Barbara Brouwers

Vitamin D status at breast cancer diagnosis: correlation with tumor characteristics, disease outcome, and genetic determinants of vitamin D insufficiency

We correlated serum 25-hydroxyvitamin D(3) (25OHD) levels with tumor characteristics and clinical disease outcome in breast cancer patients and assessed the impact of genetic determinants of vitamin D insufficiency. We collected serum from 1800 early breast cancer patients at diagnosis, measured 25OHD by radioimmunoassay (RIA), and determined genetic variants in vitamin D-related genes by Sequenom. Multivariable regression models were used to correlate 25OHD levels with tumor characteristics. Cox proportional hazard models were used to assess overall survival (OS), disease-specific survival (DSS), and disease-free interval (DFI). Lower 25OHD serum levels significantly correlated with larger tumor size at diagnosis (P = 0.0063) but not with lymph node invasion, receptor status, or tumor grade. Genetic variants in 25-hydroxylase (CYP2R1) and vitamin D-binding (DBP) protein significantly determined serum 25OHD levels but did not affect the observed association between serum 25OHD and tumor size. High serum 25OHD (>30 ng/mL) at diagnosis significantly correlated with improved OS (P = 0.0101) and DSS (P = 0.0192) and additionally had a modest effect on DFI, which only became apparent after at least 3 years of follow-up. When considering menopausal status, serum 25OHD had a strong impact on breast cancer-specific outcome in postmenopausal patients [hazards ratios for 25OHD >30 ng/mL versus ≤30 ng/mL were 0.15 (P = 0.0097) and 0.43 (P = 0.0172) for DSS and DFI, respectively], whereas no association could be demonstrated in premenopausal patients. In conclusion, high vitamin D levels at early breast cancer diagnosis correlate with lower tumor size and better OS, and improve breast cancer-specific outcome, especially in postmenopausal patients.

Circulating MicroRNAs as easy-to-measure aging biomarkers in older breast cancer patients: correlation with chronological age but not with fitness/frailty status.

Circulating microRNAs (miRNAs) hold great promise as easily accessible biomarkers for diverse (patho)physiological processes, including aging. We have compared miRNA expression profiles in cell-free blood from older versus young breast cancer patients, in order to identify “aging miRNAs” that can be used in the future to monitor the impact of chemotherapy on the patient’s biological age. First, we assessed 175 miRNAs that may possibly be present in serum/plasma in an exploratory screening in 10 young and 10 older patients. The top-15 ranking miRNAs showing differential expression between young and older subjects were further investigated in an independent cohort consisting of another 10 young and 20 older subjects. Plasma levels of miR-20a-3p, miR-30b-5p, miR106b, miR191 and miR-301a were confirmed to show significant age-related decreases (all p≤0.004). The remaining miRNAs included in the validation study (miR-21, miR-210, miR-320b, miR-378, miR-423-5p, let-7d, miR-140-5p, miR-200c, miR-374a, miR376a) all showed similar trends as observed in the exploratory screening but these differences did not reach statistical significance. Interestingly, the age-associated miRNAs did not show differential expression between fit/healthy and non-fit/frail subjects within the older breast cancer cohort of the validation study and thus merit further investigation as true aging markers that not merely reflect frailty.

Genetic variability in the multidrug resistance associated protein-1 (ABCC1/MRP1) predicts hematological toxicity in breast cancer patients receiving (neo-)adjuvant chemotherapy with 5-fluorouracil, epirubicin and cyclophosphamide (FEC)

BACKGROUND To assess the impact of single-nucleotide polymorphisms (SNPs) on predefined severe adverse events in breast cancer (BC) patients receiving (neo-)adjuvant 5-fluorouracil (FU), epirubicin and cyclophosphamide (FEC) chemotherapy. PATIENTS AND METHODS Twenty-six SNPs in 16 genes of interest, including the drug transporter gene ABCC1/MRP1, were selected based on a literature survey. An additional 33 SNPs were selected in these genes, as well as in 12 other genes known to be involved in the metabolism of the studied chemotherapeutics. One thousand and twelve female patients treated between 2000 and 2010 with 3-6 cycles of (neo-)adjuvant FEC were genotyped for these SNPs using Sequenom MassARRAY. Severe adverse events were evaluated through an electronic chart review for febrile neutropenia (FN, primary end point), FN first cycle, prolonged grade 4 or deep (<100/µl) neutropenia, anemia grade 3-4, thrombocytopenia grade 3-4 and non-hematological grade 3-4 events (secondary end points). RESULTS Carriers of the rs4148350 variant T-allele in ABCC1/MRP1 were associated with FN relative to homozygous carriers of the G-allele [P = 0.0006; false discovery rate (FDR) = 0.026]. Strong correlations with secondary end points such as prolonged grade 4 neutropenia (P = 0.002, FDR = 0.046) were also observed. Additionally, two other SNPs in ABCC1/MRP1 (rs45511401 and rs246221) correlated with FN (P = 0.007 and P = 0.01, respectively; FDR = 0.16 and 0.19), as well as two SNPs in UGT2B7 and FGFR4 (P = 0.024 and P = 0.04; FDR = 0.28 and 0.38). CONCLUSION Genetic variability in ABCC1/MRP1 was associated with severe hematological toxicity of FEC.

The impact of adjuvant chemotherapy in older breast cancer patients on clinical and biological aging parameters

Purpose This prospective observational study aimed to evaluate the impact of adjuvant chemotherapy on biological and clinical markers of aging and frailty. Methods Women ≥ 70 years old with early breast cancer were enrolled after surgery and assigned to a chemotherapy (Docetaxel and Cyclophosphamide) group (CTG, n=57) or control group (CG, n=52) depending on their planned adjuvant treatment. Full geriatric assessment (GA) and Quality of Life (QoL) were evaluated at inclusion (T0), after 3 months (T1) and at 1 year (T2). Blood samples were collected to measure leukocyte telomere length (LTL), levels of interleukin-6 (IL-6) and other circulating markers potentially informative for aging and frailty: Interleukin-10 (IL-10), Tumor Necrosis Factor Alpha (TNF-α), Insulin-like Growth Factor 1 (IGF-1), Monocyte Chemotactic Protein 1 (MCP-1) and Regulated on Activation, Normal T cell Expressed and Secreted (RANTES). Results LTL decreased significantly but comparably in both groups, whereas IL-6 was unchanged at T2. However, IL-10, TNF-α, IGF-1 and MCP-1 suggested a minor biological aging effect of chemotherapy. Clinical frailty and QoL decreased at T1 in the CTG, but recovered at T2, while remaining stable in the CG. Conclusion Chemotherapy (TC) is unlikely to amplify clinical aging or induce frailty at 1 year. Accordingly, there is no impact on the most established aging biomarkers (LTL, IL-6).

Pertuzumab and trastuzumab with or without metronomic chemotherapy for older patients with HER2-positive metastatic breast cancer (EORTC 75111-10114): an open-label, randomised, phase 2 trial from the Elderly Task Force/Breast Cancer Group

BACKGROUND Despite the high incidence of metastatic breast cancer and its related mortality in the elderly population, our knowledge about optimal treatment for older patients with cancer is far from adequate. We aimed to evaluate the efficacy of dual anti-HER2 treatment with or without metronomic chemotherapy in older patients with HER2-positive metastatic breast cancer. METHODS We did a multicentre, open-label, randomised, phase 2 trial in 30 centres from eight countries in Europe, in patients with histologically proven, HER2-positive metastatic breast cancer, without previous chemotherapy for metastatic disease, who were 70 years or older, or 60 years or older with confirmed functional restrictions defined by protocol, and had a life expectancy of more than 12 weeks and a performance status according to WHO scale of 0-3. Eligible patients were randomly assigned (1:1) by an online randomisation system based on the minimisation method to receive metronomic oral cyclophosphamide 50 mg per day plus trastuzumab and pertuzumab, or trastuzumab and pertuzumab alone. Trastuzumab was given intravenously with a loading dose of 8 mg/kg, followed by 6 mg/kg every 3 weeks. Pertuzumab was given intravenously with a loading dose of 840 mg, followed by 420 mg every 3 weeks. Patients were stratified by hormone receptor positivity, previous HER2 treatment, and baseline geriatric screening. The primary endpoint was investigator-assessed progression-free survival at 6 months as per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. A difference of 10% or greater between the two groups was sought. Efficacy analyses were by intention to treat; safety was assessed in all patients who received at least one dose of study treatment. In case of progression, all patients were offered trastuzumab emtansine. This trial is registered with ClinicalTrials.gov, number NCT01597414, and is completed. FINDINGS Between July 2, 2013, and May 10, 2016, 80 patients, of whom 56 (70%) had a potential frailty profile according to the geriatric screening G8 score (≤14), were randomly assigned to receive trastuzumab and pertuzumab (n=39) or trastuzumab and pertuzumab plus metronomic oral cyclophosphamide (n=41). Estimated progression-free survival at 6 months was 46·2% (95% CI 30·2-60·7) with trastuzumab and pertuzumab versus 73·4% (56·6-84·6) with trastuzumab and pertuzumab plus metronomic oral cyclophosphamide (hazard ratio [HR] 0·65 [95% CI 0·37-1·12], p=0·12). At a median follow-up of 20·7 months (IQR 12·5-30·4), the median progression-free survival was 5·6 months (95% CI 3·6-16·8) with trastuzumab and pertuzumab versus 12·7 months (6·7-24·8) with the addition of metronomic oral cyclophosphamide. The most frequent grade 3-4 adverse events were hypertension (in six [15%] of 39 patients in the trastuzumab and pertuzumab group vs five [12%] of 41 in the trastuzumab and pertuzumab plus metronomic oral cyclophosphamide group), diarrhoea (four [10%] vs five [12%]), dyspnoea (two [5%] vs four [10%]), fatigue (three [8%] vs two [5%]), pain (two [5%] vs two [5%]), and a thromboembolic event (0 [0%] vs four [10%]). Severe cardiac toxicities were occasionally observed in both groups. In the trastuzumab and pertuzumab group four patients died without progression, due to cardiac arrest during treatment (n=1), peritoneal infection (n=1), respiratory failure (n=1), and sudden death without a specified cause (n=1). In the trastuzumab and pertuzumab plus metronomic oral cyclophosphamide group, one patient died from heart failure. INTERPRETATION Addition of metronomic oral cyclophosphamide to trastuzumab plus pertuzumab in older and frail patients with HER2-positive metastatic breast cancer increased median progression-free survival by 7 months compared with dual HER2 blockade alone, with an acceptable safety profile. Trastuzumab and pertuzumab plus metronomic oral cyclophosphamide, followed by trastuzumab emtansine after disease progression, might delay or supersede the need for taxane chemotherapy in this population. FUNDING F Hoffmann-La Roche.

Circulating CCL5 Levels in Patients with Breast Cancer: Is There a Correlation with Lymph Node Metastasis?

CC-chemokine ligand 5 (CCL5) was measured in plasma of 238 patients with breast cancer and in serum of 149 of these patients. Mean circulating CCL5 levels tended to be higher in patients with lymph-node-positive breast cancer, larger tumour sizes, the presence of lymphovascular invasion, and multifocal tumours. Additionally, circulating CCL5 levels were higher in the order of stages III, II, and I. The addition of circulating CCL5 concentration to known clinicopathological predictors for lymph node involvement did not allow more precise prediction of the lymph node status. These results suggest that CCL5 is a biomarker for tumour load rather than for lymph node involvement. As such, it might be helpful to identify patients with escape from immunosurveillance who will benefit from therapies to restore immune function.

P5-05-01: Vitamin D Status in Newly Diagnosed Breast Cancer Patients Inversely Correlates with Tumor Size and Moderately Correlates with Outcome.

Aims: To study the impact of Vitamin D (VitD) status and genetic variability in key VitD regulatory genes on patient and breast tumor characteristics, and on breast cancer related outcome. Methods: We examined serum 25-hydroxyvitamin D3 (25OHD) levels in a cohort of 1800 early breast cancer patients treated in Leuven between 2003 and 2010. Serum was collected at diagnosis for all patients; germline DNA from peripheral blood was also available for the majority of them. Serum 25OHD was measured by radioimmunoassay, and single nucleotide polymorphisms (SNP9s) were assessed by Sequenom. Statistical analysis was done by multivariable regression models including age, BMI and season and by a Cox proportional hazard model for analysis of disease-specific survival and disease-free interval. Results: Lower 25OHD serum levels were significantly correlated with larger tumor size (0,4 ng/ml decrease in 25OHD per 1 cm increment in tumor size, p=0.0063) but not with lymph node invasion, estrogen receptor and HER2 status, or tumor grade. Serum 25ODH level was significantly affected by genotypes of rs10741657 and rs1993116 (25-hydroxylase; CYP2R1) and of rs222040, rs7041 and rs4588 (D-binding protein; DBP), yet its observed association with tumor size did not differ between distinct genotypes. Although not statistically significant, patients with higher 25OHD levels tended to have slightly improved survival. Also, a significant increase in relapse risk became apparent after 3 years for patients with 25OHD Conclusion: Vitamin D Level in breast cancer patients inversely correlates with tumor size and moderately correlates with outcome. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-05-01.

Cell-free DNA profiling of metastatic prostate cancer reveals microsatellite instability, structural rearrangements and clonal hematopoiesis

Background There are multiple existing and emerging therapeutic avenues for metastatic prostate cancer, with a common denominator, which is the need for predictive biomarkers. Circulating tumor DNA (ctDNA) has the potential to cost-efficiently accelerate precision medicine trials to improve clinical efficacy and diminish costs and toxicity. However, comprehensive ctDNA profiling in metastatic prostate cancer to date has been limited. Methods A combination of targeted- and low-pass whole genome sequencing was performed on plasma cell-free DNA and matched white blood cell germline DNA in 364 blood samples from 217 metastatic prostate cancer patients. Results ctDNA was detected in 85.9% of baseline samples, correlated to line of therapy and was mirrored by circulating tumor cell enumeration of synchronous blood samples. Comprehensive profiling of the androgen receptor (AR) revealed a continuous increase in the fraction of patients with intra-AR structural variation, from 15.4% during first line mCRPC therapy to 45.2% in fourth line, indicating a continuous evolution of AR during the course of the disease. Patients displayed frequent alterations in DNA repair deficiency genes (18.0%). Additionally, the microsatellite instability phenotype was identified in 3.81% of eligible samples (≥0.1 ctDNA fraction). Sequencing of non-repetitive intronic- and exonic regions of PTEN, RB1 and TP53 detected biallelic inactivation in 47.5%, 20.3% and 44.1% of samples with ≥0.2 ctDNA fraction, respectively. Only one patient carried a clonal high-impact variant without a detectable second hit. Intronic high-impact structural variation was twice as common as exonic mutations in PTEN and RB1. Finally, 14.6% of patients presented false positive variants due to clonal hematopoiesis, commonly ignored in commercially available assays. Conclusions ctDNA profiles appear to mirror the genomic landscape of metastatic prostate cancer tissue and may cost-efficiently provide somatic information in clinical trials designed to identify predictive biomarkers. However, intronic sequencing of the interrogated tumor suppressors challenge the ubiquitous focus on coding regions and is vital, together with profiling of synchronous white blood cells, to minimize erroneous assignments which in turn may confound results and impede true associations in clinical trials.

Circulating tumor cells and survival in abiraterone- and enzalutamide-treated patients with castration-resistant prostate cancer

The outcome to treatment administered to patients with metastatic castration‐resistant prostate cancer (mCRPC) greatly differs between individuals, underlining the need for biomarkers guiding treatment decision making.

Low levels of intra-tumoural T cells in breast cancer identify clinically frail patients with shorter disease-specific survival

OBJECTIVES The global health status of older patients with cancer influences their clinical course, but little is known regarding the influence of the immune system on the global health of older patients with cancer. The goal of this study was to assess the relationships between patient fitness/frailty status and survival, and the local tumour immune environment of older patients with breast cancer. MATERIALS AND METHODS In a cohort of 58 older patients with breast cancer (over 70 years of age), fluorescence microscopy was used to investigate whether levels of intra-tumoural T cells (CD3+) and granulocytic cells (CD15+) could predict clinical outcome, and/or whether they correlated with patient physical and mental performance as evaluated by comprehensive geriatric assessment. RESULTS We observed that patients with higher levels of intra-tumoural T cells were fitter according to a number of clinical health measures including G8 (p = 0.006), Karnofsky Index (p = 0.0372), and Leuven Oncology Frailty Score (LOFS) (p = 0.0187). In contrast, high relative levels of granulocytic cells were found in patients with poorer clinical health (LOFS, p = 0.0474). Furthermore, high levels of T cells but not granulocytic cells were associated with longer breast cancer-specific survival (p = 0.0444). CONCLUSIONS This is the first study to show that low relative levels of intra-tumoural T cells are associated with inferior patient fitness. In contrast to T cells, we observed that intra-tumoural granulocytic cells displayed an inverse relationship with patient performance. Further research is needed to determine whether boosting the level of intra-tumoural T cells in older non-fit patients can result in improved outcome.