Triple negative breast cancer: new perspectives for targeted therapies

Breast cancer is a heterogeneous disease, encompassing a large number of entities showing different morphological features and having clinical behaviors. It has became apparent that this diversity may be justified by distinct patterns of genetic, epigenetic, and transcriptomic aberrations. The identification of gene-expression microarray-based characteristics has led to the identification of at least five breast cancer subgroups: luminal A, luminal B, normal breast-like, human epidermal growth factor receptor 2, and basal-like. Triple-negative breast cancer is a complex disease diagnosed by immunohistochemistry, and it is characterized by malignant cells not expressing estrogen receptors or progesterone receptors at all, and human epidermal growth factor receptor 2. Along with this knowledge, recent data show that triple-negative breast cancer has specific molecular features that could be possible targets for new biological targeted drugs. The aim of this article is to explore the use of new drugs in this particular setting, which is still associated with poor prognosis and high risk of distant recurrence and death

Efficacy of Neoadjuvant Carboplatin plus Docetaxel in Triple-Negative Breast Cancer: Combined Analysis of Two Cohorts

Recent studies demonstrate that addition of neoadjuvant (NA) carboplatin (Cb) to anthracycline/taxane chemotherapy improves pathological complete response (pCR) in triple negative breast cancer (TNBC). Effectiveness of anthracycline-free, platinum combinations in TNBC is not well known. Here we report efficacy of NA carboplatin + docetaxel (CbD) in TNBC

Neoadjuvant treatments in triple-negative breast cancer patients: where we are now and where we are going

Abstract: Triple-negative breast cancer (TNBC) remains the poorest-prognosis breast cancer (BC) subtype. Gene expression profiling has identified at least six different triple-negative subtypes with different biology and sensitivity to therapies. The heterogeneous nature of TN tumors may justify the difficulty in treating this BC subtype. Several targeted agents have been investigated in clinical trials without demonstrating a clear survival benefit. Therefore, systemic chemotherapy remains the cornerstone of current clinical practice. Improving the knowledge of tumor biology is mandatory for patient management. In stages II and III, neoadjuvant systemic treatment is an effective option of care. The achievement of a pathological complete response represents an optimal surrogate for survival outcome as well as a test for tumor drug sensitivity. In this review, we provide a brief description of the main predictive biomarkers for tumor response to systemic treatment. Moreover, we review the treatment strategies investigated for TNBCs in neoadjuvant settings focusing on experimental drugs such as immunotherapy and poly [ADP-ribose] polymerase inhibitors that hold promise in the treatment of this aggressive disease. Therefore, the management of TNBC represents an urgent, current, unmet need in daily clinical practice. A key recommendation is to design biology-driven clinical trials wherein TNBC patients may be treated on the basis of tumor molecular profile

Neoadjuvant approach as a platform for treatment personalization: focus on HER2-positive and triple-negative breast cancer.

The neoadjuvant setting provides unquestionable clinical benefits for high-risk breast cancer (BC) patients, mainly in terms of expansion of locoregional treatment options and prognostic stratification. Additionally, it is also emerging as a strategical tool in the research field. In the present review, by focusing on HER2-positive and triple-negative subtypes, we examined the role of the neoadjuvant setting as a research platform to facilitate and rationalize the placement of escalation strategies, promote the adoption of biomarker-driven approaches for the investigation of de-escalated treatments, and foster the conduction of comprehensive translational analyses, thus ultimately aiming at pursuing treatment personalization. The solid prognostic role of pathologic complete response after neoadjuvant therapy, and its use as a surrogate endpoint to accelerate the drug approval process were discussed. In this context, available data on escalated treatment strategies capable of enhancing pathologic complete response (pCR) rate or improving prognosis of patients with residual disease (RD) after neoadjuvant treatment, were comprehensively reviewed. We also summarized evidence regarding the possibility of obtaining pCR with de-escalated strategies, with particular emphasis on the role of biomarker-driven approaches for patient selection. Pitfalls of the dichotomy of pCR/RD were also deepened, and data on alternative/complementary biomarkers with a possible clinical relevance in this regard were reviewed

Recent Advances in the Neoadjuvant Treatment of Breast Cancer

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Platinum-based neoadjuvant chemotherapy in triple-negative breast cancer: a systematic review and meta-analysis

Background: The role of platinum-based neoadjuvant chemotherapy in triple-negative breast cancer (TNBC) patients is highly controversial and it is not endorsed by current guidelines. Our meta-analysis aimed to better elucidate its activity, efficacy and safety. Material and methods: A systematic search of Medline, Web of Science and conferences proceedings up to 30 October 2017 was carried out to identify randomized controlled trials (RCTs) investigating platinum-based versus platinum-free neoadjuvant chemotherapy in TNBC patients. Using the fixed and random effects models, pooled odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CI) were calculated for pathological complete response (pCR, defined as ypT0/is pN0), event-free survival (EFS), overall survival (OS) and grade 3 and 4 adverse events (AEs: neutropenia, anemia, thrombocytopenia and neuropathy). Results: Nine RCTs (N \ubc 2109) were included. Overall, platinum-based neoadjuvant chemotherapy significantly increased pCR rate from 37.0% to 52.1% (OR 1.96, 95% CI 1.46\u20132.62, P < 0.001). Platinum-based neoadjuvant chemotherapy remained significantly associated with increased pCR rate also after restricting the analysis to the three RCTs (N \ubc 611) that used the same standard regimen in both groups of weekly paclitaxel (with or without carboplatin) followed by anthracycline and cyclophosphamide (OR 2.53, 95% CI 1.37\u20134.66, P \ubc 0.003). Conversely, among the 96 BRCA-mutated patients included in two RCTs, the addition of carboplatin was not associated with significantly increased pCR rate (OR 1.17, 95% CI 0.51\u20132.67, P \ubc 0.711). Two RCTs (N \ubc 748) reported survival outcomes: no significant difference in EFS (HR 0.72, 95% CI 0.49\u20131.06, P \ubc 0.094) and OS (HR 0.86, 95% CI 0.46\u20131.63, P \ubc 0.651) was observed. A significant higher risk of grade 3 and 4 hematological AEs, with no increased risk of grade 3 and 4 neuropathy was observed with platinum-based neoadjuvant chemotherapy. Conclusion: In TNBC patients, platinum-based neoadjuvant chemotherapy is associated with significantly increased pCR rates at the cost of worse hematological toxicities. Platinum-based neoadjuvant chemotherapy may be considered an option in TNBC patients

A randomized phase 2 study of neoadjuvant carboplatin and paclitaxel with or without atezolizumab in triple negative breast cancer (TNBC) - NCI 10013

Atezolizumab with chemotherapy has shown improved progression-free and overall survival in patients with metastatic PD-L1 positive triple negative breast cancer (TNBC). Atezolizumab with anthracycline- and taxane-based neoadjuvant chemotherapy has also shown increased pathological complete response (pCR) rates in early TNBC. This trial evaluated neoadjuvant carboplatin and paclitaxel with or without atezolizumab in patients with clinical stages II-III TNBC. The co-primary objectives were to evaluate if chemotherapy and atezolizumab increase pCR rate and tumor infiltrating lymphocyte (TIL) percentage compared to chemotherapy alone in the mITT population. Sixty-seven patients (ages 25-78 years; median, 52 years) were randomly assigned - 22 patients to Arm A, and 45 to Arm B. Median follow up was 6.6 months. In the modified intent to treat population (all patients evaluable for the primary endpoints who received at least one dose of combination therapy), the pCR rate was 18.8% (95% CI 4.0-45.6%) in Arm A, and 55.6% (95% CI 40.0-70.4%) in Arm B (estimated treatment difference: 36.8%, 95% CI 8.5-56.6%; p = 0.018). Grade 3 or higher treatment-related adverse events occurred in 62.5% of patients in Arm A, and 57.8% of patients in Arm B. One patient in Arm B died from recurrent disease during the follow-up period. TIL percentage increased slightly from baseline to cycle 1 in both Arm A (mean ± SD: 0.6% ± 21.0%) and Arm B (5.7% ± 15.8%) (p = 0.36). Patients with pCR had higher median TIL percentages (24.8%) than those with non-pCR (14.2%) (p = 0.02). Although subgroup analyses were limited by the small sample size, PD-L1-positive patients treated with chemotherapy and atezolizumab had a pCR rate of 75% (12/16). The addition of atezolizumab to neoadjuvant carboplatin and paclitaxel resulted in a statistically significant and clinically relevant increased pCR rate in patients with clinical stages II and III TNBC. (Funded by National Cancer Institute)

Management of triple negative breast cancer

Triple negative breast cancer (TNBC) accounts for approximately 15% of breast cancer cases. TNBC is an immunohistochemically defined subtype, with significant diversity within the subtype. Generally TNBC occurs in younger women and is marked by high rates of relapse, visceral and CNS metastases, and early death. Current therapy fails to curtail the innate aggressive behaviour of TNBC in the majority of patients. The poor prognosis coupled with a lack of targeted use of therapies is reflected in the high mortality. In a minority of patients with highly chemosensitive disease, no robust clinical evidence exists to guide use of current cytotoxics. Critical to optimal future management are accurate identification of truly triple negative disease and adequately powered prospective TNBC trials to establish treatment efficacy and define predictive biomarkers

RESPONSE TO NEOADJUVANT THERAPY AND LONG-TERM OUTCOME IN PATIENTS WITH TRIPLE NEGATIVE BREAST CANCER

Background. Triple negative breast cancer (TNBC) is defined by thelack of estrogen receptors (ER), progesterone receptors (PR) and humanepidermal growth factor receptor 2 (HER-2) expression. In this study weinvestigated response to neoadjuvant chemotherapy in TNBC patients and itsimpact on disease free (DFS) and overall survival (OS).Patients and methods. We identified 134 patients with stage I-III TNBCtreated at Riga East University Hospital between 2009-2012. 48 patients withTNBC received neoadjuvant chemotherapy. Correlation of clinical andpathological parameters with pathologic complete response (pCR) rate,disease-free and overall survival measurements and organ specific relapserates were analysed.Results. 48 patients with stage IIB-IIIC TNBC were included, 17 patientsreceived anthracycline based, 31 patients anthracycline and taxane basedneoadjuvant chemotherapy. 8 patients (16%) had pCR, 38 patients hadincomplete response, 2 patients had disease progression during neoadjuvantchemotherapy. pCR correlates with primary tumor size, but not with otherclinical and pathological factors. At a median follow-up of 30 months, 100%patients who reached pCR were disease-free versus 55% in those withoutpCR (p=0.017). Overall survival was 100% in patients who had pCR versus50% in those without pCR (p=0.020). 2 patients are alive after diseaserecurrence, 20 patients died. The most common sites of disease recurrencewere brain, lung and liver.Conclusions. Patients with TNBC who have a pCR in the breast and axillarynodes have a significantly improved disease-free and overall survival ratecompared with patients with residual disease after neoadjuvantchemotherapy