An Overview of PARP Resistance in Ovarian Cancer from a Molecular and Clinical Perspective.

Epithelial ovarian cancer (EOC), a primarily high-grade serous carcinoma (HGSOC), is one of the major causes of high death-to-incidence ratios of all gynecological cancers. Cytoreductive surgery and platinum-based chemotherapy represent the main treatments for this aggressive disease. Molecular characterization of HGSOC has revealed that up to 50% of cases have a deficiency in the homologous recombination repair (HRR) system, which makes these tumors sensitive to poly ADP-ribose inhibitors (PARP-is). However, drug resistance often occurs and overcoming it represents a big challenge. A number of strategies are under investigation, with the most promising being combinations of PARP-is with antiangiogenetic agents and immune checkpoint inhibitors. Moreover, new drugs targeting different pathways, including the ATR-CHK1-WEE1, the PI3K-AKT and the RAS/RAF/MEK, are under development both in phase I and II-III clinical trials. Nevertheless, there is still a long way to go, and the next few years promise to be exciting.

TWIST1 Upregulation Is a Potential Target for Reversing Resistance to the CDK4/6 Inhibitor in Metastatic Luminal Breast Cancer Cells.

Cyclin-dependent kinase (CDK) 4/6 inhibitors have significantly improved progression-free survival in hormone-receptor-positive (HR+), human-epidermal-growth-factor-receptor-type-2-negative (HER2-) metastatic luminal breast cancer (mLBC). Several studies have shown that in patients with endocrine-sensitive or endocrine-resistant LBC, the addition of CDK4/6 inhibitors to endocrine therapy significantly prolongs progression-free survival. However, the percentage of patients who are unresponsive or refractory to these therapies is as high as 40%, and no reliable and reproducible biomarkers have been validated to select a priori responders or refractory patients. The selection of mutant clones in the target oncoprotein is the main cause of resistance. Other mechanisms such as oncogene amplification/overexpression or mutations in other pathways have been described in several models. In this study, we focused on palbociclib, a selective CDK4/6 inhibitor. We generated a human MCF-7 luminal breast cancer cell line that was able to survive and proliferate at different concentrations of palbociclib and also showed cross-resistance to abemaciclib. The resistant cell line was characterized via RNA sequencing and was found to strongly activate the epithelial-to-mesenchymal transition. Among the top deregulated genes, we found a dramatic downregulation of the CDK4 inhibitor CDKN2B and an upregulation of the TWIST1 transcription factor. TWIST1 was further validated as a target for the reversal of palbociclib resistance. This study provides new relevant information about the mechanisms of resistance to CDK4/6 inhibitors and suggests potential new markers for patients' follow-up care during treatment.

Conditioned Medium of Mesenchymal Stromal Cells Loaded with Paclitaxel Is Effective in Preclinical Models of Triple-Negative Breast Cancer (TNBC).

Triple-negative breast cancer (TNBC) is a very aggressive disease even in its early stages and is characterized by a severe prognosis. Neoadjuvant chemotherapy is one of the milestones of treatment, and paclitaxel (PTX) is among the most active drugs used in this setting. However, despite its efficacy, peripheral neuropathy occurs in approximately 20-25% of cases and represents the dose-limiting toxicity of this drug. New deliverable strategies to ameliorate drug delivery and reduce side effects are keenly awaited to improve patients' outcomes. Mesenchymal stromal cells (MSCs) have recently been demonstrated as promising drug delivery vectors for cancer treatment. The aim of the present preclinical study is to explore the possibility of a cell therapy approach based on the use of MSCs loaded with PTX to treat TNBC-affected patients. For this purpose, we in vitro evaluated the viability, migration and colony formation of two TNBC cell lines, namely, MDA-MB-231 and BT549, treated with MSC-PTX conditioned medium (MSC-CM PTX) in comparison with both CM of MSCs not loaded with PTX (CTRL) and free PTX. We observed stronger inhibitory effects on survival, migration and tumorigenicity for MSC-CM PTX than for CTRL and free PTX in TNBC cell lines. Further studies will provide more information about activity and potentially open the possibility of using this new drug delivery vector in the context of a clinical study.

The prolonged clinical benefit with metronomic chemotherapy (VEX regimen) in metastatic breast cancer patients.

Metronomic chemotherapy is a treatment option for metastatic breast cancer (MBC) patients who require prolonged disease control without cumulative toxicity. Data available on the efficacy and tolerability of prolonged usage of metronomic therapy are limited. We analyzed patients with MBC, enrolled in a clinical trial, who obtained a prolonged clinical benefit for a duration of at least 12 months with vinorelbine 30 or 40 mg orally three times a week, cyclophosphamide 50 mg daily and capecitabine 500 mg three times a day (VEX regimen). The patients were treated at the European Institute of Oncology, Milan. We identified 67 MBC patients. The median age before starting the VEX regimen was 53 years. There were 59 patients (88%) who had hormone-receptors positive and HER2 negative BC. We had 37 patients who received VEX as the first-line treatment for MBC, while 30 patients were pretreated. The objective response rate was 49% (95% CI, 37-62). The median duration of VEX treatment after the first year was 14 months (min-max range 0.3-81.3 months). The progression-free survival at 3 years was 25.4% (95% CI, 15.7-36.2) and at 4 years was 18.5% (95% CI, 10.1-28.8 time 0 corresponds to 1 year after starting VEX). A total of 25 patients required a dose reduction, 7% of patients experienced G3 hand and foot syndrome. Metronomic VEX regimen can induce prolonged clinical benefit in MBC. On the basis of this long-term safety evaluation, there is no evidence of specific cumulative or delayed toxicities with metronomic chemotherapy.

Why not? Motivations for entering a volunteer register for clinical trials during the COVID-19 pandemic.

BACKGROUNDS: Healthy volunteers play a key role in clinical trials and it is crucial to develop recruitment strategies that capitalise on their motivations and maximise their participation. The COVID-19 pandemic has shown the importance of finding motivated healthy volunteers for the development of new vaccines. Public registers represent a promising way to promote the participation of healthy volunteers in the research field, but their adoption is still limited. The current study aimed to explore the motivations of healthy volunteers to enrol in an Italian public register for clinical trials during the COVID-19 pandemic and their attitude toward participating in a phase 1 COVID-19 vaccine clinical trial. The impacts of different enrolling interview modalities (in person, by phone, by mail) on motivation, understanding of information and trust in researchers were also investigated. METHODS: An online survey investigating experience with COVID-19, motivations to enrol, trust in researchers, political and healthcare authorities and pharmacological companies was presented to people applying as healthy volunteers in the public register for clinical trials at Phase 1 Unit Research Centre of ASST Monza, Italy, and considering to participate in a COVID-19 vaccine clinical trial. Data were collected in June 2021. RESULTS: Altruistic motivations were the main driver for enrolling in the public register, while self-interested motivations were secondary. No gender differences were found. As for enrolling modalities, no differences emerged between in-person and interviews for motivation to enrol, understanding of information and trust in researchers. Email modality led to significantly lower volunteers' satisfaction and understanding of information but similar trust in research. CONCLUSIONS: This study supports the validity of different interview modalities (in person and by phone) for the enrolment of healthy volunteers for clinical trials and highlights the positive role of public registers for the recruitment procedures.

Social capital and willingness to participate in COVID-19 vaccine trials: an Italian case-control study.

BACKGROUND: What leads healthy people to enter in a volunteer register for clinical trials? This study aimed to investigate the relationship between the decision to volunteer in clinical trials for a COVID-19 vaccine and social capital, in a sample of healthy volunteers in Italy. Since social capital is characterized by trust, reciprocity, and social and political participation, we claim that it is key in leading individuals to actively take action to protect public health, and to take a risk for the (potential) benefit not only of themselves but for the entire community. METHODS: This study was conducted through the administration of a questionnaire to healthy volunteers registered for a phase 1 clinical trial for a COVID-19 vaccine in the Unit Research Centre of ASST-Monza, in September 2020. The primary purpose of a phase 1 study is to evaluate the safety of a new drug candidate before it proceeds to further clinical studies. To approximate a case-control study, we randomly matched the 318 respondents to healthy volunteers (cases) with 318 people randomly selected by Round 9 of the European Social Survey (controls), using three variables, which we considered to be associated with the decision to volunteer: gender, age, and education level. To execute this matching procedure, we used the "ccmatch" module in STATA. RESULTS: The findings highlight the positive impact of social capital in the choice of healthy individuals to volunteer in COVID-19 vaccine clinical trials. Controlling for possible confounding factors, some exemplary results show that people with a high level of general trust have a greater likelihood of volunteering compared to people with low trust (OR = 2.75, CI = 1.58-4.77); we also found that it is more probable that volunteers are people who have actively taken action to improve things compared with people who have not (for individuals who did three or more actions: OR = 7.54, CI = 4.10-13.86). People who reported voting (OR = 3.91, CI = 1.70-8.99) and participating in social activities more than other people of their age (OR = 2.89, CI = 1.82-4.60) showed a higher probability to volunteer. CONCLUSIONS: Together with the adoption of urgent health measures in response to COVID-19, government policymakers should also promote social capital initiatives to encourage individuals to actively engage in actions aimed at protecting collective health. Our findings make an empirical contribution to the research on vaccines and its intersection with social behaviour, and they provide useful insights for policymakers to manage current and future disease outbreaks and to enhance the enrolment in vaccine trials.

Fulvestrant and trastuzumab in patients with luminal HER2-positive advanced breast cancer (ABC): an Italian real-world experience (HERMIONE 9).

PURPOSE: The most appropriate therapy for HR + /HER2-positive (HER2 +) advanced breast cancer (ABC) is a matter of debate. Co-targeting of both receptors represents an attractive strategy to overcome the cross-talk between them. METHODS: The HERMIONE 9 is an observational retrospective multicentric study which aimed to describe the clinical outcome of patients with HR + /HER2 + ABC who received the combination of Fulvestrant (F) and Trastuzumab (T) as part of their routine treatment at 10 Italian Institutions. RESULTS: Eighty-seven patients were included. Median age was 63 (range, 35-87) years. The median number of previous treatments was 3 (range, 0-10) and F and T were administered as ≥ 3rd line in 67 patients. Among the 86 evaluable patients, 6 (6.9%) achieved CR, 18 (20.7%) PR, and 44 (50.6%) had SD ≥ 24 weeks with an overall CBR of 78.2%. At a median follow-up of 33.6 months, mPFS of the entire cohort was 12.9 months (range, 2.47-128.67). No difference was observed in mPFS between patients treated after progression or as maintenance therapy (mPFS 12.9 and 13.9 months in 64 and 23 patients, respectively), neither considering the number of previous treatment lines (≤ 3 or < 3). CONCLUSION: The combination of F and T was active in this cohort at poor prognosis and deserves further investigations possibly in combination with pertuzumab in patients with high ER expression.

Comparison of tumor microenvironment in primary and paired metastatic ER+/HER2- breast cancers: results of a pilot study.

BACKGROUND: Tumor microenvironment (TME) is a dynamic setting and changes in TILs and their subpopulations are potential candidates to influence the metastatic process. Aim of this pilot study is to describe the changes occurring between primary breast cancers and their paired metastases in terms of TILs composition. To assess if these changes influence the process of metastasis development, we used a control group of patients. METHODS: We retrospectively identified 18 Luminal patients, for whom primary and metastatic tissue were available (cases) and 18 paired-matched patients (controls), not relapsed after at least 9 years of follow-up, and we quantified TILs and their composition (i.e. T CD8+ and CD4+/FOXP3+). The presence of TILs was defined as ≥10%. RESULTS: Our results showed that the microenvironment composition of relapsed patients was poor of TILs (median = 5%, I-III quartiles = 0.6-5%), CD8+ (2.5%, 0-5%) and CD4+/FOXP3 + (0%, 0-0.6%) in the primary tumor. Comparable results were observed in their related metastases (TILs 3.8%, 0.6-5%; CD8+ 0%, 0-1.3%; CD4+/FOXP3+ 0%,0-1.9%). On the contrary, the microenvironment in the control group was richer of TILs (5%, 5-17.5%) in comparison to cases, both in primary tumor (p = 0.035) and related metastases (p = 0.018). Although CD8+ in controls were similar to cases at primary tumor (p = 0.6498), but not at metastasis (p = 0.0223), they expressed only one part on the TILs subpopulations (p = 0.0060), while TILs in the cases at primary tumor were almost completely CD8+ (p = 0.5034). CONCLUSIONS: These findings suggest that the lack of activation of immune system in the primary tumor might influence the multifactor process of cancer progression.

Validation of the Italian version of the full and abbreviated Trust in Oncologist Scale.

INTRODUCTION: The Trust in Oncologist Scale (TiOS) is an 18-item questionnaire aimed to assess the cancer patients' trust in their oncologist and has been validated in Dutch and English language. This study aims to validate the Italian version of the TiOS (IT-TiOS) and the TiOS-Short Form (IT-TiOS-SF). METHODS: The IT-TiOS was administered to 194 patients recruited in an Italian oncology department from April to December 2018. Data collected included socio-demographic data, health and clinical information, satisfaction with the most recent oncology visit and trust in the regional healthcare system. Internal consistency, test-retest reliability, convergent and the structural validity of both the full and short form were tested. RESULTS: Factor analyses indicated that neither four-factor nor one-factor models of the full scale were acceptable. However, confirmatory factor analysis supported the one-dimensionality of the IT-TiOS-SF, and internal consistency assessed with Cronbach's alpha was 0.88. Mean scores on the IT-TiOS-SF correlated with satisfaction with the oncologist (rs = 0.64) and willingness to recommend the oncologist to others (rs = 0.67), confirming good construct validity. CONCLUSION: The IT-TiOS-SF demonstrates good psychometric properties and can be used to assess trust for both clinical and research purposes.

Netupitant/palonosetron (NEPA) and dexamethasone for prevention of emesis in breast cancer patients receiving adjuvant anthracycline plus cyclophosphamide: a multi-cycle, phase II study.

BACKGROUND: NEPA is an oral fixed-dose combination of netupitant, a new highly selective neurokinin-1 receptor antagonist, and palonosetron. This study was conducted to evaluate whether the efficacy of NEPA against chemotherapy-induced nausea and vomiting (CINV) in cycle 1 would be maintained over subsequent chemotherapy cycles in breast cancer patients receiving adjuvant anthracycline plus cyclophosphamide (AC). The study also describes the relationship between efficacy on day 1 through 5 (overall period) and control of CINV on day 6 through 21 (very late period) in each cycle. METHODS: In this multicentre, phase II study, patients received both NEPA and dexamethasone (12 mg intravenously) just before chemotherapy. The primary efficacy endpoint was overall complete response (CR; no emesis and no rescue medication use) in cycle 1. Sustained efficacy was evaluated during the subsequent cycles by calculating the rate of CR in cycles 2-4 and by assessing the probability of sustained CR over multiple cycles. The impact of both overall CR and risk factors for CINV on the control of very late events (vomiting and moderate-to-severe nausea) were also examined. RESULTS: Of the 149 patients enrolled in the study, 139 were evaluable for a total of 552 cycles; 97.8% completed all 4 cycles. The proportion of patients with an overall CR was 70.5% (90% CI, 64.1 to 76.9) in cycle 1, and this was maintained in subsequent cycles. The cumulative percentage of patients with a sustained CR over 4 cycles was 53%. NEPA was well tolerated across cycles. In each cycle, patients with CR experienced a significantly better control of very late CINV events than those who experienced no CR. Among the patients with CR, the only predictor for increased likelihood of developing very late CINV was pre-chemotherapy (anticipatory) nausea (adjusted odds ratio = 0.65-0.50 for no CINV events on cycles 3 and 4). CONCLUSION: The high anti-emetic efficacy seen with the NEPA regimen in the first cycle was maintained over multiple cycles of adjuvant AC for breast cancer. Preliminary evidence also suggests that patients achieving a CR during the overall period gain high protection even against very late CINV events in each chemotherapy cycle. TRIAL REGISTRATION: This trial was retrospectively registered at Clinicaltrials.gov identifier (NCT03862144) on 05/Mar/2019.

Management of toxicities associated with targeted therapies for HR-positive metastatic breast cancer: a multidisciplinary approach is the key to success.

PURPOSE: Agents targeting HR-positive, HER2-negative locally advanced or metastatic breast cancer have improved patient outcomes compared with conventional single-agent endocrine therapy. Currently, approved targeted agents include everolimus and three CDK4/6 inhibitors, palbociclib, ribociclib, and abemaciclib. Unlike the well-characterized and easily manageable safety profile of endocrine therapies, adverse events associated with targeted therapies are complex and potentially severe. Their prompt recognition and treatment, crucial for prolonged endocrine sensitivity and survival, may be challenging and requires a multidisciplinary effort and a good knowledge of drug interactions. METHODS: We reviewed the current evidence on the drug safety of targeted agents for metastatic breast cancer currently used in clinical practice in Italy, supported by the clinical experience of Italian oncologists with expertise in the field. RESULTS: All oncologists had used CDK4/6 inhibitors in clinical practice and/or within a clinical trial. The clinical management of toxicities, including dose adjustments, treatment interruptions, and concerns regarding special populations is discussed, and the management of relevant adverse events, related to individual agents and class-specific, toxicities is reviewed. Hematologic toxicities have the greatest impact on clinical management of the disease and on patients. Although toxicities associated with the new treatments result in more visits to the physician and more time and attention with patients, they are manageable, with no need for the oncologist to consult with specialist physicians. CONCLUSIONS: Based on the available evidence and current guidelines, we propose a series of practical recommendations for multidisciplinary clinical management of the various toxicities associated with the addition of targeted agents to endocrine therapy.

Everolimus Plus Exemestane in Advanced Breast Cancer: Safety Results of the BALLET Study on Patients Previously Treated Without and with Chemotherapy in the Metastatic Setting.

BACKGROUND: The BALLET study was an open-label, multicenter, expanded access study designed to allow treatment with everolimus plus exemestane in postmenopausal women with hormone receptor-positive metastatic breast cancer progressed following prior endocrine therapy. A post hoc analysis to evaluate if previous chemotherapy in the metastatic setting affects the safety profile of the combination regimen of everolimus and exemestane was conducted on the Italian subset, as it represented the major part of the patients enrolled (54%). PATIENTS AND METHODS: One thousand one hundred and fifty-one Italian patients were included in the present post hoc analysis, which focused on two sets of patients: patients who never received chemotherapy in the metastatic setting (36.1%) and patients who received at least one chemotherapy treatment in the metastatic setting (63.9%). RESULTS: One thousand one hundred and sixteen patients (97.0%) prematurely discontinued the study drug, and the main reasons reported were disease progression (39.1%), local reimbursement of everolimus (31.1%), and adverse events (AEs) (16.1%). The median duration of study treatment exposure was 139.5 days for exemestane and 135.0 days for everolimus. At least one AE was experienced by 92.5% of patients. The incidence of everolimus-related AEs was higher (83.9%) when compared with those that occurred with exemestane (29.1%), and the most commonly reported everolimus-related AE was stomatitis (51.3%). However, no significant difference in terms of safety related to the combination occurred between patients without and with chemotherapy in the metastatic setting. CONCLUSION: Real-life data of the Italian patients BALLET-related cohort were an adequate setting to state that previous chemotherapy did not affect the safety profile of the combination regimen of everolimus and exemestane. IMPLICATIONS FOR PRACTICE: With the advent of new targeted agents for advanced or metastatic breast cancer, multiple lines of therapy may be possible, and components of the combined regimens can overlap from one line to another. Thus, it is important to assess even the potential of cumulative and additive toxic effects among the drugs. Previous chemotherapy did not affect the safety profile of the combination regimen of everolimus and exemestane. The continuous monitoring of the safety signals of this drug combination from general clinical practice is important, in particular for stomatitis.

Differential Expression of NOTCH-1 and Its Molecular Targets in Response to Metronomic Followed by Conventional Therapy in a Patient with Advanced Triple-Negative Breast Cancer.

A group of 27 patients diagnosed with metastatic triple-negative breast cancer (mTNBC) was randomly distributed into two groups and underwent different lines of metronomic treatment (mCHT). The former group (N 14) received first-line mCHT and showed a higher overall survival rate than the second group (N 13), which underwent second-line mCHT. Analysis of one patient still alive from the first group, diagnosed with mTNBC in 2019, showed a complete metabolic response (CMR) after a composite approach implicating first-line mCHT followed by second-line epirubicin and third-line nab-paclitaxel, and was chosen for subsequent molecular characterization. We found altered expression in the cancer stemness-associated gene NOTCH-1 and its corresponding protein. Additionally, we found changes in the expression of oncogenes, such as MYC and AKT, along with their respective proteins. Overall, our data suggest that a first-line treatment with mCHT followed by MTD might be effective by negatively regulating stemness traits usually associated with the emergence of drug resistance.

Low RNA disruption during neoadjuvant chemotherapy predicts pathologic complete response absence in patients with breast cancer.

In previously reported retrospective studies, high tumor RNA disruption during neoadjuvant chemotherapy predicted for post-treatment pathologic complete response (pCR) and improved disease-free survival at definitive surgery for primary early breast cancer. The BREVITY (Breast Cancer Response Evaluation for Individualized Therapy) prospective clinical trial (NCT03524430) seeks to validate these prior findings. Here we report training set (Phase I) findings, including determination of RNA disruption index (RDI) cut points for outcome prediction in the subsequent validation set (Phase II; 454 patients). In 80 patients of the training set, maximum tumor RDI values for biopsies obtained during neoadjuvant chemotherapy were significantly higher in pCR responders than in patients without pCR post-treatment (P = .008). Moreover, maximum tumor RDI values ≤3.7 during treatment predicted for a lack of pCR at surgery (negative predictive value = 93.3%). These findings support the prospect that on-treatment tumor RNA disruption assessments may effectively predict post-surgery outcome, possibly permitting treatment optimization.

Late onset toxicities associated with the use of CDK 4/6 inhibitors in hormone receptor positive (HR+), human epidermal growth factor receptor-2 negative (HER2-) metastatic breast cancer patients: a multidisciplinary, pan-EU position paper regarding their optimal management. The GIOCONDA project.

The personalization of therapies in breast cancer has favoured the introduction of new molecular-targeted therapies into clinical practice. Among them, cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitors have acquired increasing importance, with the approval in recent years of palbociclib, ribociclib, and abemaciclib in combination with endocrine therapy. Currently, no guidelines are available to monitor and manage potential long-term toxicities associated with the use of these drugs. A multidisciplinary panel of European oncologists, was supported by a pharmacologist, a hematologist, a hepatologist and a pulmonologist to discuss the management of long-term toxicities, based on the literature review and their clinical experience. The panel provided detailed roadmaps to manage long-term toxicities associated with the use of CDK4/6 inhibitors in clinical practice. Knowing the frequency and characteristics of the toxicity profile associated with each CDK4/6 inhibitor is important in the decision-making process to match the right drug to the right patient.

Clinical Outcomes of HER2-Negative Metastatic Breast Cancer Patients in Italy in the Last Decade: Results of the GIM 13-AMBRA Study.

GIM 13-AMBRA is a longitudinal cohort study aimed at describing therapeutic strategies and the relative outcome parameters in 939 HER2-ve MBC patients. Taxanes-based regimens, or taxanes + targeted agents, mainly Bevacizumab, were the preferred first choice in both Luminal (30.2%) and TNBC (33.3%) patients. The median PFS1 was 12.5 months (95% CI 16.79-19.64), without any significant difference according to subtypes, while the median Time to first Treatment Change (TTC1) was significantly lower in TNBC patients (7.7 months-95% CI 5.7-9.2) in comparison to Luminal A (13.2 months, 95% CI 11.7-15.1) and Luminal B patients (11.8 months, 95% CI 10.3-12.8). PFS2 was significantly shorter in TNBC patients (5.5 months, 95% CI 4.3-6.5 vs. Luminal A-9.4, 95% CI 8.1-10.7, and Luminal B-7.7 95% CI 6.8-8.2, F-Ratio 4.30, p = 0.014). TTC2 was significantly lower in patients with TNBC than in those with the other two subtypes. The median OS1 was 35.2 months (95% CI 30.8-37.4) for Luminal A patients, which was significantly higher than that for both Luminal B (28.9 months, 95% CI 26.2-31.2) and TNBC (18.5 months, 95% CI 16-20.1, F-ratio 7.44, p = 0.0006). The GIM 13-AMBRA study is one of the largest collections ever published in Italy and provides useful results in terms of time outcomes for first, second, and further lines of treatment in HER2- MBC patients.

Adjuvant capecitabine in triple negative breast cancer patients with residual disease after neoadjuvant treatment: real-world evidence from CaRe, a multicentric, observational study.

Background: In triple negative breast cancer patients treated with neoadjuvant chemotherapy, residual disease at surgery is the most relevant unfavorable prognostic factor. Current guidelines consider the use of adjuvant capecitabine, based on the results of the randomized CREATE-X study, carried out in Asian patients and including a small subset of triple negative tumors. Thus far, evidence on Caucasian patients is limited, and no real-world data are available. Methods: We carried out a multicenter, observational study, involving 44 oncologic centres. Triple negative breast cancer patients with residual disease, treated with adjuvant capecitabine from January 2017 through June 2021, were recruited. We primarily focused on treatment tolerability, with toxicity being reported as potential cause of treatment discontinuation. Secondarily, we assessed effectiveness in the overall study population and in a subset having a minimum follow-up of 2 years. Results: Overall, 270 patients were retrospectively identified. The 50.4% of the patients had residual node positive disease, 7.8% and 81.9% had large or G3 residual tumor, respectively, and 80.4% a Ki-67 >20%. Toxicity-related treatment discontinuation was observed only in 10.4% of the patients. In the whole population, at a median follow-up of 15 months, 2-year disease-free survival was 62%, 2 and 3-year overall survival 84.0% and 76.2%, respectively. In 129 patients with a median follow-up of 25 months, 2-year disease-free survival was 43.4%, 2 and 3-year overall survival 78.0% and 70.8%, respectively. Six or more cycles of capecitabine were associated with more favourable outcomes compared with less than six cycles. Conclusion: The CaRe study shows an unexpectedly good tolerance of adjuvant capecitabine in a real-world setting, although effectiveness appears to be lower than that observed in the CREATE-X study. Methodological differences between the two studies impose significant limits to comparability concerning effectiveness, and strongly invite further research.

Metronomic Chemotherapy for Metastatic Breast Cancer Treatment: Clinical and Preclinical Data between Lights and Shadows.

Metronomic chemotherapy (mCHT), defined as continuous administration of low-dose chemotherapeutic agents with no or short regular treatment-free intervals, was first introduced to the clinic in international guidelines in 2017, and, since then, has become one of the available strategies for the treatment of advanced breast cancer (ABC). Despite recent successes, many unsolved practical and theoretical issues remain to be addressed. The present review aims to identify the "lights and shadows" of mCHT in preclinical and clinical settings. In the preclinical setting, several findings indicate that one of the most noticeable effects of mCHT is on the tumor microenvironment, which, over the last twenty years, has been demonstrated to be pivotal in supporting tumor cell survival and proliferation. On the other hand, the direct effects on tumor cells have been less well-defined. In addition, critical items to be addressed are the lack of definition of an optimal biological dose (OBD), the method of administration of metronomic schedules, and the recognition and validation of predictive biomarkers. In the clinical context-where mCHT has mainly been used in a metastatic setting-low toxicity is the most well-recognised light of mCHT, whereas the type of study design, the absence of randomised trials and uncertainty in terms of doses and drugs remain among the shadows. In conclusion, growing evidence indicates that mCHT is a suitable treatment option for selected metastatic breast cancer (MBC) patients. Moreover, given its multimodal mechanisms of action, its addition to immunological and targeted therapies might represent a promising new approach to the treatment of MBC. More preclinical data are needed in this regard, which can only be obtained through support for translational research as the key link between basic science and patient care.

Personalised Therapies for Metastatic Triple-Negative Breast Cancer: When Target Is Not Everything.

Triple-negative breast cancer-defined by the absence of oestrogen/progesterone receptors and human epidermal growth factor receptor 2 expression-is a complex and heterogeneous type of tumour characterised by poor prognosis, aggressive behaviour and lack of effective therapeutic strategies. The identification of new biomarkers and molecular signatures is leading to development of new therapeutic strategies including immunotherapy, targeted therapy and antibody-drug conjugates (ADCs). Against a background where chemotherapy has always been considered the standard of care, evolution towards a precision medicine approach could improve TNBC clinical practice in a complex scenario, with many therapeutic options and new drugs. The aim of this review was to focus on emerging therapeutic targets and their related specific therapy, discussing available and emerging drugs, underlining differences in approval by American and European regulatory authorities and showing the future perspective in the large number of ongoing clinical trials.

How to Treat HR+/HER2- Metastatic Breast Cancer Patients after CDK4/6 Inhibitors: An Unfinished Story.

CDK4/6 inhibitors in association with endocrine therapy represent the best therapeutic choice for either endocrine-sensitive or resistant hormone-receptor-positive advanced breast cancer patients. On the contrary, the optimal therapeutic strategy after the failure of CDK4/6 inhibitors-based treatment still remains an open question worldwide. In this review, we analyze the most studied mechanisms of resistance to CDK4/6 inhibitors treatment, as well as the most significant results of retrospective and prospective trials in the setting of progression after CDK4/6 inhibitors, to provide the reader a comprehensive overview from both a preclinical and especially a clinical perspective. In our opinion, an approach based on a deeper knowledge of resistance mechanisms to CDK4/6 inhibitors, but also on a careful analysis of what is done in clinical practice, can lead to a better definition of prospective randomized trials, to implement a personalized sequence approach, based on molecular analyses.