Benefit from anthracyclines in relation to biological profiles in early breast cancer

The impact of progesterone receptor expression on prognosis of patients with rapidly proliferating, hormone receptor-positive early breast cancer: a post hoc analysis of the IBIS 3 trial

Background

In the Italian Breast Cancer Intergroup Studies (IBIS) 3 phase III trial, we compared cyclophosphamide, methotrexate, 5-fluorouracil (CMF) alone to sequential epirubicin/CMF regimens in patients with rapidly proliferating early breast cancer (RPEBC). We performed a post hoc analysis in the subgroup of patients with hormone-receptor-positive RPEBC on the prognostic role of progesterone receptor (PgR) status.

Methods

RPEBC was defined by thymidine labeling index (TLI) >3% or grade 3 or S-phase >10% or Ki67 >20%. We analyzed 466 patients with hormone-receptor-positive RPEBC receiving sequential epirubicin/CMF regimens followed by tamoxifen, and for whom the status of ER and PgR was available.

Results

Considering both cut-off values of 10% and 20%, PgR expression was significantly associated with age, menopausal status, and ER expression; HER2 status was associated with PgR status only at a cutoff value of 20% PgR. Upon univariate analysis, tumor size, nodal status, and PgR were significantly associated with disease-free survival (DFS) and overall survival (OS), while age class and local treatment type were associated only with DFS. Patients with PgR <20% showed lower 5- and 10-year DFS [hazard ratio (HR) = 1.48; 95%CI: 1.01-2.18; p = 0.044] and OS (HR = 1.85; 95%CI: 1.08-3.19, p = 0.025) rates compared with patients with PgR ⩾20%. Upon multivariate analysis, only tumor size, nodal status, and PgR were independent prognostic factors.

Conclusions

Our results highlight the independent prognostic relevance of PgR expression in patients with hormone-receptor-positive RPEBC treated with adjuvant chemotherapy and endocrine therapy, where the definition of prognostic subgroups is still a major need.

Real-life clinical pattern, management, and survival in Thai patients with early-stage or metastatic triple-negative breast cancer

OBJECTIVES

To characterize the clinical pattern and evaluate real-life practices in the management of patients with triple-negative breast cancer (TNBC) in Thailand.

METHODS

In this multicenter, prospective, observational cohort, females (aged ≥18 years) with histologically and immunohistochemically confirmed TNBC were enrolled. Patient data was collected at four study visits-an inclusion visit (for enrollment), and three subsequent follow-up visits at 12±1, 24±1, and 36±1 months after completion of first day of any planned chemotherapy.

RESULTS

Of the 293 enrolled patients, 262 (89.4%) had early-stage TNBC (Stage I: 46 patients, Stage II: 151 patients, and Stage III: 65 patients) and 31 (10.6%) had metastatic TNBC (mTNBC). Chemotherapy was prescribed to 95.4% of the early-stage patients and to 100.0% of the mTNBC patients; most commonly as anthracycline-based in combination with cyclophosphamide and other agents. Patients' performance status and consensus guidelines were the major factors affecting choice of treatment. In early-stage patients, median disease-free survival (DFS) and overall survival (OS) had not been reached for Stage I and II patients, and were calculated to be 37.0 months and 40.0 months, respectively, in Stage III patients. In mTNBC patients, progression-free survival (PFS) and OS were found to be 10.0 months and 14.0 months, respectively. In Stage III patients, anthracycline-based regimens were found to be associated with increase in DFS (p = 0.0181) and OS (p = 0.0027) compared to non-anthracycline-based regimens. In mTNBC patients, non-taxane-based regimens were associated with an increase in PFS (p = 0.0025). The 3-year survival rates in early-stage and mTNBC patients were 85.0% and 21.0%, respectively.

CONCLUSION

Clinical management of TNBC in Thailand follows the general guidelines for treatment of TNBC. However, prognosis and survival outcomes are suboptimal, especially in progressive disease. This study is the first assessment in the existing practices in which the results could pave to way to improve the treatment outcome of TNBC in Thailand.

Herceptin® (trastuzumab) in HER2-positive early breast cancer: a systematic review and cumulative network meta-analysis

BACKGROUND

Originator trastuzumab (Herceptin®; H) is an antibody-targeted therapy to treat patients with human epidermal growth factor receptor 2-positive (HER2+) early breast cancer (EBC). We investigated the overall survival (OS) advantage conferred by the addition of H to chemotherapy for HER2+ EBC patients and how the OS advantage changed over time.

METHODS

A systematic literature review (SLR) identified randomized controlled trials (RCTs) and non-randomized studies (NRSs) published from January 1, 1990 to January 19, 2017, comparing systemic therapies used in the neoadjuvant/adjuvant settings to treat HER2+ EBC patients. Bayesian cumulative network meta-analyses (cNMAs) of OS were conducted to assess the published literature over time. Heterogeneity was assessed through sensitivity and subgroup analyses.

RESULTS

The SLR identified 31 unique studies (28 RCTs, 3 NRSs) included in the OS analyses from 2008 to 2016. In the reference case cNMA (RCTs alone), initial evidence demonstrated an OS advantage for H/chemotherapy compared with chemotherapy alone in HER2+ EBC patients. As additional OS data were published, the precision around this survival benefit strengthened over time. Both H/anthracycline-containing chemotherapy and H/non-anthracycline-containing chemotherapy regimens provided similar OS advantages for HER2+ EBC patients.

CONCLUSION

This analysis represents the most comprehensive SLR/cNMA to date of published OS data in HER2+ EBC studies. These findings demonstrate why H/chemotherapy is now the established standard of care in HER2+ EBC. In the case of H, the benefits of early patient access far outweighed the risk of waiting for more precise information.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017055763.

Androgen and oestrogen receptors as potential prognostic markers for patients with ductal carcinoma in situ treated with surgery and radiotherapy

Ductal carcinoma in situ (DCIS) is a heterogeneous disease that has been investigated less extensively than invasive breast cancer. Women with DCIS are mainly treated with conservative surgery almost exclusively followed by radiotherapy. However, as radiation treatment is not always effective, the search for biomarkers capable of identifying DCIS lesions that could progress to invasive cancer is ongoing. Although conventional biomarkers have been thoroughly studied in invasive tumours, little is known about the role played by androgen receptor (AR), widely expressed in DCIS. A series of 42 DCIS patients treated with quadrantectomy and radiotherapy were followed for a period of up to 95 months. Of these, 11 had recurrent DCIS or progressed to invasive cancer. All tumours were analysed for clinical pathological features. Conventional biomarkers and androgen receptor expression were determined by immunohistochemistry. Our results showed that AR was higher in tumours of relapsed patients than non-relapsed patients (P value: 0.0005). Conversely, oestrogen receptor (ER) was higher, albeit not significantly, in non-relapsed patients than in relapsed patients. AR/ER ratio was considerably different in the two subgroups (P value: 0.0033). Area under the curve (AUC) values were 0.85 for AR and 0.80 for the AR/ER ratio. These preliminary results highlight the potentially important role of both AR and the AR/ER ratio as prognostic markers in DCIS.

Effect of antitumor treatments on triple-negative breast cancer patients: A PRISMA-compliant network meta-analysis of randomized controlled trials

BACKGROUND

Triple-negative breast cancer (TNBC) lacks the expression of the estrogen receptor, progesterone receptor, and receptor tyrosine-protein kinase erbB-2 (HER2/neu), which renders hormone-related endocrine and targeted therapy essentially futile.

OBJECTIVE

We performed a meta-analysis to assess the effects of antitumor regimens in the treatment of TNBC patients.

METHODS

We searched electronic databases, including PubMed, Embase, and the Cochrane Library, through January 2017 using the following keywords: "triple negative breast cancer," "TNBC," and "random*" without language restrictions. The major outcome in the present analysis was the overall response rate (ORR), and the secondary outcomes were progression-free survival (PFS) and overall survival (OS). A network meta-analysis and multilevel mixed-effects logistic regression were used to compare antitumor regimens.

RESULTS

We included 35 articles assessing a total of 8476 TNBC patients in our systematic review. The regimen of Bevacizumab, Carboplatin, and Paclitaxel (78.2%) was the most likely to improve the ORR in TNBC patients, followed by EndoTAG-1 and Paclitaxel (69.7%), Carboplatin and Paclitaxel (65.0%), and Bevacizumab and Paclitaxel (61.8%). In the patients without metastasis, the regimen of Bevacizumab, Carboplatin, and Paclitaxel (74.9%) remained the most likely to improve the ORR. We could not analyze the results for patients with metastasis or outcomes of PFS and OS because no >4 regimens formed a network. In the regression analysis, Bevacizumab (odds ratio [OR], 1.71; 95% confidence interval [CI], 1.43-2.05; P < .001) and Carboplatin (OR, 2.07; 95% CI, 1.62-2.64; P < .001) correlated with superior ORR outcome, and Iniparib (OR, 1.51; 95% CI, 1.11-2.07; P = .009) correlated with superior OS outcome.

CONCLUSION

The regimen including Bevacizumab, Carboplatin, and Paclitaxel was the most likely to improve the ORR in TNBC patients and in advanced metastatic TNBC patients. The administration of Bevacizumab and Carboplatin provided greater benefit toward improved patient ORR.

The Predictive Value of PITX2 DNA Methylation for High-Risk Breast Cancer Therapy: Current Guidelines, Medical Needs, and Challenges

High-risk breast cancer comprises distinct tumor entities such as triple-negative breast cancer (TNBC) which is characterized by lack of estrogen (ER) and progesterone (PR) and the HER2 receptor and breast malignancies which have spread to more than three lymph nodes. For such patients, current (inter)national guidelines recommend anthracycline-based chemotherapy as the standard of care, but not all patients do equally benefit from such a chemotherapy. To further improve therapy decision-making, predictive biomarkers are of high, so far unmet, medical need. In this respect, predictive biomarkers would permit patient selection for a particular kind of chemotherapy and, by this, guide physicians to optimize the treatment plan for each patient individually. Besides DNA mutations, DNA methylation as a patient selection marker has received increasing clinical attention. For instance, significant evidence has accumulated that methylation of the PITX2 (paired-like homeodomain transcription factor 2) gene might serve as a novel predictive and prognostic biomarker, for a variety of cancer diseases. This review highlights the current understanding of treatment modalities of high-risk breast cancer patients with a focus on recommended treatment options, with special attention on the future clinical application of PITX2 as a predictive biomarker to personalize breast cancer management.

PREDICTIVE CIRCULATING MARKERS FOR ANTHRACYCLINE CHEMOTHERAPY IN NON-METASTATIC BREAST CANCER

Anthracyclines are used in breast cancer both in early and advanced stages and their recommendation together with taxanes, either concurrently or sequentially, is debatable and individualized by phenotype. Circulating biomarkers have already been introduced in clinical practice for metastatic disease monitoring. We questioned whether it might be a role for these markers in neoadjuvant and adjuvant settings too and a general review was conducted. CK18 and CTC were found predictive for anthracycline related response in preoperative setting. Soluble E-cadherin is promising, a retrospective analysis showing a direct correlation with clinical response. CEA, CA 15-3 and HER2 ECD are not of interest for their predictive role.

Biologic subtype is a more important prognostic factor than nodal involvement in patients with stages I and II breast carcinoma

Purpose

Nodal infiltration has been one of the most important prognostic factors in breast cancer. In recent decades, risk stratification has greatly changed, and is applied in accordance with hormone receptor and human epidermal growth factor receptor 2 (HER2) status. We compared the prognostic power of tumor subtype to nodal involvement in early breast cancer.

Methods

We reviewed the medical records of 505 patients who had curative surgery for stage I or II breast cancer. We analyzed clinicopathologic factors according to tumor subtype and nodal involvement. Tumors were classified into 4 subtypes according to immunohistochemical status of estrogen receptor, progesterone receptor, HER2, and Ki67 labeling index. Disease-free survival (DFS) and overall survival were analyzed.

Results

There were 363 node-negative patients (71.9%) and 142 node-positive patients (28.1%). Luminal A, Luminal B, HER2, and triple-negative breast cancer subtypes were composed of 207 (41.0%), 147 (29.1%), 42 (8.3%), and 109 patients (21.6%), respectively. The median follow-up period was 89.5 months. Node negative-luminal A subtype showed the best prognosis with regard to 5-year DFS, and the pN1-triple negative subtype was associated with the shortest DFS (95.1% vs. 67.8%; hazard ratio, 9.554; P < 0.001). However, the node negative-triple negative subtype was associated with a worse 5-year DFS than the pN1-luminal A subtype ([86.4%; hazard ratio, 2.647; P = 0.048] vs. [93.2%; hazard ratio, 2.061; P = 0.194]).

Conclusion

Node negative-triple negative breast cancer was associated with a poorer prognosis than pN1-luminal A subtype. Tumor subtype has greater prognostic power compared to nodal status in early breast cancer.

Role of androgen and estrogen receptors as prognostic and potential predictive markers of ductal carcinoma in situ of the breast

BACKGROUND

Ductal carcinoma in situ (DCIS) is a heterogeneous disease that has not been investigated as widely as invasive breast cancer. Thus, the search for biomarkers capable of identifying DCIS lesions that may recur or progress to invasive cancer is ongoing. Although conventional steroid hormone receptors, cell proliferation and other important tumor markers have been extensively studied in invasive tumors, little is known about the role played by androgen receptors (ARs), widely expressed in breast cancer, in DCIS.

METHODS

We performed a retrospective study in a series of 43 DCIS patients treated with quadrantectomy only and followed up for a period ranging from 5 to 13 years, to evaluate the prognostic relevance of conventional biomarkers (estrogen receptor [ER], progesterone receptor [PgR], Ki67, human epidermal growth factor receptor 2 [HER2]) and AR.

RESULTS

Our findings showed that AR and ER were not independent prognostic variables and that an AR/ER ratio cutoff of 1.13 showed a sensitivity of 75% and a specificity of 94% in predicting in situ relapse or progression to the invasive phenotype. Moreover, while the variables considered singly showed area under the curve (AUC) values ranging from 0.52% to 0.77%, the AR/ER ratio reached a very high AUC (0.92%).

CONCLUSIONS

These preliminary results highlight the potentially important role of AR and ER and, in particular, of their ratio, as prognostic indicators of DCIS evolution.

Prognostic value of different cut-off levels of Ki-67 in breast cancer: a systematic review and meta-analysis of 64,196 patients

A proliferative marker, expressed as the percentage of cells in a cell cycle, has been developed and used as a discriminant of more aggressive malignant phenotypes in early breast cancer (BC). The marker is usually expressed by the immunohistochemical staining of the cell cycle antigen Ki-67. It has not, however, yet been definitely evaluated, due to methodological concerns, which specific Ki-67 cut-off provide the strongest prognostic information in resected BC. We conducted a meta-analysis to explore the prognostic value of different cut-off levels of Ki-67 in terms of overall survival (OS) and disease-free survival (DFS) in early BC. The databases of PubMed, the ISI Web of Science, EMBASE, SCOPUS, the Cochrane Central Register of Controlled Trials, and CINHAL were used to identify the relevant literature. Data from studies reporting a hazard ratio (HR) and a 95 % confidence interval (CI) calculated as a multivariate analysis were pooled in a meta-analysis, with metaregression used to test for trends in predefined subgroups. All the statistical tests were 2-sided. Forty-one studies encompassing 64,196 BC patients were included in the analysis. Overall, n = 25 studies were available for the OS analysis. The pooled HR for high versus low Ki-67 was 1.57 (95 % CI 1.33-1.87, P < 0.00001). Twenty-nine studies were available for the DFS analysis. The pooled HR for high versus low Ki-67 was 1.50 (95 % CI 1.34-1.69, P < 0.00001). When a cut-off of Ki-67 staining ≥ 25 % was used, the pooled HR for OS was 2.05 (95 % CI 1.66-2.53, P < 0.00001), which was significantly different to studies where the cut-offs chosen were <25 %. In ER+ tumors, the HR for high versus low Ki-67 was similar and significant (HR = 1.51, 95 % CI 1.25-1.81, P < 0.0001). We conclude that Ki-67 has an independent prognostic value in terms of OS in BC patients. The Ki-67 threshold with the greatest prognostic significance is as yet unknown, but a cut-off >25 % is associated with a greater risk of death compared with lower expression rates.

Time to initiation of adjuvant chemotherapy in patients with rapidly proliferating early breast cancer

AIM

To evaluate the optimal time interval from definitive surgery to commencing chemotherapy in early breast cancer (EBC).

PATIENTS AND METHODS

The relationship between time to initiation of adjuvant chemotherapy (TTC), calculated in weeks, and disease-free (DFS) or overall survival (OS), was assessed in 921 EBC patients with rapidly proliferating tumours (thymidine labelling index >3% or G3 or Ki67 >20%), randomised in a phase III clinical trial (NCT01031030) to receive chemotherapy with or without anthracyclines (epirubicin→cyclophosphamide, methotrexate and fluorouracil (CMF) versus CMF→epirubicin versus CMF). DFS, OS and 95% confidence intervals (95% confidence interval (CI)) were calculated by the Kaplan-Meier method. Multivariate Cox analysis was performed in relation with nodal involvement, oestrogen receptor and human epidermal growth factor receptor 2 (HER2) status, Ki67 value, type of adjuvant chemotherapy, menopausal status and tumour size.

RESULTS

At a median follow-up of 105 months (range 2-188), a prolonged TTC resulted in a significant increase in the risk of relapse: hazard ratio (HR) 1.15 (95% CI 1.02-1.30, p=0.019). Using a backward elimination procedure, TTC, tumour size and nodal involvement remained significantly associated with DFS. A time-dependent receiver-operating characteristic (ROC) curve analysis was subsequently utilised to evaluate the best cut-off for TTC, identifying 7 weeks as the best threshold for longer OS (p=0.043): 8-year OS 88% (95% CI 85-90) for patients with a TTC <7 weeks and 78% (95% CI 68-87) for the other group.

CONCLUSIONS

Our results confirm that a shorter TTC may reduce relapses and possibly also improve clinical outcome in patients with highly proliferating EBC.

Ki-67 as a Prognostic Factor in Feline Mammary Carcinoma: What Is the Optimal Cutoff Value?

Ki-67 is a nuclear protein and a proliferation marker frequently used in establishing the prognosis for breast cancer patients. To investigate the prognostic value of the Ki-67 proliferation index in female cats with mammary carcinoma, a prospective study was conducted with 96 animals. The Ki-67 index of primary tumors (n = 96) was initially determined, and whenever possible, the Ki-67 index of regional lymph node metastasis (n = 38) and distant metastasis (n = 16) was also estimated. The optimal cutoff value for the Ki-67 index was determined by univariate and multivariate analysis. Ki-67 indices ≥ 14% were detected in 72.9% (70 of 96) of the tumors. Tumors with a Ki-67 index ≥ 14% were significantly associated with large size (P = .022), poor differentiation (P = .009), presence of necrotic areas (P = .008), estrogen receptor-negative status (P < .0001), fHER2-negative status (P = .003), and shorter overall survival (P = .012). Moreover, Ki-67 expression in the primary tumor was strongly and positively correlated with both regional metastasis (P < .0001; r = 0.83) and distant metastasis (P < .0001; r = 0.83), and was significantly higher in distant metastases when compared with the primary tumor (P = .0009). A similar correlation was also observed between regional and distant metastasis (P < .0001; r = 0.75). On the basis of the above results, the authors propose the adoption of the 14% value as the optimal cutoff for Ki-67 to identify tumors with high risk of disease progression.

Adjuvant chemotherapy for early female breast cancer: a systematic review of the evidence for the 2014 Cancer Care Ontario systemic therapy guideline

BACKGROUND

The Program in Evidence-Based Care (pebc) of Cancer Care Ontario recently created an evidence-based consensus guideline on the systemic treatment of early breast cancer. The evidence for the guideline was compiled using a systematic review to answer the question "What is the optimal systemic therapy for patients with early-stage, operable breast cancer, when patient and disease factors are considered?" The question was addressed in three parts: cytotoxic chemotherapy, endocrine treatment, and human epidermal growth factor receptor 2 (her2)-directed therapy.

METHODS

For the systematic review, the medline and embase databases were searched for the period January 2008 to May 2014. The Standards and Guidelines Evidence directory of cancer guidelines and the Web sites of major oncology guideline organizations were also searched. The basic search terms were "breast cancer" and "systemic therapy" (chemotherapy, endocrine therapy, targeted agents, ovarian suppression), and results were limited to randomized controlled trials (rcts), guidelines, systematic reviews, and meta-analyses.

RESULTS

Several hundred documents that met the inclusion criteria were retrieved. The Early Breast Cancer Trialists' Collaborative Group meta-analyses encompassed many of the rcts found. Several additional studies that met the inclusion criteria were retained, as were other guidelines and systematic reviews. Chemotherapy was reviewed mainly in three classes: anti-metabolite-based regimens (for example, cyclophosphamide-methotrexate-5-fluorouracil), anthracyclines, and taxane-based regimens. In general, single-agent chemotherapy is not recommended for the adjuvant treatment of breast cancer in any patient population. Anthracycline-taxane-based polychemotherapy regimens are, overall, considered superior to earlier-generation regimens and have the most significant impact on patient survival outcomes. Regimens with varying anthracycline and taxane doses and schedules are options; in general, paclitaxel given every 3 weeks is inferior. Evidence does not support the use of bevacizumab in the adjuvant setting; other systemic therapy agents such as metformin and vaccines remain investigatory. Adjuvant bisphosphonates for menopausal women will be discussed in later work.

CONCLUSIONS

The results of this systematic review constitute a comprehensive compilation of the high-level evidence that is the basis for the 2014 pebc guideline on systemic therapy for early breast cancer. Use of cytotoxic chemotherapy is presented here; the results addressing endocrine therapy and her2-targeted treatment, and the final clinical practice recommendations, are published separately in this supplement.