Characterization of circulating tumor cells in early breast cancer patients receiving neoadjuvant chemotherapy

Background and Aims:

The aim of this study was to characterize circulating tumor cells (CTCs) during neoadjuvant chemotherapy (NACT) in early and locally advanced breast cancer (LABC) patients. Using ultrasound, tumor volume measurement was compared with the presence and the molecular nature of CTCs over multiple time intervals corresponding to treatment periods.

Methods:

A total of 20 patients diagnosed with breast cancer (BC) of different histotypes were monitored during the NACT period and in the follow-up period (~5 years). Peripheral blood for CTCs (n = 115) was taken prior to NACT, after two to three chemotherapy cycles, after the completion of NACT (before surgery) and at some time points during adjuvant therapy. CTCs were enriched using a size-based filtration method (MetaCell®) capturing viable cells, which enabled vital fluorescence microscopy. A set of tumor-associated (TA) genes and chemoresistance-associated (CA) genes was analyzed by qPCR in the enriched CTC fractions.

Results:

The analysis of tumor volume reduction after administration of anthracyclines (AC) and taxanes (TAX) during NACT showed that AC therapy was responsive in 60% (12/20) of tumors, whereas TAX therapy was responsive in 30% (6/20; n.s.). After NACT, CTCs were still present in 70.5% (12/17) of patients (responders versus non-responders, 61.5% versus 100%; not significant).

In triple-negative BC (TNBC) patients (n = 8), tumor volume reduction was observed in 75% cases. CTCs were significantly reduced in 42.9% of all HER2-negative BC patients. In HER2+ tumors, CTC reduction was reported in 16.6% only. Relapses were also more prevalent in the HER2-positive patient group (28.5 versus 66.6%).

During NACT, the presence of CTCs (three tests for each patient) identified patients with relapses and indicated significantly shorter progression-free survival (PFS) rates (p = 0.03). Differentiation between progressive disease and non-progressive disease was obtained when the occurrence of excessive expression for CA genes in CTCs was compared (p = 0.024). Absence of tumor volume reduction was also significantly indicative for progressive disease (p = 0.0224).

Disseminated CTCs in HER2-negative tumors expressed HER2 in 29% of samples collected during the overall follow-up period (16/55), and in 32% of samples during the follow-up of NACT (10/31). The change accounted for 78.5% of HER2-negative patients (11/14) in total, and 63.6% of the conversion cases occurred during NACT (7/11). For the remaining four patients (36.3%), conversion to HER2+ CTCs occurred later during adjuvant therapy. We believe there is the possibility of preventing further progression by identifying less responsive tumors during NACT using CTC monitoring, which could also be used effectively during adjuvant therapy.

Efficacy and safety of neoadjuvant immune checkpoint inhibitors in early-stage triple-negative breast cancer: a systematic review and meta-analysis

PURPOSE

There is uncertainty regarding the role of adding immune checkpoint inhibitors (ICIs) to neoadjuvant chemotherapy (NACT) in early-stage triple-negative breast cancer (TNBC).

METHODS

We identified randomized controlled trials (RCTs) comparing ICIs combined with NACT to NACT in early-stage TNBC. Efficacy outcomes included pathological complete response (pCR) and event-free survival (EFS). Toxicity data included any grade 3/4 adverse events (AEs), serious AEs, AEs leading to death, common and meaningful AEs associated with chemotherapy and immune-related AEs. Odds ratio (ORs), hazard ratios (HR) and their respective 95% confidence intervals (CI) for efficacy and toxicity were extracted and pooled in a meta-analysis. Differences in the odds for pCR between programmed death ligand 1 (PD-L1) status and between PD-L1 and PD-1 inhibitors were also assessed.

RESULTS

Five RCTs comprising 2,075 patients were analyzed. Compared to NACT alone, combination of ICIs and NACT significantly improved pCR (OR 1.75, 95% CI 1.25-2.47, p = 0.001) and EFS (HR 0.66, 95% CI 0.48-0.91, p = 0.01). Magnitude of effect on pCR was similar between PD-L1-positive and PD-L1-negative tumors (p for the subgroup difference = 0.80) and between PD-L1 and PD-1 inhibitors (p = 0.27). The combination treatment resulted in higher odds of any grade 3/4 AEs (OR 1.31, p = 0.02) and serious AEs (OR 1.84, p = 0.006), with no statistically significant difference in AEs leading to death (OR 1.67, p = 0.51). Higher magnitude of toxicity was observed for immune-related AEs.

CONCLUSION

Combination of ICIs and NACT were associated with improved outcome in early-stage TNBC while increasing toxicity significantly. Longer follow-up is desired to better understand the risk and benefit ratio of this combination.

Vessel co-option in cancer

All solid tumours require a vascular supply in order to progress. Although the ability to induce angiogenesis (new blood vessel growth) has long been regarded as essential to this purpose, thus far, anti-angiogenic therapies have shown only modest efficacy in patients. Importantly, overshadowed by the literature on tumour angiogenesis is a long-standing, but continually emerging, body of research indicating that tumours can grow instead by hijacking pre-existing blood vessels of the surrounding nonmalignant tissue. This process, termed vessel co-option, is a frequently overlooked mechanism of tumour vascularization that can influence disease progression, metastasis and response to treatment. In this Review, we describe the evidence that tumours located at numerous anatomical sites can exploit vessel co-option. We also discuss the proposed molecular mechanisms involved and the multifaceted implications of vessel co-option for patient outcomes.

Pilot study of bevacizumab in combination with docetaxel and cyclophosphamide as adjuvant treatment for patients with early stage HER-2 negative breast cancer, including analysis of candidate circulating markers of cardiac toxicity: ICORG 08-10 trial

Background:

Combining bevacizumab and chemotherapy produced superior response rates compared with chemotherapy alone in metastatic breast cancer. As bevacizumab may cause hypertension (HTN) and increase the risk of cardiac failure, we performed a pilot study to evaluate the feasibility and toxicity of a non-anthracycline-containing combination of docetaxel with cyclophosphamide and bevacizumab in early stage breast cancer patients.

Methods:

Treatment consisted of four 3-weekly cycles of docetaxel and cyclophosphamide (75/600 mg/m²). Bevacizumab was administered 15 mg/kg intravenously on day 1, and then every 3 weeks to a total of 18 cycles of treatment. Serum biomarker concentrations of vascular endothelial growth factor (VEGF), cardiac troponin-I (cTnI), myeloperoxidase (MPO), and placental growth factor (PlGF) were quantified using enzyme-linked immunosorbent assay (ELISA) in 62 patients at baseline and whilst on treatment to determine their utility as biomarkers of cardiotoxicity, indicated by left ventricular ejection fraction (LVEF).

Results:

A total of 106 patients were accrued in nine sites. Median follow up was 65 months (1–72 months). Seventeen protocol-defined relapse events were observed, accounting for an overall disease-free survival (DFS) rate of 84%. The DFS rates for hormone receptor positive (HR+) and triple-negative (TN) patients were 95% versus 43%, respectively. The median time to relapse was 25 (12–54) months in TN patients versus 38 (22–71) months in HR+ patients. There have been 13 deaths related to breast cancer . The overall survival (OS) rate was 88%. The 5-year OS rate in HR+ versus TN was 95% versus 57%. None of the measured biomarkers predicted the development of cardiotoxicity.

Conclusions:

We observed a low relapse rate in node-positive, HR+ patients; however, results in TN breast cancer were less encouraging. Given the negative results of three large phase III trials, it is unlikely that this approach will be investigated further.

Trial Registration

ClinicalTrials.gov Identifier: NCT00911716.

ROR1 Potentiates FGFR Signaling in Basal-Like Breast Cancer

Among all breast cancer types, basal-like breast cancer (BLBC) represents an aggressive subtype that lacks targeted therapy. We and others have found that receptor tyrosine kinase-like orphan receptor 1 (ROR1) is overexpressed in BLBC and other types of cancer and that ROR1 is significantly correlated with patient prognosis. In addition, using primary patient-derived xenografts (PDXs) and ROR1-knockout BLBC cells, we found that ROR1⁺ cells form tumors in immunodeficient mice. We developed an anti-ROR1 immunotoxin and found that targeting ROR1 significantly kills ROR1⁺ cancer cells and slows down tumor growth in ROR1⁺ xenografts. Our bioinformatics analysis revealed that ROR1 expression is commonly associated with the activation of FGFR-mediated signaling pathway. Further biochemical analysis confirmed that ROR1 stabilized FGFR expression at the posttranslational level by preventing its degradation. CRISPR/Cas9-mediated ROR1 knockout significantly reduced cancer cell invasion at cellular levels by lowering FGFR protein and consequent inactivation of AKT. Our results identified a novel signaling regulation from ROR1 to FGFR and further confirm that ROR1 is a potential therapeutic target for ROR1⁺ BLBC cells.

Bevacizumab in the neoadjuvant treatment of human epidermal growth factor receptor 2-negative breast cancer: A meta-analysis of randomized controlled trials

Several randomized clinical trials have suggested the effectiveness of bevacizumab (Bev) in early and advanced breast cancer; however, due to the increased toxicity and lack of a clear long-term survival benefit, there is currently no defined role for Bev in breast cancer in the USA, while it has been approved in Europe. We herein sought to conduct a meta-analysis of large randomized trials comparing the efficacy and long-term outcome of neoadjuvant chemotherapy with Bev compared with chemotherapy without Bev in human epidermal factor receptor 2 (HER2)-negative breast cancer. A search was conducted through PubMed and Ovid Medline databases. Among the 279 articles identified, 5 met the eligibility criteria and were included in the present analysis. A total of 2,268 patients treated with Bev and 2,278 treated without Bev were analyzed. Pathological complete response (pCR) was obtained in 35% of patients treated with Bev and in 26% of those treated without Bev. A statistically significant increase (26%) in the incidence of pCR was observed in the Bev-treated group. However, patients treated with Bev exhibited no significant difference in the risk of disease recurrence or death. To the best of our knowledge, this is the first meta-analysis addressing the long-term outcomes of Bev in combination with chemotherapy in the neoadjuvant treatment of HER2-negative breast cancer. The results confirmed the significant benefit of Bev combined with chemotherapy compared with chemotherapy alone on breast cancer response, in both triple-negative and hormone receptor-positive cases. However, this benefit does not translate into a long-term disease-free or definitive overall survival advantage. Optimizing patient selection is desirable for maximizing the long-term benefits of Bev, while reducing cost and treatment-related adverse effects. Future efforts directed toward the discovery of predictive markers would be crucial for identifying the subset(s) of breast cancer patients who are most likely to benefit from Bev therapy.

Pre- and post-operative anti-PD-L1 plus anti-angiogenic therapies in mouse breast or renal cancer models of micro- or macro-metastatic disease

BACKGROUND

There are phase 3 clinical trials underway evaluating anti-PD-L1 antibodies as adjuvant (postoperative) monotherapies for resectable renal cell carcinoma (RCC) and triple-negative breast cancer (TNBC); in combination with antiangiogenic VEGF/VEGFR2 inhibitors (e.g., bevacizumab and sunitinib) for metastatic RCC; and in combination with chemotherapeutics as neoadjuvant (preoperative) therapies for resectable TNBC.

METHODS

This study investigated these and similar clinically relevant drug combinations in highly translational preclinical models of micro- and macro-metastatic disease that spontaneously develop after surgical resection of primary kidney or breast tumours derived from orthotopic implantation of murine cancer cell lines (RENCA^luc or EMT-6/CDDP, respectively).

RESULTS

In the RENCA^luc model, adjuvant sunitinib plus anti-PD-L1 improved overall survival compared to either drug alone, while the same combination was ineffective as early therapy for unresected primary tumours or late-stage therapy for advanced metastatic disease. In the EMT-6/CDDP model, anti-PD-L1 was highly effective as an adjuvant monotherapy, while its combination with paclitaxel chemotherapy (with or without anti-VEGF) was most effective as a neoadjuvant therapy.

CONCLUSIONS

Our preclinical data suggest that anti-PD-L1 plus sunitinib may warrant further investigation as an adjuvant therapy for RCC, while anti-PD-L1 may be improved by combining with chemotherapy in the neoadjuvant but not the adjuvant setting of treating breast cancer.

The Effect of Perioperative Bevacizumab on Disease-Free and Overall Survival in Locally Advanced HER-2 Negative Breast Cancer: A Meta-Analysis

Introduction

Multiple trials demonstrated that adding Bevacizumab to the standard neoadjuvant chemotherapy in HER-2 negative breast cancer increases pathological complete response. We conducted this meta-analysis to evaluate that effect on survival.

Methods

We performed a systematic search for randomized trials measuring the effect of adding either neoadjuvant or adjuvant Bevacizumab to the standard chemotherapy on disease-free and overall survival in breast cancer surgical candidates. The Mantel-Haenszel method and random effect model were used to analyze the data. A total of 7 randomized controlled trials were included in the analysis with a mean follow-up of 45 months.

Results

No statistically significant difference in overall survival was found after adding Bevacizumab to the standard chemotherapy in the overall study population, HR=0.9, 95% CI (90.72-1.13), estrogen/ progesterone positive subgroup, HR=0.99, 95% CI (0.72-1.35), or in triple negative breast cancer, HR=0.88, 95% CI (0.77-1.01). However, there was a small but significant improvement in disease-free survival in triple negative breast cancer with a HR of 0.88, 95% CI (0.78-0.98), but not in estrogen/ progesterone receptor positive tumors, HR=1.01, 95% CI (0.81-1.26).

Conclusions

The addition of Bevacizumab along with the standard chemotherapy would not improve overall survival in breast cancer surgical candidates, however, due to a small but significant improvement on disease-free survival in triple negative breast cancer, that would not eliminate the possibility of a certain subgroup of the latter who might benefit from adding Bevacizumab.

Disease-free and overall survival at 3.5 years for neoadjuvant bevacizumab added to docetaxel followed by fluorouracil, epirubicin and cyclophosphamide, for women with HER2 negative early breast cancer: ARTemis Trial

Background

The ARTemis trial previously reported that addition of neoadjuvant bevacizumab (Bev) to docetaxel (D) followed by fluorouracil, epirubicin and cyclophosphamide (D-FEC) in HER2 negative breast cancer improved the pathological complete response (pCR) rate. We present disease-free survival (DFS) and overall survival (OS) with central pathology review.

Patients and methods

Patients were randomized to 3 cycles of D followed by 3 cycles of FEC (D-FEC), ±4 cycles of Bev (Bev + D-FEC). DFS and OS were analyzed by treatment and by central pathology reviewed pCR and Residual Cancer Burden (RCB) class.

Results

A total of 800 patients were randomized [median follow-up 3.5 years (IQR 3.2–4.4)]. DFS and OS were similar across treatment arms [DFS hazard ratio (HR)=1.18 (95% CI 0.89–1.57), P = 0.25; OS HR = 1.26 (95% CI 0.90–1.76), P = 0.19). Both local pathology report review and central histopathology review confirmed a significant improvement in DFS and OS for patients who achieved a pCR [DFS HR = 0.38 (95% CI 0.23–0.63), P < 0.001; OS HR = 0.43 (95% CI 0.24–0.75), P = 0.003]. However, significant heterogeneity was observed (P = 0.02); larger improvements in DFS were obtained with a pCR achieved with D-FEC than a pCR achieved with Bev + D-FEC. As RCB class increased, significantly worse DFS and OS was observed (P for trend <0.0001), which effect was most marked in the ER negative group.

Conclusions

The addition of short course neoadjuvant Bev to standard chemotherapy did not demonstrate a DFS or OS benefit. Achieving a pCR with D-FEC is associated with improved DFS and OS but not when pCR is achieved with Bev + D-FEC. At the present time therefore, Bev is not recommended in early breast cancer.

ClinicalTrials.gov number

NCT01093235.

Update on the Treatment of Early-Stage Triple-Negative Breast Cancer

OPINION STATEMENT

Triple-negative breast cancer (TNBC) accounts for 15% of all breast cancers and is associated with poor long-term outcomes compared to other breast cancer subtypes. Currently, chemotherapy remains the main modality of treatment for early-stage TNBC, as there is no approved targeted therapy for this subtype. The biologic heterogeneity of TNBC has hindered the development and evaluation of novel agents, but recent advancements in subclassifying TNBC have paved the way for further investigation of more effective systemic therapies, including cytotoxic and targeted agents. TNBC is enriched for germline BRCA mutation and for somatic deficiencies in homologous recombination DNA repair, the so-called "BRCAness" phenotype. Together, germline BRCA mutations and BRCAness are promising biomarkers of susceptibility to DNA-damaging therapy. Various investigational approaches are consequently being investigated in early-stage TNBC, including immune checkpoint inhibitors, platinum compounds, PI3K pathway inhibitors, and androgen receptor inhibitors. Due to the biological diversity found within TNBC, patient selection based on molecular biomarkers could aid the design of early-phase clinical trials, ultimately accelerating the clinical application of effective new agents. TNBC is an aggressive breast cancer subtype, for which multiple targeted approaches will likely be required for patient outcomes to be substantially improved.

Genome-Wide Association Study for Anthracycline-Induced Congestive Heart Failure

PURPOSE

Anthracycline-induced congestive heart failure (CHF) is a rare but serious toxicity associated with this commonly employed anticancer therapy. The ability to predict which patients might be at increased risk prior to exposure would be valuable to optimally counsel risk-to-benefit ratio for each patient. Herein, we present a genome-wide approach for biomarker discovery with two validation cohorts to predict CHF from adult patients planning to receive anthracycline.

EXPERIMENTAL DESIGN

We performed a genome-wide association study in 3,431 patients from the randomized phase III adjuvant breast cancer trial E5103 to identify single nucleotide polymorphism (SNP) genotypes associated with an increased risk of anthracycline-induced CHF. We further attempted candidate validation in two independent phase III adjuvant trials, E1199 and BEATRICE.

RESULTS

When evaluating for cardiologist-adjudicated CHF, 11 SNPs had a P value <10^-5, of which nine independent chromosomal regions were associated with increased risk. Validation of the top two SNPs in E1199 revealed one SNP rs28714259 that demonstrated a borderline increased CHF risk (P = 0.04, OR = 1.9). rs28714259 was subsequently tested in BEATRICE and was significantly associated with a decreased left ventricular ejection fraction (P = 0.018, OR = 4.2).

CONCLUSIONS

rs28714259 represents a validated SNP that is associated with anthracycline-induced CHF in three independent, phase III adjuvant breast cancer clinical trials. Clin Cancer Res; 23(1); 43-51. ©2016 AACR.

The Effect on Surgical Complications of Bevacizumab Added to Neoadjuvant Chemotherapy for Breast Cancer: NRG Oncology/NSABP Protocol B-40

BACKGROUND

NRG Oncology/NSABP trial B-40 tested the impact of adding bevacizumab (bev) to neoadjuvant chemotherapy for operable breast cancer. Secondary endpoints included rates of surgical complications after surgery in patients who did or did not receive bev.

METHODS

A total of 1206 women with HER2-negative operable breast cancer were randomly assigned to receive one of three different docetaxel-plus-anthracycline-based regimens, without or with bev (15 mg/kg every 3 weeks) for the first 6 of 8 cycles and for 10 doses postoperatively. Surgical complications were assessed from date of surgery through 24 months following study entry.

RESULTS

Early surgical complications were significantly more frequent in the bev group (25.4 vs. 18.9%; trend test p = 0.008), but most were grade 1-2. Early noninfectious wound dehiscences were infrequent and not significantly different (5.4 vs. 3.1%; trend test p = 0.15). Long-term noninfectious wound complications were significantly higher for patients receiving bev (11.8 vs. 5.1%; trend test p = 0.0007), but the incidence of grade ≥3 wound dehiscence was low in both groups (<1%). Among 193 patients undergoing expander or implant reconstructions, 19 (19.6%) of 97 in the bev-receiving group versus 10 (10.4%) of 96 in the non-bev group had grade ≥3 complications (Pearson, p = 0.11).

CONCLUSIONS

Overall, adding bev increased surgical complications, but most serious complications were not significantly increased. In particular, the need for surgical intervention in patients undergoing breast reconstruction with prosthetic implants was higher with bev but was not statistically significantly different. With precautions, bev can be used safely perioperatively in patients undergoing surgery for breast cancer.

SWOG S0800 (NCI CDR0000636131): addition of bevacizumab to neoadjuvant nab-paclitaxel with dose-dense doxorubicin and cyclophosphamide improves pathologic complete response (pCR) rates in inflammatory or locally advanced breast cancer

SWOG S0800, a randomized open-label Phase II clinical trial, compared the combination of weekly nab-paclitaxel and bevacizumab followed by dose-dense doxorubicin and cyclophosphamide (AC) with nab-paclitaxel followed or preceded by AC as neoadjuvant treatment for HER2-negative locally advanced breast cancer (LABC) or inflammatory breast cancer (IBC). Patients were randomly allocated (2:1:1) to three neoadjuvant chemotherapy arms: (1) nab-paclitaxel with concurrent bevacizumab followed by AC; (2) nab-paclitaxel followed by AC; or (3) AC followed by nab-paclitaxel. The primary endpoint was pathologic complete response (pCR) with stratification by disease type (non-IBC LABC vs. IBC) and hormone receptor status (positive vs. negative). Overall survival (OS), event-free survival (EFS), and toxicity were secondary endpoints. Analyses were intent-to-treat comparing bevacizumab to the combined control arms. A total of 215 patients were accrued including 11 % with IBC and 32 % with triple-negative breast cancer (TNBC). The addition of bevacizumab significantly increased the pCR rate overall (36 vs. 21 %; p = 0.019) and in TNBC (59 vs. 29 %; p = 0.014), but not in hormone receptor-positive disease (24 vs. 18 %; p = 0.41). Sequence of administration of nab-paclitaxel and AC did not affect the pCR rate. While no significant differences in OS or EFS were seen, a trend favored the addition of bevacizumab for EFS (p = 0.06) in TNBC. Overall, Grade 3-4 adverse events did not differ substantially by treatment arm. The addition of bevacizumab to nab-paclitaxel prior to dose-dense AC neoadjuvant chemotherapy significantly improved the pCR rate compared to chemotherapy alone in patients with triple-negative LABC/IBC and was accompanied by a trend for improved EFS. This suggests reconsideration of the role of bevacizumab in high-risk triple-negative locally advanced breast cancer.

Phase III Trial Evaluating Letrozole As First-Line Endocrine Therapy With or Without Bevacizumab for the Treatment of Postmenopausal Women With Hormone Receptor-Positive Advanced-Stage Breast Cancer: CALGB 40503 (Alliance)

PURPOSE

To investigate whether anti-vascular endothelial growth factor therapy with bevacizumab prolongs progression-free survival (PFS) when added to first-line letrozole as treatment of hormone receptor-positive metastatic breast cancer (MBC).

PATIENTS AND METHODS

Women with hormone receptor-positive MBC were randomly assigned 1:1 in a multicenter, open-label, phase III trial of letrozole (2.5 mg orally per day) with or without bevacizumab (15 mg/kg intravenously once every 3 weeks) within strata defined by measurable disease and disease-free interval. This trial had 90% power to detect a 50% improvement in median PFS from 6 to 9 months. Using a one-sided α = .025, a target sample size of 352 patients was planned.

RESULTS

From May 2008 to November 2011, 350 women were recruited; 343 received treatment and were observed for efficacy and safety. Median age was 58 years (range, 25 to 87 years). Sixty-two percent had measurable disease, and 45% had de novo MBC. At a median follow-up of 39 months, the addition of bevacizumab resulted in a significant reduction in the hazard of progression (hazard ratio, 0.75; 95% CI, 0.59 to 0.96; P = .016) and a prolongation in median PFS from 15.6 months with letrozole to 20.2 months with letrozole plus bevacizumab. There was no significant difference in overall survival (hazard ratio, 0.87; 95% CI, 0.65 to 1.18; P = .188), with median overall survival of 43.9 months with letrozole versus 47.2 months with letrozole plus bevacizumab. The largest increases in incidence of grade 3 to 4 treatment-related toxicities with the addition of bevacizumab were hypertension (24% v 2%) and proteinuria (11% v 0%).

CONCLUSION

The addition of bevacizumab to letrozole improved PFS in hormone receptor-positive MBC, but this benefit was associated with a markedly increased risk of grade 3 to 4 toxicities. Research on predictive markers will be required to clarify the role of bevacizumab in this setting.

Translating neoadjuvant therapy into survival benefits: one size does not fit all

Neoadjuvant therapy has been established as an effective therapeutic approach for patients with locally advanced breast cancer. Similar outcomes between neoadjuvant and adjuvant chemotherapy have been demonstrated in several trials. Nevertheless, neoadjuvant therapy has some advantages over adjuvant therapy, including tumour downstaging, in vivo assessment of therapeutic efficacy, reduced treatment durations, and the need to enrol fewer patients for clinical trials to reach their preplanned objectives. The number of neoadjuvant trials in patients with breast cancer has increased substantially in the past 5 years, particularly in the context of HER2-positive disease. Substantial improvements in the pathological complete response rate to anti-HER2 therapy, a proposed surrogate end point for long-term clinical benefit, have been observed with neoadjuvant dual-agent HER2 blockade. Thus, it was hypothesized that this approach would provide additional survival benefits over standard-of-care therapy with the anti-HER2 antibody trastuzumab in the adjuvant setting. Emerging data, however, are calling this notion into question. We discuss potential reasons why results of neoadjuvant trials of targeted therapies have not been mirrored in the adjuvant setting, and other than inherent differences in clinical-trial designs and statistical power, we consider how the biology of the disease, patient characteristics, and drug administration and schedule might influence the results.

Neoadjuvant plus adjuvant bevacizumab in early breast cancer (NSABP B-40 [NRG Oncology]): secondary outcomes of a phase 3, randomised controlled trial

BACKGROUND

NSABP B-40 was a 3 × 2 factorial trial testing whether adding capecitabine or gemcitabine to docetaxel followed by doxorubicin plus cyclophosphamide neoadjuvant chemotherapy would improve outcomes in women with operable, HER2-negative breast cancer and whether adding neoadjuvant plus adjuvant bevacizumab to neoadjuvant chemotherapy regimens would also improve outcomes. As reported previously, addition of neoadjuvant bevacizumab increased the proportion of patients achieving a pathological complete response, which was the primary endpoint. We present secondary patient outcomes, including disease-free survival, a specified endpoint by protocol, and data for distant recurrence-free interval, and overall survival, which were not prespecified endpoints but were collected prospectively.

METHODS

In this randomised controlled trial (NSABP B-40), we enrolled women aged 18 years or older, with operable, HER2-non-amplified invasive adenocarcinoma of the breast, 2 cm or greater in diameter by palpation, clinical stage T1c-3, cN0, cN1, or cN2a, without metastatic disease and diagnosed by core needle biopsy. Patients received one of three docetaxel-based neoadjuvant regimens for four cycles: docetaxel alone (100 mg/m(2)) with addition of capecitabine (825 mg/m(2) oral twice daily days 1-14, 75 mg/m(2) docetaxel) or with addition of gemcitabine (1000 mg/m(2) days 1 and 8 intravenously, 75 mg/m(2) docetaxel), all followed by neoadjuvant doxorubicin and cyclophosphamide (60 mg/m(2) and 600 mg/m(2) intravenously) every 3 weeks for four cycles. Those randomly assigned to bevacizumab groups were to receive bevacizumab (15 mg/kg, every 3 weeks for six cycles) with neoadjuvant chemotherapy and postoperatively for ten doses. Randomisation was done (1:1:1:1:1:1) via a biased-coin minimisation procedure to balance the characteristics with respect to clinical nodal status, clinical tumour size, hormone receptor status, and age. Intent-to-treat analyses were done for disease-free survival and overall survival. This study is registered with ClinicalTrials.gov, number NCT00408408.

FINDINGS

Between Jan 5, 2007, and June 30, 2010, 1206 patients were enrolled in the study. Follow-up data were collected from Oct 31, 2007 to March 27, 2014, and were available for overall survival in 1186 patients, disease-free survival in 1184, and distant recurrence-free interval in 1181. Neither capecitabine nor gemcitabine increased disease-free survival or overall survival. Median follow-up was 4·7 years (IQR 4·0-5·2). The addition of bevacizumab significantly increased overall survival (hazard ratio 0·65 [95% CI 0·49-0·88]; p=0·004) but did not significantly increase disease-free survival (0·80 [0·63-1·01]; p=0·06). Four deaths occurred on treatment due to vascular disorder (docetaxel plus capecitabine followed by doxorubicin plus cyclophosphamide group), sudden death (docetaxel plus capecitabine followed by doxorubicin plus cyclophosphamide group), infective endocarditis (docetaxel plus bevacizumab followed by doxorubicin plus cyclophosphamide and bevacizumab group), and visceral arterial ischaemia (docetaxel followed by doxorubicin plus cyclophosphamide group). The most common grade 3-4 adverse events in the bevacizumab group were neutropenia (grade 3, 99 [17%]; grade 4, 37 [6%]), hand-foot syndrome (grade 3, 63 [11%]), and hypertension (grade 3, 60 [10%]; grade 4, two [<1%]) and in the non-bevacizumab group were neutropenia (grade 3, 98 [16%]; grade 4, 36 [6%]), fatigue (grade 3, 53 [9%]), and hand-foot syndrome (grade 3, 43 [7%]).

INTERPRETATION

The addition of gemcitabine or capecitabine to neoadjuvant docetaxel plus doxorubicin plus cyclophosphamide does not seem to provide any benefit to patients with operable breast cancer, and should not change clinical practice in the short term. The improved overall survival with bevacizumab contradicts the findings of other studies of bevacizumab in breast cancer and may indicate the need for additional investigation of this agent.

FUNDING

National Institutes of Health, Genentech, Roche Laboratories, Lilly Research Laboratories, and Precision Therapeutics.

Bevacizumab: a review of its use in advanced cancer

The humanized monoclonal antibody bevacizumab (Avastin(®)) has been available in the EU since 2005. Results of phase III trials demonstrate that adding intravenous bevacizumab to antineoplastic agents improves progression-free survival and/or overall survival in patients with advanced cancer, including when used as first- or second-line therapy in metastatic colorectal cancer, as first-line therapy in advanced nonsquamous non-small cell lung cancer, as first-line therapy in metastatic renal cell carcinoma, as first-line therapy in metastatic breast cancer, and as first-line therapy in epithelial ovarian, fallopian tube or primary peritoneal cancer or in recurrent, platinum-sensitive or platinum-resistant disease. Results of these studies are supported by the findings of routine oncology practice studies conducted in real-world settings. The tolerability profile of bevacizumab is well defined and adverse events associated with its use (e.g. hypertension, proteinuria, haemorrhage, wound healing complications, arterial thromboembolism, gastrointestinal perforation) are generally manageable. In conclusion, bevacizumab remains an important option for use in patients with advanced cancer.

Bevacizumab in Combination with Modified FOLFOX6 in Heavily Pretreated Patients with HER2/Neu-Negative Metastatic Breast Cancer: A Phase II Clinical Trial

BACKGROUND

Bevacizumab combined with modified FOLFOX6 is a standard regimen for colorectal cancer. The present study was to determine the efficacy and safety of bevacizumab-modified FOLFOX6 regimen in heavily pretreated patients with human epidermal growth factor receptor 2 (HER2/neu)-negative MBC.

METHODS

Bevacizumab, 5 mg/kg every two weeks or 7.5 mg/kg every three weeks, was administered with modified FOLFOX6 (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, 5-FU 400 mg/m2 on day 1, followed by 5-FU 2400 mg/m2 intravenous infusion over 46 hours every 2 weeks) to patients who failed at least 1 chemotherapy regimen in the metastatic setting. The primary objective was progression free survival (PFS). Secondary objectives included objective response rate (ORR), clinical benefit rate (CBR), overall survival (OS), safety, and the change of tumor size and Eastern Cooperative Oncology Group (ECOG) performance status.

RESULTS

69 patients were enrolled. The median PFS was 6.8 months (95% CI, 5.0 to 8.5 months), ORR was 50.0% and median OS was 10.5 months (95% CI, 7.9 to 13.1 months). Patients showing objective responses had a 4.2-month median PFS gain and 5.7-month median OS gain compared with those who did not (P < 0.05). Grade 3 or 4 adverse events occurring in more than one patient were neutropenia (53/69, 76.8%), leukopenia (36/69, 52.2%), thrombocytopenia (13/69, 18.8%), anemia (3/69, 4.3%) and hypertension (3/69, 4.3%).

CONCLUSIONS

Adding bevacizumab to modified FOLFOX6 does have significant anti-tumor activity and good safety profile in heavily pretreated HER2/neu-negative MBC patients. Further trials are required to confirm whether the high ORR can translate into a long-term PFS and even OS benefit.

TRIAL REGISTRATION

www.clinicaltrials.gov NCT01658033.

Genome-Wide Association Studies for Taxane-Induced Peripheral Neuropathy in ECOG-5103 and ECOG-1199

PURPOSE

Taxane-induced peripheral neuropathy (TIPN) is an important survivorship issue for many cancer patients. Currently, there are no clinically implemented biomarkers to predict which patients might be at increased risk for TIPN. We present a comprehensive approach to identification of genetic variants to predict TIPN.

EXPERIMENTAL DESIGN

We performed a genome-wide association study (GWAS) in 3,431 patients from the phase III adjuvant breast cancer trial, ECOG-5103 to compare genotypes with TIPN. We performed candidate validation of top SNPs for TIPN in another phase III adjuvant breast cancer trial, ECOG-1199.

RESULTS

When evaluating for grade 3-4 TIPN, 120 SNPs had a P value of <10(-4) from patients of European descent (EA) in ECOG-5103. Thirty candidate SNPs were subsequently tested in ECOG-1199 and SNP rs3125923 was found to be significantly associated with grade 3-4 TIPN (P = 1.7 × 10(-3); OR, 1.8). Race was also a major predictor of TIPN, with patients of African descent (AA) experiencing increased risk of grade 2-4 TIPN (HR, 2.1; P = 5.6 × 10(-16)) and grade 3-4 TIPN (HR, 2.6; P = 1.1 × 10(-11)) compared with others. An SNP in FCAMR, rs1856746, had a trend toward an association with grade 2-4 TIPN in AA patients from the GWAS in ECOG-5103 (OR, 5.5; P = 1.6 × 10(-7)).

CONCLUSIONS

rs3125923 represents a validated SNP to predict grade 3-4 TIPN. Genetically determined AA race represents the most significant predictor of TIPN.

Patients with Slowly Proliferative Early Breast Cancer Have Low Five-Year Recurrence Rates in a Phase III Adjuvant Trial of Capecitabine

PURPOSE

We conducted a randomized phase III study to determine whether patients with early breast cancer would benefit from the addition of capecitabine (X) to a standard regimen of doxorubicin (A) plus cyclophosphamide (C) followed by docetaxel (T).

EXPERIMENTAL DESIGN

Treatment comprised eight cycles of AC→T (T dose: 100 mg/m(2) on day 1) or AC→XT (X dose: 825 mg/m(2) twice daily, days 1-14; T dose: 75 mg/m(2) on day 1). The primary endpoint was 5-year disease-free survival (DFS).

RESULTS

Of 2,611 women, 1,304 were randomly assigned to receive AC→T and 1,307 to receive AC→XT. After a median follow-up of 5 years, the study failed to meet its primary endpoint [HR, 0.84; 95% confidence interval (CI), 0.67-1.05; P = 0.125]. A significant improvement in overall survival, a secondary endpoint, was seen with AC→XT versus AC→T (HR, 0.68; 95% CI, 0.51-0.92; P = 0.011). There were no unexpected adverse events. Of patients with estrogen receptor (ER)-positive/HER2-negative disease, 70% of whom were node-positive, 26% and 59% had tumors with a centrally assessed Ki-67 score of <10% or <20%, respectively, and only 17 (2%) and 53 (6%) DFS events, respectively, occurred in these groups at 7 years.

CONCLUSIONS

The very low event rate in patients with ER-positive, low Ki-67 cancers, regardless of nodal status, strongly suggests that these patients should not be enrolled in adjuvant trials that assess 5-year DFS rates and that central Ki-67 analyses can identify these patients.

Preoperative carboplatin-paclitaxel-bevacizumab in triple-negative breast cancer: final results of the phase II Ca.Pa.Be study

PURPOSE

The phase II Ca.Pa.Be trial evaluated preoperative carboplatin-paclitaxel in combination with bevacizumab in triple-negative breast cancer patients with previously untreated stage II-III disease. The primary aim was the assessment of the rate of pathologic complete response (pCR). Secondary aims included safety, breast-conserving surgery rate, and early response assessment with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).

METHODS

Patients with hormone receptor-negative, HER-2-negative stage II-III breast cancer were eligible. Treatment included paclitaxel 80 mg/mq + carboplatin area under the curve (AUC) 2 on days 1, 8, and 15, combined with bevacizumab 10 mg/kg on days 1 and 15 each 28 days, for 5 courses. At baseline, patients underwent breast DCE-MRI, followed by a single dose of bevacizumab 5 mg/kg (day -6). DCE-MRI was repeated before the initiation of chemotherapy.

RESULTS

Forty-four patients were enrolled. Forty-three patients underwent surgery, and 22 (50 %) received breast-conserving surgery (conversion rate from mastectomy indication at baseline, 34.4 %). A pCR in breast and axillary lymph nodes occurred in 22 patients (50 %). Bevacizumab-associated adverse events (AEs) were mild: G1-2 hypertension and bleeding occurred in 6 (13.6 %) and 12 (27 %) patients, respectively. No G4 nonhematologic AEs were recorded. More frequent G3 AEs were liver function test abnormalities (6.8 %), and diarrhea and fatigue (4.5 % each). The only G3-4 hematologic toxicity was neutropenia (G3, 25 %; G4, 9 %). Early assessed DCE-MRI response parameters failed to predict pCR.

CONCLUSIONS

The neoadjuvant anthracycline-free combination of weekly paclitaxel and carboplatin plus bevacizumab is active and safe in triple-negative breast cancer, and the rate of pCR is comparable to that observed with more intensive carboplatin- and bevacizumab-containing regimens. Further investigation is warranted.

Cardiovascular toxicities from systemic breast cancer therapy

Cardiovascular toxicity is unfortunately a potential short- or long-term sequela of breast cancer therapy. Both conventional chemotherapeutic agents such as anthracyclines and newer targeted agents such as trastuzumab can cause varying degrees of cardiac dysfunction. Type I cardiac toxicity is dose-dependent and irreversible, whereas Type II is not dose-dependent and is generally reversible with cessation of the drug. In this review, we discuss what is currently known about the cardiovascular effects of systemic breast cancer treatments, with a focus on the putative mechanisms of toxicity, the role of biomarkers, and potential methods of preventing and minimizing cardiovascular complications.

Impact of the addition of carboplatin and/or bevacizumab to neoadjuvant once-per-week paclitaxel followed by dose-dense doxorubicin and cyclophosphamide on pathologic complete response rates in stage II to III triple-negative breast cancer: CALGB 40603 (Alliance)

PURPOSE

One third of patients with triple-negative breast cancer (TNBC) achieve pathologic complete response (pCR) with standard neoadjuvant chemotherapy (NACT). CALGB 40603 (Alliance), a 2 × 2 factorial, open-label, randomized phase II trial, evaluated the impact of adding carboplatin and/or bevacizumab.

PATIENTS AND METHODS

Patients (N = 443) with stage II to III TNBC received paclitaxel 80 mg/m(2) once per week (wP) for 12 weeks, followed by doxorubicin plus cyclophosphamide once every 2 weeks (ddAC) for four cycles, and were randomly assigned to concurrent carboplatin (area under curve 6) once every 3 weeks for four cycles and/or bevacizumab 10 mg/kg once every 2 weeks for nine cycles. Effects of adding these agents on pCR breast (ypT0/is), pCR breast/axilla (ypT0/isN0), treatment delivery, and toxicities were analyzed.

RESULTS

Patients assigned to either carboplatin or bevacizumab were less likely to complete wP and ddAC without skipped doses, dose modification, or early discontinuation resulting from toxicity. Grade ≥ 3 neutropenia and thrombocytopenia were more common with carboplatin, as were hypertension, infection, thromboembolic events, bleeding, and postoperative complications with bevacizumab. Employing one-sided P values, addition of either carboplatin (60% v 44%; P = .0018) or bevacizumab (59% v 48%; P = .0089) significantly increased pCR breast, whereas only carboplatin (54% v 41%; P = .0029) significantly raised pCR breast/axilla. More-than-additive interactions between the two agents could not be demonstrated.

CONCLUSION

In stage II to III TNBC, addition of either carboplatin or bevacizumab to NACT increased pCR rates, but whether this will improve relapse-free or overall survival is unknown. Given results from recently reported adjuvant trials, further investigation of bevacizumab in this setting is unlikely, but the role of carboplatin could be evaluated in definitive studies, ideally limited to biologically defined patient subsets most likely to benefit from this agent.