highlights correlations between imaging and clinical findings of IIH. MRI findings in IIH may be useful in ruling out ominous causes of intracranial pressure and risk stratifying ophthalmologic intervention and management of patients with headaches possibly due to IIH.

A cohort study of local excision followed by adjuvant therapy incorporating a contact X-ray brachytherapy boost instead of radical resection in 180 patients with rectal cancer

AIM

Recent data have suggested near-equivalent oncological results when treating early rectal cancer by local excision followed by radio- ± chemotherapy rather than salvage radical surgery. The aim of this retrospective study was to assess the use of contact X-ray brachytherapy within this paradigm.

METHOD

All patients had undergone local excision and were referred to our radiotherapy centre for treatment with contact X-ray brachytherapy. Postoperative (chemo)radiotherapy was also given in their local hospital in most cases. Variables assessed were local excision method, postoperative therapy received, follow-up duration, disease-free survival, salvage surgery and stoma-free survival.

RESULTS

In total, 180 patients with a median age of 70 (range 36-99) years were assessed. Following local excision, pT stages were pT1 = 131 (72%), pT2 = 44 (26%), pT3 = 5 (2%). All patients received contact X-ray brachytherapy boosting at our centre and, in addition, 110 received chemoradiotherapy and 60 received radiotherapy alone. After a median follow-up of 36 months (range 6-48), 169 patients (94%) remained free of local recurrence. Of the 11 patients with local recurrence (three isolated nodal), five underwent salvage abdominoperineal excision. Eight patients developed distant disease, of whom five underwent metastasis surgery. At last included follow-up 173 (96%) patients were free of all disease and 170 (94%) were stoma free.

CONCLUSIONS

Contact therapy can be offered in addition to external beam radio (±chemo) therapy instead of radical surgery as follow-on treatment after local excision of early rectal cancer. This combination can provide equivalent outcomes to radical surgery. The added value of contact therapy should be formally assessed in a clinical trial.

The relationship between sarcopenia and fragility fracture-a systematic review

Sarcopenia is a common geriatric syndrome characterized by progressive decrease of muscle mass and function leading to an increased risk of physical disability, poor quality of life, and mortality. Increasing evidence shows that sarcopenia is related with fragility fractures. This systematic review aimed to summarize the following: (1) the prevalence of sarcopenia in patients with fragility fracture and (2) the associated risk factors for fragility fracture in patients with sarcopenia. Literature search was conducted in PubMed and Cochrane databases. Studies with the prevalence of sarcopenia in elderly patients with fragility fracture and associated risk factors in patients with sarcopenia were included. A total of 15 papers were included, with 10 reporting sarcopenia prevalence, and 5 on fracture risk in patients with sarcopenia. The prevalence of sarcopenia after fracture ranged from 12.4 to 95% in males and 18.3 to 64% in females. The prevalence of sarcopenia in elderly patients with fragility fracture was high, especially in men. Two studies showed that sarcopenia was a risk factor for fragility fracture when associated with low bone mineral density (BMD) but only in men. Caution should be taken for male patients with sarcopenia and low BMD, which is related to significantly increased risk of fractures. There is a pressing need for further research on sarcopenia and its risk on fragility fracture to better understand the relationship, pathophysiology, and mechanisms, which may shed light on potential interventions to improve clinical outcomes.

Abstract P6-18-32: Profiling the early haematological dynamics and treatment modifications with palbociclib when used as first line treatment for ER-positive, HER2-negative metastatic breast cancer

Background: Palbociclib plus endocrine therapy (ET) significantly increases progression free survival compared to ET alone. Within PALOMA2 neutropenia was the most common AE and reason for dose reductions. No real data exists regarding dose reductions (DRs), dose interruptions (DIs), toxicities and benefits of palbociclib. Objective: To describe the early haematological dynamics, DRs/DIs with 1st line palbociclib in the context of a routine UK clinical practice. Methods: A prospective record was maintained of all patients with ER-positive, HER2-negative metastatic BC registered on the Pfizer patient programme at the Clatterbridge Cancer Centre NHS Foundation Trust. The clinical records of all patients commenced on treatment between April and December 2017 were reviewed, and clinico-pathological information, haematological data & toxicity data recorded. Data lock was 31st March 2018. Results: 48 patients received at least one cycle of treatment. The median age was 58, 29% (14/48) premenopausal & 71% (34/48) postmenopausal. 43% (21/48) had bone only disease with 42% (20/48) having visceral disease. The median number of cycles delivered 8 (range 2-11). DRs: 18/48 (38%) patients had a total of 21 DRs; 14/18 (78%) had 1 DR to 100mg; 1/18 (5%) 1 DR to 75mg; & 3/18 (17%) 2 DRs to 75mg. Reasons for DRs: 13 neutropenia, 2 leukopenia, 1 thrombocytopenia, 2 fatigue, 1 poor appetite, 1 sore mouth & 1 non-specially unwell. DIs: occurred in 24/48 patients (50%). Details of DRs/DIs by cycle will be presented. 85% (41 of 48) patients remain on treatment with 59% (24/41) on 125mg; 34% (14/41) on 100mg & 7% (3/41) on 75mg. FBC were available for 41/48 (85%) cases & dynamics considered over the first 6 cycles using FBC at the time of planned treatment delivery. Hb Baseline all patients (AP):129 (121 – 138), patients; patients with no dose reductions (NDR) 127 (123 – 139) & patient dose reduction (DR): 130 (118 – 136). Hb changes to cycles 2, 4 and 6 AP: 122 (115 – 131), 121 (116 – 127) and 125 (116 – 134); NDR:122 (110 - 135), 125 (117 - 127) and 131 (116 – 135); DR: 115 (112 - 120), 120 (115 - 124) and 122 (115 – 129). WCC Baseline AP: 6.8 (5.6 – 7.7); NDR: 7.2 (6.3 – 7.7); DR: 6.7 (5.2 – 7.7). WCC changes to cycles 2, 4 and 6 AP: 3.7 (2.9 – 4.4), 3.7 (3.1 – 4.4) and 3.3 (3 – 3.9); NDR: 3.5 (2.9 – 4.1), 3.6 (3.2 – 4.3) and 3.6 (3.1 – 4.1); DR: 2.1 (1.7 – 2.5), 4.3 (3 – 4.6) and 3.3 (2.8 – 3.5). ANC Baseline AP: 4.0 (3.2 – 5.1); NDR: 4.4 (3.4 – 5.0); DR: 3.6 (2.9 – 5.2). ANC changes to cycles 2, 4 and 6 AP: 1.5 (1.2 – 2.1), 1.7 (1.3 – 2.0) and 1.4 (1.2 – 1.9) NDR: 1.5 (1.1 – 2.1), 1.7 (1.4 – 2.0) and 1.3 (1.2 – 2.0); DR: 0.8 (0.6 – 0.8), 1.7 (1.2 – 2.3) and 1.4 (1.3 – 1.6). Plts Baseline AP: 298 (226 – 339), NDR: 252 (211 – 336); DR: 299 (253 – 339). Plt changes to cycles 2, 4 and 6 AP: 252 (198 – 310), 221 (186 – 259) and 200 (169 – 243). NDR: 249 (185 – 334), 229 (171 – 267) and 205 (177 – 263);DR: 208 (199 – 210), 216 (199 – 243) and 194 (162 -210). Conclusion: These initial real world data are consistent with the PALOMA2 data. Baseline WCC & ANC show no significant difference between NDR and DR cases. Updated data will be presented as well as outcome data for first time.

Citation Format: Bhojwani A, Flint H, Hall B, Wong H, Innes H, Cliff J, Ahmed E, Malik Z, O'Hagan J, Tolan S, Hall A, Hyatt K, Errington D, Alam F, Robson P, Thorp N, O'Reilly S, Law A, Cicconi S, Jackson R, Palmieri C. Profiling the early haematological dynamics and treatment modifications with palbociclib when used as first line treatment for ER-positive, HER2-negative metastatic 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 P6-18-32.

Abstract P6-13-04: Estrogen-alone based hormone replacement therapy (HRT) reduces breast cancer (BrCa) incidence and mortality whereas estrogen plus progestin Provera based HRT increases both BrCa incidence and BrCa mortality: A comparative analysis of Women's Health Initiative trials

OBJECTIVE: To quantitate breast cancer incidence (BrCa-I) and mortality (BrCa-M) outcome differences between the two Women's Health Initiative (WHI) HRT trials,1,2 the ratio of hazards was calculated for estrogen-alone based hormone replacement therapy (E-HRT) vs. placebo (P), and E + progestin Provera (ProgProv) combination HRT vs. P trials.

METHODS: Hazard ratios (HR) of BrCa-I and BrCa-M and 95% confidence intervals (CI) were obtained from both WHI HRT trials. Subsequently, to compare BrCa outcomes between E-HRT vs. E + ProgProv, the ratios of HRs between the trials (HR1/HR2) were estimated separately for i. BrCa-I all women, ii. BrCa-I low Gail score (Gail score <1.75*), and iii. BrCa-M. The 95% CI was derived through logarithmic transformation of the 95% CI originally reported.

RESULTS:

Outcome Comparison, the two WHI HRT randomized trials. Ratio of Hazards, BrCa Incidence and BrCa mortality E-HRT vs. P, HR1 (95% CI)E-HRT + ProgProv vs. P, HR2 (95% CI)HR1/HR2 (95% CI)pBrCa-I All Woman10.77 (0.62-0.95)1.25 (1.07-1.46)0.62 (0.47-0.80)0.0004BrCa-I Low Gail Score* (Gail score <1.75)10.65 (0.50-0.86)1.24 (1.01-1.51)0.53 (0.38-0.74)0.0002BrCa-M20.55 (0.33-0.92)1.44 (0.97-2.15)0.38 (0.20-0.75)0.004*Gail score <1.75; HRs calculated from Reference 1, Figure 3

CONCLUSIONS: Our calculations show that the different outcomes between the two WHI HRT trials, estimated as ratio of hazards, are highly significant on statistical basis, both for BrCa incidence and for BrCa mortality. These findings highlight the potential carcinogenic impact of ProgProv and the major public health benefits of HRT based on E alone.

REFERENCES:

1. Anderson GL, Chlebowski RT, Aragaki AK, et al. Conjugated equine oestrogen and breast cancer incidence and mortality in postmenopausal women with hysterectomy: extended follow-up of the Women's Health Initiative randomised placebo-controlled trial. The Lancet Oncology 2012;13:476-86.

2. Manson JE, Aragaki AK, Rossouw JE, et al. Menopausal Hormone Therapy and Long-term All-Cause and Cause-Specific Mortality: The Women's Health Initiative Randomized Trials. JAMA 2017;318:927-38.

Citation Format: Ragaz J, Qian H, Wong H, Wilson KS, Shakeraneh S, Spinelli JJ. Estrogen-alone based hormone replacement therapy (HRT) reduces breast cancer (BrCa) incidence and mortality whereas estrogen plus progestin Provera based HRT increases both BrCa incidence and BrCa mortality: A comparative analysis of Women's Health Initiative trials [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 P6-13-04.

Abstract P6-13-06: Estrogen-based hormone replacement [HRT] therapy is substantially more effective than tamoxifen in reducing breast cancer mortality and breast cancer case fatality ratio: Emergence of a new paradigm

OBJECTIVE: To compare, in the setting of breast cancer (BrCa) prevention, the impact of estrogen-based hormone replacement therapy (E-HRT) vs. tamoxifen (TAM) on breast cancer mortality (BrCa-M) and breast cancer case fatality ratio (BrCa-CFR), by analyzing data from the Women's Health Initiative Trial 2 (WHI HRT Trial 2, E-HRT vs. placebo [P])1 and the International Breast Cancer Intervention Study 1 (IBIS-1), TAM vs. P.2

METHODS: Hazard ratios (HR) and confidence intervals (CI) for BrCa incidence and mortality were extracted from the original WHI HRT Trial 2 and IBIS-1 trials.1,2 BrCa-CFRs were estimated by dividing the mortality HR by the incidence HR. Subsequently, to compare E-HRT vs. TAM outcomes, the ratios of HRs (HR1/HR2) between the two trials were estimated separately for BrCa-M and BrCa-CFR. The 95% CI was derived through logarithmic transformation of the 95% CI originally reported.

RESULTS:

Mortality and Case Fatality Outcomes: Impact of E-HRT versus TAM, expressed as ratio of HRs E-HRT vs. Placebo, HR1TAM vs. Placebo, HR2HR1/HR2pMortality0.55 (0.33-0.92)1.19 (0.68-2.10)0.46 (0.22-0.99)0.046Case Fatality0.70 (0.40-1.20)1.68 (0.93-3.01)0.42 (0.18-0.94)0.040

CONCLUSIONS: While acknowledging between-trial comparisons including eligibility differences, E-HRT yields significant reductions in BrCa mortality and case fatality as compared with TAM (54% and 58% respectively). These unexpected breast cancer mortality reductions represent major public health gains, additional to the already known superiority of E-HRT over TAM in terms of skeletal fracture rates and Alzheimer's dementia mortality reduction, and, in women entering menopause, also of cardiac and all-cause mortality reductions.

REFERENCES:

1. Manson JE, Aragaki AK, Rossouw JE, et al. Menopausal Hormone Therapy and Long-term All-Cause and Cause-Specific Mortality: The Women's Health Initiative Randomized Trials. JAMA 2017;318:927-38.

2. Cuzick J, Sestak I, Cawthorn S, et al. Tamoxifen for prevention of breast cancer: extended long-term follow-up of the IBIS-I breast cancer prevention trial. The Lancet Oncology 2015;16:67-75.

Citation Format: Ragaz J, Shakeraneh S, Qian H, Wilson KS, Wong H, Spinelli JJ. Estrogen-based hormone replacement [HRT] therapy is substantially more effective than tamoxifen in reducing breast cancer mortality and breast cancer case fatality ratio: Emergence of a new paradigm [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 P6-13-06.

Abstract P6-17-27: Real world experience of the medical and surgical management of HER2 positive early breast cancer treated with neoadjuvant trastuzumab and pertuzumab via the NHS England cancer drug fund

Background: Studies of neoadjuvant (NA) dual HER2 blockade with trastuzumab (T) and pertuzumab (P) in combination with chemotherapy (CT) for early breast cancer (BC) have reported pathological complete response (pCR) rates of 39 to 62%. These studies also report manageable toxicity with diarrhoea reported in up to 73% of cases. To date no real-world studies have explored the efficacy and toxicity of this treatment. The objective of this study was to describe the medical and surgical management of women treated with neoadjuvant T-P in combination with CT (NAT-P-CT). As well as to determine the efficacy toxicity of NAT-P-CT in the context of a routine UK NHS clinical practice.

Methods: Patients with HER2+ BC treated neoadjuvantly with T-P accessed via the NHS England Cancer Drug Fund (CDF) at the Clatterbridge Cancer Centre NHS Foundation Trust between October 2016 and January 2018 were retrospectively identified. Clinico-pathological information, treatment data, nurse led toxicity review and echocardiographic were reviewed. Data lock was 19th June 2018.

Results: 78 female patients were identified with a median age of 50 years (IQR: 44.4-60.2). At diagnosis: median tumour size 30mm (23.0-47.5mm), 62% (48/78) were LN positive & 56% (44/78) ER+. CT regimens: 81% (63/78) FEC-DHP of these 30% (19/63) switched to weekly paclitaxel (wP). or nab-paclitaxel; 5% (4/78); AC/EC-DHP; 9% (8/78) TCHP with 13% (1/8) switched to wP. At time of analysis, 88% (69/78) had undergone definitive surgery. Surgical details: Breast: 52% (36/69) mastectomy & 48% (33/69) WLE, Axillary management: 51% (35/69) axillary dissection (Ax Dx) & 49% (34/69) sentinel node biopsy (4 performed prior to NA treatment). 91% (32/35) of those undergoing Ax Dx were LN+ at presentation, of these 59% (19/32) had no evidence of axillary involvement at surgery. pCR rate (ypT0/is, N0) was 46% (32/69) [pCR by HR: ER+ 43% (21/49) & ER- 55% (11/20]. pCR for 20 patients switched to wP was 60% (12/20). 7% (5/69) achieved pCR in the breast alone (in these LN status ITCx1, micrometsx3 & macrometsx1). Of the 54% (37/69) with residual breast tumour median size was 13mm (1-22mm). Toxicity Data: Ejection fraction (EF) did not decline beyond 10% of baseline in any patients. Diarrhoea (any grade) occurred in 74% of cases, and CTCAE grade 3-4 toxicity occurring in >2% of patients: diarrhoea, fatigue, and infection. Updated analysis regarding pCR rate and toxicity, as well as initial outcome data will be presented.

Conclusion: These results (1) confirm the efficacy of NA T-P in a real world population; (2) support the use of NA wP; (3) indicate significant proportion of patients axilla are downstaged & (4) reveal diarrhoea rates in keeping with the literature. Currently, NHS England rules do not allow wP to be used routinely in NA setting with T-P this should be reviewed in light of these data and those of the BERENICE study. Measures to identify patients who can avoid axillary dissection as well as to mitigate diarrhoea should be considered.

Citation Format: Hall B, Bhojwani A, Innes H, Ahmed E, Cliff J, Malik Z, O'Hagan J, Tolan S, Hall A, Hayat K, Errington D, Alam F, Thorp N, Flint H, Law A, Wong H, O'Reilly S, Jackson R, Cicconi S, Palmieri C. Real world experience of the medical and surgical management of HER2 positive early breast cancer treated with neoadjuvant trastuzumab and pertuzumab via the NHS England cancer drug fund [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 P6-17-27.

Bioartificial Liver: Implanted Artificial Cells Microencapsulated Living Hepatocytes Increases Survival of Liver Failure Rats

Suspension of living hepatocytes were microencapsulated inside 300 micron mean diameter alginate artificial cells. The galactosamine fulminant hepatic failure rat model was used. 48 hours after the injection of galactosamine, grade II coma hepatic failure rats were divided into pairs. One of the pair was randomly chosen for the control group, and the other for the treated group. Each rat in the control group received one peritoneal injection of microcapsules containing no hepatocytes. Each rat in the treated group received one peritoneal injection of microcapsules containing hepatocytes. The survival of the treated group is significantly higher than the control group.

Expression of α1 adrenergic receptor subtypes by afferent fibers that innervate rat masseter muscle

Aims

In temporomandibular disorders sufferers, muscle pain is more severe in individuals who have undergone a traumatic stress. Why stress exacerbates masticatory muscle pain in these individuals is not known. One possibility is that under conditions of stress there is an interaction between the sympathetic and sensory nervous systems. This study investigated whether trigeminal ganglion neurons that innervate the masseter muscle express α1 adrenergic receptor subtypes to identify whether a direct interaction between the sympathetic and sensory nervous systems is feasible.

Methods

Masseter muscle ganglion neurons were identified by injection of the fluorescent dye fast blue into the masseter muscle of 4 Sprague Dawley rats (2 male, 2 female). Trigeminal ganglion sections were stained for α1a, α1b or α1d adrenergic receptors, as well as the transient receptor potential vanilloid 1 (TrpV1) receptor. Sections were examined with a Leica confocal microscope. The percent of masseter ganglion neurons expressing each receptor was calculated.

Results

Masseter muscle ganglion neurons expressed α1a(29 ± 9%), α1b (34 ± 4%) and α1d (19 ± 13%) adrenergic receptors. Expression of all three α1 receptor subtypes was higher in female rats than in male rats. Expression of α1b receptors was more commonly found on larger diameter masseter ganglion neurons. Overall 11±3% of masseter ganglion neurons expressed the TrpV1 receptor, which suggests they served a nociceptive function. The TrpV1 receptor was co-expressed by about ~10% of α1a and α1b receptor positive masseter ganglion neurons.

Conclusions

Afferent fibers that innervate the masseter muscle express all three α1 adrenergic receptor subtypes. Agonists at the α1 receptor have been previously shown to depolarize trigeminal ganglion neurons, which suggests that activation of these receptors on masseter muscle afferents would be excitatory. The expression of α1 receptors by putative nociceptors that innervate the masseter may permit a direct interaction between the sensory and sympathetic system that contributes to pain in this muscle.

Relationship between physical activity and hip pain in persons with and without cam or pincer morphology: a population-based case-control study

OBJECTIVES

The purpose of the study was to determine if physical activity (PA) is a risk factor for persistent or recurrent hip pain in young and middle-aged persons with and without radiographic findings of cam or pincer morphology (CPM).

METHODS

A population sample of persons aged 20-49 with (cases) and without (controls) hip pain in Metro Vancouver, Canada, was selected through random digit dialing (RDD). Self-reported PA was expressed as average energy expenditure (MET-hours) per year, over lifetime. CPM was defined as alpha angle >55°, lateral centre edge angle (LCE) >40°, or positive cross-over sign.

RESULTS

Data were obtained for 500 subjects, 269 cases and 231 controls. Prevalence of radiographic CPM was 49% in the cases and 44% in the controls. In a logistic regression model adjusted for age, gender and CPM, total lifetime PA, including occupational, domestic and recreational activities, was significantly associated with hip pain (Odds ratio (OR) 1.30 per 1000 MET-hours, 95% CI 1.15-1.38). The effect of total PA was observed in those with CPM (1.44, 1.17-1.78) and without CPM (1.23, 1.04-1.45). For domestic activities, the association was seen only in those with CPM (significant interaction). When PA was categorized into quartiles, higher levels of PA were associated with a greater risk of pain.

CONCLUSIONS

PA, as measured by average energy expenditure over lifetime is a risk factor for hip pain in young and middle-aged persons. For some activities, the risk is likely increased in persons with radiographic evidence of CPM.