Geographical Variation in Underlying Social Deprivation, Cardiovascular and Other Comorbidities in Patients with Potentially Curable Cancers in England: Results from a National Registry Dataset Analysis

AIMS

To describe the prevalence of cardiovascular disease (CVD), multiple comorbidities and social deprivation in patients with a potentially curable cancer in 20 English Cancer Alliances.

MATERIALS AND METHODS

This National Registry Dataset Analysis used national cancer registry data and CVD databases to describe rates of CVD, comorbidities and social deprivation in patients diagnosed with a potentially curable malignancy (stage I-III breast cancer, stage I-III colon cancer, stage I-III rectal cancer, stage I-III prostate cancer, stage I-IIIA non-small cell lung cancer, stage I-IV diffuse large B-cell lymphoma, stage I-IV Hodgkin lymphoma) between 2013 and 2018. Outcome measures included observation of CVD prevalence, other comorbidities (evaluated by the Charlson Comorbidity Index) and deprivation (using the Index of Multiple Deprivation) according to tumour site and allocation to Cancer Alliance. Patients were allocated to CVD prevalence tertiles (minimum: <33.3rd percentile; middle: 33.3rd to 66.6th percentile; maximum: >66.6th percentile).

RESULTS

In total, 634 240 patients with a potentially curable malignancy were eligible. The total CVD prevalence for all cancer sites varied between 13.4% (CVD n = 2058; 95% confidence interval 12.8, 13.9) and 19.6% (CVD n = 7818; 95% confidence interval 19.2, 20.0) between Cancer Alliances. CVD prevalence showed regional variation both for male (16-26%) and female patients (8-16%) towards higher CVD prevalence in northern Cancer Alliances. Similar variation was observed for social deprivation, with the proportion of cancer patients being identified as most deprived varying between 3.3% and 32.2%, depending on Cancer Alliance. The variation between Cancer Alliance for total comorbidities was much smaller.

CONCLUSION

Social deprivation, CVD and other comorbidities in patients with a potentially curable malignancy in England show significant regional variations, which may partly contribute to differences observed in treatments and outcomes.

1339 IMPROVING INPATIENT MANAGEMENT OF DELIRIUM IN A DISTRICT GENERAL HOSPITAL

Background

Delirium is a common clinical condition associated with increased morbidity and mortality, and prolonged hospital stay. Early detection is vital to improving management of the condition and improving outcomes.

Aims

Improve delirium detection using the 4AT screening tool as a validated approach; Improve delirium management across multiple domains using the PINCH ME approach; documented attempt at collateral history within 24 hours of recognition of delirium; obtain serological confusion screen in patients with recognised delirium. (100% each)

Method

Plan Do Study Act (PDSA) method was used to conduct this Quality Improvement (QI) project over 12 months. Data was obtained from paper and electronic records in the medical wards with regards to 'at risk patients' (i.e. over 65y, acutely unwell, background of cognitive impairment and/or acute fracture). The use of 4AT or alternative delirium screens from the emergency department (ED) and medical teams were noted. Assessment for pain, urinalysis, serological screens, bowel and nutrition review including MUST scores, medication reviews were looked for. Interventions included presentation and education at the medicine grand round, publishing a poster, and a PINCHME alert sticker for the medical notes to use at time of assessment. 2 PDSA cycles were completed and post sticker results obtained.

Results

Baseline data shows that collateral history was attempted for 70% patients - improved to 100% after sticker use. Use of validated screening test from 15% to 100% after sticker use. Nutrition assessment improved from 15% to 40%. Serological testing improved from 40% to 53%. 100% patients received a medication review after sticker use.

Conclusion

Introduction of PINCHME sticker serves as a prompt to ensure holistic management. Currently delirium management is clinician dependent as there is lack of formal delirium management pathway. Further plan includes involving nursing staff and 'delirium champions' to bring about a formal pathway for lasting change.

System resilience and neighbourhood action on social determinants of health inequalities: an English Case Study

AIMS

This article seeks to make the case for a new approach to understanding and nurturing resilience as a foundation for effective place-based co-produced local action on social and health inequalities.

METHODS

A narrative review of literature on community resilience from a public health perspective was conducted and a new concept of neighbourhood system resilience was developed. This then shaped the development of a practical programme of action research implemented in nine socio-economically disadvantaged neighbourhoods in North West England between 2014 and 2019. This Neighbourhood Resilience Programme (NRP) was evaluated using a mixed-method design comprising: (1) a longitudinal household survey, conducted in each of the Neighbourhoods For Learning (NFLs) and in nine comparator areas in two waves (2015/2016 and 2018/2019) and completed in each phase by approximately 3000 households; (2) reflexive journals kept by the academic team; and (3) semi-structured interviews on perceptions about the impacts of the programme with 41 participants in 2019.

RESULTS

A difference-in-difference analysis of household survey data showed a statistically significant increase of 7.5% (95% confidence interval (CI), 1.6 to 13.5) in the percentage of residents reporting that they felt able to influence local decision-making in the NFLs relative to the residents in comparator areas, but no effect attributable to the NRP in other evaluative measures. The analysis of participant interviews identified beneficial impacts of the NRP in five resilience domains: social connectivity, cultural coherence, local decision-making, economic activity, and the local environment.

CONCLUSION

Our findings support the need for a shift away from interventions that seek solely to enhance the resilience of lay communities to interventions that recognise resilience as a whole systems phenomenon. Systemic approaches to resilience can provide the underpinning foundation for effective co-produced local action on social and health inequalities, but they require intensive relational work by all participating system players.

Bridging the age gap in breast cancer: impact of omission of breast cancer surgery in older women with oestrogen receptor-positive early breast cancer on quality-of-life outcomes

BACKGROUND

Primary endocrine therapy may be an alternative treatment for less fit women with oestrogen receptor (ER)-positive breast cancer. This study compared quality-of-life (QoL) outcomes in older women treated with surgery or primary endocrine therapy.

METHODS

This was a multicentre, prospective, observational cohort study of surgery or primary endocrine therapy in women aged over 70 years with operable breast cancer. QoL was assessed using European Organisation for Research and Treatment of cancer QoL questionnaires QLQ-C30, -BR23, and -ELD14, and the EuroQol Five Dimensions 5L score at baseline, 6 weeks, and 6, 12, 18, and 24 months. Propensity score matching was used to adjust for baseline variation in health, fitness, and tumour stage.

RESULTS

The study recruited 3416 women (median age 77 (range 69-102) years) from 56 breast units. Of these, 2979 (87.2 per cent) had ER-positive breast cancer; 2354 women had surgery and 500 received primary endocrine therapy (125 were excluded from analysis due to inadequate data or non-standard therapy). Median follow-up was 52 months. The primary endocrine therapy group was older and less fit. Baseline QoL differed between the groups; the mean(s.d.) QLQ-C30 global health status score was 66.2(21.1) in patients who received primary endocrine therapy versus 77.1(17.8) among those who had surgery plus endocrine therapy. In the unmatched analysis, changes in QoL between 6 weeks and baseline were noted in several domains, but by 24 months most scores had returned to baseline levels. In the matched analysis, major surgery (mastectomy or axillary clearance) had a more pronounced adverse impact than primary endocrine therapy in several domains.

CONCLUSION

Adverse effects on QoL are seen in the first few months after surgery, but by 24 months these have largely resolved. Women considering surgery should be informed of these effects.

Bridging the age gap in breast cancer: cluster randomized trial of two decision support interventions for older women with operable breast cancer on quality of life, survival, decision quality, and treatment choices

BACKGROUND

Rates of surgery and adjuvant therapy for breast cancer vary widely between breast units. This may contribute to differences in survival. This cluster RCT evaluated the impact of decision support interventions (DESIs) for older women with breast cancer, to ascertain whether DESIs influenced quality of life, survival, decision quality, and treatment choice.

METHODS

A multicentre cluster RCT compared the use of two DESIs against usual care in treatment decision-making in older women (aged at least ≥70 years) with breast cancer. Each DESI comprised an online algorithm, booklet, and brief decision aid to inform choices between surgery plus adjuvant endocrine therapy versus primary endocrine therapy, and adjuvant chemotherapy versus no chemotherapy. The primary outcome was quality of life. Secondary outcomes included decision quality measures, survival, and treatment choice.

RESULTS

A total of 46 breast units were randomized (21 intervention, 25 usual care), recruiting 1339 women (670 intervention, 669 usual care). There was no significant difference in global quality of life at 6 months after the baseline assessment on intention-to-treat analysis (difference -0.20, 95 per cent confidence interval (C.I.) -2.69 to 2.29; P = 0.900). In women offered a choice of primary endocrine therapy versus surgery plus endocrine therapy, knowledge about treatments was greater in the intervention arm (94 versus 74 per cent; P = 0.003). Treatment choice was altered, with a primary endocrine therapy rate among women with oestrogen receptor-positive disease of 21.0 per cent in the intervention versus 15.4 per cent in usual-care sites (difference 5.5 (95 per cent C.I. 1.1 to 10.0) per cent; P = 0.029). The chemotherapy rate was 10.3 per cent at intervention versus 14.8 per cent at usual-care sites (difference -4.5 (C.I. -8.0 to 0) per cent; P = 0.013). Survival was similar in both arms.

CONCLUSION

The use of DESIs in older women increases knowledge of breast cancer treatment options, facilitates shared decision-making, and alters treatment selection. Trial registration numbers: EudraCT 2015-004220-61 (https://eudract.ema.europa.eu/), ISRCTN46099296 (http://www.controlled-trials.com).

Sample size determination in bioequivalence studies using statistical assurance

AIMS

Bioequivalence (BE) trials aim to demonstrate that the 90% confidence interval of the T/R-ratio of the pharmacokinetic metrics between two formulations (test [T] and reference [R]) of a drug is fully included in the acceptance interval [0.80, 1.25]. Traditionally, the sample size of BE trials is based on a power calculation based on the intrasubject variability coefficient of variation (CV) and the T/R-ratio of the metrics. Since the exact value of the T/R-ratio is not known prior to the trial, it is often assumed that the difference between the treatments does not exceed 5%. Hence, uncertainty about the T/R-ratio is expressed by using a fixed value for the sample size calculation. We propose to characterise the uncertainty about the T/R-ratio by a (normal) distribution for the log(T/R-ratio), with an assumed mean of  log θ = 0.00 (i.e. θ = 1.00) and a standard deviation σ_u , which quantifies the uncertainty. Evaluating this distribution leads to the statistical assurance of the BE trial.

METHODS

The assurance of a clinical trial can be derived by integrating the power over the distribution of the input parameters, in this case, the assumed distribution of the log(T/R)-ratio. Because it is an average power, the assurance can be interpreted as a measure of the probability of success that does not depend on a specific assumed value for the log(T/R)-ratio. The relationship between power and assurance will be analysed by comparing the numerical outcomes.

RESULTS

Using the assurance concept, values of the standard deviation for the distribution of potential log(T/R)-ratios can be chosen to reflect the magnitude of uncertainty. For most practical cases (i.e. when 0.95 ≤ θ ≤ 1.05), the sample size is not, or only slightly, changed when σ = |log(θ)|.

CONCLUSION

The advantage of deriving the assurance for BE trials is that uncertainty is directly expressed as a parameter of variability.

Adjuvant Chemotherapy for Breast Cancer in Older Women: An Analysis of Retrospective English Cancer Registration Data

AIMS

Adjuvant chemotherapy is recommended as a treatment for women with high recurrence risk early breast cancer. Older women are less likely to receive chemotherapy than younger women. This study investigated the impact of chemotherapy on breast cancer-specific survival in women aged 70 + years using English registry data.

MATERIALS AND METHODS

Cancer registration data were obtained from two English regions from 2002 to 2012 (n = 29 728). The impact of patient-level characteristics on the probability of receiving adjuvant chemotherapy was explored using logistic regression. Survival modelling was undertaken to show the effect of chemotherapy and age/health status on breast cancer-specific survival. Missing data were handled using multiple imputation.

RESULTS

In total, 11 735 surgically treated early breast cancer patients were identified. Use of adjuvant chemotherapy has increased over time. Younger age at diagnosis, increased nodal involvement, tumour size and grade, oestrogen receptor-negative or human epidermal growth factor receptor 2-positive disease were all associated with increased probability of receiving chemotherapy. Chemotherapy was associated with a significant reduction in the hazard of breast cancer-specific mortality in women with high risk cancer, after adjusting for patient-level characteristics (hazard ratio 0.74, 95% confidence interval 0.67-0.81).

DISCUSSION

Chemotherapy is associated with an improved breast cancer-specific survival in older women with early breast cancer at high risk of recurrence . Lower rates of chemotherapy use in older women may, therefore, contribute to inferior cancer outcomes. Decisions on potential benefits for individual patients should be made on the basis of life expectancy, treatment tolerance and patient preference.

Abstract P6-18-16: Ribociclib (RIBO) + letrozole (LET) in older patients with hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC): Preliminary subgroup results from the phase 3b CompLEEment-1 trial

Background: The cyclin-dependent kinase (CDK)4/6 inhibitor RIBO is approved in combination with an aromatase inhibitor (AI) for HR+, HER2– ABC in postmenopausal women with no prior therapy for ABC, based on the MONALEESA-2 trial (Hortobagyi et al. NEJM 2016). Although a high proportion of patients with HR+, HER2– ABC are &gt;65 years of age, older patients are often under-represented in clinical trials. Furthermore, treatment decisions may be complicated by comorbidities, functional status, and concurrent medications. Here, we report early safety results for patients ≥65 years of age enrolled in CompLEEment-1, an open-label, phase 3b trial evaluating RIBO+LET as first-line endocrine-based therapy in an expanded patient population.

Methods: Patients with HR+, HER2– ABC, ≤1 line of prior chemotherapy (CT), and no prior endocrine therapy for ABC received RIBO (600 mg/day, 3 weeks on/1 week off) + LET (2.5 mg/day); men and premenopausal women received concomitant goserelin (3.6-mg subcutaneous implant every 28 days). The primary outcome was safety and tolerability. A pre-planned interim analysis was conducted ˜15 months after first patient first visit.

Results: Of the first 1,008 patients enrolled who completed 56 days of follow-up or discontinued before the data cut-off date, 377 were ≥65 years of age. Of these, 157 (41.6%) were 65-&lt;70 years, 107 (28.4%) were 70-&lt;75 years, and 113 (30%) were ≥75 years. The majority of patients (94.4%) had an Eastern Cooperative Oncology Group performance status ≤1; 33.2% presented with stage IV disease at diagnosis; 9 patients were male. The most common sites of metastasis were bone (70.0%), lung (44.8%), and lymph nodes (29.7%). The most common all-grade adverse events (AEs) were neutropenia (58.4%), nausea (31.8%), and fatigue (24.1%). The most common grade 3/4 AEs were neutropenia (37.7%) and alanine aminotransferase increase (4.2%). QT prolongation events were mild (majority grade 1/2) and occurred in 6.1% of patients (0.5% grade 3/4). Dose reduction or interruption due to AEs occurred in 54.5% of patients; 6.9% of patients had AEs leading to treatment discontinuation. In the overall patient population, the most frequent grade 3/4 AEs were neutropenia (42.8%), leukopenia (3.4%), and increased alanine aminotransferase (2.9%); QT prolongation occurred in 5.4% of patients (0.5% grade 3/4).

Conclusions: Initial safety results from CompLEEment-1, from the first 56 days of follow-up, demonstrate the tolerability of RIBO+LET in older patients, consistent with the overall patient population. NCT02941926.

Citation Format: Ring A, Borstnar S, Ferreira A, Azim HA, Cottu P, Lu J, Martin M, Zamagni C, Beck JT, Zhou K, Wu J, Menon L, De Laurentiis M. Ribociclib (RIBO) + letrozole (LET) in older patients with hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC): Preliminary subgroup results from the phase 3b CompLEEment-1 trial [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 P6-18-16.

Abstract P1-15-08: Pathologic complete response rates following neoadjuvant systemic therapy in 794 patients with early breast cancer: The Royal Marsden experience

Background

The presence and extent of residual invasive cancer after neoadjuvant treatment (NACT) is a strong prognostic factor for risk of recurrence, especially in triple-negative (TN) and human epidermal growth factor receptor 2-positive (HER2+) breast cancer (BC). Recent advances in the standard-of-care NACT improved pathological complete response (pCR) rates in published clinical trials.

We evaluated the pCR rates, defined as ypT0-is ypN0, in our real-world BC population and in estrogen receptor-positive [ER+] HER2-, HER2+ and TN subgroups and their association with tumour, patients' characteristics and disease-free survival (DFS).

Methods

We retrospectively identified early BC patients receiving NACT between January 2013 and December 2017. Demographics, patient and disease characteristics, pathological responses, toxicities, dose delays and reductions were recorded. Simple statistics, Fisher's exact test, chi-squared method and Cox regression were used as appropriate.

Results

794 patients identified had median age of 50 years (range 24-87) and 93.9% (745 patients) ECOG performance status (PS) 0. 3.0% (24) had clinical stage I disease, 68.0% (540) stage II and 29.0% (230) stage III. 71.0% (564) had grade 3 disease and 91.8% (729) ductal histology. 33.7% (257) had ER+/HER2-, 25.8% (205) had TN and 38.0% (301) HER2+ disease. Overall, 6.8% (54) patients received platinum. 36.6% (291) patients had dose reductions and 24.3% (193) dose delays. Along with NACT, 51.6% (147) of the HER2+ patients received Trastuzumab and Pertuzumab and 48.4% (138) Trastuzumab alone.

pCR rate was 33.1% in the overall population and significantly different in ER+/HER2-, HER2+ and TN subgroups (12.84% versus 52.0% versus 28.43% respectively, p&lt;0.001). pCR was influenced by grade (1: 0%; 2: 24.3%; 3: 36.1%, p 0.005) and histology (ductal: 34.2%; lobular: 10.0%; mixed 25.0%; p 0.01). In the HER2+ subgroup, there was a trend for improved pCR rates for patients receiving Pertuzumab and Trastuzumab (57.0%) versus Trastuzumab alone (51.0%). No statistically significant differences were seen based on patients' characteristics including age and PS or in case of treatment dose reductions and delays. Early discontinuation of NACT was associated with lower pCR rates (20.5% vs 36.29%, p &lt;0.001).

Of interest, pCR rates remained consistent across the period 2013-2017 in the overall population. We observed a trend for improved pCR in the HER2+ (2013: 47.5%; 2014: 44.4%; 2015: 66.7%; 2016: 51.0%; 2017: 51.4%) and TN cohorts (2013: 23.5%; 2014: 25.0%; 2015: 25.0%; 2016: 33.3%; 2017: 34.1%) but not in the ER+/HER2- group.

Median DFS was 83.8 months (95% CI 62.0-NR) in the overall population. Although not reached in the TN cohort, median DFS was different according to disease subgroups (HER2+: 83.78 months; TN: NR; ER+/HER2-: 62.0 months, p &lt;0.0001).

Conclusions

In our analysis pCR rates are consistent with data published in literature and higher in HER2+ and TN disease. The impact of new agents had a relatively low impact on pCR rates in our overall population over the last 5 years, although they produced gradual improvements in the HER2+ and TN subgroups.

Citation Format: Battisti NML, True V, Chaabouni N, Chopra N, Lee K, Shepherd S, Shapira-Rotenberg T, Joshi R, Mohammed K, Allen M, Ring A. Pathologic complete response rates following neoadjuvant systemic therapy in 794 patients with early breast cancer: The Royal Marsden experience [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 P1-15-08.

Abstract P4-01-01: Molecular residual disease detection with circulating tumor DNA analysis predicts relapse in patients with early stage breast cancer

Background. Detection of circulating tumor DNA (ctDNA) after treatment of early stage breast cancer may identify molecular residual disease. In a prior proof-of-principle study we demonstrated that detection of ctDNA predicted relapse with high accuracy (Garcia-Murillas et al Science Trans Med 2015). We conducted an independent, prospective, multi-centre validation study.

Methods. In this validation study, a cohort of 170 early stage breast cancer patients were recruited from five hospitals into two prospective sample collection studies. Patients were scheduled to receive standard chemotherapy, surgery +/- radiotherapy, adjuvant endocrine therapy and HER2 antibodies as appropriate. Plasma samples were collected for ctDNA analysis at baseline, post-surgery, three monthly for the first year of follow-up, and six monthly thereafter and shipped to a central lab for processing. Using previously established criteria, tumor was sequenced to identify somatic mutations that were tracked by digital PCR in DNA extracted from 4mls of plasma at all available time points. Buffy coat DNA was analysed at all time-points to control for clonal haematopoesis of indeterminate potential (CHIP) detection. The primary endpoint was to compare invasive disease free survival between patients with and without detection of ctDNA after treatment. A combined analysis of this validation study, and the prior proof-of-principle study, was also conducted to analyse secondary endpoints.

Results. After tumor sequencing, 101 patients from the validation study had at least one mutation to track. At median 35.5 months follow-up, ctDNA was detected in plasma of 15.8% (16/101) patients. Detection of ctDNA strongly predicted relapse, hazard ratio 24.5 (95% CI 6.5 to 93.2, P&lt;0.001 time-dependent Cox model), and was predictive of relapse in all tumor subtypes.

In the combined analysis (N=144), lead-time between ctDNA detection and relapse was 10.7 months (95% CI 7.7-17.0). Six patients had a clinical relapse that was not detected by ctDNA prior to relapse. These patients had a distinct pattern of oligo-metastatic relapse, 3 patients with brain-only metastases (P=0.0068), 1 ovarian oligo-metastasis and 2 local disease recurrence. The level of ctDNA in baseline plasma, prior to treatment, was associated with tumor subtype, highest in triple negative breast cancer (P=0.0036).

Conclusion. Detection of ctDNA after treatment is associated with a high risk of future relapse in early-stage breast cancer. Prospective studies are required to assess the potential of molecular residual disease detection to guide adjuvant therapy.

Citation Format: Turner N, Garcia-Murillas I, Chopra N, Comino-Mendez I, Beaney M, Tovey H, Cutts R, Swift C, Kriplani D, Afentakis M, Hrebien S, Walsh G, Johnston S, Ring A, Russell S, Evans A, Skene A, Wheatley D, Dowsett M, Smith I. Molecular residual disease detection with circulating tumor DNA analysis predicts relapse in patients with early stage 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 P4-01-01.

Sternal Reconstruction with the Omental Flap—Acute and Late Complications, Predictors of Mortality, and Quality of Life

Background The omental flap is a reliable flap for the coverage of sternal defects. However, little is known about the predictors of mortality and the long-term outcome in such patients.

Methods We, therefore, performed a retrospective study from 2002 to 2013, including all patients who underwent sternal reconstruction with the omental flap.

Results A total of 50 patients were identified and mean follow-up was 3.8 years. Patient data was collected from the charts and 14 patients were available for telephone interviews. The majority of patients suffered from deep sternal wound infections. There was no complete flap loss and an overall success rate was 96%. In-hospital mortality was 14% and overall survival over follow-up was 50%. Significant predictors of mortality were age > 65, American Society of Anesthesiologists' status, defect size, prolonged ventilation, and the need for tracheotomy. Postoperative quality of life was reduced compared with other cohorts, especially with regard to bodily function. Pain was also a major problem for most patients along with herniation.

Conclusion The omental flap is a safe option even in patients with severe comorbidities. However, based on the data in this study, we would recommend the omental flap as a reserve option rather than first-line treatment for sternal defects.

Abstract OT1-06-03: The plasmaMATCH trial: A multiple parallel cohort, open-label, multi-centre phase II clinical trial of ctDNA screening to direct targeted therapies in patients with advanced breast cancer (CRUK/15/010)

Introduction

Circulating tumour DNA (ctDNA) is found in the plasma of over 90% of patients with advanced breast cancer (BC). Screening for the presence of mutations in ctDNA provides a current assessment of the genetic profile of the patient's recurrent BC. The plasmaMATCH trial is designed to assess the potential of ctDNA screening to direct targeted therapies in patients with advanced breast cancer.

Methods

plasmaMATCH is a multi-centre phase IIa umbrella trial platform of ctDNA screening and a therapeutic trial. The study will screen 1000 women with advanced breast cancer, who have received prior systemic treatment in the advanced setting, with digital PCR ctDNA assays for hotspot mutations in ESR1, HER2, AKT1, and PIK3CA, with HER2 copy number assessment, in a central laboratory. The study will recruit from up to 50 sites in the UK. Patients with mutations identified will enter the matching treatment cohort, ESR1 – extended dose fulvestrant 500mg every two weeks, HER2 – neratinib +/- fulvestrant, AKT1 – AZD5363 +/- fulvestrant.

Mutation prevalence is presented with corresponding exact 95% confidence intervals (CIs) both overall and excluding 14 patients who were known to have mutations from a prior screening program. Patients with more than one mutation are included once in each relevant row.

Results

We report the results of prospective ctDNA mutation testing in the first 92 patients. plasmaMATCH opened to recruitment on 15/12/2016. As of 08/06/2017, 120 patients have been registered for ctDNA screening from 7 UK centres, of which 92 have ctDNA screening results available:

plasmaMATCH ctDNA screening resultsMutationPrevalence (95% CI)Prevalence excluding 14 patients with known mutations (95% CI)ESR134/92: 37% (27%-48%)26/78: 33% (23%-45%)HER25/90: 6% (2%-12%)2/76: 3% (0%-9%)AKT17/92: 8% (3%-15%)4/78: 5% (1%-13%)PIK3CA*22/92: 24% (16%-34%)21/78: 27% (18%-38%)*No corresponding plasmaMATCH treatment cohort

14 patients had more than one mutation detected (10 ESR1+PIK3CA, 3 ESR1+AKT1, 1 ESR1+ +HER2+AKT1). ctDNA results were reported in a median of 8 working days.

Of the 40 patients with one or more actionable mutation, 15 have entered a cohort, 16 are being screened for entry into a cohort, 5 are currently receiving further systemic treatment prior to cohort entry and 4 will not enter a cohort. One additional patient has entered a treatment cohort on the basis of a mutation detected in an alternative tumour sequencing initiative.

Conclusions

plasmaMATCH ctDNA demonstrates the feasibility and accuracy of ctDNA testing as a screening tool for patients with advanced BC, with a high rate of subsequent recruitment into matching therapeutic trials.

Citation Format: Turner N, Bye H, Kernaghan S, Proszek P, Fribbens C, Moretti L, Morden J, Snowdon C, Macpherson I, Wardley A, Roylance R, Baird R, Bliss J, Ring A. The plasmaMATCH trial: A multiple parallel cohort, open-label, multi-centre phase II clinical trial of ctDNA screening to direct targeted therapies in patients with advanced breast cancer (CRUK/15/010) [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 OT1-06-03.

Abstract P2-01-04: The whole transcriptional landscape of circulating tumor cells compared to metastases in stage IV breast cancer

Background: Metastatic breast cancer (MBC) and the circulating cells (CTCs) leading to macrometastasis are inherently different than primary breast cancer, evolving under the selection pressure of systemic therapy. A better understanding of the tumor biology of CTCs compared to metastasis may shed light on treatment opportunities.

Methods: We performed whole transcriptome sequencing (RNA Seq) on fresh metastatic tumor biopsies (mets), CTCs, and peripheral blood (PB) from 21 newly diagnosed MBC patients. CTCs were harvested using the ANGLE Parsortix to isolate cells based on size and deformability. Data were analyzed for differential expression, pathways, single nucleotide variants (SNV), fusions, intrinsic subtype, and a CTC-mets shared gene signature was validated using data from The Cancer Genome Atlas (TCGA). Detailed clinical-pathological and treatment data was evaluated.

Results: CTCs as a group showed much stronger gene expression of oncogenes, stem cell genes, keratins and mesenchymal markers than did mets from the same patients. Matched patient comparisons for 66 potentially clinically actionable genes for 8/9 pathways showed no significant difference in gene expression targets between CTCs and mets on ANOVA, although fold-change did vary. Eight SNVs in the ESR1 gene (n=5 patients) and 5 SNVs in the HER2 gene (n=2 patients) were shared between CTCs and distant metastases.

Differential gene expression analysis identified a signature of 8870 genes that were statistically significantly correlated between CTCs and mets (FDR adjusted p&lt;0.05). Ingenuity pathway analysis was applied to the list of genes shared between CTCs and mets, with analysis of canonical pathways and upstream regulators revealing numerous oncogenes and breast cancer related genes. The top upstream regulators of CTCs-mets were beta-estradiol, progesterone, FOXA1, HNRPA2B1 and HNF1A. The top 50 genes of this CTC-mets shared signature were prognostic of worse overall survival in the TCGA breast cancer dataset (p&lt;0.001), which included 817 patients with a median follow-up of 59.5 months. Second time-point data for n=5 patients with subsequent PB draws 6 months after baseline is currently pending. Intrinsic subtyping of mets by either NanoString assays or RNA Seq were not concordant with intrinsic subtyping of CTCs by RNA Seq.

Four of 21 CTC samples showed strong whole transcriptome RPKM correlation with PB (R2)&gt;0.9, however, 3/21 CTC samples showed strong whole transcriptome RPKM correlation with mets (R2)&gt;0.8. The remainder showed low correlation with both. Coverage was 91.4X for CTCs, 140.2X for mets and 138.5X for PB.

Conclusions: We present the transcriptomic landscape of CTCs with comparison to metastases and peripheral blood all acquired prior to treatment of newly diagnosed Stage IV breast cancer. Multiple genes, including oncogenes and stem cell genes, were found with higher expression in CTCs versus metastases. When focusing on 66 known potentially clinically actionable genes in breast cancer, CTCs did not show significantly different patterns of expression than mets in terms of up-regulation versus down-regulation compared to PB. RNA Seq of CTCs may be utilized to identify molecular alterations that are potentially clinically actionable.

Citation Format: Ring A, Porras T, Campo D, Kaur P, Forte VA, Tripathy D, Lu J, Zada G, Wagle N, Wecsler JS, Lang JE. The whole transcriptional landscape of circulating tumor cells compared to metastases in stage IV 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 P2-01-04.

Abstract P2-02-17: Circulating tumor DNA analysis with ultra-high sensitivity sequencing in metastatic breast cancer

Introduction.

Circulating tumor DNA analysis has the potential to transform the clinical management of patients with breast cancer. We assessed the accuracy of ultra-high sensitivity ctDNA testing in patients with advanced breast cancer.

Methods.

From a prospective tissue collection study, we identified 25 patients with a contemporaneous metastatic tissue biopsy and plasma for ctDNA testing. Tumour DNA from the metastatic tissue biopsy was sequenced with a validated clinical hybrid capture panel, while plasma cell free DNA was sequenced with AVENIO ctDNA technology – a molecular barcoded duplex sequencing based on CAPPseq technology. Sample collection is on-going and results from the full concordance series will be presented at the conference.

Results.

Circulating tumour DNA was detectable in 87% (20/23) of patients, with at least one variant from tissue sequencing identified in plasma. There was overall high agreement between tissue and plasma sequencing. The sensitivity of plasma testing for variants identified in tumour, positive percent agreement, was 75% (24/32). Plasma testing revealed a diversity of sub-clonal mutations including polyclonal ESR1, polyclonal FGFR2 and FGFR3 mutations, rare KRAS mutations, and TSC1 and MSH2 inactivating mutations.

Conclusions.

Circulating tumour DNA testing with molecular barcoded duplex sequencing offers high sensitivity for tumour variant detection. The extent of sub-clonal resistance mutations identified emphasises the genetic diversity of advanced breast cancer.

Citation Format: Garcia-Murillas I, Proszek P, Fribbens C, Yuan L, Bye H, Hubank M, Jiang J, Yuang S, Palma J, Johnston S, Ring A, Turner N. Circulating tumor DNA analysis with ultra-high sensitivity sequencing in metastatic 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 P2-02-17.

Tracking evolution of aromatase inhibitor resistance with circulating tumour DNA analysis in metastatic breast cancer

Background

Selection of resistance mutations may play a major role in the development of endocrine resistance. ESR1 mutations are rare in primary breast cancer but have high prevalence in patients treated with aromatase inhibitors (AI) for advanced breast cancer. We investigated the evolution of genetic resistance to the first-line AI therapy using sequential ctDNA sampling in patients with advanced breast cancer.

Patients and methods

Eighty-three patients on the first-line AI therapy for metastatic breast cancer were enrolled in a prospective study. Plasma samples were collected every 3 months to disease progression and ctDNA analysed by digital droplet PCR and enhanced tagged-amplicon sequencing (eTAm-Seq). Mutations identified in progression samples by sequencing were tracked back through samples before progression to study the evolution of mutations on therapy. The frequency of novel mutations was validated in an independent cohort of available baseline plasma samples in the Study of Faslodex versus Exemestane with or without Arimidex (SoFEA) trial, which enrolled patients with prior sensitivity to AI.

Results

Of the 39 patients who progressed on the first-line AI, 56.4% (22/39) had ESR1 mutations detectable at progression, which were polyclonal in 40.9% (9/22) patients. In serial tracking, ESR1 mutations were detectable median 6.7 months (95% confidence interval 3.7-NA) before clinical progression. Utilising eTAm-Seq ctDNA sequencing of progression plasma, ESR1 mutations were demonstrated to be sub-clonal in 72.2% (13/18) patients. Mutations in RAS genes were identified in 15.4% (6/39) of progressing patients (4 KRAS, 1 HRAS, 1 NRAS). In SoFEA, KRAS mutations were detected in 21.2% (24/113) patients although there was no evidence that KRAS mutation status was prognostic for progression free or overall survival.

Conclusions

Cancers progressing on the first-line AI show high levels of genetic heterogeneity, with frequent sub-clonal mutations. Sub-clonal KRAS mutations are found at high frequency. The genetic diversity of AI resistant cancers may limit subsequent targeted therapy approaches.

Comprehensive geriatric assessment in 326 older women with early breast cancer

Background:

One-third of new early breast cancer diagnoses occur in women over 70 years old. However, older women are less likely to receive radical curative treatments. This study prospectively evaluated a cohort of older women using a Comprehensive Geriatric Assessment (CGA) to determine whether fitness explained the apparent under-treatment in this patient group.

Methods:

In this multi-centre prospective study, patients aged ⩾70 years with Stages I–III breast cancer underwent a pretreatment baseline CGA consisting of eight assessment tools. Patients were defined as ‘fit’ if they had normal score in seven out of eight of the assessment tools. ‘High risk’ patients were defined as those with grade 3, ER negative, HER2 positive, or node positive breast cancer.

Results:

Data on 326 patients were available for full analysis. The median age was 77 years. In all, 182 (56%) of the total population were defined as high risk, with 49%, 61% and 53% of those in the 70–74, 75–84 and ⩾85 years age groups respectively having high risk tumours. A total of 301 patients had sufficient CGA records of whom 131 (44%) were reported as fit, with 34%, 54% and 12% of them in the 70–74, 75–84 and ⩾85 years age groups respectively. More fit than unfit patients underwent primary breast surgery (100% vs 91%, P=0.0002), axillary surgery (92% vs 84%, P=0.0340), and adjuvant chemotherapy for high-risk disease (51% vs 20%, P=0.0001). Rates of adjuvant radiotherapy after wide local excision were not significantly different (88% vs 90% respectively, P=0.8195).

Conclusions:

In this study, all women ⩾70 years deemed fit by CGA underwent primary surgery. Nearly 50% of fit women with high-risk disease did not receive adjuvant chemotherapy suggesting under treatment in this group.

Abstract P3-07-10: The role of CBP/FOXM1 in triple negative breast cancer

Background: Accurate assessment of prognostic and predictive biomarkers (estrogen receptor, progesterone receptor, HER2) plays a critical role in the clinical management of breast cancer. Triple negative breast cancers (TNBCs) lack the expression of all three targets, and no targetable molecular pathways have been identified to date. Hence, TNBCs are treated with non-targeted, cytotoxic chemotherapeutic agents (e.g. paclitaxel), and are characterized by high rates of drug resistance and metastatic relapse. CREB binding protein (CBP) has been implicated in cell growth and malignant transformation in various cancers. CBP is an important co-activator in the β-catenin driven transcription, including the Wnt signaling pathway, which has been implicated in TNBC biology. The Kahn lab has developed a specific CBP-binding small molecule inhibitor, ICG-001. We hypothesized that CBP-signaling plays an important role in TNBC biology and may provide a novel therapeutic target.

Methods: We used TOP-flash assay to quantify Wnt signaling activity in TNBC. ICG-001 treatment combined with RNA Seq was used to characterize the role of CBP in TNBC cell line models. Co-immunoprecipitation (CoIP), protein and gene expression studies, as well as gene knock-down were used for validation. In vitro drug resistant cell line models as well as in vivo cell line (n=40 mice) and patient derived xenografts (PDX) in NOD scid gamma mouse models (2 patients, n=40 mice per patient) (treatmenent groups: control, paclitaxel, ICG-001, paclitaxel+ICG-001, n=5 mice per condition, primary and secondary implantation) were used to establish the effect of CBP inhibition via ICG-001 in TNBC on drug resistance and metastasis. We used the TCGA breast cancer data set to substantiate the experimental results.

Results: We demonstrated that gene expression in TNBC is CBP, but not Wnt signaling dependent, and can be disrupted via ICG-001. RNA Seq analysis of TNBC cells treated with ICG-001 revealed Forkhead box M1 (FOXM1) as a potential downstream regulator. CoIP demonstrated that CBP binding to the FOXM1/β-catenin transcriptional complex. Treatment with ICG-001 revealed that CBP/FOXM1 binding, but not FOXM1/ β-catenin binding, is critical for FOXM1 expression. The PDX mouse models demonstrated that FOXM1 expression correlates with response to chemotherapy and disease recurrence in vivo. Treatment with ICG-001 sensitized FOXM1 high tumors to chemotherapeutic treatment and statistically significantly reduced tumor growth in serial transplantation experiments. Comparison of clinical data with FOXM1 expression in tumor samples from patients indicated that high levels of FOXM1 were associated with disease relapse and poor survival outcomes.

Conclusion: CBP/FOXM1 binding is critical for FOXM1 expression. Targeting CBP/FOXM1 binding via ICG-001 could provide a novel therapeutic strategy in TNBC. The use of clinically annotated tissue microarrays containing a total of 430 breast tissue cores (51 TNBC cases) is currently pending to correlate nuclear protein expression of CBP and FOXM1 with survival outcomes in TNBC. FOXM1 and CBP could potentially be of value as predictive biomarkers in TNBC. These results could provide a clinical-translational rational for patient stratification based on CBP and FOXM1 expression for clinical trials exploring the therapeutic potential of FOXM1 inhibition via ICG-001 in combination with chemotherapy.

Citation Format: Ring A, Nguyen C, Lenz H-J, Tripathy D, Lang JE, Kahn M. The role of CBP/FOXM1 in triple negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-07-10.

Abstract P1-01-11: Something from nothing? The case for quality control in liquid biopsy studies

Background: Circulating tumor cells (CTCs) as a liquid biopsy strategy are currently being studied as a surrogate biomarker that may reflect metastatic tumor biology. Given the rarity of CTCs, target enrichment is commonly used to profile the gene signatures of valuable clinical samples to evaluate for multiplexed gene panels of interest. The aim of our study was to evaluate if the NanoString PAM50 could be used for accurate gene expression profiling of CTCs and controls using the research-use-only probeset.

Methods: We collected two 7.5mL EDTA tubes of blood from 12 healthy female volunteers. CTC assays were performed using the ANGLE Parsortix system as a microfluidics filter that separates cells based on size and deformability. The cell lines Hs578T (basal-like) and SK-BR-3 (HER2 amplified) were used to spike 20 cells into n=6 blood tubes per cell line (termed spiked samples). N=12 7.5mL tubes of blood (termed unspiked samples) and n=12 spiked samples were processed using Parsortix for CTC harvesting and lysis using a 10 micron cassette. From each lysate, 5uL was taken for cDNA amplification, multiple target enrichment for 14 cycles, followed by NanoString PAM50 assays. From each of the 12 peripheral blood (PB) samples, we extracted RNA and used 100ng for NanoString PAM50 assays. For cell line controls, 100ng of Hs578T or SK-BR-3 were subjected to NanoString Assays.

Results: Low PAM50 gene expression was observed in all 12 PB samples. Unspiked PB harvested from the CTC assay showed a higher level of PAM50 gene expression compared to PB, suggesting that the target enrichment amplification produces false positive detection of expected breast cancer related transcripts. On ANOVA testing, 10/12 (83%) of unspiked, sorted, target enriched samples had significant differential expression (p&lt;0.0001) of the mean log normalized counts for the PAM50 genes compared to PB.

In spiked experiments using n=20 cells in 7.5mL of PB, sorted Hs578T were found to be triple negative in only 3/6 (50%) while sorted SK-BR-3 were found to be HER2 positive in only 3/6 (50%). On ANOVA testing, the spiked/sorted and bulk were found to have a difference among the mean log normalized counts for the PAM50 genes across all samples for both cell lines (p&lt;0.0001). However, 3/6 (50%) samples had a difference in mean PAM50 gene expression when compared to bulk Hs578t on multiple comparison testing while 2/6 (33%) were statistically significantly different when comparing spiked, sorted SK-BR-3 versus bulk cell line.

Conclusions: Unspiked blood processed via a CTC assay and subjected to target enrichment showed high expression of genes in the NanoString PAM50 assay, likely due to amplification bias. When working with enriched but not ultra-pure CTC samples, amplified gene expression of background leukocytes may influence read counts. This is important to consider in assays that enrich for CTCs but retain a leukocyte background. Further studies will address the effect of the CTC assay procedure and number of leukocytes on accuracy of gene expression of rare CTC mimics. This study emphasizes the importance of selecting genes that are not expressed in PB or performing background subtraction or normalization as strategies for accurate gene expression profiling of CTCs.

Citation Format: Porras TB, Bains PK, Ring A, Carrasco S, Forte V, Punj V, Lang JE. Something from nothing? The case for quality control in liquid biopsy studies [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-01-11.