Survival among women with triple receptor-negative breast cancer and brain metastases

The paradox of triple negative breast cancer: novel approaches to treatment

Breast cancer that lacks expression of estrogen/progesterone receptors and overexpression of the human epidermal growth factor receptor2 (HER2), i.e. triple-negative breast cancer (TNBC), is not amenable to current targeted therapies and carries a poor prognosis. This review discusses the natural history of TNBC and published literature in the relevant treatment landscape, with a focus on newer therapies. Compared with other subtypes of breast cancer, TN tumors have higher response rates to neoadjuvant chemotherapy; however, this advantage is not clearly translated into the metastatic setting and has not improved these patients' overall survival. Numerous cytotoxic and targeted strategies have demonstrated efficacy or are under investigation. Strategies showing promise in this difficult-to-treat group of patients include cytotoxic therapy with platinum-containing agents, ixabepilone, and novel targeted approaches such as poly(ADP-ribose) polymerase inhibitors.

Emerging trends in the treatment of triple-negative breast cancer in Canada: a survey

Triple-negative breast cancer (TNBC) has a poor prognosis compared to other subtypes and lacks common therapeutic targets, including HER 2 and the estrogen and progesterone receptors. The clinicopathological heterogeneity of the disease and limited treatment options make clinical management particularly challenging. Here we present the results of a survey of Canadian clinical oncologists regarding treatment of TNBC, and review recent and ongoing clinical research in this area. Our survey results show that the majority of respondents use a combination of anthracyclines-taxanes as adjuvant therapy for early TNBC. For the first-line treatment of metastatic TNBC, most clinicians recommend taxanes, while single agent capecitabine and platinum-based therapies are more common for subsequent lines of therapy. Despite the ongoing development of novel targeted therapies, chemotherapy remains the mainstay of treatment for TNBC.

Brain metastases from breast cancer: proposition of new prognostic score including molecular subtypes and treatment

To develop a specific prognostic score for patients with brain metastases (BM) from breast cancer (BC), including the BC molecular subtype and treatment parameters, we analyzed the outcome of 130 patients with BM from BC who received whole-brain radiotherapy. We identified hierarchical risk groups for estimated survival by using recursive partitioning analysis (RPA). Seven prognostic factors, namely performance status, age, trastuzumab-based therapy for HER-2-overexpressing tumors, a triple-negative phenotype, Scarff-Bloom-Richardson grade, the serum LDH level and the lymphocyte count at BM diagnosis, were incorporated in the RPA. The final RPA nodes were grouped according to the survival time. The RPA tree showed that survival was best (median 19.5 months) among patients with HER2-overexpressing tumors who received trastuzumab-based therapy. The worst survival (median 3.5 months) was observed among patients who did not receive trastuzumab and who had lymphopenia at BM diagnosis, or KPS <70 and age over 50 years, or KPS ≥70 and a triple-negative tumor (HR- & HER-2-). The other patients had a median survival of 12.5 months (P < 0.001). This 3-class specific prognostic score successfully predicted the outcomes of a heterogeneous group of patients with brain metastases from BC.

Triple-negative breast cancer: adjuvant therapeutic options

Triple-negative breast cancer (TNBC), a subtype distinguished by negative immunohistochemical assays for expression of the estrogen and progesterone receptors (ER/PR) and human epidermal growth factor receptor-2(HER2) represents 15% of all breast cancers. Patients with TNBC generally experience a more aggressive clinical course with increased risk of disease progression and poorer overall survival. Furthermore, this subtype accounts for a disproportionate number of disease-related mortality in part due to its aggressive natural history and our lack of effective targeted agents beyond conventional cytotoxic chemotherapy. In this paper, we will review the epidemiology, risk factors, prognosis, and the molecular and clinicopathologic features that distinguish TNBC from other subtypes of breast cancer. In addition, we will examine the available data for the use of cytotoxic chemotherapy in the treatment of TNBC in both the neoadjuvant and adjuvant setting and explore the ongoing development of newer targeted agents.

Management of patients with brain metastases receiving trastuzumab treatment for metastatic breast cancer

BACKGROUND

With the more effective control of visceral metastases in patients with metastatic breast cancer (MBC), an increasing number of patients face brain metastases (BM). The aim of this retrospective analysis was to investigate the incidence and factors affecting the prognosis of patients with BM under trastuzumab treatment for MBC.

PATIENTS AND METHODS

A total of 75 HER2positive patients treated with trastuzumab for MBC were included. RESULTS are discussed in the context of the current literature.

RESULTS

Patients who developed BM (n = 29) had longer median progression-free survival (PFS) during first-line chemotherapy and longer overall survival (OS) after diagnosis of MBC than 46 patients without BM (PFS: 27 vs. 14 months, p = 0.039; OS: 46 vs. 18 months, p = 0.067). Median survival of patients with continuation of trastuzumab after diagnosis of BM was longer than survival of patients with discontinuation of trastuzumab treatment after BM (18 vs. 3 months, p = 0.006). Survival of patients who were treated with surgery and radiotherapy for BM was better compared with radiotherapy alone (9 vs. 5 months, p = not significant) or best supportive care (9 vs. 2 months, p = 0.049).

CONCLUSIONS

Continuation of trastuzumab treatment as well as resection of BM seem to give further benefit in the treatment of patients with HER2-overexpressing MBC.

[Brain metastases from breast cancer: usefulness and limits of prognostic scores]

Approximately 10 to 30% of patients with metastatic breast cancer will develop brain metastases (BM) during the disease course. Whole-brain radiation therapy (WBRT) is considered the standard treatment for most patients, particularly those with extensive intracranial disease, providing symptom relief and increasing median and overall survival. Despite WBRT, the prognosis for the general population of patients with BM remains poor, with a median survival time of approximately five months. Several studies have examined the relative contributions of patient characteristics to survival and have attempted to identify subgroups of patients with substantially different outcomes in order to tailor therapy and to influence the design, stratification and interpretation of future clinical trials. This review examines prognostic scores and their validation in patients with BM from breast carcinoma. We also discuss the prognostic value of specific parameters for breast carcinoma, such as tumor HR status, HER2 over-expression or specific treatment parameters, and the value and limits of these prognostic scores in clinical practice.

Triple-negative breast cancer in Hispanic patients: high prevalence, poor prognosis, and association with menopausal status, body mass index, and parity

BACKGROUND

Triple-negative breast cancer (TNBC) is defined as breast cancer that is negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. TNBC represents 15% of all invasive breast cancers, but some studies have suggested that its prevalence differs between races. To the authors' knowledge, no previous studies have determined the prevalence of TNBC and its risk factors among Hispanic women.

METHODS

The authors identified 2074 Hispanic women with breast cancer who attended the National Cancer Institute in Mexico City from 1998 to 2008. All histopathologic and immunohistochemical diagnoses were rereviewed by a breast cancer pathologist. The prevalence of TNBC, its association with clinicopathologic characteristics, and its prognostic impact were determined.

RESULTS

The median patient age at diagnosis (±standard deviation) was 50 ± 12 years. The overall prevalence of TNBC was 23.1%. Younger age (P < .001), premenopausal status (P = .002), increased parity (P = .029), hormonal contraceptive use (P = .04) high histologic grade (P < .001), and advanced disease (P < .001) were associated independently with TNBC. Postmenopausal patients who had a body mass index (BMI) <25 kg/m(2) (P = .027) or <30 kg/m(2) (P < .001) were more likely to have TNBC. In multivariate analysis, patients with TNBC had a higher risk of locoregional recurrence (LRR), lower disease-free survival (DFS) (hazard ratio, 1.62; 95% confidence interval, 1.13-2.32; P = .009), and a lower cancer-specific survival (CSS) rate (hazard ratio, 1.66; 95% confidence interval, 1.20-2.30; P = .002) than patients with non-TNBC.

CONCLUSIONS

The median age at diagnosis of Hispanic women with breast cancer was 11 years younger than the average age reported in the United States. The prevalence of TNBC in this study population was higher than that reported in white women with breast cancer. TNBC was associated with a higher risk of LRR and with lower DFS and CSS than those in patients with non-TNBC.

Triple-negative breast cancer: epidemiology and management options

The triple receptor-negative breast cancer (TNBC) subtype is characterized by the lack of expression of both hormone receptors as well as lack of over-expression and/or lack of gene amplification of human epidermal growth factor receptor 2 (HER2). Approximately 10-15% of breast carcinomas are known to be of the TNBC subtype, which constitutes approximately 80% of all 'basal-like tumours'. Risk factors for TNBC include young age at breast cancer diagnosis, young age at menarche, high parity, lack of breast feeding, high body mass index and African American ethnicity. The majority of BRCA1 tumours are TNBC. TNBC has a worse prognosis and tends to relapse early compared with other subtypes of breast cancer. Conversely, it displays increased chemosensitivity compared with other breast tumour subtypes. Several agents are currently being investigated as potential therapeutic agents for the treatment of women with TNBC including agents targeted against EGFR, anti-angiogenic agents, multityrosine kinase inhibitors and poly (ADP-ribose) polymerase (PARP) inhibitors. This review focuses on the epidemiology of TNBC, its pathological features, natural history and recurrence patterns as well as current and future management options.

Minireview: Basal-like breast cancer: from molecular profiles to targeted therapies

The classification of breast cancer into molecular subtypes with distinctive gene expression signatures that predict treatment response and prognosis has ushered in a new era of personalized medicine for this remarkably heterogeneous and deadly disease. Basal-like breast cancer (BLBC) is a particularly aggressive molecular subtype defined by a robust cluster of genes expressed by epithelial cells in the basal or outer layer of the adult mammary gland. BLBC is a major clinical challenge because these tumors are prevalent in young woman, often relapsing rapidly. Additionally, most (but not all) basal-like tumors lack expression of steroid hormone receptors (estrogen receptor and progesterone receptor) and human epidermal growth factor receptor 2, limiting targeted therapeutic options for these predominantly triple-negative breast cancers. This minireview will focus on new insights into the molecular etiology of these poor-prognosis tumors that underlie their intrinsic genomic instability, deregulated cell proliferation and apoptosis, and invasive tumor biology. We will also review ongoing efforts to translate these fundamental insights into improved therapies for women with BLBC.

Multifactorial central nervous system recurrence susceptibility in patients with HER2-positive breast cancer: epidemiological and clinical data from a population-based cancer registry study

BACKGROUND

A series of retrospective studies have reported that patients with human epidermal growth factor receptor 2(HER2)-positive breast cancer are at a greater risk of central nervous system (CNS) metastases. Trastuzumab, which does not cross the blood-brain barrier, has been associated with this increased risk.

METHODS

The authors evaluated incidence, survival, and risk factors for CNS metastases in the incident breast cancer population systematically collected by the Parma Province Cancer Registry over the 4-year period between 2004 and 2007.

RESULTS

A total of 1458 patients with a diagnosis of stage I to III invasive breast cancer were analyzed for study purposes. At a median follow-up of 4.1 years, CNS events were observed in 1.3% and 5% of HER2-negative patients and HER2-positive patients, respectively (P < .0001). The administration of trastuzumab either as adjuvant therapy or for metastatic disease was associated with a significantly increased risk of CNS involvement at first disease recurrence and after first extracranial recurrence, respectively. According to multivariate analysis, HER2-positive status and trastuzumab treatment, high Ki-67 index, and hormone receptor negativity remained independent risk factors for the development of CNS metastasis.

CONCLUSIONS

To the authors' knowledge, this is the first population-based cancer registry study analyzing factors associated with CNS recurrence in a general population of newly diagnosed breast cancer patients with known HER2 status. The data from the current study provide evidence that patients with HER2-positive breast cancer have a significantly higher incidence of CNS metastasis after treatment with trastuzumab. Improvements in systemic control and overall survival associated with trastuzumab-based therapy may lead to an "unmasking" of CNS disease recurrence that would otherwise remain clinically silent before a patient's death.

Novel biomarkers of metastatic cancer

Once metastatic disease is documented, cure is no longer the goal and the disease is generally associated with poor outcomes, with the majority of patients dying of their disease rather than other causes. The last three decades have seen significant advances in the genomics, proteomics and molecular pathology of biomarkers in cancer, allowing for individualization of therapy that has significantly and positively impacted survival outcomes. Genetic signatures have been identified that can predict not only the future development of metastases, but also the development of specific sites of metastases. Protein biomarkers have been identified that are in use clinically for the monitoring of both disease progression and therapeutic efficacy. DNA- and RNA-based biomarkers have also been identified. This review will focus on some of the novel biomarkers that have been developed over the last decade.

Metastatic behavior of breast cancer subtypes

PURPOSE

Prognostic and predictive factors are well established in early-stage breast cancer, but less is known about which metastatic sites will be affected.

METHODS

Patients with early-stage breast cancer diagnosed between 1986 and 1992 with archival tissue were included. Subtypes were defined as luminal A, luminal B, luminal/human epidermal growth factor receptor 2 (HER2), HER2 enriched, basal-like, and triple negative (TN) nonbasal. Distant sites were classified as brain, liver, lung, bone, distant nodal, pleural/peritoneal, and other. Cumulative incidence curves were estimated for each site according to competing risks methods. Association between the site of relapse and subtype was assessed in multivariate models using logistic regression.

RESULTS

Median follow-up time among 3,726 eligible patients was 14.8 years. Median durations of survival with distant metastasis were 2.2 (luminal A), 1.6 (luminal B), 1.3 (luminal/HER2), 0.7 (HER2 enriched), and 0.5 years (basal-like; P < .001). Bone was the most common metastatic site in all subtypes except basal-like tumors. In multivariate analysis, compared with luminal A tumors, luminal/HER2 and HER2-enriched tumors were associated with a significantly higher rate of brain, liver, and lung metastases. Basal-like tumors had a higher rate of brain, lung, and distant nodal metastases but a significantly lower rate of liver and bone metastases. TN nonbasal tumors demonstrated a similar pattern but were not associated with fewer liver metastases.

CONCLUSION

Breast cancer subtypes are associated with distinct patterns of metastatic spread with notable differences in survival after relapse.

Neoadjuvant versus adjuvant chemotherapy for triple negative breast cancer

BACKGROUND

The study aim was to investigate factors that predict the use of neoadjuvant versus adjuvant chemotherapy in patients with triple negative breast cancer (TNBC) and the overall survival in each group.

METHODS

We identified 493 patients with Stage I-III TNBC between 1998 and 2008. Patients were divided according to receipt of neoadjuvant, adjuvant, or none/unknown chemotherapy. Data were compared using chi(2) and Fisher's exact test. For more than two group comparisons and analyzing multiple dependent variables, MANOVA was used. Kaplan-Meier curves were generated.

RESULTS

Of 493 patients with TNBC, 154 (31%) received neoadjuvant chemotherapy, 251 (51%) received adjuvant chemotherapy, and 88 (18%) had no or unknown chemotherapy. Patients undergoing neoadjuvant chemotherapy were younger (mean 50, range 20-83) compared with those undergoing adjuvant chemotherapy (mean 53, range 25-83) or none/unknown chemotherapy (mean 62, range 29-86) (P < 0.0001). The three groups did not differ significantly by patient race, tumor histology, or tumor grade. Increased tumor size, nodal positivity, and advanced stage were more likely to be associated with use of neoadjuvant chemotherapy (all comparisons P < 0.0001). After controlling for covariates associated with survival in unadjusted tests, patients undergoing adjuvant therapy were less likely to die compared with patients undergoing neoadjuvant therapy or none/unknown therapy (overall aHR 0.476, 95% CI 0.295-0.770).

CONCLUSIONS

Women with TNBC who underwent adjuvant chemotherapy were 52% less likely to die overall compared with those who received neoadjuvant chemotherapy or none/unknown chemotherapy in this institutional series. Prospective studies are necessary to determine if this finding is durable.

Triple-negative breast cancer--current status and future directions

Triple-negative breast cancer (TNBC) is defined by a lack of expression of both estrogen and progesterone receptor as well as human epidermal growth factor receptor 2. It is characterized by distinct molecular, histological and clinical features including a particularly unfavorable prognosis despite increased sensitivity to standard cytotoxic chemotherapy regimens. TNBC is highly though not completely concordant with various definitions of basal-like breast cancer (BLBC) defined by high-throughput gene expression analyses. The lack in complete concordance may in part be explained by both BLBC and TNBC comprising entities that in themselves are heterogeneous. Numerous efforts are currently being undertaken to improve prognosis for patients with TNBC. They comprise both optimization of choice and scheduling of common cytotoxic agents (i.e. addition of platinum salts or dose intensification strategies) and introduction of novel agents (i.e. poly-ADP-ribose-polymerase-1 inhibitors, agents targeting the epidermal growth factor receptor, multityrosine kinase inhibitors or antiangiogenic agents).