Neoadjuvant, anthracycline-free chemotherapy with carboplatin and docetaxel in triple-negative, early-stage breast cancer: a multicentric analysis of rates of pathologic complete response and survival

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).

Precision Breast Cancer Medicine: Early Stage Triple Negative Breast Cancer-A Review of Molecular Characterisation, Therapeutic Targets and Future Trends

Personalised approaches to the management of all solid tumours are increasing rapidly, along with wider accessibility for clinicians. Advances in tumour characterisation and targeted therapies have placed triple-negative breast cancers (TNBC) at the forefront of this approach. TNBC is a highly heterogeneous disease with various histopathological features and is driven by distinct molecular alterations. The ability to tailor individualised and effective treatments for each patient is of particular importance in this group due to the high risk of distant recurrence and death. The mainstay of treatment across all subtypes of TNBC has historically been cytotoxic chemotherapy, which is often associated with off-target tissue toxicity and drug resistance. Neoadjuvant chemotherapy is commonly used as it allows close monitoring of early treatment response and provides valuable prognostic information. Patients who achieve a complete pathological response after neoadjuvant chemotherapy are known to have significantly improved long-term outcomes. Conversely, poor responders face a higher risk of relapse and death. The identification of those subgroups that are more likely to benefit from breakthroughs in the personalised approach is a challenge of the current era where several targeted therapies are available. This review presents an overview of contemporary practice, and promising future trends in the management of early TNBC. Platinum chemotherapy, DNA damage response (DDR) inhibitors, immune checkpoint inhibitors, inhibitors of the PI3K-AKT-mTOR, and androgen receptor (AR) pathways are some of the increasingly studied therapies which will be reviewed. We will also discuss the growing evidence for less-developed agents and predictive biomarkers that are likely to contribute to the forthcoming advances in this field. Finally, we will propose a framework for the personalised management of TNBC based upon the integration of clinico-pathological and molecular features to ensure that long-term outcomes are optimised.

Pathological complete response following cisplatin or carboplatin-based neoadjuvant chemotherapy for triple-negative breast cancer: A systematic review and meta-analysis

The addition of platinum compounds to standard neoadjuvant chemotherapy (NACT) for triple-negative breast cancer (TNBC) is highly controversial. Platinum agents, such as cisplatin and carboplatin, are DNA-damaging agents which exhibit activity in breast cancer, particularly in the TNBC subgroup. In order to assess the efficacy of each most representative platinum agent (cisplatin and carboplatin) in patients with TNBC treated with NACT, the present study performed a systematic review and meta-analysis of all available published studies on TNBC. A search of PubMed was performed to identify studies that investigated platinum-based NACT in patients with TNBC. The primary endpoints were the pooled rate of the pathological complete response (pCR) between cisplatin vs. carboplatin-based NACT. A total of 24 studies were selected (17 studies for carboplatin and 6 studies for cisplatin and 1 study with both carboplatin and cisplatin, with 20 prospective studies) for the analysis of 1,711 patients with TNBC. Overall, the pooled rate of pCR in patients treated with platinum-based NACT was 48%. No significant differences were observed between the rates of pCR obtained under carboplatin vs cisplatin treatment. The carboplatin pCR rate was 0.470 [95% confidence interval (CI), 0.401-0.539], while the cisplatin pCR rate was 0.473 (95% CI, 0.379-0.568). The comparison between these two categories revealed no significant differences (P=0.959). In the whole, the present study demonstrates that neoadjuvant platinum-based chemotherapy improves the pCR rate in patients with TNBC, regardless of the platinum agent used. Carboplatin may thus represent a viable option due to its more favorable toxicity profile.

Immunogenomic profiling and pathological response results from a clinical trial of docetaxel and carboplatin in triple-negative breast cancer

PURPOSE

Patients with triple-negative breast cancer (TNBC) who do not achieve pathological complete response (pCR) following neoadjuvant chemotherapy have a high risk of recurrence and death. Molecular characterization may identify patients unlikely to achieve pCR. This neoadjuvant trial was conducted to determine the pCR rate with docetaxel and carboplatin and to identify molecular alterations and/or immune gene signatures predicting pCR.

EXPERIMENTAL DESIGN

Patients with clinical stages II/III TNBC received 6 cycles of docetaxel and carboplatin. The primary objective was to determine if neoadjuvant docetaxel and carboplatin would increase the pCR rate in TNBC compared to historical expectations. We performed whole-exome sequencing (WES) and immune profiling on pre-treatment tumor samples to identify alterations that may predict pCR. Thirteen matching on-treatment samples were also analyzed to assess changes in molecular profiles.

RESULTS

Fifty-eight of 127 (45.7%) patients achieved pCR. There was a non-significant trend toward higher mutation burden for patients with residual cancer burden (RCB) 0/I versus RCB II/III (median 80 versus 68 variants, p 0.88). TP53 was the most frequently mutated gene, observed in 85.7% of tumors. EGFR, RB1, RAD51AP2, SDK2, L1CAM, KPRP, PCDHA1, CACNA1S, CFAP58, COL22A1, and COL4A5 mutations were observed almost exclusively in pre-treatment samples from patients who achieved pCR. Seven mutations in PCDHA1 were observed in pre-treatment samples from patients who did not achieve pCR. Several immune gene signatures including IDO1, PD-L1, interferon gamma signaling, CTLA4, cytotoxicity, tumor inflammation signature, inflammatory chemokines, cytotoxic cells, lymphoid, PD-L2, exhausted CD8, Tregs, and immunoproteasome were upregulated in pre-treatment samples from patients who achieved pCR.

CONCLUSION

Neoadjuvant docetaxel and carboplatin resulted in a pCR of 45.7%. WES and immune profiling differentiated patients with and without pCR.

TRIAL REGISTRATION

Clinical trial information: NCT02124902, Registered 24 April 2014 & NCT02547987, Registered 10 September 2015.

Neoadjuvant Immune-Checkpoint Blockade in Triple-Negative Breast Cancer: Current Evidence and Literature-Based Meta-Analysis of Randomized Trials

Simple Summary

Breast cancer is a heterogeneous disease, which encompasses several subgroups of entities widely varying by clinical-pathological features. Triple negative breast cancer is characterized by a particularly aggressive biological behavior. The administration of chemotherapy has long represented the most efficacious weapon in combating triple negative breast cancer in both its initial and late phase of development. A pivot point has been recently reached throughout the approval of the immunotherapic agent atezolizumab in combination with chemotherapy as first-line treatment for programmed-death ligand 1-positive, unresectable locally advanced, or metastatic triple-negative breast cancer. Results from the registrative trial, IMpassion 130, have increasingly fueled the flourishing of studies of immune-checkpoint inhibitors in the early stage of triple negative breast cancer development. We critically interpret results from the most recent literature in light of relevant issues of methodological nature and also present a quantitative summary of data from the inherent trials. Future directions are also highlighted.

Abstract

Chemotherapy based on the sequential use of anthracyclines and taxanes has long represented the most efficacious approach in the management of early-stage, triple-negative breast cancer, whose aggressive behavior is widely renowned. This standard chemotherapy backbone was subsequently enriched by the use of carboplatin, based on its association with increased pathologic complete response and efficacy in the metastatic setting. Following the results from the IMpassion130 trial, the recent approval of the immunotherapic agent atezolizumab in combination with chemotherapy as first-line treatment for programmed-death ligand 1-positive, unresectable locally advanced, or metastatic triple-negative breast cancer increasingly fueled the flourishing of trials of immune-checkpoint inhibitors in the early setting. In this work, we review the most recent inherent literature in light of key methodological issues and provide a quantitative summary of the results from phase II–III randomized trials of immunotherapic agents combined with chemotherapy in the setting of interest. Hints regarding future directions are also discussed.

Lymph node ratio as best prognostic factor in triple-negative breast cancer patients with residual disease after neoadjuvant chemotherapy

Although lymph node status (ypN) is one of the most important prognostic factors of survival, the lymph node ratio (LNR) has emerged as an equitable factor. We aimed to compare the prognostic value of both ypN and LNR in patients with residual triple-negative breast cancer (TNBC) after neo-adjuvant chemotherapy (NAC). This was a retrospective cohort study of patients treated in a tertiary care center during the period 2000-2014. We stratified the population based on LNR (≤0.20, 0.20-0.65, and >0.65) and ypN (N1, N2, and N3) status. The overall survival (OS) and progression-free survival (PFS) were estimated with Kaplan-Meier curves and the log-rank + test. We further compared patient mortality and disease recurrence using multivariate Cox regression analysis. We evaluated 169 patients with a median follow-up of 87 months. At 2 years of follow-up, patients with low-risk LNR compared to those with moderate and high risk had a higher PFS (54% vs 31% vs 18%, respectively; P < .001) and OS (74% vs 64% vs 45%, respectively; P < .001). Moreover, ypN1 patients compared to ypN2 and ypN3 showed similar results in PFS (53% vs 35% vs 19%, respectively; P = .001) and OS (73% vs 69% vs 43%, respectively; P < .001). Compared to the low-risk population, patients with moderate (hazard ratio [HR]: 3.50; 95% confidence interval [CI]: 1.41-8.71) and high risk (HR: 6.90; 95% CI: 2.29-20.77) had a worse PFS. Regarding OS, moderate-risk (HR: 2.85; 95% CI: 1.10-7.38) and high-risk patients (HR: 6.48; 95% CI: 2.13-19.76) showed considerably worse outcomes. On the other hand, ypN staging was not associated with PFS or OS in the multivariate analysis. The LNR is a better prognostic factor of survival than ypN. The LNR should be considered in the stratification of risk after NAC in patients with TNBC.

Survival analysis of carboplatin added to an anthracycline/taxane-based neoadjuvant chemotherapy and HRD score as predictor of response-final results from GeparSixto

Background

In the neoadjuvant GeparSixto study, adding carboplatin to taxane- and anthracycline-based chemotherapy improved pathological complete response (pCR) rates in patients with triple-negative breast cancer (TNBC). Here, we present survival data and the potential prognostic and predictive role of homologous recombination deficiency (HRD).

Patients and methods

Patients were randomized to paclitaxel plus nonpegylated liposomal doxorubicin (Myocet®) (PM) or PM plus carboplatin (PMCb). The secondary study end points disease-free survival (DFS) and overall survival (OS) were analyzed. Median follow-up was 47.3 months. HRD was among the exploratory analyses in GeparSixto and was successfully measured in formalin-fixed, paraffin-embedded tumor samples of 193/315 (61.3%) participants with TNBC. Homologous recombination (HR) deficiency was defined as HRD score ≥42 and/or presence of tumor BRCA mutations (tmBRCA).

Results

A significantly better DFS (hazard ratio 0.56, 95% CI 0.34-0.93; P = 0.022) was observed in patients with TNBC when treated with PMCb. The improvement of OS with PMCb was not statistically significant. Additional carboplatin did not improve DFS or OS in patients with HER2-positive tumors. HR deficiency was detected in 136 (70.5%) of 193 triple-negative tumors, of which 82 (60.3%) showed high HRD score without tmBRCA. HR deficiency independently predicted pCR (ypT0 ypN0) [odds ratio (OR) 2.60, 95% CI 1.26-5.37, P = 0.008]. Adding carboplatin to PM significantly increased the pCR rate from 33.9% to 63.5% in HR deficient tumors (P = 0.001), but only marginally in HR nondeficient tumors (from 20.0% to 29.6%, P = 0.540; test for interaction P = 0.327). pCR rates with carboplatin were also higher (63.2%) than without carboplatin (31.7%; OR 3.69, 1.46-9.37, P = 0.005) in patients with high HRD score but no tmBRCA. DFS rates were improved with addition of carboplatin, both in HR nondeficient (hazard ratio 0.44, 0.17-1.17, P = 0.086) and HR deficient tumors (hazard ratio 0.49, 0.23-1.04, P = 0.059).

Conclusions

The addition of carboplatin to neoadjuvant PM improved DFS significantly in TNBC. Long-term survival analyses support the neoadjuvant use of carboplatin in TNBC. HR deficiency in TNBC and HRD score in non-tmBRCA TNBC are predictors of response. HRD does not predict for carboplatin benefit.

Dexmedetomidine alleviates doxorubicin cardiotoxicity by inhibiting mitochondrial reactive oxygen species generation

Cardiotoxicity largely limits the application of doxorubicin (Dox) for cancer treatment. Dexmedetomidine (Dex), a selective agonist of α2-adrenergic receptor, has been suggested to exert cardioprotection against myocardial injury. However, the effect and underlying mechanisms of Dex on Dox cardiotoxicity remain unknown. In this study, C57BL/6 mice were treated with Dox followed by Dex administration. Cardiomyocytes were co-incubated with Dox and Dex in vitro. The results showed that Dex markedly attenuated cardiac dysfunction induced by Dox. TUNEL staining exhibited that Dex inhibited Dox-induced cardiomyocyte apoptosis in myocardium. Moreover, the expression of anti-apoptotic protein Bcl-2 was increased, whereas the expression of pro-apoptotic protein Bax was decreased by Dex. Dox-induced the increase of reactive oxygen species (ROS), superoxide anion, and mitochondrial ROS (mROS) generation in myocardial tissues were significantly inhibited after Dex administration. In in vitro study, it was further confirmed that Dex prevented Dox-induced cardiomyocyte apoptosis and injury. However, the stimulation of mROS generation reversed the effect of Dex in cardiomyocytes. Mechanically, Dex blocked Dox-induced the ubiquitination of peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α), leading to the restoration of PGC-1α and downstream oxidative stress-protective molecules uncoupling protein 2 and manganese-dependent superoxide dismutase expression. Taken together, this study demonstrates that Dex exerts cardioprotection against Dox cardiotoxicity by attenuating mitochondrial dysfunction, oxidative stress, and cardiomyocyte apoptosis via inhibiting PGC-1α-signaling pathway inactivation. This suggests that Dex may be a potential therapeutic strategy for Dox cardiotoxicity treatment.

Identification of transcription factor-miRNA-lncRNA feed-forward loops in breast cancer subtypes

Previous studies have demonstrated that transcription factor-miRNA-gene feed-forward loops (FFLs) played important roles in tumorigenesis. However, the lncRNA-involved FFLs have not been explored very well. Understanding the characteristics of lncRNA-involved FFLs in breast cancer subtypes may be a key question with clinical implications. In this study, we firstly constructed an integrated background regulatory network. Then, based on mRNA, miRNA, and lncRNA differential expression, we identified 147, 140, 284, 1031 dysregulated FFLs for luminal A, luminal B, HER2+ and basal-like subtype of breast cancer, respectively. Importantly, the known breast cancer-associated lncRNAs and miRNAs were enriched in the identified dysregulated FFLs. Through merging the dysregulated FFLs, we constructed the regulatory sub-network for each subtype. We found that all sub-networks were enriched in the well-known cancer-related pathways, such as cell cycle, pathways in cancer. Next, we also identified potential prognostic FFLs for subtypes of breast cancer, such as the hsa-miR-182-5p_JUN_XIST in basal-like subtype. Finally, we also discussed the potential application of inferring the candidate drugs for breast cancer treatment through modulating the lncRNA expression in the dysregulated FFLs. Collectively, this study elucidated the roles of lncRNA-involved FFLs in breast cancer subtypes, which could contribute to understanding breast cancer pathogenesis and improving the treatment.

Beta-hydroxybutyrate (3-OHB) can influence the energetic phenotype of breast cancer cells, but does not impact their proliferation and the response to chemotherapy or radiation

Background

Ketogenic diets (KDs) or short-term fasting are popular trends amongst supportive approaches for cancer patients. Beta-hydroxybutyrate (3-OHB) is the main physiological ketone body, whose concentration can reach plasma levels of 2–6 mM during KDs or fasting. The impact of 3-OHB on the biology of tumor cells described so far is contradictory. Therefore, we investigated the effect of a physiological concentration of 3 mM 3-OHB on metabolism, proliferation, and viability of breast cancer (BC) cells in vitro.

Methods

Seven different human BC cell lines (BT20, BT474, HBL100, MCF-7, MDA-MB 231, MDA-MB 468, and T47D) were cultured in medium with 5 mM glucose in the presence of 3 mM 3-OHB at mild hypoxia (5% oxygen) or normoxia (21% oxygen). Metabolic profiling was performed by quantification of the turnover of glucose, lactate, and 3-OHB and by Seahorse metabolic flux analysis. Expression of key enzymes of ketolysis as well as the main monocarboxylic acid transporter MCT2 and the glucose-transporter GLUT1 was analyzed by RT-qPCR and Western blotting. The effect of 3-OHB on short- and long-term cell proliferation as well as chemo- and radiosensitivity were also analyzed.

Results

3-OHB significantly changed the oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) in BT20 cells resulting in a more oxidative energetic phenotype. MCF-7 and MDA-MB 468 cells had increased ECAR only in response to 3-OHB, while the other three cell types remained uninfluenced. All cells expressed MCT2 and GLUT1, thus being able to uptake the metabolites. The consumption of 3-OHB was not strongly linked to mRNA overexpression of key enzymes of ketolysis and did not correlate with lactate production and glucose consumption. Neither 3-OHB nor acetoacetate did interfere with proliferation. Further, 3-OHB incubation did not modify the response of the tested BC cell lines to chemotherapy or radiation.

Conclusions

We found that a physiological level of 3-OHB can change the energetic profile of some BC cell lines. However, 3-OHB failed to influence different biologic processes in these cells, e.g., cell proliferation and the response to common breast cancer chemotherapy and radiotherapy. Thus, we have no evidence that 3-OHB generally influences the biology of breast cancer cells in vitro.

Electronic supplementary material

The online version of this article (10.1186/s40170-018-0180-9) contains supplementary material, which is available to authorized users.

Pathological Response in a Triple-Negative Breast Cancer Cohort Treated with Neoadjuvant Carboplatin and Docetaxel According to Lehmann's Refined Classification

Purpose: Triple-negative breast cancer (TNBC) requires the iden- tification of reliable predictors of response to neoadjuvant chemotherapy (NACT). For this purpose, we aimed to evaluate the performance of the TNBCtype-4 classifier in a cohort of patients with TNBC treated with neoadjuvant carboplatin and docetaxel (TCb).Methods: Patients with TNBC were accrued in a nonrandomized trial of neoadjuvant carboplatin AUC 6 and docetaxel 75 mg/m² for six cycles. Response was evaluated in terms of pathologic complete response (pCR, ypT0/is ypN0) and residual cancer burden by Symmans and colleagues. Lehmann's subtyping was performed using the TNBCtype online tool from RNAseq data, and germline sequencing of a panel of seven DNA damage repair genes was conducted.Results: Ninety-four out of the 121 patients enrolled in the trial had RNAseq available. The overall pCR rate was 44.7%. Lehmann subtype distribution was 34.0% BL1, 20.2% BL2, 23.4% M, 14.9% LAR, and 7.4% were classified as ER+. Response to NACT with TCb was significantly associated with Lehmann subtype (P = 0.027), even in multivariate analysis including tumor size and nodal involvement, with BL1 patients achieving the highest pCR rate (65.6%), followed by BL2 (47.4%), M (36.4%), and LAR (21.4%). BL1 was associated with a significant younger age at diagnosis and higher ki67 values. Among our 10 germline mutation carriers, 30% were BL1, 40% were BL2, and 30% were M.Conclusions: TNBCtype-4 is associated with significantly different pCR rates for the different subtypes, with BL1 and LAR displaying the best and worse responses to NACT, respectively. Clin Cancer Res; 24(8); 1845-52. ©2018 AACR.

Association of T-cadherin levels with the response to neoadjuvant chemotherapy in locally advanced breast cancer

Purpose

To examine the association of T-cadherin with pathologic complete response (pCR) after neoadjuvant chemotherapy for locally advanced breast cancer.

Results

T-cadherin expression before and after neoadjuvant chemotherapy was similar (P = 0.162). The multivariable analysis indicated that negative T-cadherin expression was independently associated with pCR after neoadjuvant TAC chemotherapy (P = 0.001).

Materials and Methods

A total of 136 patients with locally advanced breast cancer received four cycles of neoadjuvant TAC chemotherapy (docetaxel + epirubicin + cyclophosphamide), followed by surgery. T-cadherin, estrogen receptor (ER), progesterone receptor (PR), HER-2, and Ki-67 were analyzed by immunohistochemistry. The association between T-cadherin expression and pCR after neoadjuvant chemotherapy was analyzed using multivariable logistic analysis.

Conclusions

Negative T-cadherin expression before and after neoadjuvant chemotherapy for locally advanced breast cancer was similar. T-cadherin could be considered an independent factor associated with the efficacy of such therapy.