Everolimus plus endocrine therapy beyond CDK4/6 inhibitors progression for HR+ /HER2- advanced breast cancer: a real-world evidence cohort.

PURPOSE: Everolimus in combination with endocrine therapy (ET) was formerly approved as 2nd-line therapy in HR(+)/HER2(-) advanced breast cancer (aBC) patients (pts) progressing during or after a non-steroidal aromatase inhibitor (NSAI). Since this approval, the treatment landscape of aBC has changed dramatically, particularly with the arrival of CDK 4-6 inhibitors. Endocrine monotherapy after progression to CDK4/6 inhibitors has shown a limited progression-free survival (PFS), below 3 months. Evidence of the efficacy of everolimus plus ET after CDK4/6 inhibitors is scarce. METHODS: A retrospective observational study of patients with aBC treated with everolimus and ET beyond CDK4/6-i progression compiled from February 2015 to December 2022 in 4 Spanish hospitals was performed. Clinical and demographic data were collected from medical records. The main objective was to estimate the median progression-free survival (mPFS). Everolimus adverse events (AE) were registered. Quantitative variables were summarized with medians; qualitative variables with proportions and the Kaplan-Meier method were used for survival estimates. RESULTS: One hundred sixty-one patients received everolimus plus ET (exemestane: 96, fulvestrant: 54, tamoxifen: 10, unknown: 1) after progressing on a CDK4/6 inhibitor. The median follow-up time was 15 months (interquartile range: 1-56 months). The median age at diagnosis was 49 years (range: 35-90 years). The estimated mPFS was 6.0 months (95%CI 5.3-7.8 months). PFS was longer in patients with previous CDK4/6 inhibitor therapy lasting for > 18 months (8.7 months, 95%CI 6.6-11.3 months), in patients w/o visceral metastases (8.0 months, 95%CI 5.8-10.5 months), and chemotherapy-naïve in the metastatic setting (7.2 months, 95%CI 5.9-8.4 months). CONCLUSION: This retrospective analysis cohort of everolimus plus ET in mBC patients previously treated with a CDK4/6 inhibitor suggests a longer estimated mPFS when compared with the mPFS with ET monotherapy obtained from current randomized clinical data. Everolimus plus ET may be considered as a valid control arm in novel clinical trial designs.

Correlation between breast cancer subtypes determined by immunohistochemistry and n-COUNTER PAM50 assay: a real-world study.

PURPOSE: Molecular subtyping based on gene expression profiling (i.e., PAM50 assay) aids in determining the prognosis and treatment of breast cancer (BC), particularly in hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative tumors, where luminal A and B subtypes have different prognoses and treatments. Several surrogate classifications have been proposed for distinguishing between the luminal A and B subtypes. This study determines the accuracy of local immunohistochemistry (IHC) techniques for classifying HR-positive/HER2-negative (HR+/HER2-) tumors according to intrinsic subtypes using the nCOUNTER PAM50 assay as reference and the HR status definition according the ASCO/CAP recommendations. METHODS: Molecular subtypes resulting from nCOUNTER PAM50 performed in our laboratory between 2014 and 2020 were correlated with three different proxy surrogates proposed in the literature based on ER, PR, HER2, and Ki67 expression with different cut-off values. Concordance was measured using the level of agreement and kappa statistics. RESULTS: From 1049 samples with the nCOUNTER test, 679 and 350 were luminal A and B subtypes, respectively. Only a poor-to-fair correlation was observed between the three proxy surrogates and real genomic subtypes as determined by nCOUNTER PAM50. Moreover, 5-11% and 18-36% of the nCOUNTER PAM50 luminal B and A tumors were classified as luminal A and B, respectively, by these surrogates. CONCLUSION: The concordance between luminal subtypes determined by three different IHC-based classifiers and the nCOUNTER PAM50 assay was suboptimal. Thus, a significant proportion of luminal A and B tumors as determined by the surrogate classifiers could be undertreated or over-treated.

Study design for DESTINY-Breast Respond HER2-low Europe: T-DXd in patients with HER2-low advanced breast cancer.

Trastuzumab deruxtecan (T-DXd) is approved for the treatment of human epidermal growth factor receptor 2 (HER2)-low metastatic breast cancer (mBC). Results on T-DXd treatment in HER2-low mBC have so far been limited to clinical trials. DESTINY-Breast Respond HER2-low Europe (NCT05945732) is a multi-center, multi-country, observational, prospective, non-interventional study planning to enroll 1350 patients from 216 sites receiving T-DXd or conventional chemotherapy as their routine clinical care for advanced stage breast cancer in 12 European countries. This non-interventional study will provide real-world insight into T-DXd treatment for HER2-low mBC with data on effectiveness, safety and tolerability, patient-reported outcomes, treatment patterns, geriatric health status and HER2 testing. This will be beneficial for improving guidance to maximize patient treatment benefit.

Trastuzumab deruxtecan (T-DXd; Enhertu^®) is a medicine approved to treat cancers that produce a protein called HER2 on the surface of cancer cells. T-DXd works by targeting the HER2 protein to deliver chemotherapy directly to cancer cells. Until recently, breast cancers were classified as HER2-positive (high level of HER2 protein on cancer cells) or HER2-negative (very low level/no HER2 protein on cancer cells). T-DXd was approved for treating patients with HER2-positive advanced breast cancer in Europe in 2022. In 2023 the DESTINY-Breast04 clinical trial showed that T-DXd was more effective than current standard chemotherapies, when treating advanced breast cancer patients with low levels of the HER2 protein (historically classified as HER2-negative cancer). This trial led to the approval of T-DXd for treating advanced HER2-low breast cancer, providing a new treatment option for 50­60% of breast cancer patients. More information is needed about T-DXd treatment in the real world (for patients treated in the hospital, rather than in a clinical trial). This article describes the purpose and design of the DESTINY-Breast Respond HER2-low Europe study, which will collect and report more information about how effective T-DXd treatment is in the real world. This is a large study aiming to include 1350 eligible patients from 12 countries across Europe. Patients will report their experience of side effects (such as nausea and vomiting) to improve management of T-DXd treatment and maximize patient benefit. The study will also examine how elderly patients respond to T-DXd treatment, and how HER2 levels are being tested.Clinical Trial Registration: ICH CGP: NCT05945732, registered on 6 July 2023 (ClinicalTrials.gov).

A likelihood ratio approach for utilizing case-control data in the clinical classification of rare sequence variants: application to BRCA1 and BRCA2.

A large number of variants identified through clinical genetic testing in disease susceptibility genes, are of uncertain significance (VUS). Following the recommendations of the American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology (AMP), the frequency in case-control datasets (PS4 criterion), can inform their interpretation. We present a novel case-control likelihood ratio-based method that incorporates gene-specific age-related penetrance. We demonstrate the utility of this method in the analysis of simulated and real datasets. In the analyses of simulated data, the likelihood ratio method was more powerful compared to other methods. Likelihood ratios were calculated for a case-control dataset of BRCA1 and BRCA2 variants from the Breast Cancer Association Consortium (BCAC), and compared with logistic regression results. A larger number of variants reached evidence in favor of pathogenicity, and a substantial number of variants had evidence against pathogenicity - findings that would not have been reached using other case-control analysis methods. Our novel method provides greater power to classify rare variants compared to classical case-control methods. As an initiative from the ENIGMA Analytical Working Group, we provide user-friendly scripts and pre-formatted excel calculators for implementation of the method for rare variants in BRCA1, BRCA2 and other high-risk genes with known penetrance.

XENERA-1: a randomised double-blind Phase II trial of xentuzumab in combination with everolimus and exemestane versus everolimus and exemestane in patients with hormone receptor-positive/HER2-negative metastatic breast cancer and non-visceral disease.

BACKGROUND: Xentuzumab is a humanised monoclonal antibody that binds to IGF-1 and IGF-2, neutralising their proliferative activity and restoring inhibition of AKT by everolimus. This study evaluated the addition of xentuzumab to everolimus and exemestane in patients with advanced breast cancer with non-visceral disease. METHODS: This double-blind, randomised, Phase II study was undertaken in female patients with hormone-receptor (HR)-positive/human epidermal growth factor 2 (HER2)-negative advanced breast cancer with non-visceral disease who had received prior endocrine therapy with or without CDK4/6 inhibitors. Patients received a weekly intravenous infusion of xentuzumab (1000 mg) or placebo in combination with everolimus (10 mg/day orally) and exemestane (25 mg/day orally). The primary endpoint was progression-free survival (PFS) per independent review. RESULTS: A total of 103 patients were randomised and 101 were treated (n = 50 in the xentuzumab arm and n = 51 in the placebo arm). The trial was unblinded early due to high rates of discordance between independent and investigator assessment of PFS. Per independent assessment, median PFS was 12.7 (95% CI 6.8-29.3) months with xentuzumab and 11.0 (7.7-19.5) months with placebo (hazard ratio 1.19; 95% CI 0.55-2.59; p = 0.6534). Per investigator assessment, median PFS was 7.4 (6.8-9.7) months with xentuzumab and 9.2 (5.6-14.4) months with placebo (hazard ratio 1.23; 95% CI 0.69-2.20; p = 0.4800). Tolerability was similar between the arms, with diarrhoea (33.3-56.0%), fatigue (33.3-44.0%) and headache (21.6-40.0%) being the most common treatment-emergent adverse events. The incidence of grade ≥ 3 hyperglycaemia was similar between the xentuzumab (2.0%) and placebo (5.9%) arms. CONCLUSIONS: While this study demonstrated that xentuzumab could be safely combined with everolimus and exemestane in patients with HR-positive/HER2-negative advanced breast cancer with non-visceral disease, there was no PFS benefit with the addition of xentuzumab. Trial registration ClinicalTrials.gov, NCT03659136. Prospectively registered, September 6, 2018.

Real-World Use of Highly Sensitive Liquid Biopsy Monitoring in Metastatic Breast Cancer Patients Treated with Endocrine Agents after Exposure to Aromatase Inhibitors.

Endocrine-resistant, hormone receptor-positive, and HER2-negative (HR+/HER2-) metastatic breast cancer (mBC) is largely governed by acquired mutations in the estrogen receptor, which promote ligand-independent activation, and by truncal alterations in the PI3K signaling pathway, with a broader range of gene alterations occurring with less prevalence. Circulating tumor DNA (ctDNA)-based technologies are progressively permeating the clinical setting. However, their utility for serial monitoring has been hindered by their significant costs, inter-technique variability, and real-world patient heterogeneity. We interrogated a longitudinal collection of 180 plasma samples from 75 HR+/HER2- mBC patients who progressed or relapsed after exposure to aromatase inhibitors and were subsequently treated with endocrine therapy (ET) by means of highly sensitive and affordable digital PCR and SafeSEQ sequencing. Baseline PIK3CA and TP53 mutations were prognostic of a shorter progression-free survival in our population. Mutant PIK3CA was prognostic in the subset of patients receiving fulvestrant monotherapy after progression to a CDK4/6 inhibitor (CDK4/6i)-containing regimen, and its suppression was predictive in a case of long-term benefit with alpelisib. Mutant ESR1 was prognostic in patients who did not receive concurrent CDK4/6i, an impact influenced by the variant allele frequency, and its early suppression was strongly predictive of efficacy and associated with long-term benefit in the whole cohort. Mutations in ESR1, TP53, and KRAS emerged as putative drivers of acquired resistance. These findings collectively contribute to the characterization of longitudinal ctDNA in real-world cases of HR+/HER2- mBC previously exposed to aromatase inhibitors and support ongoing studies either targeting actionable alterations or leveraging the ultra-sensitive tracking of ctDNA.

Modeling the Prognostic Impact of Circulating Tumor Cells Enumeration in Metastatic Breast Cancer for Clinical Trial Design Simulation.

Despite the strong prognostic stratification of circulating tumor cells (CTCs) enumeration in metastatic breast cancer (MBC), current clinical trials usually do not include a baseline CTCs in their design. This study aimed to generate a classifier for CTCs prognostic simulation in existing datasets for hypothesis generation in patients with MBC. A K-nearest neighbor machine learning algorithm was trained on a pooled dataset comprising 2436 individual MBC patients from the European Pooled Analysis Consortium and the MD Anderson Cancer Center to identify patients likely to have CTCs ≥ 5/7 mL blood (StageIVaggressive vs StageIVindolent). The model had a 65.1% accuracy and its prognostic impact resulted in a hazard ratio (HR) of 1.89 (Simulatedaggressive vs SimulatedindolentP < .001), similar to patients with actual CTCs enumeration (HR 2.76; P < .001). The classifier's performance was then tested on an independent retrospective database comprising 446 consecutive hormone receptor (HR)-positive HER2-negative MBC patients. The model further stratified clinical subgroups usually considered prognostically homogeneous such as patients with bone-only or liver metastases. Bone-only disease classified as Simulatedaggressive had a significantly worse overall survival (OS; P < .0001), while patients with liver metastases classified as Simulatedindolent had a significantly better prognosis (P < .0001). Consistent results were observed for patients who had undergone CTCs enumeration in the pooled population. The differential prognostic impact of endocrine- (ET) and chemotherapy (CT) was explored across the simulated subgroups. No significant differences were observed between ET and CT in the overall population, both in terms of progression-free survival (PFS) and OS. In contrast, a statistically significant difference, favoring CT over ET was observed among Simulatedaggressive patients (HR: 0.62; P = .030 and HR: 0.60; P = .037, respectively, for PFS and OS).

Association of germline genetic variants with breast cancer-specific survival in patient subgroups defined by clinic-pathological variables related to tumor biology and type of systemic treatment.

BACKGROUND: Given the high heterogeneity among breast tumors, associations between common germline genetic variants and survival that may exist within specific subgroups could go undetected in an unstratified set of breast cancer patients. METHODS: We performed genome-wide association analyses within 15 subgroups of breast cancer patients based on prognostic factors, including hormone receptors, tumor grade, age, and type of systemic treatment. Analyses were based on 91,686 female patients of European ancestry from the Breast Cancer Association Consortium, including 7531 breast cancer-specific deaths over a median follow-up of 8.1 years. Cox regression was used to assess associations of common germline variants with 15-year and 5-year breast cancer-specific survival. We assessed the probability of these associations being true positives via the Bayesian false discovery probability (BFDP < 0.15). RESULTS: Evidence of associations with breast cancer-specific survival was observed in three patient subgroups, with variant rs5934618 in patients with grade 3 tumors (15-year-hazard ratio (HR) [95% confidence interval (CI)] 1.32 [1.20, 1.45], P = 1.4E-08, BFDP = 0.01, per G allele); variant rs4679741 in patients with ER-positive tumors treated with endocrine therapy (15-year-HR [95% CI] 1.18 [1.11, 1.26], P = 1.6E-07, BFDP = 0.09, per G allele); variants rs1106333 (15-year-HR [95% CI] 1.68 [1.39,2.03], P = 5.6E-08, BFDP = 0.12, per A allele) and rs78754389 (5-year-HR [95% CI] 1.79 [1.46,2.20], P = 1.7E-08, BFDP = 0.07, per A allele), in patients with ER-negative tumors treated with chemotherapy. CONCLUSIONS: We found evidence of four loci associated with breast cancer-specific survival within three patient subgroups. There was limited evidence for the existence of associations in other patient subgroups. However, the power for many subgroups is limited due to the low number of events. Even so, our results suggest that the impact of common germline genetic variants on breast cancer-specific survival might be limited.

Trajectories of alcohol consumption during life and the risk of developing breast cancer.

BACKGROUND: Whether there are lifetime points of greater sensitivity to the deleterious effects of alcohol intake on the breasts remains inconclusive. OBJECTIVE: To compare the influence of distinctive trajectories of alcohol consumption throughout a woman's life on development of breast cancer (BC). METHODS: 1278 confirmed invasive BC cases and matched (by age and residence) controls from the Epi-GEICAM study (Spain) were used. The novel group-based trajectory modelling was used to identify different alcohol consumption trajectories throughout women's lifetime. RESULTS: Four alcohol trajectories were identified. The first comprised women (45%) with low alcohol consumption (<5 g/day) throughout their life. The second included those (33%) who gradually moved from a low alcohol consumption in adolescence to a moderate in adulthood (5 to <15 g/day), never having a high consumption; and oppositely, women in the third trajectory (16%) moved from moderate consumption in adolescence, to a lower consumption in adulthood. Women in the fourth (6%) moved from a moderate alcohol consumption in adolescence to the highest consumption in adulthood (≥15 g/day), never having a low alcohol consumption. Comparing with the first trajectory, the fourth doubled BC risk (OR 2.19; 95% CI 1.27, 3.77), followed by the third (OR 1.44; 0.96, 2.16) and ultimately by the second trajectory (OR 1.17; 0.86, 1.58). The magnitude of BC risk was greater in postmenopausal women, especially in those with underweight or normal weight. When alcohol consumption was independently examined at each life stage, ≥15 g/day of alcohol consumption in adolescence was strongly associated with BC risk followed by consumption in adulthood. CONCLUSIONS: The greater the alcohol consumption accumulated throughout life, the greater the risk of BC, especially in postmenopausal women. Alcohol consumption during adolescence may particularly influence BC risk.

Management of Abemaciclib-Associated Adverse Events in Patients with Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer: Safety Analysis of MONARCH 2 and MONARCH 3.

BACKGROUND: Abemaciclib demonstrated efficacy in hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer. Here we provide a comprehensive summary of the most common adverse events (AEs), their management, and whether AEs or dose reductions influenced progression-free survival (PFS), in the MONARCH 2 and 3 trials. MATERIALS AND METHODS: Incidence of the most clinically relevant AEs, management, and outcomes were summarized. Time-dependent covariate analyses examined the impact of dose reductions on PFS. PFS was estimated for patients with and without early onset of diarrhea or neutropenia. RESULTS: The most frequently reported AE was diarrhea, with clinically significant diarrhea (grade ≥2) reported for 42.8% of patients taking abemaciclib. Median time to onset was 1 week, and duration ranged from 6 to 12 days, depending on grade and study. Diarrhea was adequately managed by antidiarrheal medication (72.8%), dose omissions (17.3%), and reductions (16.7%). The highest rates of grade ≥2 diarrhea were observed in the first cycles and decreased in subsequent cycles. Neutropenia (grade ≥3) occurred in 25.4% of abemaciclib-treated patients. Neutropenia resolved with dose omissions (16.8%) and/or dose reductions (11.2%). Incidence of febrile neutropenia (0.7%) or other relevant grade ≥3 hematological events (<9%) was low. Venous thromboembolic events (5.3%) were primarily treated with anticoagulants. Interstitial lung disease/pneumonitis (3.4%) was treated with corticosteroids and/or antibiotics. PFS benefit of abemaciclib was not impacted by dose reductions or early onset of toxicities. CONCLUSION: Abemaciclib was generally well tolerated. The most common AEs were effectively managed by supportive medications, and/or dose adjustments, with no detriment to PFS. IMPLICATIONS FOR PRACTICE: Treatment with abemaciclib plus fulvestrant or nonsteroidal aromatase inhibitors is generally well tolerated in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer. In MONARCH 2 and MONARCH 3, any-grade diarrhea and grade ≥3 neutropenia were effectively managed with supportive medication and/or dose adjustment. Venous thromboembolic events were treated with anticoagulants and did not often require treatment discontinuation. Interstitial lung disease/pneumonitis was infrequent and treated with corticosteroids and/or antibiotics. Clinicians should be aware of and implement management strategies, including dose adjustments according to local labels, for commonly occurring and serious adverse events to ensure continued treatment and optimize clinical benefit/risk ratio.

GEICAM Guidelines for the Management of Patients with Breast Cancer During the COVID-19 Pandemic in Spain.

Breast cancer (BC) is the most common cancer in women in Spain. During the COVID-19 pandemic caused by the SARS-CoV-2 virus, patients with BC still require timely treatment and follow-up; however, hospitals are overwhelmed with infected patients and, if exposed, patients with BC are at higher risk for infection and serious complications if infected. Thus, health care providers need to evaluate each BC treatment and in-hospital visit to minimize pandemic-associated risks while maintaining adequate treatment efficacy. Here we present a set of guidelines regarding available options for BC patient management and treatment by BC subtype in the context of the COVID-19 pandemic. Owing to the lack of evidence about COVID-19 infection, these recommendations are mainly based on expert opinion, medical organizations' and societies' recommendations, and some published evidence. We consider this a useful tool to facilitate medical decision making in this health crisis situation we are facing. IMPLICATIONS FOR PRACTICE: This work presents a set of guidelines regarding available options for breast cancer (BC) patient management and treatment by BC subtype in the context of the COVID-19 pandemic. Owing to the suddenness of this health crisis, specialists have to make decisions with little evidence at hand. Thus, these expert guidelines may be a useful tool to facilitate medical decision making in the context of a worldwide pandemic with no resources to spare.

Abemaciclib, a CDK4 and CDK6 inhibitor for the treatment of metastatic breast cancer.

The addition of CDK4 and 6 inhibitors (abemaciclib, palbociclib or ribociclib) to endocrine therapy, as first-line treatment or following progression after initial endocrine therapy, significantly increased progression-free survival, objective response rates and in some trials overall survival, compared with endocrine therapy alone in HR+ and HER2- breast metastatic breast cancer. These CDK4 and 6 inhibitors are now approved in this context and have become a new standard of care. A hypothesis-generating exploratory analysis suggested that the addition of abemaciclib to endocrine therapy showed the largest effects in subgroups of women with indicators of poor prognosis, although these data require confirmation. This review provides updated clinical trial data for all three drugs in metastatic breast cancer, focusing on abemaciclib, the most recently approved agent.

A phase Ib study of sonidegib (LDE225), an oral small molecule inhibitor of smoothened or Hedgehog pathway, in combination with docetaxel in triple negative advanced breast cancer patients: GEICAM/2012-12 (EDALINE) study.

Up-regulation of the Hedgehog (Hh) pathway is implicated in the genesis of a wide range of tumors including triple negative breast cancer (TNBC). Sonidegib is a potent and selective oral inhibitor of Smo, a key component of the Hh signaling pathway. We designed a phase I clinical study to explore the combination of sonidegib plus docetaxel (fixed dose at 75 mg/m2) in advanced TNBC patients. The primary objective was to ascertain the combination's maximum tolerated dose and the recommended phase II dose (RP2D), based on dose limiting toxicities (DLTs) in the first 2 cycles. A standard "3 + 3" design was followed including three dose levels (DL) of sonidegib: 400 mg (DL1), 600 mg (DL2), and 800 mg (DL3). Twelve patients were included. Sonidegib 800 mg orally q.d. plus docetaxel 75 mg/m2 given intravenously on day 1 of 21-day cycles was established as the RP2D. No DLTs were observed at any DL. The median number of administered cycles at DL3 was 8 (range: 6 to 9). Grade 3 adverse events (AEs) at DL3 were neutropenia (66.7%), CPK increase (33.3%), leukopenia (33.3%), and paresthesia (33.3%), grade 4 AEs were not reported at this DL. At the RP2D, the combination showed antitumor activity in three out of 10 patients with measurable disease. Median time to progression for the overall study was 42.5 days (95% Confidence Interval: 29-155), and 188 days at DL3. No drug-to-drug interactions between sonidegib and docetaxel were found in the PK assessment. Trial Registration: EudraCT study number: 2013-001750-96. Study GEICAM/2012-12. TRIAL REGISTRATION: EudraCT study number: 2013-001750-96. Study GEICAM/2012-12. ClinicalTrials.gov: NCT02027376.

Safety of eribulin as third-line chemotherapy in HER2-negative, advanced breast cancer pre-treated with taxanes and anthracycline: OnSITE study.

Eribulin is active and safe in heavily pre-treated metastatic breast cancer patients. Few safety data have been published in third line. We aimed to report the specific safety profile on third line beyond taxanes and anthracyclines in advanced breast cancer (ABC). A multicenter phase II, prospective study was conducted in anthracyclines and taxanes pre-treated HER2-negative ABC, programmed to receive eribulin as third-line chemotherapy. Adverse events (AEs) were assessed and classified according to CTCAE. In addition, efficacy, in terms of overall survival (OS) and progression-free survival (PFS), and the dynamics of circulating tumor cells (CTCs) during treatment were assessed. 59 patients fulfilled the criteria. All but one showed AEs with a cumulative number of 598 AEs. The most frequent grade 3/4 drug-related AEs were neutropenia (1.7%), febrile neutropenia (0.5%), leukopenia (0.5%), alopecia (0.5%), asthenia (0.3%), elevated gamma glutamyl transferase levels (0.2%), and respiratory tract infection (0.2%). Median PFS was 4 months (95% CI 3.1-5.9) and median OS was 13.6 months (11.8-not reached). The mean number of CTCs in peripheral blood was significantly reduced from baseline to cycle 2 (16.8 vs 5.4 CTCs; P < 0.001). Median OS was significantly longer in <5 baseline CTC patients compared to ≥5 baseline CTC patients (13.1 months [95% CI: 11.8-not reached] vs 12.5 months [95% CI: 7.6-not reached]; P = 0.045). A significant correlation (P = 0.0129) was observed between CTC levels at cycle 2 and death when CTCs were analyzed using cox regression. Eribulin chemotherapy is effective and safe as third line in advanced HER2-negative breast cancer. CTC levels correlate with overall survival.

Pharmacogenetic variants and response to neoadjuvant single-agent doxorubicin or docetaxel: a study in locally advanced breast cancer patients participating in the NCT00123929 phase 2 randomized trial.

OBJECTIVES: Taxanes and anthracyclines are widely used in the treatment of breast cancer, although the benefit is limited to a proportion of patients and predictive biomarkers for clinical outcome remain elusive. PATIENTS AND METHODS: We carried out a pharmacogenetic study in 181 patients with locally advanced breast cancer enrolled in a phase 2 randomized clinical trial (NCT00123929), where patients were randomly assigned to receive neoadjuvant single-agent docetaxel 100 mg/m(2) (n=84) or doxorubicin 75 mg/m(2) (n=97). We studied the association of 226 single nucleotide polymorphisms (SNPs) in 15 key drug biotransformation genes with neoadjuvant pathological tumor response residual cancer burden index to docetaxel and to doxorubicin. RESULTS: We identified a significant association for rs162561, an intronic SNP located in the cytochrome P450 family 1 subfamily B member 1 (CYP1B1) gene, with tumor response in patients treated with single-agent docetaxel (dominant model: ß=1.02, 95% confidence interval=0.49-1.55; P=1.77×10(-4)), and for rs717620, an SNP located in the promoter of the ATP-binding cassette subfamily C member 2 (ABCC2) gene, in patients treated with neoadjuvant doxorubicin (recessive model: ß=1.67; 95% confidence interval=0.26-3.11; P=0.02). CONCLUSION: We identified two polymorphisms in CYP1B1 and ABCC2 associated with tumor pathological response following docetaxel or doxorubicin neoadjuvant monotherapy, respectively. Although further validation is required, these variants could be potential predictive genetic markers for treatment outcome in breast cancer patients.

Exome array analysis identifies ETFB as a novel susceptibility gene for anthracycline-induced cardiotoxicity in cancer patients.

PURPOSE: Anthracyclines are widely used chemotherapeutic drugs that can cause progressive and irreversible cardiac damage and fatal heart failure. Several genetic variants associated with anthracycline-induced cardiotoxicity (AIC) have been identified, but they explain only a small proportion of the interindividual differences in AIC susceptibility. METHODS: In this study, we evaluated the association of low-frequency variants with risk of chronic AIC using the Illumina HumanExome BeadChip array in a discovery cohort of 61 anthracycline-treated breast cancer patients with replication in a second independent cohort of 83 anthracycline-treated pediatric cancer patients, using gene-based tests (SKAT-O). RESULTS: The most significant associated gene in the discovery cohort was ETFB (electron transfer flavoprotein beta subunit) involved in mitochondrial ß-oxidation and ATP production (P = 4.16 × 10-4) and this association was replicated in an independent set of anthracycline-treated cancer patients (P = 2.81 × 10-3). Within ETFB, we found that the missense variant rs79338777 (p.Pro52Leu; c.155C > T) made the greatest contribution to the observed gene association and it was associated with increased risk of chronic AIC in the two cohorts separately and when combined (OR 9.00, P = 1.95 × 10-4, 95% CI 2.83-28.6). CONCLUSIONS: We identified and replicated a novel gene, ETFB, strongly associated with chronic AIC independently of age at tumor onset and related to anthracycline-mediated mitochondrial dysfunction. Although experimental verification and further studies in larger patient cohorts are required to confirm our finding, we demonstrated that exome array data analysis represents a valuable strategy to identify novel genes contributing to the susceptibility to chronic AIC.

Experience with eribulin in patients with breast cancer and cutaneous metastases: case studies.

Skin localization occurs in about 25% of women with metastatic breast cancer and represents a major therapeutic challenge. Although clinical literature on response of cutaneous metastases to chemotherapy is scarce, good response to eribulin has been reported. Herein, the clinical courses of three women with skin lesions secondary to metastatic breast cancer are described. The first patient achieved a complete clinical response in skin metastases with good tolerability to fourth-line eribulin (progression-free survival [PFS]: 8.5 months). In the second case, eribulin administered as fifth-line chemotherapy produced an objective response and PFS of 6 months with good tolerability. The third patient also received eribulin in the fifth line and had a visible skin response from the first administration (PFS: 5 months).

Multicenter analysis of neoadjuvant docetaxel, carboplatin, and trastuzumab in HER2-positive breast cancer.

PURPOSE: In an era where neoadjuvant dual blockade is emerging as the standard of care for early and locally advanced HER2-positive breast cancer, we aimed to identify predictors of response to single-blockade chemotherapy. METHODS: This retrospective analysis reviewed all the incident stage I-III HER2-positive breast cancer patients who received neoadjuvant docetaxel, carboplatin, and trastuzumab (TCH) in three institutions. pCR was defined as the absence of invasive tumor in breast and axillary nodes (ypT0/isypN0). RESULTS: From 2008 to 2015, 84 patients receiving neoadjuvant TCH were identified within our institutions. The mean age at diagnosis was 51.8 years. 59.5% of the patients were hormone receptor (HR) positive, lymph node involvement occurred in 67.9%, and clinical distribution was 2.4, 65.5, and 32.1% for stage I, II, and III, respectively. pCR rate was 47.6%; there was a significantly lower response in HR-positive patients compared to HR-negative ones (34 vs 67.6%, p = 0.005). pCR rate was associated with tumor size, whereas differences did not reach significance either for stage or for nodal status. Multivariate analysis found that only HR status was associated with response (p = 0.003). At a median follow-up of 31.7 months, disease-free survival, distant disease-free survival, and overall survival were 78.6, 85.7, and 94%, respectively. Breast-conserving surgery was performed in 44% of the patients. Overall, TCH was well tolerated, with low rates of grade 3-4 adverse events, and neither late toxicities nor cardiac dysfunctions were reported. CONCLUSIONS: Neoadjuvant TCH, an anthracycline-free single-blockade regimen, achieved a pCR of 47.6%. Further molecular analyses are required in order to identify stronger predictive markers of pCR and thus for an accurate selection of patients who do not benefit from dual blockade.

Tumor burden monitoring using cell-free tumor DNA could be limited by tumor heterogeneity in advanced breast cancer and should be evaluated together with radiographic imaging.

BACKGROUND: Accurate measurement of tumor burden in breast cancer disease is essential to improve the clinical management of patients. In this study, we evaluate whether the fluctuations in the fraction of PIK3CA mutant allele correlates with tumor response according to RECIST criteria and tumor markers quantification. METHODS: Eighty six plasma samples were analyzed by digital PCR using Rare Mutation Assays for E542K, E545K and H1047R. Mutant cfDNA and tumor markers CA15-3 and CEA were compared with radiographic imaging. RESULTS: The agreement between PIK3CA mutation status in FFPE samples and circulating tumor DNA (ctDNA) was moderate (K = 0.591; 95% IC = 0.371-0.811). Restricting the analysis to the metastatic patients, we found a good agreement between PIK3CA mutation status assessed in liquid and solid biopsy (K = 0.798 95%; IC = 0.586-1). ctDNA showed serial changes with fluctuations correlating with tumor markers 15.3 and CEA in 7 out of 8 cases with Pearson correlation coefficients ranging from 0.99 to 0.46 and from 0.99 to 0.38 respectively. Similarly, fluctuations in the fraction of PIK3CA mutant allele always correlated with changes in lesion size seen on images, although in two cases it did not correlate with treatment responses as defined by RECIST criteria. CONCLUSION: oncogenic mutation quantification in plasma samples can be useful to monitor treatment outcome. However, it might be limited by tumor heterogeneity in advanced disease and it should be evaluated together with radiographic imaging.

Physical activity and breast cancer risk by pathological subtype.

OBJECTIVE: To examine the influence of physical activity on breast cancer risk and evaluate whether adherence to international recommendations is associated with a decreased risk. METHODS: This is a multicenter matched case-control study where 698 pairs completed a physical activity questionnaire. Recreational physical activity during the last year was quantified in metabolic equivalent hours per week (MET-h/week) and categorized in activities of moderate (3.0-5.9 MET) and vigorous (>6 MET) intensity. The adherence to World Cancer Research Fund and the American Institute for Cancer Research recommendation was also assessed. The association with breast cancer risk, overall and by pathologic subtype, was evaluated using conditional and multinomial logistic regression models. RESULTS: Mean MET-h/week was 16.6 among cases and 20.4 among controls. Premenopausal breast cancer risk decreased by 5% (P=0.007) for every 6 MET-h/week increase in energy expenditure. By contrast, postmenopausal women needed to do more intense exercise to observe benefits. The protection was more pronounced for nulliparous women, as well as for hormone receptor positive and HER2+ tumors. Physically inactive women displayed a 71% increased risk when compared with those who met the international recommendation (P=0.001). Finally, women who were inactive during the previous year, regardless of the overall physical activity reported in previous periods, showed an increased risk when compared to always active women. CONCLUSIONS: Women who report adherence to international physical activity recommendations entail a significant decrease in risk for all pathologic breast cancer subtypes. This is of particular interest in Spain, where a significant increase in overweight and obesity in recent decades is observed.