Final results of the global and Asia cohorts of KAMILLA, a phase IIIB safety trial of trastuzumab emtansine in patients with HER2-positive advanced breast cancer

Background

KAMILLA is a single-arm safety study of trastuzumab emtansine (T-DM1) in patients with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (BC; NCT01702571). We report the final analysis of cohort 2 (Asia) within the context of published cohort 1 (Global) findings.

Methods

Patients had HER2-positive, locally advanced, or metastatic BC progressing after chemotherapy and anti-HER2 therapy or ≤6 months after adjuvant therapy. The primary objective was to further evaluate T-DM1 (3.6 mg/kg, administered intravenously every 3 weeks) safety/tolerability, including the following adverse events of primary interest (AEPIs): grade ≥3 AEPIs (hepatic events, allergic reactions, thrombocytopenia, hemorrhage events), all grade ≥3 treatment-related AEs, and all-grade pneumonitis.

Results

KAMILLA enrolled 2185 patients (cohort 1, n = 2003; cohort 2, n = 182) as of 31 July 2019. Of these, 2002 and 181 per cohort were treated and included in the safety population. Approximately 70% of patients had two or more previous treatment lines in the metastatic setting. Median T-DM1 exposure was 5.6 and 5.0 months per cohort; median follow-up was 20.6 and 15.1 months. The overall AEPI rate was higher in cohort 2 (93/181; 51.4%) versus cohort 1 (462/2002; 23.1%), mostly driven by a higher grade ≥3 thrombocytopenia rate in cohort 2. In cohort 2, grade ≥3 thrombocytopenia was not associated with grade ≥3 hemorrhagic events and most (128/138) fully resolved. Grade ≥3 treatment-related AEPI rates were 18.4% (cohort 1) and 48.6% (cohort 2), the latter mainly due to thrombocytopenia. Any-grade pneumonitis rates were 1.0% and 2.2%. No new safety signals were identified. Median (95% confidence interval) progression-free survival was 6.8 months (5.8-7.6 months) and 5.7 months (5.5-7.0 months) in cohorts 1 and 2, respectively; median overall survival was 27.2 months (25.5-28.7 months) and 29.5 months (21.1 months to non-estimable). In both cohorts, median progression-free survival and overall survival decreased with increasing prior therapy lines.

Conclusions

Cohort 2 results aligned with previous findings in Asian patients, supporting the manageable safety profile and use of T-DM1 in advanced BC.

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KAMILLA safety results for cohorts 1 (global; n = 2002) and 2 (Asia; n = 181) aligned with results from prior T-DM1 mBC trials.

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The overall rate of adverse events of primary interest (AEPIs) was higher in cohort 2 (51.4%) versus cohort 1 (23.1%).

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The higher AEPI rate was mostly due to a higher grade ≥3 thrombocytopenia event rate in cohort 2, most of which resolved.

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Median PFS and OS were similar for both cohorts, and decreased with increasing prior therapy lines.

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The manageable safety profile and efficacy of T-DM1 further support its favorable benefit/risk balance.

ReIMAGINE: a prostate cancer research consortium with added value through its patient and public involvement and engagement

BACKGROUND

ReIMAGINE aims to improve the current prostate specific antigen (PSA)/biopsy risk stratification for prostate cancer (PCa) and develop a new image-based method (with biomarkers) for diagnosing high/low risk PCa in men. ReIMAGINE's varied patient and public involvement (PPI) and engagement (PE) strategy maximises the impact of its scientific output by informing and shaping the different stages of research.

AIMS

Through including the voice of patients and the public, the ReIMAGINE Consortium aims to translate these different perspectives into the design and implementation process. This will improve the overall quality of the research by: reflecting the needs and priorities of patients and the public, ensuring methods and procedures are feasible and appropriate ensuring information is relevant and accessible to those being recruited to the study identifying dissemination channels relevant to patients/the public and developing outputs that are accessible to a lay audience With support from our patient/user groups, the ReIMAGINE Consortium aims to improve our ability to derive prognostic information and allocate men to the most appropriate and effective therapies, using a novel image-based risk stratification with investigation of non-imaging biomarkers.

FINDINGS

We have been working with patients and the public from initiation of the project to ensure that the research is relevant to men and their families. Our PPI Sub-Committee, led by a PCa patient, has been involved in our dissemination strategy, outreach activities, and study design recommendations. For example, the sub-committee have developed a variety of informative videos relevant and accessible to those being recruited, and organised multiple online research engagement events that are accessible to a lay audience. As quoted by one of the study participants, "the more we present the benefits and opportunities to patients and the public, the more research commitment we obtain, and the sooner critical clinical questions such as PCa diagnostics will be addressed".

Bradycardia associated with ALK inhibitors in the treatment of non-small cell lung cancers: a systematic review and meta-analysis

Introduction

Anaplastic Lymphoma Kinase (ALK) inhibitors represent a major therapeutic advance in the treatment of ALK-rearranged non-small cell lung cancer (NSCLC). Bradycardia was initially observed with crizotinib, the first ALK inhibitor. The risk of bradycardia and whether it differs among various generations of ALK inhibitors has not been systematically described.

Purpose

The primary objective of this systematic review is to compare the risk of bradycardia in patients who received an ALK inhibitor or standard chemotherapy for the treatment of NSCLC in randomized controlled trials.

Methods

We conducted a systematic literature search in MEDLINE, EMBASE, Cochrane Central, Web of Science, and Clinical Trials registry. We included randomized controlled trials that compared two different ALK inhibitors, or an ALK inhibitor with standard chemotherapies in patients with NSCLC. The primary outcome of interest was the number of bradycardia events. Because bradycardia was not systematically reported in many trials, we also documented reports of dizziness (as a potential symptom of bradycardia) in a secondary analysis.

Results

We identified 12 eligible studies including 2915 participants. Bradycardia was reported as a treatment-emergent adverse event in 9 trials; dizziness was reported in the remaining 3 trials. The type of bradycardia and use of heart rate-slowing medications were not documented in most studies. The incidence of bradycardia among 1080 individuals prescribed crizotinib in 8 trials was 13% (95% CI 9–17%) during a mean follow-up of 1.26 years. A meta-analysis of four trials that compared crizotinib with standard chemotherapies (Figure 1) showed a higher risk of bradycardia with crizotinib (RR 19.33; 95% CI 5.40–69.22). Newer generations of ALK inhibitors (alectinib, brigatinib and lorlatinib) showed similar rates of bradycardia compared to crizotinib (RR 0.51; 95% CI 0.21–1.26; Figure 2). Dizziness was more common in ALK inhibitors than standard chemotherapies (RR 1.83; 95% CI 1.38–2.42).

Conclusions

Our findings suggest that crizotinib is associated with a higher rate of bradycardia than standard chemotherapies, while no difference was found between crizotinib and newer generations of ALK inhibitors. The higher rate of dizziness in ALK inhibitors could represent a symptom of bradycardia. Further research is needed to evaluate the incidence and types of ALK inhibitor-associated bradycardia and its relationship with patient symptoms.

Funding Acknowledgement

Type of funding sources: None. Figure 2

P–111 Development of a flow cytometric assay for membrane lipid oxidation in human sperm

Study question

Is a commercially available lipid peroxidation assay sensitive enough to detect sperm lipid membrane damage and thus provide a novel indicator of male fertility status?

Summary answer

Provisional results demonstrate the novelty of creating a protocol to identify and quantify sperm lipid membrane damage and indicate possible insight into individual male fertility.

What is known already

Cytotoxic lipid aldehydes such as 4-hydroxynonenal (4HNE) created by the damaging effects of reactive oxygen species (ROS) have been studied extensively in sperm, as an indicator of male fertility. This is due to their connection with detrimental effects on sperm function such as morphology, acrosome reactions, motility and fertilization of the oocyte. Although literature states the mechanisms of damage caused to the lipid membrane of the sperm cell, there is no evidence of its quantification or usage as a commercial fertility indicator for human males.

Study design, size, duration

Since the assay is still being developed, there is no formal study size or duration. The goal of this pilot study is to determine whether a commercial lipid peroxidation assay can detect the difference between sperm with high levels of oxidative damage and control sperm cells. We used the remains of sperm samples initially collected for standard semen analysis, which were flash-frozen and then assayed with / without hydrogen peroxide treatment to induce oxidative damage.

Participants/materials, setting, methods

Frozen sperm from consenting donors (n = 21) were washed, optionally treated with hydrogen peroxide to induce oxidative damage, stained with a commercially available lipid peroxidation sensor (LPS, Abcam ab243377), and the resulting fluorescence quantitated by flow cytometry. Assay optimization varied the numbers of sperm input to the protocol, the concentration of the peroxidation sensor, the amount and duration of hydrogen peroxide treatment and the effect of paraformaldehyde (PFA) fixation of samples before or after staining.

Main results and the role of chance

Successful detection of lipid damage in control samples

We observed a significant difference at a p-value < 0.05 between untreated samples and all positive controls with hydrogen peroxide concentrations stronger than 500uM (p < 0.038) . This indicates that we can detect sperm bearing oxidative damage, and establishes the conditions required to make a positive control sample.

Establishment of assay parameters

Results indicate the concentration of sperm input to the protocol is not a significant factor for concentrations below 5 million/ml. Low concentration samples thus do not require further dilution before testing.

Correlation with DNA damage

A significant direct strong positive Pearson correlation coefficient (R = 0.93, p < 0.023) was found between samples with low DNA fragmentation index (DFI (%), measured by flow cytometric staining with acridine orange) and the LPS flow cytometric data (%).

Limitations, reasons for caution

As yet our data only addresses high level lipid damage induced by peroxide treatment. It remains to be established whether it is possible to detect endogenous LPO damage due to oxidative stress in semen. Future work will correlate our data with motility information and oxidative stress data (measured by MiOXSYS).

Wider implications of the findings: If we are able to develop a direct assay for sperm LPO, this will allow an additional avenue for testing patients with unexplained male infertility, which could in turn affect treatment choices and ART methodology. Improved diagnosis and treatment will potentially improve the lives of families with their fertility matters.

Trial registration number

Not applicable

Abstract P5-20-17: Safety of continuing chemotherapy in overt left ventricular dysfunction using antibodies to human epidermal growth factor receptor-2: A retrospective study

Introduction: Trastuzumab is a monoclonal antibody that targets the human epidermal growth factor receptor (HER)-2 and significantly improves survival in HER-2 positive early stage breast cancer. However, trastuzumab is also known to cause cardiotoxicity. Guidelines recommend withholding or discontinuing trastuzumab if left ventricular ejection fraction (LVEF) falls ≥15% from baseline, or to <50%, but there is little evidence to support this strategy. Additionally, premature discontinuation of trastuzumab may lead to poorer cancer outcomes. Trastuzumab cardiotoxicity is frequently reversible, and the use of angiotensin converting enzyme-inhibitors (ACE-I) and beta blockers is highly effective at treating impaired LVEF in other patient populations. We therefore hypothesize that it is safe to continue trastuzumab in patients with asymptomatic or mildly symptomatic fall in LVEF, when concomitantly treated with ACE-I and beta blockers.

Methods: In this retrospective chart review, we identified 18 consecutive patients with stage 1-3 HER-2 positive breast cancer patients who had a decline in LVEF meeting the criteria above to withhold trastuzumab, and who were referred to our cardio-oncology service from the beginning of 2015 to March 2017. These patients were offered and consented to receive ongoing trastuzumab accompanied by ACE-I and/or beta blocker. Data on patient demographics, cancer therapies, clinical features, LVEF, and cardiac medications were extracted from medical charts.

Results: Among the 18 patients identified, all were women, 12 (67%) were estrogen receptor positive, and 7 progesterone receptor positive (39%). 11 (61%) of patients had a left-sided breast cancer, 6 (33%) had right-sided breast cancer, and 1 (5%) had an unspecified side breast cancer. 17 (94%) of patients had previously undergone radiation therapy, and 4 (22%) had experienced a recurrence. 16 patients had received a prior anthracycline regimen (10 sequentially, 6 concurrently). The patients were treated with one or a combination of the following medications: carvedilol (n=13), ramipril (n=12), bisoprolol (n=1), candesartan (n=2), rosuvastatin (n=2), atorvastatin (n=2). The patients were followed up for an average of 7 months after starting cardiac therapy. Table 1 summarizes the mean±SD LVEF values over the follow up time period. All patient except one (94%) completed trastuzumab treatment successfully. This patient with concomitant moderate-severe mitral regurgitation was hospitalized for pulmonary edema. Trastuzumab was discontinued and LVEF has subsequently returned to normal values.

Table 1: LVEF progression from baseline to end of follow-upMean±SD LVEF at baseline57.59±5.49%Mean±SD LVEF on referral to cardio-oncology clinic50.75±4.76%Mean±SD LVEF at end of follow-up56.35±3.50%

Conclusion: Treating cardiac dysfunction related to trastuzumab in a cardio-oncology clinic, using beta blockers and ACE-I may enable completion of trastuzumab therapy. Randomized trials are necessary before it can be widely recommended, however findings from our experience suggest this may be a promising new treatment strategy.

Citation Format: Bharaj UK, Leong D, Dhesy-Thind S, Ellis P, Mukherjee S, Bordeleau L, Phillips C, Brown M, Kumar Tyagi N. Safety of continuing chemotherapy in overt left ventricular dysfunction using antibodies to human epidermal growth factor receptor-2: A retrospective study [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 P5-20-17.

Abstract P1-12-10: Safety and efficacy of trastuzumab emtansine (T-DM1) in 399 patients with central nervous system metastases: Exploratory subgroup analysis from the KAMILLA study

Introduction T-DM1 treatment significantly improved overall survival and had a lower incidence of grade ≥3 adverse events (AEs) vs capecitabine plus lapatinib in patients (pts) with HER2-positive advanced breast cancer (BC) in the EMILIA study, including pts with treated, asymptomatic CNS metastases (mets). KAMILLA is an ongoing, single-arm, open-label, phase 3b global safety study of T-DM1 in pts with HER2-positive locally-advanced or metastatic BC (target n=2220). In this interim analysis we describe clinical characteristics, safety, and efficacy in pts with stable CNS mets at baseline (BL).

Methods Eligible pts received prior HER2-directed therapy and chemotherapy and progressed on or after most recent treatment for advanced BC, or within 6 months of completing adjuvant therapy. Pts with asymptomatic CNS mets were eligible, including pts with stable CNS disease with prior radiation therapy. Pts received T-DM1 3.6 mg/kg every 3 weeks until unacceptable toxicity, withdrawal of consent, or disease progression. This exploratory analysis describes pts with BL CNS mets. Median progression-free survival (PFS) was estimated using the Kaplan-Meier method.

Results As of April 4, 2016, data were available for 2017 treated pts, of whom 399 (20%) had BL CNS mets, with a median follow-up of 33 months. Table 1 presents demographic and BL characteristics.

The incidence of AEs was similar between pts with and without BL CNS mets. Serious AEs (SAEs) occurred in 112 pts with BL CNS mets (28%) vs 311 of 1618 pts without BL CNS mets (19%), and the frequency of SAEs was comparable to that observed in EMILIA. However, nervous system disorder SAEs, such as seizure, epilepsy, and brain edema, occurred more frequently in pts with BL CNS mets (30 pts [8%]) vs 18 pts [1%] with no BL CNS mets.

Mean T-DM1 treatment duration was 8.0 months (median 8 cycles; range 1–55) in pts with BL CNS mets and 9.4 months (median 9 cycles; range 1–57) in pts with no BL CNS mets. Median PFS was 5.5 months in pts with BL CNS mets vs 7.9 months in pts with no BL CNS mets. A decrease in the size of brain target lesions was observed during T-DM1 treatment in 84 of 126 pts with measurable CNS lesions.

Table 1. BL characteristics CNS mets at BL (n=399)No BL CNS mets (n=1618)Median age, yrs (range)52 (28–83)55 (26–88)ECOG performance status, n (%)  0193 (48)929 (57)1174 (44)605 (37)232 (8)83 (5)Hormone receptor status, n (%)  ER and/or PR positive246 (62)992 (61)ER and PR negative149 (37)593 (37)Median time since initial BC diagnosis, yrs (range)4.8 (0–28)5.0 (0–53)Median time since first metastasis, yrs (range)2.4 (0–25)2.6 (0–35)Median number of prior therapies for metastatic BC (range)3 (0–>10)2 (0–>10)

Conclusions This subgroup analysis of KAMILLA is the largest reported cohort of pts with CNS mets treated with T-DM1. The overall safety profile of T-DM1 in pts with BL CNS mets was comparable to that of pts without CNS mets. As might be expected in pts with CNS disease, serious neurological AEs occurred more frequently in pts with BL CNS mets vs those without. Response to T-DM1 was seen in the CNS in pts with BL CNS mets, however, median PFS was lower in pts with BL CNS mets vs those without BL CNS mets.

Citation Format: Montemurro F, Ellis P, Delaloge S, Wuerstlein R, Anton A, Button P, Lindegger N, Barrios C. Safety and efficacy of trastuzumab emtansine (T-DM1) in 399 patients with central nervous system metastases: Exploratory subgroup analysis from the KAMILLA study [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 P1-12-10.

Firearm fatalities in Western Sydney 1994-2003

This study reviews firearm-related deaths (homicidal, suicidal and accidental) from 1994 to 2003 in the Western Sidney area, Australia, serviced by the Westmead Department of Forensic Medicine, in order to document the features of the cases and to assess the effect of the introduction of the NSW Firearms Act in 1996. There were 211 fatalities involving firearms (1.8% of all of the Coroner's cases for the period); firearm deaths were classified as homicide (75), suicide (134) or accidental (2). There was a clear peak of homicide deaths by firearm in the 20-29 age group, whereas the suicide peak was broad, spanning the ages 20-69 years. More suicides occurred at home than homicides and a higher proportion of suicides were by rifle than homicides, which favoured hand guns. Entry wounds in suicides mostly involved the head, with the chest being the commonest entry site in homicides. The only statistically significant trend was for an increase in the number of firearm-related suicides in males, comparing the number of deaths pre- and post-firearm law introduction. The study includes reports of two suicides by unusual weapons: a home-made pipe gun and a spear gun.

Extreme chromosomal instability forecasts improved outcome in ER-negative breast cancer: a prospective validation cohort study from the TACT trial

BACKGROUND

Chromosomal instability (CIN) has been shown to be associated with drug resistance and poor clinical outcome in several cancer types. However, in oestrogen receptor (ER)-negative breast cancer we have previously demonstrated that extreme CIN is associated with improved clinical outcome, consistent with a negative impact of CIN on tumour fitness and growth. The aim of this current study was to validate this finding using previously defined CIN thresholds in a much larger prospective cohort from a randomised, controlled, clinical trial.

PATIENTS AND METHODS

As a surrogate measurement of CIN, dual centromeric fluorescence in situ hybridisation was performed for both chromosomes 2 and 15 on 1173 tumours from the breast cancer TACT trial (CRUK01/001). Each tumour was scored manually and the mean percentage of cells deviating from the modal centromere number was used to define four CIN groups (MCD1-4), where tumours in the MCD4 group were defined as having extreme CIN.

RESULTS

In a multivariate analysis of disease-free survival, with a median follow-up of 91 months, increasing CIN was associated with improved outcome in patients with ER-negative cancer (P trend = 0.03). A similar pattern was seen in ER-negative/HER2-negative cancers (Ptrend = 0.007).

CONCLUSIONS

This prospective validation cohort study further substantiated the association between extreme CIN and improved outcome in ER-negative breast cancers. Identifying such patients with extreme CIN may help distinguish good from poor prognostic groups, and therefore support treatment and risk stratification in this aggressive breast cancer subtype.

Adjuvant taxanes and the development of breast cancer-related arm lymphoedema

BACKGROUND

Despite affecting approximately one-quarter of all patients undergoing axillary lymph node dissection, the pathophysiology of breast cancer-related lymphoedema (BCRL) remains poorly understood. More extensive locoregional treatment and higher body mass index have long been identified as major risk factors. This study aimed to identify risk factors for BCRL with a specific focus on the potential impact of chemotherapy on the risk of BCRL.

METHODS

This was a retrospective analysis of a cohort of consecutive patients with breast cancer treated at a major London regional teaching hospital between 1 January 2010 and 31 December 2012. All patients had node-positive disease and underwent axillary lymph node dissection. Data regarding tumour-, patient- and treatment-related characteristics were collected prospectively. The diagnosis of BCRL was based on both subjective and objective criteria. Multivariable Cox proportional hazards regression was used to assess the association between treatment and risk of BCRL.

RESULTS

Some 27.1 per cent of all patients (74 of 273) developed BCRL over the study period. Administration of taxanes showed a strong association with the development of BCRL, as 52 (33.5 per cent) of 155 patients who received taxanes developed BCRL. Multivariable Cox regression analysis demonstrated that patients who received taxanes were nearly three times more likely to develop BCRL than patients who had no chemotherapy (hazard ratio 2.82, 95 per cent c.i. 1.31 to 6.06). No such increase was observed when taxanes were administered in the neoadjuvant setting.

CONCLUSION

The present findings suggest that adjuvant taxanes play a key role in the development of BCRL after surgery. This may support the use of taxanes in a neoadjuvant rather than adjuvant setting.

Large-scale discovery of novel genetic causes of developmental disorders

Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.

Comparison of patient reported quality of life and impact of treatment side effects experienced with a taxane-containing regimen and standard anthracycline based chemotherapy for early breast cancer: 6 year results from the UK TACT trial (CRUK/01/001)

BACKGROUND

The TACT trial (CRUK/01/001) compared adjuvant sequential FEC-docetaxel (FEC-D) chemotherapy with standard anthracycline-based chemotherapy of similar duration in women with early breast cancer. Results at a median of 5 years suggested no improvement in disease-free survival with FEC-D. Given differing toxicity profiles of the regimens, the impact on quality of life (QL) was explored.

METHODS

Patients from 44 centres completed standardised QL questionnaires before chemotherapy, after cycles 4 and 8, at 9, 12, 18 and 24 months and at 6 years follow-up. Patient diaries assessed frequency, associated distress and impact on daily activity of 15 treatment related side effects.

FINDINGS

830 patients (415 FEC-D; 415 controls) contributed assessments during 0-24 months; 362 of whom participated again at 6 years. During chemotherapy, FEC-D impaired global health/QL and depression rates and significantly more QL domains than standard regimens. Novel diary card ratings highlighted significantly more distress and interference with daily activities due to FEC-D side effects compared with standard treatment. In both groups, most QL parameters returned to baseline levels by 2 years and were unchanged at 6 years.

INTERPRETATION

Within expected negative effects of chemotherapy on wide ranging QL domains FEC-D patients reported greater toxicity, disruption and distress during treatment with no improvement in disease outcome at 5 years than patients receiving standard anthracycline-based chemotherapy. Findings should inform future patients of relative costs and benefits of adjuvant chemotherapy.

The use of molecular imaging combined with genomic techniques to understand the heterogeneity in cancer metastasis

Tumour heterogeneity has, in recent times, come to play a vital role in how we understand and treat cancers; however, the clinical translation of this has lagged behind advances in research. Although significant advancements in oncological management have been made, personalized care remains an elusive goal. Inter- and intratumour heterogeneity, particularly in the clinical setting, has been difficult to quantify and therefore to treat. The histological quantification of heterogeneity of tumours can be a logistical and clinical challenge. The ability to examine not just the whole tumour but also all the molecular variations of metastatic disease in a patient is obviously difficult with current histological techniques. Advances in imaging techniques and novel applications, alongside our understanding of tumour heterogeneity, have opened up a plethora of non-invasive biomarker potential to examine tumours, their heterogeneity and the clinical translation. This review will focus on how various imaging methods that allow for quantification of metastatic tumour heterogeneity, along with the potential of developing imaging, integrated with other in vitro diagnostic approaches such as genomics and exosome analyses, have the potential role as a non-invasive biomarker for guiding the treatment algorithm.

Assessment of microtubule-associated protein (MAP)-Tau expression as a predictive and prognostic marker in TACT; a trial assessing substitution of sequential docetaxel for FEC as adjuvant chemotherapy for early breast cancer

The TACT trial is the largest study assessing the benefit of taxanes as part of adjuvant therapy for early breast cancer. The goal of this translational study was to clarify the predictive and prognostic value of Tau within the TACT trial. Tissue microarrays (TMA) were available from 3,610 patients. ER, PR, HER2 from the TACT trial and Tau protein expression was determined by immunohistochemistry on duplicate TMAs. Two parallel scoring systems were generated for Tau expression ('dichotomised' vs. 'combined' score). The positivity rate of Tau expression was 50 % in the trial population (n = 2,483). Tau expression correlated positively with ER (p < 0.001) and PR status (p < 0.001); but negatively with histological grade (p < 0.001) and HER2 status (p < 0.001). Analyses with either scoring systems for Tau expression demonstrated no significant interaction between Tau expression and efficacy of docetaxel. Contrary to the hypothesis that taxane benefit would be enriched in Tau negative/low patients, the only groups with a suggestion of a reduced event rate in the taxane group were the HER2-positive, Tau positive subgroups. Tau expression was seen to be a prognostic factor on univariate analysis associated with an improved DFS, independent of the treatment group (p < 0.001). It had no prognostic value in ER-negative tumours and the weak prognostic effect of Tau in ER-positive tumours (p = 0.02) diminished, when considering ER as an ordinal variable. On multivariable analyses, Tau had no prognostic value in either group. In addition, no significant interaction between Tau expression and benefit from docetaxel in patients within the PR-positive and negative subsets was seen. This is now the second large adjuvant study, and the first with quantitative analysis of ER and Tau expression, failing to show an association between Tau and taxane benefit with limited utility as a prognostic marker for Tau in ER-positive early breast cancer patients.

Abstract P5-01-01: Lymphoid tissue inducer cells: Identification of a novel immune cell within the breast tumour microenvironment and its role in promoting tumour cell invasion

Within breast cancers, trans-endothelial migration of tumour cells through lymphatic vessels is the first step to tumour dissemination and lympho-vascular invasion has been shown to stratify breast cancer phenotypes into distinct prognostic groups. The exact molecular mechanisms mediating tumor cell entry and persistence within the lymphatic system remain unclear. Lymphoid tissue inducer (LTi) cells are members of the emerging family of retinoic acid related orphan receptor (ROR)gt+ innate lymphoid cells (ILCs), and their interaction with stromal cells induces production by the stromal cells of VEGF-C and “lymphoid” chemokines, essential for lymphoid organogenesis. We hypothesized that tumour cells manipulate the normal processes that govern chemokine-dependent, trans-lymphatic migration of immune cells, including LTi cells; shaping its microenvironment. Results: We analyzed the expression of lymphoid chemokines genes (CXCL12, CXCL13, CCL19, CCL20 and CCL21) and their corresponding receptors (CXCR4, CXCR5, CCR6 and CCR7) within the METABRIC (Molecular Taxonomy of Breast Cancer International Consortium) Tissue Bank. An unsupervised hierarchical cluster analysis revealed co-expression of these genes, categorizing breast tumors as relatively high/low expressors. Tumors exhibiting relatively high expression of these genes were found to be enriched for “basal-like” breast cancers according to PAM50 intrinsic subtype assignments. Immunofluorescence of the primary tumour sections identified cells that were comparable in phenotype to LTi cells. In a blinded study, we observed that patients with high LTi counts within the tumour microenvironment were also likely to have a gene expression corresponding to high expression for the lymphoid chemokines. IHC for the lymphatic marker, podoplanin found that the LTi count correlated with both an increased lymphatic vessel density and tumor invasion into lymphatic vessels. Within the basal and HER2+ve subtypes, patients with more than 4 lymph nodes were found to exhibit higher numbers of intratumoural LTi cells. In vitro studies, alongside multi-photon in vivo imaging were performed to investigate the interaction between intra-tumoural LTi and mesenchymal stromal cells. CXCL13 was shown to be essential for LTi clustering around stromal cells in vitro, and, the administration of a blocking antibody in vivo delayed the onset of lymph node metastasis in a murine mammary tumour (4T1.2) model. CXCLl3 has been identified as having independent prognostic significance in breast cancer, but we and others report that breast cancer cell lines are not the source of CXCL13. We show that an increase in stromal CXCL13 concentration within the tumour microenvironment following LTi recruitment promotes an EMT phenotype in the 4T1.2 cancer cell line, possibly via activation of the RANKL/RANK axis promoting tumorigenesis. We report for the first time, the identification of LTi cells within the human breast cancer tumour microenvironment and propose a pivotal role for these cells, through stromal cell interactions in the tumour microenvironment, in facilitating lymphatic invasion of tumour cells by modulation of the local lymphoid chemokine profile.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-01-01.

Detailed molecular characterisation of acute myeloid leukaemia with a normal karyotype using targeted DNA capture

Advances in sequencing technologies are giving unprecedented insights into the spectrum of somatic mutations underlying acute myeloid leukaemia with a normal karyotype (AML-NK). It is clear that the prognosis of individual patients is strongly influenced by the combination of mutations in their leukaemia and that many leukaemias are composed of multiple subclones, with differential susceptibilities to treatment. Here, we describe a method, employing targeted capture coupled with next-generation sequencing and tailored bioinformatic analysis, for the simultaneous study of 24 genes recurrently mutated in AML-NK. Mutational analysis was performed using open source software and an in-house script (Mutation Identification and Analysis Software), which identified dominant clone mutations with 100% specificity. In each of seven cases of AML-NK studied, we identified and verified mutations in 2-4 genes in the main leukaemic clone. Additionally, high sequencing depth enabled us to identify putative subclonal mutations and detect leukaemia-specific mutations in DNA from remission marrow. Finally, we used normalised read depths to detect copy number changes and identified and subsequently verified a tandem duplication of exons 2-9 of MLL and at least one deletion involving PTEN. This methodology reliably detects sequence and copy number mutations, and can thus greatly facilitate the classification, clinical research, diagnosis and management of AML-NK.

Abstract P2-10-29: Time dependent breast cancer metastasis prediction using novel biological imaging, clinico-pathological and genomic data combined with Bayesian modeling to reduce over-fitting and improve on inter-cohort reproducibility

Background: Breast cancer heterogeneity demands that prognostic models must be biologically driven and recent clinical evidence indicates that future prognostic signatures need evaluation in the context of early versus late metastatic risk prediction. The aim of our work was to identify biologically validated quantitative imaging parameters with improved correlation to clinical outcome, and to address some of the remaining obstacles for a truly robust prognostic model in clinical use.

Method: We identified 4 seed proteins (ezrin/radixin/moesin-cofilin), along with several kinases as biologically relevant subnetwork of proteins that control tumor cell motility and metastasis. Patient-derived breast cancer tumour samples were used to perform a combination of imaging methods such as Fluoresecence lifetime imaging microscopy, automated segmentation and co-localisation intensity analysis. A complexity optimized Bayesian proportional hazard regression model was performed on a total of 419 breast cancer patients to validate time dependent predictions using traditional clinicopathological, genomic and our novel optical imaging-derived parameters. An independent dataset of 300 patient samples from the Leeds Institute of Molecular Medicine is currently being evaluated, representing a large cross centre validation of our integrated model.

Results: We demonstrate that the traditional gold standard clinico-pathological variables are poor predictors for patients that survive long periods, and that their predictive significance (in terms of hazard ratios) varies significantly between two temporal cohorts where the adjuvant treatments are vastly different. Moreover, we investigate the predictive accuracy of a combined imaging/clinicopathological model compared with genomic/clinicopathological models. We demonstrate how to reduce over-fitting to help improve the performance of prognostic models. Results of an integrated model combining genomic and imaging parameters are still awaited.

Discussion: We have produced the first optical imaging-derived multivariate tumour metastatic signature, which measures underlying key biological variables involved in regulating cancer cell motility. Using Bayesian proportional hazards regression in a time-dependent manner, we highlight the inadequacies of existing prediction tools and present a model combining the clinicopathological parameters with our imaging-based metastatic signature, as an integrative reproducible prognostic tool across different temporal cohorts.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-29.

Abstract P2-14-01: Fulvestrant vs exemestane for treatment of metastatic breast cancer in patients with acquired resistance to non-steroidal aromatase inhibitors – a meta-analysis of EFECT and SoFEA (CRUKE/03/021 & CRUK/09/007)

Background: Optimal endocrine treatment (trt) for post-menopausal women with ER+ advanced breast cancer (ABC) progressing on or following a non-steroidal (NS) aromatase inhibitor (AI) is unclear. The EFECT study showed no difference in efficacy between the steroidal antiestrogen fulvestrant (F) & steroidal AI exemestane (E) in this setting (HR = 0.96, 95%CI: 0.82, 1.13; p = 0.65). Pre-clinical data suggest F may be more effective in a low estrogen environment. SoFEA investigated F combined with anastrozole (F+A) in patients (pts) with acquired resistance to previous AI compared with F alone & F alone vs. E. The combination of F+A was no better than F (HR = 1.00, 95%CI: 0.83, 1.21; p = 0.98) nor F alone better than E (HR = 0.95, 95%CI: 0.79, 1.14; p = 0.56); the lack of added benefit for F+A is consistent with previous 1st-line studies that have assessed this combination versus A alone (FACT & SWOG-S0226).

Methods: SoFEA is a multi-center partially blinded randomized phase III study postmenopausal women were allocated to F plus A (F+A n=243), F plus placebo (n = 231) or E (n = 249). Similarly, EFECT is a randomized, double-blind, placebo controlled, multi-center phase III trial of F (n = 351) versus E (n = 342) in postmenopausal women (see table). However, given the differences in prior endocrine therapy/responsiveness within SoFEA & EFECT populations, an individual pt meta-analysis combining data from SoFEA & EFECT will be conducted enabling exploration of putative effects within specific pt subgroups to establish evidence in support, or not, of a pt subgroup sensitive to F at the dose used in these trials. Subgroups to be analysed include receptor status, visceral involvement, AI sensitivity, age, NSAI setting & time on NSAI.

Results: 723 pts (480 in F & E) were enrolled from 82 UK & 4 South Korean centers (03/2004-04/2010) in SoFEA. 693 pts were enrolled from 138 centers worldwide (08/2003-11/2005) in EFECT. Trt was well tolerated in both trials; serious adverse events were rare. The meta-analysis will be conducted in July 2012 & results presented.

Conclusion: Combining individual pt data from SoFEA & EFECT via meta-analysis will provide definitive clinical information on pt's response to F at the dose used in these studies, in particular whether certain pts with acquired resistance to NSAI do experience benefit of use of this antiestrogen as opposed to E.

Abstract P1-13-03: Mature analysis of UK Taxotere as Adjuvant Chemotherapy (TACT) trial (CRUK 01/001); effects of treatment and characterisation of patterns of breast cancer relapse

Introduction: TACT, an investigator-led study in 4162 women with node positive (N+ve) or high risk node negative (N-ve) early breast cancer (EBC), is the largest taxane trial unconfounded by treatment (trt) duration. At principal analysis, with 5 years follow-up (fup), no evidence of improved disease-free survival (DFS) was observed by switching to 4 cycles of docetaxel (D) after 4 cycles of FEC (Ellis, Lancet 2009). Results were provocative in suggesting differential effects according to ER & HER2 status. Longer fup provides opportunity to detect emergence of late trt effects overall & within phenotypic subgroups & explore patterns of recurrence, by tumor characteristics.

Patients & methods: TACT recruited women with histologically confirmed completely resected invasive EBC from 104 centers (UK (103), Belgium (1)) between 02/2001 & 07/2003. Centers chose FEC (600/60/600 mg/m2 q3wk × 8) or E-CMF (E 100mg/m2 q3wk × 4 → CMF 100mg/m2 PO d1-14 or 600mg/m2 IV d1&8/40/600 mg/m2 q4wk × 4) as their control, reflecting standard UK practice. Patients (pts) were randomized to FEC-D (FEC q3wk × 4 → D 100 mg/m2 q3wk × 4) or control. 2523 pts were from FEC centers (FEC = 1265: FEC-D = 1258) & 1639 from E-CMF centers (E-CMF = 824; FEC-D = 815). Endocrine therapy was given for 5 years. Few pts received HER2 directed therapy; 589 pts had unknown HER2 status. Median fup is now 97.5 months; this analysis updates DFS & overall survival in the ITT population. It also explores patterns of relapse by phenotypic & clinical characteristics. Analyses of trt effect are stratified by ER status due to issues of non-proportionality of hazard associated with length of fup.

Results: DFS events have been reported for 1329 pts (FEC-D=640, Control=689) giving an unadjusted hazard ratio (HR) & 95%CI (stratified by control regimen & ER status) of 0.93 (0.83, 1.03) overall; p = 0.16 in favor of FEC-D & for ER+ve/HER2-ve of 0.99 (0.84, 1.17), for ER+ve/HER2+ve) 0.97 (0.73, 1.30), for ER-ve/HER2+ve 0.74 (0.53, 1.03), & ER-ve/HER2-ve 0.93 (0.73, 1.17). 1017 patients have died (FEC-D=500, Control=517); unadjusted HR=0.98 (95%CI: 0.86, 1.10); p = 0.69 with intercurrent deaths (prior to distant relapse) reported for 80 pts (FEC-D=40, Control=40).

Annual event rates show different pattern of disease relapse by phenotypic subgroup

Variation in the annual unsatisfactory rates of selected pathogens and indicators in ready-to-eat food sampled from the point of sale or service in Wales, United Kingdom

The Welsh Food Microbiological Forum "shopping basket" survey is a long running, structured surveillance program examining ready-to-eat food randomly sampled from the point of sale or service in Wales, United Kingdom. The annual unsatisfactory rates for selected indicators and pathogens for 1998 through 2008 were examined. All the annual unsatisfactory rates for the selected pathogens were <0.5%, and no pattern with the annual rate was observed. There was also no discernible trend observed for the annual rates of Listeria spp. (not moncytogenes), with all rates <0.5%. However, there was a trend observed for Esherichia coli, with a decrease in rate between 1998 and 2003, rapid in the first few years, and then a gradual increase in rate up to 2008. It was concluded that there was no discernible pattern to the annual unsatisfactory rates for Listeria spp. (not monocytogenes), L. monocytogenes, Staphylococcus aureus, and Bacillus cereus, but that a definite trend had been observed for E. coli.

The relationship between vitamin D and chemotherapy-induced toxicity - a pilot study

BACKGROUND

There are anecdotal data that lower levels of vitamin D may be associated with increased levels of toxicity in individuals receiving chemotherapy; we therefore wished to investigate this further.

METHODS

From a cohort of over 11 000 individuals, we included those who had vitamin D levels (serum 1,25(OH)(2)D3) measured before and during chemotherapy. They were analysed for side effects correlating Chemotherapy Toxicity Criteria with vitamin D levels, normalising data for general markers of patient health including C-reactive protein and albumin.

RESULTS

A total of 241 (2% of the total cohort) individuals entered the toxicity analysis. We found no overall difference in toxicity effects experienced by patients depending on whether they were vitamin D depleted or had sufficient levels (P=0.78).

CONCLUSION

This pilot study suggests routine vitamin D measurement during treatment does not appear to be necessary in the management of chemotherapy-induced toxicity.

OT1-02-13: Cardiac Biomarkers on Trastuzumab (Cabot Trial): Determining the Cardiac Biomarker Profile in Breast Cancer Patients Receiving Adjuvant Trastuzumab Therapy

Background

Trastuzumab is a humanized anti-HER2 monoclonal antibody that has demonstrated a 50% reduction in the risk of HER2+ breast cancer recurrence. This benefit is at the risk of possible cardiac dysfunction. Detecting trastuzumab-related cardiotoxicity based on physical examination and assessment of left ventricular ejection fraction (LVEF) by serial echocardiography or multi gated acquisition (MUGA) scan, has low diagnostic sensitivity and low predictive power in detecting subclinical myocardial injury. There is interest in developing simple, non-invasive, and cost-effective tools for early identification of trastuzumab-related cardiotoxicity. Use of easily detectible cardiac biomarkers in blood, such as cardiac troponins (cTnT and cTnI) and natriuretic peptides (NPs), are being evaluated. Kavsak et al. have studied a high-sensitivity cTn (hs-cTn) assay that is 10-fold more sensitive, and may be able to identify evolving injury earlier when compared to the conventional cTn assays. B-type natriuretic peptide (BNP) has been established as an indicator for heart failure. Pro-BNP is secreted from the cardiac ventricles in response to increased pressure and volume and is divided into NT-pro-BNP and BNP. The longer half-life of NT-proBNP may make it a more accurate predictor of ventricular stress.

Trial design: This is a pilot single institution, prospective cohort study of 25 patients. Breast cancer patients will be seen at the Juravinski Cancer Centre, Hamilton, Canada. Biomarkers will be collected at baseline, then days 1 and 2 of every 21 day cycle for the first 3 months, then every 42 days for the next 3 months. LVEF will be measured at baseline and then every 3 months while on trastuzumab.

Eligibility criteria: Patients with stage I-III, HER2 positive (3+ by immunohistochemistry or FISH+) breast cancer receiving adjuvant trastuzumab therapy. Patients who have received prior trastuzumab therapy or are unable to provide informed consent will be excluded.

Specific aims: To determine the biological profile of cardiac biomarkers — cTnT, hs-cTn, and NT-proBNP — in patients on adjuvant trastuzumab; and, to determine if elevations in these biomarkers correlate with LVEF.

Statistical methods: A convenient sample size of 25 patients will be entered into this pilot study. The minimum of 20 patients is a requirement by the Clinical Laboratory Standards Institute (CLSI) to formally accept existing reference ranges for the cardiac biomarkers to be used in the HER2 breast cancer population (National Committee for Clinical Laboratory Standards (NCCLS)).

Present accrual and target accrual: 8 patients have enrolled to date.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT1-02-13.

Somatic SF3B1 mutation in myelodysplasia with ring sideroblasts

BACKGROUND

Myelodysplastic syndromes are a diverse and common group of chronic hematologic cancers. The identification of new genetic lesions could facilitate new diagnostic and therapeutic strategies.

METHODS

We used massively parallel sequencing technology to identify somatically acquired point mutations across all protein-coding exons in the genome in 9 patients with low-grade myelodysplasia. Targeted resequencing of the gene encoding RNA splicing factor 3B, subunit 1 (SF3B1), was also performed in a cohort of 2087 patients with myeloid or other cancers.

RESULTS

We identified 64 point mutations in the 9 patients. Recurrent somatically acquired mutations were identified in SF3B1. Follow-up revealed SF3B1 mutations in 72 of 354 patients (20%) with myelodysplastic syndromes, with particularly high frequency among patients whose disease was characterized by ring sideroblasts (53 of 82 [65%]). The gene was also mutated in 1 to 5% of patients with a variety of other tumor types. The observed mutations were less deleterious than was expected on the basis of chance, suggesting that the mutated protein retains structural integrity with altered function. SF3B1 mutations were associated with down-regulation of key gene networks, including core mitochondrial pathways. Clinically, patients with SF3B1 mutations had fewer cytopenias and longer event-free survival than patients without SF3B1 mutations.

CONCLUSIONS

Mutations in SF3B1 implicate abnormalities of messenger RNA splicing in the pathogenesis of myelodysplastic syndromes. (Funded by the Wellcome Trust and others.).

The cost-effectiveness of adjuvant chemotherapy for early breast cancer: A comparison of no chemotherapy and first, second, and third generation regimens for patients with differing prognoses

BACKGROUND

The risk of recurrence following surgery in women with early breast cancer varies, depending upon prognostic factors. Adjuvant chemotherapy reduces this risk; however, increasingly effective regimens are associated with higher costs and toxicity profiles, making it likely that different regimens may be cost-effective for women with differing prognoses. To investigate this we performed a cost-effectiveness analysis of four treatment strategies: (1) no chemotherapy, (2) chemotherapy using cyclophosphamide, methotrexate, and fluorouracil (CMF) (a first generation regimen), (3) chemotherapy using Epirubicin-CMF (E-CMF) or fluorouracil, epirubicin, and cyclophosphamide (FEC60) (a second generation regimens), and (4) chemotherapy with FEC60 followed by docetaxel (FEC-D) (a third generation regimen). These adjuvant chemotherapy regimens were used in three large UK-led randomised controlled trials (RCTs).

METHODS

A Markov model was used to simulate the natural progression of early breast cancer and the impact of chemotherapy on modifying this process. The probability of a first recurrent event within the model was estimated for women with different prognostic risk profiles using a parametric regression-based survival model incorporating established prognostic factors. Other probabilities, treatment effects, costs and quality of life weights were estimated primarily using data from the three UK-led RCTs, a meta-analysis of all relevant RCTs, and other published literature. The model predicted the lifetime costs, quality adjusted life years (QALYs) and cost-effectiveness of the four strategies for women with differing prognoses. Sensitivity analyses investigated the impact of uncertain parameters and model assumptions.

FINDINGS

For women with an average to high risk of recurrence (based upon prognostic factors and any other adjuvant therapies received), FEC-D appeared most cost-effective assuming a threshold of £20,000 per QALY for the National Health Service (NHS). For younger low risk women, E-CMF/FEC60 tended to be the optimal strategy and, for some older low risk women, the model suggested a policy of no chemotherapy was cost-effective. For no patient group was CMF chemotherapy the preferred option. Sensitivity analyses demonstrated cost-effectiveness results to be particularly sensitive to the treatment effect estimate for FEC-D and the future price of docetaxel.

INTERPRETATION

To our knowledge, this analysis is the first cost-effectiveness comparison of no chemotherapy, and first, second, and third generation adjuvant chemotherapy regimens for early breast cancer patients with differing prognoses. The results demonstrate the potential for different treatment strategies to be cost-effective for different types of patients. These findings may prove useful for policy makers attempting to formulate cost-effective treatment guidelines in the field of early breast cancer.

Using bevacizumab to treat metastatic cancer: UK consensus guidelines

Concise guidance is lacking for the use of bevacizumab by practicing oncologists. Eight oncologists with experience of bevacizumab were joined by a cardiologist interested in treating hypertension to develop practical guidelines for managing patients receiving bevacizumab, using available clinical data.

The 4th Annual Ontario Thoracic Cancer Conference at Niagara-on-the-Lake

The 4th annual Ontario Thoracic Cancer Conference at Niagara-on-the-Lake focused on the themes of innovations in the management of lung cancer, controversies in the management of esophageal cancer, and molecular targeted therapies in lung cancer. This conference summary highlights the presentations and provides clinicians with a referenced update on these topics.

The 4th Annual Ontario Thoracic Cancer Conference at Niagara-on-the-Lake

The 4th annual Ontario Thoracic Cancer Conference at Niagara-on-the-Lake focused on the themes of innovations in the management of lung cancer, controversies in the management of esophageal cancer, and molecular targeted therapies in lung cancer. This conference summary highlights the presentations and provides clinicians with a referenced update on these topics.

Correlation of PIK3CA mutation-associated gene expression signature (PIK3CA-GS) with deactivation of the PI3K pathway and with prognosis within the luminal-B ER+ breast cancers

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Background: The phosphathidylinositol-3-kinase (PI3K) signaling pathway is frequently deregulated in tumor biology and is an attractive target for cancer therapy. Our aim was to characterize the molecular and clinical outcome effects of PIK3CA mutations in breast cancer (BC). Methods: We analyzed 173 BC samples for PIK3CA mutations. Corresponding gene expression profiles were used to understand its effects on the PI3K pathway. We validated a PIK3CA-GS in 2 independent BC cohorts (n = 183) with known PIK3CA mutation status and evaluated its correlation with clinical outcome in 1748 BC samples stratified by treatment and subtype. Results: 26% of BCs had a PIK3CA mutation. Tumors with PIK3CA mutation demonstrated a distinct gene expression signature (p = 0.03 after 1000 perm). In 2 datasets it could discriminate PIK3CA mutation carriers from wild-type (ROC 0.68, 0.71, p = 0.001for both). However, the PIK3CA-GS was correlated with deactivation of the PI3K pathway probably through a negative feedback loop. This observation was supported by: 1) the PIK3CA-GS was significantly correlated with gene expression changes induced by PI3K inhibitors (Connectivity Map, Gene set enrichment analyses) and 2) the PIK3CA-GS was anti-correlated with a GS of PTEN loss (R = -0.3; Saal et al, 2007). Higher levels of the PIK3CA signature were observed in HER-2+ and estrogen receptor positive (ER+), luminal BC subtypes. Whilst there was no association with mutation status alone and prognosis, increasing expression of the PIK3CA-GS (suggesting deactivation) was significantly associated with better clinical outcome in both untreated (p = 0.04) and particularly ER+, luminal-B, tamoxifen only-treated (p = 0.004) BC. Multivariate analysis (HR: 0.4; 95%CI: 0.3–0.7; p = 0.002) confirmed that the PI3KCA-GS provided independent prognostic information. Conclusions: Paradoxically, the PIK3CA-GS correlates with inhibition of the PI3K pathway in ER+ BC and identifies a subgroup of luminal B BCs with a favorable outcome. The PIK3CA-GS may be a better indicator of PI3K pathway dysfunction than mutation status, potentially indicating patients who may benefit from combined endocrine therapy and PI3K inhibition.

No significant financial relationships to disclose.

A (59)Co NMR study to observe the effects of ball milling on small ferromagnetic cobalt particles

To demonstrate the potential of nuclear magnetic resonance (NMR) spectroscopy for investigating detailed structural properties in ferromagnetic materials, three different particle sized cobalt (Co) powders have been ball milled for 24h are accurately characterised by internal-field (59)Co NMR. The (59)Co NMR spectra show distinct resonance bands corresponding to the different Co sites, face-centred-cubic (fcc), hexagonal-close-packed (hcp) and stacking faults (sfs), in Co metal powders. The hcp+fcc-->hcp phase transition encouraged by ball-milling was observed and quantitative values for each Co environment were obtained.