MIMESIS: minimal DNA-methylation signatures to quantify and classify tumor signals in tissue and cell-free DNA samples.

DNA-methylation alterations are common in cancer and display unique characteristics that make them ideal markers for tumor quantification and classification. Here we present MIMESIS, a computational framework exploiting minimal DNA-methylation signatures composed by a few dozen informative DNA-methylation sites to quantify and classify tumor signals in tissue and cell-free DNA samples. Extensive analyses of multiple independent and heterogenous datasets including >7200 samples demonstrate the capability of MIMESIS to provide precise estimations of tumor content and to enable accurate classification of tumor type and molecular subtype. To assess our framework for clinical applications, we designed a MIMESIS-informed assay incorporating the minimal signatures for breast cancer. Using both artificial samples and clinical serial cell-free DNA samples from patients with metastatic breast cancer, we show that our approach provides accurate estimations of tumor content, sensitive detection of tumor signal and the ability to capture clinically relevant molecular subtype in patients' circulation. This study provides evidence that our extremely parsimonious approach can be used to develop cost-effective and highly scalable DNA-methylation assays that could support and facilitate the implementation of precision oncology in clinical practice.

Clinical trials in older patients with cancer - typical challenges, possible solutions, and a paradigm of study design in breast cancer.

BACKGROUND AND PURPOSE: While the prevalence of older breast cancer patients is rapidly increasing, these patients are greatly underrepresented in clinical trials. We discuss barriers to recruitment of older patients to clinical trials and propose solutions on how to mitigate these challenges and design optimal clinical trials through the paradigm of IMPORTANT trial. PATIENTS AND METHODS: This is a narrative review of the current literature evaluating barriers to including older breast cancer patients in clinical trials and how mitigating strategies can be implemented in a pragmatic clinical trial. RESULTS: The recognized barriers can be roughly divided into trial design-related (e.g. the adoption of strict inclusion criteria, the lack of pre-specified age-specific analysis), patient-related (e.g. lack of knowledge, valuation of the quality-of-life instead of survival, transportation issues), or physician-related (e.g. concern for toxicity). Several strategies to mitigate barriers have been identified and should be considered when designing a clinical trial dedicated to older patients with cancer. The pragmatic, de-centralized IMPORTANT trial focusing on dose optimization of CDK4/6 -inhibitors in older breast cancer patients is a paradigm of a study design where different mitigating strategies have been adopted. INTERPRETATION: Because of the existing barriers, older adults in clinical trials are considerably healthier than the average older patients treated in clinical practice. Thus, the study results cannot be generalized to the older population seen in daily clinical practice. Broader inclusion/exclusion criteria, offering telehealth visits, and inclusion of patient-reported, instead of physician-reported outcomes may increase older patient participation in clinical trials.

Updated recommendations regarding the management of older patients with breast cancer: a joint paper from the European Society of Breast Cancer Specialists (EUSOMA) and the International Society of Geriatric Oncology (SIOG).

Breast cancer is increasingly prevalent in older adults and is a substantial part of routine oncology practice. However, management of breast cancer in this population is challenging because the disease is highly heterogeneous and there is insufficient evidence specific to older adults. Decision making should not be driven by age alone but should involve geriatric assessments plus careful consideration of life expectancy, competing risks of mortality, and patient preferences. A multidisciplinary taskforce, including members of the European Society of Breast Cancer Specialists and International Society of Geriatric Oncology, gathered to expand and update the previous 2012 evidence-based recommendations for the management of breast cancer in older individuals with the endorsement of the European Cancer Organisation. These guidelines were expanded to include chemotherapy toxicity prediction calculators, cultural and social considerations, surveillance imaging, genetic screening, gene expression profiles, neoadjuvant systemic treatment options, bone-modifying drugs, targeted therapies, and supportive care. Recommendations on geriatric assessment, ductal carcinoma in situ, screening, primary endocrine therapy, surgery, radiotherapy, adjuvant systemic therapy, and secondary breast cancer were updated.

Circulating tumor cells and palbociclib treatment in patients with ER-positive, HER2-negative advanced breast cancer: results from a translational sub-study of the TREnd trial.

BACKGROUND: Circulating tumor cells (CTCs) are prognostic in patients with advanced breast cancer (ABC). However, no data exist about their use in patients treated with palbociclib. We analyzed the prognostic role of CTC counts in patients enrolled in the cTREnd study, a pre-planned translational sub-study of TREnd (NCT02549430), that randomized patients with ABC to palbociclib alone or palbociclib plus the endocrine therapy received in the prior line of treatment. Moreover, we evaluated RB1 gene expression on CTCs and explored its prognostic role within the cTREnd subpopulation. METHODS: Forty-six patients with ER-positive, HER2-negative ABC were analyzed. Blood samples were collected before starting palbociclib treatment (timepoint T0), after the first cycle of treatment (timepoint T1), and at disease progression (timepoint T2). CTCs were isolated and counted by CellSearch® System using the CellSearch™Epithelial Cell kit. Progression-free survival (PFS), clinical benefit (CB) during study treatment, and time to treatment failure (TTF) after study treatment were correlated with CTC counts. Samples with ≥ 5 CTCs were sorted by DEPArray system® (DA). RB1 and GAPDH gene expression levels were measured by ddPCR. RESULTS: All 46 patients were suitable for CTCs analysis. CTC count at T0 did not show significant prognostic value in terms of PFS and CB. Patients with at least one detectable CTC at T1 (n = 26) had a worse PFS than those with 0 CTCs (n = 16) (p = 0.02). At T1, patients with an increase of at least three CTCs showed reduced PFS compared to those with no increase (mPFS = 3 versus 9 months, (p = 0.004). Finally, patients with ≥ 5 CTCs at T2 (n = 6/23) who received chemotherapy as post-study treatment had a shorter TTF (p = 0.02). Gene expression data for RB1 were obtained from 19 patients. CTCs showed heterogeneous RB1 expression. Patients with detectable expression of RB1 at any timepoint showed better, but not statistically significant, outcomes than those with undetectable levels. CONCLUSIONS: CTC count seems to be a promising modality in monitoring palbociclib response. Moreover, CTC count at the time of progression could predict clinical outcome post-palbociclib. RB1 expression analysis on CTCs is feasible and may provide additional prognostic information. Results should be interpreted with caution given the small studied sample size.

Systemic therapy for early breast cancer in older adults: current status and prospects.

PURPOSE OF REVIEW: In this review, we describe the evidence on the efficacy and the safety of systemic treatments for the management of early breast cancer (EBC) in older individuals. RECENT FINDINGS: Chemotherapy has a temporary impact on quality of life (QoL) for older EBC patients and improves survival outcomes for those with oestrogen receptor (ER)-negative disease. Benefits were seen also in the context of comorbidities, although these may be influenced by selection bias. The Cancer and Aging Research Group-Breast Cancer tool can predict the risk of severe toxicities on chemotherapy in older patients. Gene expression profiling is less frequently used in older adults although it holds promise to better inform patient selection also in this age group.Postneoadjuvant systemic therapy and novel agents remain poorly described in older patients with EBC. No disease-free survival benefits were seen in older patients receiving abemaciclib plus adjuvant endocrine therapy. SUMMARY: Chemotherapy is beneficial for selected older patients with high-risk, ER-negative EBC. Although its impact on QoL is temporary, preferences, higher risk of toxicity and competing risks need to be carefully considered. Open questions remain on novel therapeutic approaches and gene expression profile in older EBC patients and more real-world evidence is warranted.

Precision Oncology via NMR-Based Metabolomics: A Review on Breast Cancer.

Precision oncology is an emerging approach in cancer care. It aims at selecting the optimal therapy for the right patient by considering each patient's unique disease and individual health status. In the last years, it has become evident that breast cancer is an extremely heterogeneous disease, and therefore, patients need to be appropriately stratified to maximize survival and quality of life. Gene-expression tools have already positively assisted clinical decision making by estimating the risk of recurrence and the potential benefit from adjuvant chemotherapy. However, these approaches need refinement to further reduce the proportion of patients potentially exposed to unnecessary chemotherapy. Nuclear magnetic resonance (NMR) metabolomics has demonstrated to be an optimal approach for cancer research and has provided significant results in BC, in particular for prognostic and stratification purposes. In this review, we give an update on the status of NMR-based metabolomic studies for the biochemical characterization and stratification of breast cancer patients using different biospecimens (breast tissue, blood serum/plasma, and urine).

EFFECT: a randomized phase II study of efficacy and impact on function of two doses of nab-paclitaxel as first-line treatment in older women with advanced breast cancer.

BACKGROUND: Limited data are available regarding the use of nab-paclitaxel in older patients with breast cancer. A weekly schedule is recommended, but there is a paucity of evidence regarding the optimal dose. We evaluated the efficacy of two different doses of weekly nab-paclitaxel, with a specific focus on their corresponding impact on patient function, in order to address the lack of data specifically relating to the older population. METHODS: EFFECT is an open-label, phase II trial wherein 160 women with advanced breast cancer aged ≥ 65 years were enrolled from 15 institutions within Italy. Patients were randomly assigned 1:1 to receive nab-paclitaxel 100 mg/m2 (arm A) or 125 mg/m2 (arm B) on days 1, 8, and 15 on a 28-day cycle, as first-line treatment for advanced disease. The primary endpoint was event-free survival (EFS), wherein an event was defined as disease progression (PD), functional decline (FD), or death. In each arm, the null hypothesis that the median EFS would be ≤ 7 months was tested against a one-sided alternative according to the Brookmeyer Crowley test. Secondary endpoints included objective response rate (ORR), clinical benefit rate (CBR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS: After a median follow-up of 32.6 months, 140 events were observed in 158 evaluable patients. Median EFS was 8.2 months (90% CI, 5.9-8.9; p = 0.188) in arm A vs 8.3 months (90% CI, 6.2-9.7, p = 0.078) in arm B. Progression-free survival, overall survival, and response rates were similar in both groups. A higher percentage of dose reductions and discontinuations due to adverse events (AEs) was noted in arm B. The most frequently reported non-haematological AEs were fatigue (grade [G] 2-3 toxicity occurrence in arm A vs B, 43% and 51%, respectively) and peripheral neuropathy (G2-3 arm A vs B, 19% and 38%, respectively). CONCLUSION: Pre-specified outcomes were similar in both treatment arms. However, 100 mg/m2 was significantly better tolerated with fewer neurotoxicity-related events, representing a more feasible dose to be recommended for older patients with advanced disease. TRIAL REGISTRATION: EudraCT, 2012-002707-18 . Registered on June 4, 2012. NIH ClinicalTrials.gov, NCT02783222 . Retrospectively registered on May 26, 2016.

Correction: Quality of life under extended continuous versus intermittent adjuvant letrozole in lymph node-positive, early breast cancer patients: the SOLE randomised phase 3 trial.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Endocrine therapy for hormone receptor-positive, HER2-negative metastatic breast cancer: extending endocrine sensitivity.

Targeted agents have significantly prolonged survival and improved response rates in first- and second-line settings of hormone receptor-positive/HER2-negative metastatic breast cancer. Optimal sequencing of the available options may prolong endocrine sensitivity, slow disease progression and delay the need for chemotherapy. However, the optimal treatment sequence remains unclear and therapeutic decisions are complex. We review the latest recommendations and supporting evidence for endocrine therapy in women with hormone receptor-positive/HER2-negative metastatic breast cancer and discuss strategies for the optimal sequential therapy in scenarios of response to endocrine therapy. Although more data are needed to define the best sequence of endocrine treatments, more personalized sequential strategies, which take into account response to previous treatments as well as disease symptoms and safety issues, will be increasingly feasible.

Pembrolizumab plus trastuzumab in trastuzumab-resistant, advanced, HER2-positive breast cancer (PANACEA): a single-arm, multicentre, phase 1b-2 trial.

BACKGROUND: HER2-positive breast cancers usually contain large amounts of T-cell infiltrate. We hypothesised that trastuzumab resistance in HER2-positive breast cancer could be mediated by immune mechanisms. We assessed the safety and anti-tumour activity of pembrolizumab, a programmed cell death protein 1 (PD-1) inhibitor, added to trastuzumab in trastuzumab-resistant, advanced HER2-positive breast cancer. METHODS: We did this single-arm, multicentre, phase 1b-2 trial in 11 centres based in five countries. Eligible participants were women aged 18 years or older, who had advanced, histologically confirmed, HER2-positive breast cancer; documented progression during previous trastuzumab-based therapy; an Eastern Cooperative Oncology Group performance status of 0 or 1; and a formalin-fixed, paraffin-embedded metastatic tumour biopsy for central assessment of programmed cell death 1 ligand 1 (PD-L1) status. In phase 1b, we enrolled patients with PD-L1-positive tumours in a 3 + 3 dose-escalation of intravenous pembrolizumab (2 mg/kg and 10 mg/kg, every 3 weeks) plus 6 mg/kg of intravenous trastuzumab. The primary endpoint of the phase 1b study was the incidence of dose-limiting toxicity and recommended phase 2 dose; however, a protocol amendment on Aug 28, 2015, stipulated a flat dose of pembrolizumab of 200 mg every 3 weeks in all Merck-sponsored trials. In phase 2, patients with PD-L1-positive and PD-L1-negative tumours were enrolled in parallel cohorts and received the flat dose of pembrolizumab plus standard trastuzumab. The primary endpoint of the phase 2 study was the proportion of PD-L1-positive patients achieving an objective response. This trial is registered in ClinicalTrials.gov, number NCT02129556, and with EudraCT, number 2013-004770-10, and is closed. FINDINGS: Between Feb 2, 2015, and April 5, 2017, six patients were enrolled in phase 1b (n=3 received 2 mg/kg pembrolizumab, n=3 received 10 mg/kg pembrolizumab) and 52 patients in phase 2 (n=40 had PD-L1-positive tumours, n=12 had PD-L1-negative tumours). The data cutoff for this analysis was Aug 7, 2017. During phase 1b, there were no dose-limiting toxicities in the dose cohorts tested. Median follow-up for the phase 2 cohort was 13·6 months (IQR 11·6-18·4) for patients with PD-L1-positive tumours, and 12·2 months (7·9-12·2) for patients with PD-L1-negative tumours. Six (15%, 90% CI 7-29) of 40 PD-L1-positive patients achieved an objective response. There were no objective responders among the PD-L1-negative patients. The most common treatment-related adverse event of any grade was fatigue (12 [21%] of 58 patients). Grade 3-5 adverse events occurred in 29 (50%) of patients, treatment-related grade 3-5 adverse events occurred in 17 (29%), and serious adverse events occurred in 29 (50%) patients. The most commonly occurring serious adverse events were dyspnoea (n=3 [5%]), pneumonitis (n=3 [5%]), pericardial effusion (n=2 [3%]), and upper respiratory infection (n=2 [3%]). There was one treatment-related death due to Lambert-Eaton syndrome in a PD-L1-negative patient during phase 2. INTERPRETATION: Pembrolizumab plus trastuzumab was safe and showed activity and durable clinical benefit in patients with PD-L1-positive, trastuzumab-resistant, advanced, HER2-positive breast cancer. Further studies in this breast cancer subtype should focus on a PD-L1-positive population and be done in less heavily pretreated patients. FUNDING: Merck, International Breast Cancer Study Group.

Clinical outcomes after palbociclib with or without endocrine therapy in postmenopausal women with hormone receptor positive and HER2-negative metastatic breast cancer enrolled in the TREnd trial.

Currently, there is limited data regarding the effectiveness of standard subsequent line therapies such as endocrine therapy, chemotherapy, or targeted agents after progression on CDK4/6 inhibitor-based regimens. This paper describes time-to-treatment failure beyond progression on palbociclib or palbociclib+endocrine therapy in patients enrolled in the phase II, multicenter TREnd trial. Our results indicate that there is limited benefit from post-palbociclib treatment, regardless of the type of therapy received. A small population of long responders were identified who demonstrated ongoing benefit from a subsequent line of endocrine therapy after progression to palbociclib-based regimens. A translational research program is ongoing on this population of outliers.

Quality of life under extended continuous versus intermittent adjuvant letrozole in lymph node-positive, early breast cancer patients: the SOLE randomised phase 3 trial.

BACKGROUND: In the phase III SOLE trial, the extended use of intermittent versus continuous letrozole for 5 years did not improve disease-free survival in postmenopausal women with hormone receptor-positive breast cancer. Intermittent therapy with 3-month breaks may be beneficial for patients' quality of life (QoL). METHODS: In the SOLE QoL sub-study, 956 patients completed the Breast Cancer Prevention Trial (BCPT) symptom and further QoL scales up to 24 months after randomisation. Differences in change of QoL from baseline between the two administration schedules were tested at 12 and 24 months using repeated measures mixed-models. The primary outcome was change in hot flushes at 12 months. RESULTS: There was no difference in hot flushes at 12 months between the two schedules, but patients receiving intermittent letrozole reported significantly more improvement at 24 months. They also indicated less worsening in vaginal problems, musculoskeletal pain, sleep disturbance, physical well-being and mood at 12 months. Overall, 25-30% of patients reported a clinically relevant worsening in key symptoms and global QoL. CONCLUSION: Less symptom worsening was observed during the first year of extended treatment with the intermittent administration. For women experiencing an increased symptom burden of extended adjuvant endocrine therapy, an intermittent administration is a safe alternative. CLINICAL TRIAL INFORMATION: Clinical trial information: NCT00651456.

Eribulin Mesylate as Third or Subsequent Line Chemotherapy for Elderly Patients with Locally Recurrent or Metastatic Breast Cancer: A Multicentric Observational Study of GIOGer (Italian Group of Geriatric Oncology)-ERIBE.

BACKGROUND: Metastatic breast cancer (MBC) is highly prevalent in middle-aged or elderly patients. Eribulin is a nontaxane microtubule inhibitor, approved for the treatment of pretreated MBC. This multicentric study (sponsored by GIOGer, Italian Group for Geriatric Oncology) was designed to assess the efficacy and tolerability of eribulin, according to parameters usually used in geriatric oncology. SUBJECTS, MATERIALS, AND METHODS: An observational study was conducted on 50 consecutive elderly patients with MBC. The primary endpoint was to evaluate the change in items score of comprehensive geriatric assessment (CGA) and health-related quality of life (HRQL). Italian versions of the CGA and HRQL questionnaires were administered at baseline, before the third and fifth cycles, and then every three cycles until treatment discontinuation. Secondary endpoints were efficacy and safety. RESULTS: Overall, both EQ-5D scores and EQ-5D-3 L visual analogic scale did not significantly change from baseline; the percentage of subjects without problems doing usual activities tended to decrease during treatment (p for linear trend .018), and the percentage of patients with minor problems performing usual activities tended to increase (p for linear trend.012). Among CGA items, Instrumental Activities of Daily Living tended to decrease during treatment and Geriatric Depression Scale tended to increase. After 12 months follow-up, 24 patients (out of 47) showed clinical benefits; median progression-free survival was 4.49 months (2.10-10.33) and median OS was 7.31 months (3.70-14.03). The treatment was associated with mild toxicity. CONCLUSION: Eribulin treatment preserved quality of life and geriatric parameters included in the CGA, except for instrumental functioning and geriatric depression, in elderly patients with MBC. IMPLICATIONS FOR PRACTICE: A collaboration between oncologist and geriatric specialists is essential in the management of patients with metastatic breast cancer, who are frequently elderly or frail. The assessment of geriatric parameters in the decision-making process can contribute to direct toward the most appropriate therapeutic plan and preserve the quality of life of patients. Eribulin does not seem to affect quality of life or worsen the overall geriatric status; therefore, it can be considered a suitable option for elderly patients with metastatic breast cancer.

Early triple negative breast cancer: Are we getting better outcomes? A retrospective analysis from a single institution.

Overall survival (OS), disease-free survival (DFS), and distant recurrence-free interval (DRFI) were evaluated from 169 patients diagnosed with early triple negative breast cancer. Overall, 5 and 10 years OS, DFS, and DRFI were 77% and 65%; 60% and 46%; and 74% and 73%, respectively. Forty-seven patients did not receive chemotherapy. A separate analysis was performed excluding those patients. In this subgroup, 5- and 10-year OS, DFS, and DRFI were 86% and 77%; 68% and 54%, 77% both at 5 and 10 years. Prognosis is better than previously described; adjuvant chemotherapy should be offered to fit elderly patients if clinically warranted.

A gene expression signature of Retinoblastoma loss-of-function predicts resistance to neoadjuvant chemotherapy in ER-positive/HER2-positive breast cancer patients.

PURPOSE: HER2-positive (HER2+) breast cancers show heterogeneous response to chemotherapy, with the ER-positive (ER+) subgroup deriving less benefit. Loss of retinoblastoma tumor suppressor gene (RB1) function has been suggested as a cardinal feature of breast cancers that are more sensitive to chemotherapy and conversely resistant to CDK4/6 inhibitors. We performed a retrospective analysis exploring RBsig, a gene signature of RB loss, as a potential predictive marker of response to neoadjuvant chemotherapy in ER+/HER2+ breast cancer patients. METHODS: We selected clinical trials of neoadjuvant chemotherapy ± anti-HER2 therapy in HER2+ breast cancer patients with available information on gene expression data, hormone receptor status, and pathological complete response (pCR) rates. RBsig expression was computed in silico and correlated with pCR. RESULTS: Ten studies fulfilled the inclusion criteria and were included in the analysis (514 patients). Overall, of 211 ER+/HER2+ breast cancer patients, 49 achieved pCR (23%). The pCR rate following chemotherapy ± anti-HER2 drugs in patients with RBsig low expression was significantly lower compared to patients with RBsig high expression (16% vs. 30%, respectively; Fisher's exact test p = 0.015). The area under the ROC curve (AUC) was 0.62 (p = 0.005). In the 303 ER-negative (ER-)/HER2+ patients treated with chemotherapy ± anti-HER2 drugs, the pCR rate was 43%. No correlation was found between RBsig expression and pCR rate in this group. CONCLUSIONS: Low expression of RBsig identifies a subset of ER+/HER2+ patients with low pCR rates following neoadjuvant chemotherapy ± anti-HER2 therapy. These patients may potentially be spared chemotherapy in favor of anti-HER2, endocrine therapy, and CDK 4/6 inhibitor combinations.

An Italian Delphi study to evaluate consensus on adjuvant endocrine therapy in premenopausal patients with breast cancer: the ERA project.

BACKGROUND: Several trials evaluated the role of ovarian function suppression for the adjuvant treatment of premenopausal patients with hormone receptor-positive early breast cancer. Based on the results of the SOFT and TEXT trials, international guidelines recommend the addition of ovarian function suppression to standard adjuvant endocrine therapy for patients at higher risk of relapse. METHODS: The ERA project (Evaluation of Risk factors in the Adjuvant treatment of breast cancer in premenopausal patients) was devised with the objective of obtaining a consensus on the identification of risk factors and the use of ovarian function suppression in the adjuvant treatment of these women. To this aim, a panel of 31 Italian oncologists with expertise in breast cancer participated in a Delphi consensus study in June 2017. RESULTS: A total of 29 statements related to prognostic factors, therapeutic strategies and ovarian function suppression were defined and voted to gain final consensus. For each topic we report data supporting the acquired consensus and the relevant issues discussed. CONCLUSIONS: The SOFT and TEXT trials have changed the standard adjuvant treatment of premenopausal patients with hormone receptor-positive early breast cancer, but the available treatment options require a careful risk assessment and toxicities evaluation to ensure the greatest clinical benefit for each patient.

Continued value of adjuvant anthracyclines as treatment for early breast cancer.

Anthracyclines are frequently used in the adjuvant treatment of early-stage breast cancer. However, with the increasing use of other active drugs--mainly taxanes and trastuzumab in HER2-positive disease--coupled with concerns about anthracycline-associated toxic effects, there is debate about whether anthracyclines are still needed. Three major factors should be taken into consideration with the investigation of the role of anthracyclines in management of early breast cancer; specifically, the proven efficacy of anthracyclines in breast cancer, the absence of superiority of non-anthracycline-based chemotherapy over anthracycline-taxane regimens, and the low risk of toxic effects associated with the cumulative doses of anthracyclines used in contemporary regimens. The risks remain substantially outweighed by the benefits of treatment with anthracyclines, and thus, they maintain an important role in adjuvant treatment of breast cancer, particularly in women with high-risk disease.

Mutational Analysis of Circulating Tumor DNA in Patients With Estrogen Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer Receiving Palbociclib: Results From the TREnd Trial.

PURPOSE: To identify prognostic circulating biomarkers to cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i), we performed a mutational analysis on circulating tumor DNA (ctDNA) samples from patients included in the TREnd trial, which randomly assigned patients to receive the CDK4/6i palbociclib alone or with the endocrine treatment (ET) to which they had progressed. METHODS: Forty-six patients were enrolled in this substudy. Plasma was collected before treatment (T0), after the first cycle of therapy (T1), and at the time of progression (T2). ctDNA hybridization and capture were performed using the Illumina TruSight Tumor 170 Kit. Acquired mutations were confirmed by digital polymerase chain reaction. Progression-free survival analysis was estimated using the Kaplan-Meier method and compared with the log-rank test. RESULTS: The most frequently mutated genes at T0 were ESR1 (23%), PIK3CA (17%), AR, FGFR2, and TP53 (10%). Mutations in ESR1 at T0 conferred higher risk of progression in the entire population (P = .02) and in patients treated with palbociclib + ET (P = .04). ESR1 mutation effect remained significant after correction for clinical variables (P = .03). PIK3CA mutations at T0 were not prognostic, but higher risk of progression was observed when a broader analysis of PI3K pathway was performed (P = .04). At T2, we observed the emergence of nine new mutations in seven genes. CONCLUSION: Mutations in ESR1 and in PI3K pathway genes at T0 were associated with worse prognosis in palbociclib-treated patients. We describe the emergence of newly acquired mutations in palbociclib-treated patients, which might potentially affect subsequent treatment.

Adjuvant endocrine therapy choices in premenopausal patients with hormone receptor-positive early breast cancer: Insights from the prospective GIM23-POSTER study.

BACKGROUND: Most premenopausal patients with early breast cancer (eBC) are diagnosed with hormone receptor-positive disease and therefore candidate for adjuvant endocrine therapy (ET). PATIENTS AND METHODS: The Gruppo Italiano Mammella (GIM) 23-POSTER (GIM23) is a multicenter, prospective, observational study conducted in 26 Italian institutions, aiming to evaluate ET choices for premenopausal patients affected by hormone receptor-positive eBC in a real-world setting. Here we report also the results in terms of type of ET prescribed according to the definition of high-risk patients by monarchE and NATALEE trials. RESULTS: Between October 2019 and June 2022, 600 premenopausal patients were included, with a median age of 46 years. Almost half (271, 45.2 %) of the patients had stage I disease, while 254 (42.3 %) and 60 (10.0 %) patients had stage II and III, respectively. Overall, 149 (25.1 %) patients received tamoxifen alone, 83 (14.0 %) tamoxifen with ovarian function suppression (OFS), while 361 (60.9 %) received aromatase inhibitor (AI) with OFS. Patients treated with AI and OFS had higher number of metastatic axillary nodes, higher grade and more often received chemotherapy (all p < 0.001). According to the inclusion criteria of the monarchE and NATALEE trials, 81 patients (15.6 %) were considered high-risk for the monarchE and received AI with OFS in 88.9 % of the cases, while 231 patients (44.4 %) were considered high-risk for the NATALEE trial and received AI with OFS in 74.5 % of cases. CONCLUSIONS: AI with OFS is the most prescribed adjuvant ET among premenopausal patients, especially in the presence of high-risk features.

EUSOMA quality indicators for non-metastatic breast cancer: An update.

INTRODUCTION: Quality care in breast cancer is higher if patients are treated in a Breast Center with a dedicated and specialized multidisciplinary team. Quality control is an essential activity to ensure quality care, which has to be based on the monitoring of specific quality indicators. Eusoma has proceeded with the up-dating of the 2017 Quality indicators for non-metastatic breast cancer based on the new diagnostic, locoregional and systemic treatment modalities. METHODS: To proceed with the updating, EUSOMA setup a multidisciplinary working group of BC experts and patients' representatives. It is a comprehensive set of QIs for early breast cancer care, which are classified as mandatory, recommended, or observational. For the first time patient reported outcomes (PROMs) have been included. As used in the 2017 EUSOMA QIs, evidence levels were based on the short version of the US Agency for Healthcare Research and Quality. RESULTS: This is a set of quality indicators representative for the different steps of the patient pathway in non-metastatic setting, which allow Breast Centres to monitor their performance with referring standards, i.e minimum standard and target. CONCLUSIONS: Monitoring these Quality Indicators, within the Eusoma datacentre will allow to have a state of the art picture at European Breast Centres level and the development of challenging research projects.