Brain metastases from breast cancer: prognostic significance of HER-2 overexpression, effect of trastuzumab and cause of death

Role of microsurgical tumor burden reduction in patients with breast cancer brain metastases considering molecular subtypes: a two-center volumetric survival analysis

BACKGROUND

Advancements in metastatic breast cancer (BC) treatment have enhanced overall survival (OS), leading to increased rates of brain metastases (BM). This study analyzes the association between microsurgical tumor reduction and OS in patients with BCBM, considering tumor molecular subtypes and perioperative treatment approaches.

METHODS

Retrospective analysis of surgically treated patients with BCBM from two tertiary brain tumor Swiss centers. The association of extent of resection (EOR), gross-total resection (GTR) achievement, and postoperative residual tumor volume (RV) with OS and intracranial progression-free survival (IC-PFS) was evaluated using Cox proportional hazard model.

RESULTS

101 patients were included in the final analysis, most patients (38%) exhibited HER2-/HR + BC molecular subtype, followed by HER2 + /HR + (25%), HER2-/HR- (21%), and HER2 + /HR- subtypes (13%). The majority received postoperative systemic treatment (75%) and radiotherapy (84%). Median OS and intracranial PFS were 22 and 8 months, respectively. The mean pre-surgery intracranial tumor volume was 26 cm3, reduced to 3 cm3 post-surgery. EOR, GTR achievement and RV were not significantly associated with OS or IC-PFS, but higher EOR and lower RV correlated with extended OS in patients without extracranial metastases. HER2-positive tumor status was associated with longer OS, extracranial metastases at BM diagnosis and symptomatic lesions with shorter OS and IC-PFS.

CONCLUSIONS

Our study found that BC molecular subtypes, extracranial disease status, and BM-related symptoms were associated with OS in surgically treated patients with BCBM. Additionally, while extensive resection to minimize residual tumor volume did not significantly affect OS across the entire cohort, it appeared beneficial for patients without extracranial metastases.

New Frontiers in the Treatment of Patients with HER2+ Cancer and Brain Metastases: Is Radiotherapy Always Useful?

Brain metastases (BM) pose a significant challenge in the management of HER2+ breast cancer since almost 50% of patients with HER2+ breast cancer develop brain tumors. The complex process of brain metastases involves genetic mutations, adaptations and mechanisms to overcome the blood-brain barrier. While radiotherapy is still fundamental in local therapy, its use is associated with cognitive adverse effects and limited long-term control, necessitating the exploration of alternative treatments. Targeted therapies, including tyrosine kinase inhibitors, monoclonal antibodies, and antibody-drug conjugates, offer promising options for HER2+ breast cancer patients with BM. Clinical trials have demonstrated the efficacy of these agents in controlling tumor growth and improving patient outcomes, posing the question of whether radiotherapy is always the unique choice in treating this cancer. Ongoing research into novel anti-HER2 antibodies and innovative combination therapies holds promise for advancing treatment outcomes and enhancing patient care in this clinical scenario. This narrative review provides a comprehensive overview of traditional medical treatments, molecularly targeted therapy and investigational agents in the management of HER2+ breast cancer with BM, highlighting the evolving landscape and potential future directions in treatment strategies to improve patient survival and quality of life.

Long-term Survival From Breast Cancer Brain Metastases in the Era of Modern Systemic Therapies

BACKGROUND AND OBJECTIVES

Median survival for all patients with breast cancer with brain metastases (BCBMs) has increased in the era of targeted therapy (TT) and with improved local control of intracranial tumors using stereotactic radiosurgery (SRS) and surgical resection. However, detailed characterization of the patients with long-term survival in the past 5 years remains sparse. The aim of this article is to characterize patients with BCBM who achieved long-term survival and identify factors associated with the uniquely better outcomes and to find predictors of mortality for patients with BCBM.

METHODS

We reviewed 190 patients with breast cancer with 931 brain tumors receiving SRS who were followed at our institution with prospective data collection between 2012 and 2022. We analyzed clinical, molecular, and imaging data to assess relationship to outcomes and tumor control.

RESULTS

The median overall survival from initial SRS and from breast cancer diagnosis was 25 months (95% CI 19-31 months) and 130 months (95% CI 100-160 months), respectively. Sixteen patients (17%) achieved long-term survival (survival ≥5 years from SRS), 9 of whom are still alive. Predictors of long-term survival included HER2+ status ( P = .041) and treatment with TT ( P = .046). A limited number of patients (11%) died of central nervous system (CNS) causes. A predictor of CNS-related death was the development of leptomeningeal disease after SRS ( P = .025), whereas predictors of non-CNS death included extracranial metastases at first SRS ( P = .017), triple-negative breast cancer ( P = .002), a Karnofsky Performance Status of <80 at first SRS ( P = .002), and active systemic disease at last follow-up ( P = .001). Only 13% of patients eventually needed whole brain radiotherapy. Among the long-term survivors, none died of CNS progression.

CONCLUSION

Patients with BCBM can achieve long-term survival. The use of TT and HER2+ disease are associated with long-term survival. The primary cause of death was extracranial disease progression, and none of the patients living ≥5 years died of CNS-related disease.

Combination of radiotherapy and targeted therapy for HER2-positive breast cancer brain metastases

Radiotherapy and targeted therapy are essential treatments for patients with brain metastases from human epidermal growth factor receptor 2 (HER2)-positive breast cancer. However, the combination of radiotherapy and targeted therapy still needs to be investigated, and neurotoxicity induced by radiotherapy for brain metastases has also become an important issue of clinical concern. It remained unclear how to achieve the balance of efficacy and toxicity with the application of new radiotherapy techniques and new targeted therapy drugs. This article reviews the benefits and potential risk of combining radiotherapy and targeted therapy for HER2-positive breast cancer with brain metastases.

Clinicopathological characteristics and prognosis of breast cancer patients with isolated central nervous system metastases in the multicentre ESME database

BACKGROUND

As a result of progress in diagnosis and treatment, there is a growing prevalence of metastatic breast cancer (MBC) with isolated CNS metastases. This study describes the largest-to-date real-life cohort of this clinical setting and compares it to other clinical presentations.

METHODS

We retrospectively analysed the French Epidemiological Strategy and Medical Economics (ESME) MBC database including patients who initiated treatment for MBC between 2008 and 2016. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Descriptive statistics and multivariate Cox model were used.

RESULTS

Of 22,266 patients, 647 (2.9%) and 929 (4.2%) patients had isolated first-site CNS metastases or combined with extra-CNS metastases, with longer OS for the group with isolated CNS metastases (16.9 versus 13.9 months, adjusted HR = 1.69 (95% CI: 1.50-1.91), p < 0.001). Among the 541 (2.4%) patients with isolated CNS metastases and no intrathecal therapy (excluding leptomeningeal metastases), HER2+ cases were preponderant over TN or HR+ /HER2- cases (41.6% versus 26.1% versus 28.5%, respectively, p < 0.01). The treatment strategy consisted of a combination of local treatment and systemic therapy (49.2%), local treatment only (35.5%) or systemic therapy only (11.4%), or symptomatic therapy only (3.9%). Median PFS was 6.1 months (95% CI: 5.7-6.8). Median OS was 20.7 months (95% CI: 17.3-24.3), reaching 37.9 months (95% CI: 25.9-47.6) in the HR+ /HER2+ subgroup. Older age, TN subtype, MBC-free interval of 6-12 months, lower performance status, and WBRT were associated with poorer survival. Patients who received systemic therapy within 3 months from MBC diagnosis had longer OS (24.1 versus 16.1 months, p = 0.031), but this was not significant on multivariate analysis [HR = 1.0 (95% CI: 0.7-1.3), p = 0.806].

CONCLUSIONS

Patients with isolated CNS metastases at MBC diagnosis represent a distinct population for which the role of systemic therapy needs to be further investigated in prospective studies.

Salvage Surgery for Local Control of Brain Metastases After Previous Stereotactic Radiosurgery: A Single-Center Series

BACKGROUND

Although overall survival (OS) has improved in patients with brain metastases (BMs), control of recurrent BMs remains a therapeutic challenge. Salvage surgery may achieve acceptable control rates in the setting of progression after previous stereotactic radiosurgery (SRS), yet it remains a question how additional adjuvant therapies may affect outcomes and how patient selection for salvage surgery may be optimized.

METHODS

Patients receiving salvage surgery for BM progression after previous SRS were retrospectively reviewed from a single center. Outcomes of interest included local tumor progression, leptomeningeal dissemination, and OS. Cox proportional hazard models and nominal logistic regression were applied to determine factors associated with outcomes of interest.

RESULTS

A total of 43 patients with 50 BMs were included. After salvage surgery, local progression was observed for 17 BMs (34%), leptomeningeal dissemination was observed in 17 patients (39.5%), and censored median OS was 17.9 months. On multivariate analysis, use of brachytherapy was associated with improved local control (hazard ratio [HR], 0.15; 95% confidence interval [CI], 0.04-0.6; P = 0.008). For patients treated with SRS ≥4.5 months before salvage surgery, both brachytherapy (HR, 0.07; 95% CI, 0.01-0.39; P = 0.002) and postoperative adjuvant SRS (HR, 0.14; 95% CI, 0.02-1.00; P = 0.05) were associated with improved local control compared with no adjuvant radiation therapy. Presence of extracranial malignancy (HR, 6.70; 95% CI, 2.58-17.42; P < 0.0001) was associated with shorter survival. Graded prognostic assessment underestimated survival in 79.1% of patients, with a mean difference of 18.9 months between graded prognostic assessment-estimated and actual OS.

CONCLUSIONS

In properly selected patients, salvage surgery may be an appropriate therapy for BM progression after previous SRS. Adjuvant brachytherapy and repeat SRS can offer significant benefit for local control with salvage resection.

Current treatment options for HER2-positive breast cancer patients with brain metastases

Brain metastases (BMs) are frequently associated with HER2+ breast cancer (BC). Their management is based on a multi-modal strategy including both local treatment and systemic therapy. Despite therapeutic advance, BMs still have an adverse impact on survival and quality of life and the development of effective systemic therapy to prevent and treat BMs from HER2 + BC represents an unmet clinical need. Trastuzumab-based therapy has long been the mainstay of systemic therapy and over the last two decades other HER2-targeted agents including lapatinib, pertuzumab and trastuzumab emtansine, have been introduced in the clinical practice. More recently, novel agents such as neratinib, tucatinib and trastuzumab deruxtecan have been developed, with interesting activity against BMs. Further research is needed to better elucidate the best sequence of these agents and their combination with local treatment.

The Management of Brain Metastases-Systematic Review of Neurosurgical Aspects

The multidisciplinary management of patients with brain metastases (BM) consists of surgical resection, different radiation treatment modalities, cytotoxic chemotherapy, and targeted molecular treatment. This review presents the current state of neurosurgical technology applied to achieve maximal resection with minimal morbidity as a treatment paradigm in patients with BM. In addition, we discuss the contribution of neurosurgical resection on functional outcome, advanced systemic treatment strategies, and enhanced understanding of the tumor biology.

HER2-targeted therapy prolongs survival in patients with HER2-positive breast cancer and intracranial metastatic disease: a systematic review and meta-analysis

BACKGROUND

Intracranial metastatic disease (IMD) is a serious and known complication of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The role of targeted therapy for patients with HER2-positive breast cancer and IMD remains unclear. In this study, we sought to evaluate the effect of HER2-targeted therapy on IMD from HER2-positive breast cancer.

METHODS

We searched MEDLINE, EMBASE, CENTRAL, and gray literature sources for interventional and observational studies reporting survival, response, and safety outcomes for patients with IMD receiving HER2-targeted therapy. We pooled outcomes through meta-analysis and examined confounder effects through forest plot stratification and meta-regression. Evidence quality was evaluated using GRADE (PROSPERO CRD42020161209).

RESULTS

A total of 97 studies (37 interventional and 60 observational) were included. HER2-targeted therapy was associated with prolonged overall survival (hazard ratio [HR] 0.47; 95% confidence interval [CI], 0.39-0.56) without significantly prolonged progression-free survival (HR 0.52; 95% CI, 0.27-1.02) versus non-targeted therapy; the intracranial objective response rate was 19% (95% CI, 12-27%), intracranial disease control rate 62% (95% CI, 55-69%), intracranial complete response rate 0% (95% CI, 0-0.01%), and grade 3+ adverse event rate 26% (95% CI, 11-45%). Risk of bias was high in 40% (39/97) of studies.

CONCLUSION

These findings support a potential role for systemic HER2-targeted therapy in the treatment of patients with IMD from HER2-positive metastatic breast cancer.

Phase I Study of Intermittent High-Dose Lapatinib Alternating with Capecitabine for HER2-Positive Breast Cancer Patients with Central Nervous System Metastases

PURPOSE

Lapatinib and capecitabine cross the blood-tumor barrier in breast cancer brain metastasis but have modest clinical efficacy. Administration of high-dose tyrosine kinase inhibitor has been evaluated in brain metastases and primary brain tumors as a strategy to improve drug exposure in the central nervous system (CNS). We derived a rational drug scheduling of intermittent high-dose lapatinib alternating with capecitabine based on our preclinical data and Norton-Simon mathematical modeling. We tested this intermittent, sequential drug schedule in patients with breast cancer with CNS metastasis.

PATIENTS AND METHODS

We conducted a phase I trial using an accelerated dose escalation design in patients with HER2-positive (HER2+) breast cancer with CNS metastasis. Lapatinib was given on day 1-3 and day 15-17 with capecitabine on day 8-14 and day 22-28 on an every 28-day cycle. Lapatinib dose was escalated, and capecitabine given as a flat dose at 1,500 mg BID. Toxicity and efficacy were evaluated.

RESULTS

Eleven patients were enrolled: brain only (4 patients, 36%), leptomeningeal (5 patients, 45%), and intramedullary spinal cord (2 patients, 18%). Grade 3 nausea and vomiting were dose-limiting toxicities. The MTD of lapatinib was 1,500 mg BID. Three patients remained on therapy for greater than 6 months.

CONCLUSIONS

High-dose lapatinib is tolerable when given intermittently and sequentially with capecitabine. Antitumor activity was noted in both CNS and non-CNS sites of disease. This novel administration regimen is feasible and efficacious in patients with HER2+ breast cancer with CNS metastasis and warrants further investigation.

Prognostic Value of Brain Metastasis-Free Interval in Patients with Breast Cancer Brain Metastases

BACKGROUND

In patients with breast cancer brain metastases (BCBM), time between primary tumor diagnosis and appearance of brain metastases varies widely. Despite being a readily available clinical parameter, it remains unclear whether brain metastasis-free interval (BMFI) carries prognostic value among breast cancer patients. The aim of this study was to compare characteristics and overall survival among patients with varying BMFIs and to assess the prognostic role, if any, for BMFI.

METHODS

We retrospectively reviewed 3 institutional databases of adult female patients who were treated for BCBM between 1996 and 2017. Cox proportional hazards model and Kaplan-Meier survival curves were used to determine prognostic value of BMFI for survival.

RESULTS

A total of 503 patients were included. Median age at first brain metastasis was 52 (interquartile range [IQR]: 45-58) years. Median BMFI was 38 months (IQR: 18-66), and median overall survival was 17 months (IQR: 8-31). In univariate Cox proportional hazards model, younger age at BCBM, estrogen receptor (ER)+/human epidermal growth factor receptor 2 (HER2)+ tumor subtype, and the absence of liver or lung metastases were associated with longer survival. BMFI >3 years was not associated with longer survival (hazard ratio [HR] = 1.13; P = 0.21). In multivariate analysis, only subtype (ER+/HER2+ vs. ER-/HER2-; HR = 0.77; P = 0.02) and liver metastases (HR = 1.36; P = 0.01) were prognostic for survival. There was no significant association between BMFI and overall survival (HR = 0.99; P = 0.91).

CONCLUSIONS

In this large, retrospective cohort of breast cancer patients, BMFI was not prognostic for overall survival.

Targeting Molecular Pathways in Intracranial Metastatic Disease

The discovery and clinical application of agents targeting pivotal molecular pathways in malignancies such as lung, breast, renal cell carcinoma, and melanoma have led to impressive improvements in clinical outcomes. Mutations in epidermal growth factor receptor (EGFR), and rearrangements of anaplastic lymphoma kinase (ALK) are targetable in lung cancer, while BRAF mutations have been successfully targeted in metastatic melanoma. Targeting estrogen receptors, cyclin dependent kinases, and HER2 (Human Epidermal Receptor) have resulted in improvement in survival in breast cancer. Major strides have been made in the management of metastatic renal cell carcinoma by targeting the vascular endothelial growth factor (VEGF) pathway. However, intracranial metastases remain a major hurdle in the setting of targeted therapies. Traditional treatment options for brain metastases include surgery, whole brain radiation therapy (WBRT), and stereotactic radiosurgery (SRS). Surgery is effective in symptomatic patients with dominant lesions or solitary intracranial metastases, however, recovery time can be prolonged, often requiring an interruption in systemic treatment. WBRT and SRS provide symptomatic relief and local control but data on improving overall survival is limited. Most targeted therapies which provide extracranial control have limited penetration through the blood brain barrier. Given the limited therapeutic options and increasing prevalence of brain metastases, finding new strategies for the management of intracranial metastatic disease is critical. Genomic analysis of brain metastases has led to a better understanding of variations in the driver mutations compared to the primary malignancy. Furthermore, newer generations of targeted agents have shown promising intracranial activity. In this review, we will discuss the major molecular alterations in brain metastases from melanoma, lung, breast, and renal cell carcinoma. We will provide an in-depth review of the completed and ongoing clinical trials of drugs targeting the molecular pathways enriched in brain metastases.

Analysis of survival outcomes based on molecular subtypes in breast cancer brain metastases: A single institutional cohort

PURPOSE

To evaluate the survival outcomes based on molecular subtypes of breast cancer in patients with brain metastasis.

MATERIALS AND METHODS

We retrospectively reviewed 106 breast cancer patients treated for brain metastases, from January 2005 to May 2016. Patients were divided into four groups based on the tumor molecular subtype: luminal A (Estrogen Receptor [ER]/Progesterone Receptor [PR] positive, human epithelial growth factor receptor-2 [HER2] negative), luminal B (ER/PR positive, HER2 Positive), HER2 (HER2 positive and ER/PR negative), and Triple negative (TNBC).

RESULTS

The median follow-up time for surviving patients was 22 months (range: 11.2-51.1 months). The median survival of all patients was 14 months, with a 1-year overall survival (OS) rate of 57.5% and a 2-year OS rate of 32.1%. Thirty patients (28.3%) had a solitary brain metastasis while 62 (58.5%) patients had multiple metastases. A significant difference was observed in the survival rates of the two groups. Based on the Karnofsky performance score, the performance status of the patients at the time of brain metastasis was also found to affect survival. Patients with different molecular subtypes had different survival rates; the luminal A group showed the highest median survival (luminal A: 23.1, luminal B: 15.0, HER2: 12.5 and TNBC: 6.4 months, respectively), which was statistically significant.

CONCLUSION

In breast cancer patients with brain metastasis, survival rates were different based on the molecular subtype of the tumor, despite various local and systemic treatments. Appropriate and tailored treatment approaches should, therefore, be considered for the different molecular subtypes.

Genetic heterogeneity and actionable mutations in HER2-positive primary breast cancers and their brain metastases

Brain metastases constitute a challenge in the management of patients with HER2-positive breast cancer treated with anti-HER2 systemic therapies. Here we sought to define the repertoire of mutations private to or enriched for in HER2-positive brain metastases. Massively parallel sequencing targeting all exons of 254 genes frequently mutated in breast cancers and/or related to DNA repair was used to characterize the spatial and temporal heterogeneity of HER2-positive breast cancers and their brain metastases in six patients. Data were analyzed with state-of-the-art bioinformatics algorithms and selected mutations were validated with orthogonal methods. Spatial and temporal inter-lesion genetic heterogeneity was observed in the HER2-positive brain metastases from an index patient subjected to a rapid autopsy. Genetic alterations restricted to the brain metastases included mutations in cancer genes FGFR2, PIK3CA and ATR, homozygous deletion in CDKN2A and amplification in KRAS. Shifts in clonal composition and the acquisition of additional mutations in the progression from primary HER2-positive breast cancer to brain metastases following anti-HER2 therapy were investigated in additional five patients. Likely pathogenic mutations private to or enriched in the brain lesions affected cancer and clinically actionable genes, including ATR, BRAF, FGFR2, MAP2K4, PIK3CA, RAF1 and TP53. Changes in clonal composition and the acquisition of additional mutations in brain metastases may affect potentially actionable genes in HER2-positive breast cancers. Our observations have potential clinical implications, given that treatment decisions for patients with brain metastatic disease are still mainly based on biomarkers assessed in the primary tumor.

Development of CNS metastases and survival in patients with inflammatory breast cancer

BACKGROUND

Inflammatory breast cancer (IBC) is associated with a poor prognosis and high risk of central nervous system (CNS) metastases.

METHODS

We retrospectively reviewed stage III-IBC patients compared with noninflammatory invasive ductal carcinoma (NI-IDC) patients treated between January 1, 1984, and December 31, 2011, who began primary treatment within 1 year of diagnosis and had been followed up for at least 1 year before the development of CNS metastasis or death. Cumulative CNS metastasis incidence and post-CNS metastasis overall survival (OS) estimates were computed. Multivariable Cox proportional hazard models explored factors for post-CNS metastasis survival.

RESULTS

A total of 2323 patients were identified (589-IBC/1734-NI-IDC). Eighty-one IBC patients developed CNS metastasis, versus 154 NI-IDC patients. The 2-, 5-, and 10-year cumulative CNS metastasis incidence rates in IBC and NI-IDC were 9.8%, 15.8%, 17.4% and 6.5%, 10.1%, and 12.7%, respectively. This was significantly different between IBC and NI-IDC patients (P = .0037). Multicovariate competing risk regression models in IBC and NI-IDC patients showed no statistically significant associations with the risk of developing CNS metastasis, except neoadjuvant taxane use in NI-IDC patients (hazard ratio, 0.45; 95% confidence interval, 0.24-0.83; P = .011). The median follow-up was 7.2 years, and the median post-CNS metastasis OS was not significantly different between IBC (7.6 months) and NI-IDC (5.6 months) patients. One hundred ninety patients with CNS metastasis died. HER2-positive patients had better OS, with a median 14.1 versus 4.3 months (P < .0001). Age >50 years (P = .012) but not IBC status was a significant predictor of post-CNS metastasis survival.

CONCLUSION

IBC patients demonstrated higher CNS metastasis incidence rates but OS following CNS metastases is similar in both groups. HER2 status and age may play prognostic roles. Cancer 2018;124:2299-305. © 2018 American Cancer Society.

A nomogram for predicting survival in patients with breast cancer brain metastasis

Brain metastasis (BM) is common in patients with breast cancer. Predicting patient survival is critical for the clinical management of breast cancer brain metastasis (BCBM). The present study was designed to develop and evaluate a prognostic model for patients with newly diagnosed BCBM. Based on the clinical data of patients with BCBM treated in the Affiliated Hospital of Academy of Military Medical Sciences (Beijing, China) between 2002 and 2014, a nomogram was developed to predict survival using proportional hazards regression analysis. The model was validated internally by bootstrapping, and the concordance index (c-index) was calculated. A calibration curve and c-index were used to evaluate discriminatory and predictive ability, in order to compare the nomogram with widely used models, including recursive partitioning analysis (RPA), graded prognostic assessment (GPA) and breast-graded prognostic assessment (Breast-GPA). A total of 411 patients with BCBM were included in the development of this predictive model. The median overall survival time was 14.1 months. Statistically significant predictors for patient survival included biological subtype, Karnofsky performance score, leptomeningeal metastasis, extracranial metastasis, the number of brain metastases and disease-free survival. A nomogram for predicting 1- and 2-year overall survival rates was constructed, which exhibited good accuracy in predicting overall survival with a concordance index of 0.735. This model outperformed RPA, GPA and Breast-GPA, based on the comparisons of the c-indexes. The nomogram constructed based on a multiple factor analysis was able to more accurately predict the individual survival probability of patients with BCBM, compared with existing models.

Brain metastasis in gastroesophageal adenocarcinoma and HER2 status

The increased survival of patients with gastroesophageal adenocarcinoma (GAD) following improvements in treatment has been accompanied by a rising incidence of secondary brain metastasis. HER2 amplification/overexpression, which has been associated with an increased risk of brain metastasis in breast cancer, is found in about 20% of patients with GAD. The aim of this study was to evaluate the effect of HER2 status on brain metastasis in GAD. The database of a tertiary cancer center was searched for patients with GAD diagnosed in 2011-2015, and data were collected on clinical characteristics, brain metastasis, HER2 status, and outcome. We identified 404 patients with a confirmed diagnosis of GAD. HER2 results were available for 298: 69 (23.2%) positive and 227 negative. Brain metastasis developed in 15 patients with GAD (3.7%); HER2 results, available in 13, were positive in 6, negative in 6, and equivocal in 1. The brain metastasis rate was significantly higher in HER2-positive than HER2-negative patients with GAD (6/69, 8.7% vs. 6/227, 2.6%; RR = 3.3, 95% CI 1.1-9.9, p = 0.034). Median overall survival from diagnosis of brain metastasis was 2.3 months, with no significant difference by HER2 status. HER2 positive GAD patients may be at increased risk to develop BM. Clinicians should maintain a lower threshold for performing brain imaging in patients with HER2-positive GAD given their increased risk of brain metastasis. The role of anti-HER2 agents in the development and treatment of brain metastasis in GAD warrants further study.

Systemic therapy for brain metastases

Central nervous system metastases cause grave morbidity in patients with advanced malignancies. Lung cancer, breast cancer, and melanoma are the three most common causes of brain metastases. Although the exact incidence of brain metastases is unclear, there appears to be an increasing incidence which has been attributed to longer survival, better control of systemic disease, and better imaging modalities. Until recently surgical resection of solitary or symptomatic brain metastases, and radiation therapy (either whole-brain radiation therapy or stereotactic radiation) were the mainstay of treatment for patients with brain metastases. The majority of traditional chemotherapies have shown limited activity in the central nervous system, which has been attributed to the blood-brain barrier and the molecular structure of the used agents. The discovery of driver mutations and drugs targeting these mutations has changed the treatment landscape. Several of these targeted small-molecule tyrosine kinase inhibitors do cross the blood-brain barrier and/or have shown activity in the central nervous system. Another major advance in the care of brain metastases has been the advent of new immunotherapeutic agents, for which initial studies have shown intracranial activity. In this chapter, we will review the unique challenges in the treatment of brain metastases. The pertinent clinical studies of chemotherapy in brain metastases will be discussed. The currently reported clinical trials and evidence for use of targeted therapies and immunotherapeutic agents will be emphasized.

Biological subtypes and survival outcomes in breast cancer patients with brain metastases in the targeted therapy era

Background

There is recognition that breast cancer is a collection of heterogeneous diseases divided in subtypes based on combined molecular features such as hormonal receptors (HR) and human epidermal growth factor receptor 2 (HER2) status. We aimed to study clinical differences among biological subtypes in brain metastasis from breast cancer after targeted therapy introduction.

Methods

This was a retrospective study with 406 consecutive patients with brain metastasis from breast cancer treated at MD Anderson Cancer Center from 1998 to 2013. Overall, 315 of these patients met the study criteria and were analyzed. Subtypes were classified as HER2-/HR+ (96 patients), HER2+/HR+ (57 patients), HER2+/HR- (63 patients), and triple negative (HER2-/HR-) (99 patients). End points were time to development of brain metastasis (TDBM), brain metastasis-free survival (BMFS), and overall survival from start of treatment of brain metastasis (OSBM). Univariate and multivariate Cox proportional hazard regression models were used to analyze the data.

Results

TDBM was 41 months for HER2-/HR+; 58 months for HER2+/HR+; 30 months for HER2+/HR-; and 27 months for triple negative (P < .001). BMFS was 9 months for HER2-/HR+; 24 months for HER2+/HR+; 9 months for HER2+/HR-; and 7 months for triple negative (P = .06). OSBM was 20 months for HER2-/HR+; 22 months for HER2+/HR+; 24 months for HER2+/HR-; and 9 months for triple negative (P < .001). On multivariate analyses, triple negative showed lower OSBM compared with other subtypes, with a hazard ratio of 1.9 (P < .001).

Conclusion

Comparing all breast cancer subgroups we noticed that HR and HER2 are the most significant biomarkers in brain metastasis behavior. Patients who received targeted therapy had better outcomes, but not in the triple negative group. Prospective studies with different treatment modalities for each subgroup are recommended.

Characteristics and Prognostic Factors for Patients With HER2-overexpressing Breast Cancer and Brain Metastases in the Era of HER2-targeted Therapy: An Argument for Earlier Detection

BACKGROUND

Although brain metastases (BM) are associated with poor prognosis, patients with human epidermal growth factor receptor 2 (HER2) overexpressing (HER2⁺) breast cancer (BC) with BM who are treated with anti-HER2 therapy have a relatively longer survival after BM diagnosis compared with other subtypes and HER2⁺ patients previously untreated with anti-HER2 therapy. It is unclear if previously reported prognostic factors are applicable to patients with HER2⁺ BC in the era of HER2-targeted therapy.

PATIENTS AND METHODS

We evaluated 100 consecutive patients with HER2⁺ BC with BM who underwent radiation therapy as primary BM treatment from January 2001 to December 2011 at Memorial Sloan Kettering Cancer Center by retrospective review. Patient characteristics at the time of BM diagnosis and their associations with time from BM to death were evaluated by Kaplan-Meier curves, log-rank tests, and Cox proportional hazard models.

RESULTS

Significantly better survival from BM was noted for patients with higher performance status, fewer BM lesions, continued use of HER2-targeted therapy after BM diagnosis, and better controlled extracranial metastatic disease. Absence of neurologic symptoms at BM diagnosis was significantly associated with fewer lesions, decreased use of whole brain radiotherapy, and longer survival in univariate and multivariate analysis (multivariate hazard ratio, 3.69; 95% confidence interval, 1.69-8.07).

CONCLUSION

Our finding supports the continued use of HER2-targeted therapy after BM diagnosis. In addition, future research on the clinical impact of detecting asymptomatic BM in patients with HER2⁺ BC, in terms of improving prognosis, quality of life, and avoidance of whole brain radiotherapy, is warranted.

The efficacy of lapatinib and capecitabine in HER-2 positive breast cancer with brain metastases: A systematic review and pooled analysis

INTRODUCTION

Breast cancer (BC) with HER-2/neu overexpression or amplification (HER-2+) is associated with a higher prevalence of brain metastases (BMs) when compared to other subtypes. Among approved drugs for HER-2+ BC, lapatinib (L) is associated with single agent activity toward BMs. We conducted a systematic review to determine the efficacy of L, singly or in combination with capecitabine (C), as a treatment for HER-2+ BMs.

MATERIAL AND METHODS

We searched PubMed, EMBASE, The Cochrane Library, SCOPUS, Web of Science, ClinicalTrials.gov, World Health Organization International Clinical Trials Registry Platform (ICTRP), and the European Union Clinical Trials Register for studies reporting data on L, singly or in combination with C, for the treatment of HER-2+ BC with BMs. Primary end-points were overall response rate (ORR) and disease control rate (DCR); these were pooled to provide an aggregate value. Progression-free survival (PFS) and overall survival (OS) were secondary end-points. Data were pooled using number of events/number of evaluable patients, according to a fixed or random effect model.

RESULTS

Overall, 12 studies were included in the present meta-analysis, for a total of 799 patients with BMs. The pooled overall response rate (ORR) was 21.4% (95% CI 11.7-35.9). After exclusion of patients that received L alone, ORR reached 29.2% (95% CI 18.5-42.7). The pooled median PFS and OS were 4.1 (95% CI 3.1-6.7) and 11.2 (95% CI 8.9-14.1) months, respectively.

CONCLUSIONS

Due to its activity on BMs, the L + C combination may be considered for HER-2+ BC that has progressed in the brain, when local therapy has been performed or failed and re-irradiation is not feasible.

Targeted Therapies for Brain Metastases from Breast Cancer

The discovery of various driver pathways and targeted small molecule agents/antibodies have revolutionized the management of metastatic breast cancer. Currently, the major targets of clinical utility in breast cancer include the human epidermal growth factor receptor 2 (HER2) and epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF) receptor, mechanistic target of rapamycin (mTOR) pathway, and the cyclin-dependent kinase 4/6 (CDK-4/6) pathway. Brain metastasis, however, remains a thorn in the flesh, leading to morbidity, neuro-cognitive decline, and interruptions in the management of systemic disease. Approximately 20%–30% of patients with metastatic breast cancer develop brain metastases. Surgery, whole brain radiation therapy, and stereotactic radiosurgery are the traditional treatment options for patients with brain metastases. The therapeutic paradigm is changing due to better understanding of the blood brain barrier and the advent of tyrosine kinase inhibitors and monoclonal antibodies. Several of these agents are in clinical practice and several others are in early stage clinical trials. In this article, we will review the common targetable pathways in the management of breast cancer patients with brain metastases, and the current state of the clinical development of drugs against these pathways.

Central nervous system involvement in breast cancer patients: Is the therapeutic landscape changing too slowly?

Central nervous system (CNS) involvement from breast cancer (BC) has been historically considered a relatively rare event. However, the development of new therapeutic strategies with a better control of extra-cranial disease and a longer overall survival (OS) has determined an increased incidence of brain metastases. Patients with HER2-positive or triple negative BC have higher occurrence of CNS involvement than patients with luminal-like disease. Moreover, after development of brain metastases, the prognosis is highly influenced by biological subtype. In patients with multiple brain metastases who experience important neurological symptoms, palliative treatment, with or without whole brain radiation therapy (WBRT), needs to be considered the first step of a multidisciplinary therapeutic approach. Patients with a good performance status and 1-3 brain lesions should be considered for radical surgery; patients technically inoperable with 4-5 metastases smaller than 3cm may undergo stereotactic radiosurgery. The role of systemic therapy in the management of patients with brain metastases is controversial. Preliminary data suggest that systemic therapy after WBRT may improve survival in BC patients with brain lesions. In patients with HER2-positive disease, several retrospective or post hoc analyses showed a longer brain progression-free survival with trastuzumab in combination with or followed by other anti-HER2 drugs (such as pertuzumab, lapatinib, and T-DM1). Until now, no new strategies or drugs are available for triple-negative and luminal-like BC.

Radiotherapy of brain metastases from breast cancer: Treatment results and prognostic factors

Brain metastases (BM) from breast cancer are associated with high morbidity and a poor prognosis. The aim of this study was to analyse the role of radiotherapy in treatment of BM from breast cancer in the context of modern local therapy modalities, current systemic treatment options and prognostic factors. A retrospective analysis of 86 consecutive female patients treated with radiotherapy for BM from breast cancer between 2000 and 2010 was conducted. Patient and treatment characteristics were registered and survival data calculated. All patients received whole-brain radiotherapy (WBRT) with a median dose of 36 Gy, and 19 patients were treated with an additional boost; this included fractionated schemes (median dose, 18 Gy) and radiosurgery (5 and 17 Gy). The median overall survival time from the start of WBRT was 4.1 months in the present cohort. Patients receiving a boost survived 19.7 months in comparison to 3.1 months for patients treated with WBRT alone (P<0.001). Other factors that improved overall survival, based on a univariate analysis, were dose of WBRT and number of BM. There was no statistical evidence for the influence of the human epidermal growth factor receptor 2 status on survival in the current study. The administration of boost treatment following WBRT was also identified as a significant factor influencing survival on multivariate analysis (P=0.030). In conclusion, radiotherapy affects the survival time of patients with BM from breast cancer. In particular, the implementation of boost treatment following WBRT in selected patients seems to extend survival time.

The Rationale for Targeted Therapies and Stereotactic Radiosurgery in the Treatment of Brain Metastases

Brain metastases are the most common intracranial malignancy. Many approaches, including radiation therapy, surgery, and cytotoxic chemotherapy, have been used to treat patients with brain metastases depending on the patient's disease burden and symptoms. However, stereotactic surgery (SRS) has revolutionized local treatment of brain metastases. Likewise, targeted therapies, including small-molecule inhibitors and monoclonal antibodies that target cancer cell metabolism or angiogenesis, have transformed managing systemic disease. Prospective data on combining these treatments for synergistic effect are limited, but early data show favorable safety and efficacy profiles. The combination of SRS and targeted therapy will further individualize treatment, potentially obviating the need for cytotoxic chemotherapy or whole-brain radiation. There is a great need to pursue research into these exciting modalities and novel combinations to further improve the treatment of patients with brain metastases. This article discusses reported and ongoing clinical trials assessing the safety and efficacy of targeted therapy during SRS.

IMPLICATIONS FOR PRACTICE

Treatment of patients with brain metastases requires a multidisciplinary approach. Stereotactic radiosurgery is increasingly used in the upfront setting to treat new brain metastasis. Targeted therapies have revolutionized systemic treatment of many malignancies and may sometimes be used as initial treatment in metastatic patients. There is sparse literature regarding safety and efficacy of combining these two treatment modalities. This article summarizes the supporting literature and highlights ongoing clinical trials in combining radiosurgery with targeted therapy.

Survival benefit of anti-HER2 therapy after whole-brain radiotherapy in HER2-positive breast cancer patients with brain metastasis

AIM

We aimed to assess the survival benefit of epidermal growth factor receptor 2 (HER2)-positive breast cancer patients with brain metastasis (BM) after whole-brain radiotherapy (WBRT) in combination with systemic treatments, especially anti-HER2 therapy.

METHODS

This retrospective study analyzed the overall survival (OS) of 60 HER2-positive breast cancer patients with BM after WBRT in combination with systemic treatments. Among them, 42 patients received chemotherapy while 18 patients did not receive after WBRT. With regard to anti-HER2 therapy, after WBRT, 17 patients received anti-HER2 treatment without prior adjuvant trastuzumab-based therapy, 7 patients received anti-HER2 treatment with prior adjuvant trastuzumab-based therapy, and 36 patients did not receive further anti-HER2 treatment. All patients were followed up regularly until January 23, 2013.

RESULTS

The median OS of patients with BM was 12 months. Patients who received anti-HER2 therapy and chemotherapy after WBRT had significantly better survival compared with patients who did not receive further treatment. Patients who received anti-HER2 treatment after WBRT but did not receive adjuvant trastuzumab-based therapy for early breast cancer had better OS, followed by patients who received anti-HER2 agent both in adjuvant treatment and after WBRT and patients who did not receive anti-HER2 treatment. Multivariate analysis showed that Karnofsky Performance Status, control of extracranial metastases, chemotherapy after WBRT, and anti-HER2 therapy combined with WBRT were all independent predictors for OS.

CONCLUSION

Both chemotherapy and anti-HER2 therapy after WBRT could improve OS. Moreover, patients without prior exposure to adjuvant anti-HER2 treatment may have survival benefit superior to those of patients with prior exposure.

Systemic treatment of HER2+ metastatic breast cancer: clinical conundrums and future perspectives

Improvements in the treatment of metastatic HER2-positive breast cancer constitute one of the great advances in breast cancer medicine of the last generation. From being a highly aggressive fatal condition, the use of anti-HER2-targeted therapies, in particular trastuzumab, has led to significant improvements in disease outcomes. There are reports of increasing numbers of patients alive and well more than 5 years from diagnosis of metastatic disease. Nevertheless, there remain many complex and clinically difficult scenarios where there is little in the way of randomized evidence or published guidelines to guide decision making. As a companion piece to our review of HER2-targeted therapies in the metastatic setting, we decided to focus on a series of clinical scenarios that fell outside of the standard trial-based settings and where opinions and guidance from experienced clinicians and experts in the field would be considered useful to help develop safe and effective treatment strategies. The following eight cases were put forward by our panel of experts, voted on by their peers to select the most relevant and interesting cases, and the discussions worked on by teams of two followed by review and commentary by another team of two.

Extended trastuzumab therapy improves the survival of HER2-positive breast cancer patients following surgery and radiotherapy for brain metastases

Brain metastases usually present late during the course of breast cancer and are associated with an unfavorable prognosis. It was previously demonstrated that the status of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor type 2 (HER2) may be altered in the time window between the emergence of the primary breast tumor and the development of metastases. The aim of this study was to compare the expression of ER, PR and HER2 in pathology samples of primary breast cancer and brain metastases in order to evaluate whether previously administered therapy was able to modify this status and determine whether biomarker alterations affect prognosis after the development of brain metastases. Data were collected from 62 patients who were initially diagnosed with breast cancer that had metastasized to the brain. The ER, PR and HER2 status of the samples from the primary tumors and the brain metastases was determined. Differences in the immunohistochemical profiles of ER, PR or HER2 between the primary tumors and the brain metastases in 17 patients (29.3%) were identified. The patients with HER2-positive brain metastases who received trastuzumab had no leptomeningeal metastases and exhibited a longer survival time after brain metastases compared to the HER2-positive patients who did not receive trastuzumab and the patients with HER2-negative brain metastases (P=0.0005). Our results suggested that the patients treated with trastuzumab following surgery and radiotherapy for brain metastases exhibited a better prognosis. Thus, the HER2 status in brain metastases requires re-evaluation and extended trastuzumab therapy is recommended after brain metastases.

Risk factors and survival outcomes in patients with brain metastases from breast cancer

Development of central nervous system (CNS) metastases in breast cancer (BC) is associated with poor prognosis. The incidence of CNS metastases in metastatic BC is reported to be about 10-16 %, but different subtypes of BC are associated with different risk of developing CNS metastases. We retrospectively analysed the risk of CNS metastases and the outcome in a cohort of 473 patients with metastatic BC. CNS metastases were diagnosed in 15.6 % of patients and median survival from diagnosis of CNS metastases was 7.53 (25th-75th 2.8-18.9) months. The risk of developing CNS metastases was higher in patients with grade 3, hormone receptor negative, HER2-positive, high Ki-67 BC. When compared to luminal A subtype, only HER2-positive BC was associated with increased risk of CNS metastases. Survival from diagnosis of CNS metastases was longer in patients with HER2-positive BC, while it was shorter in patients that did not receive any locoregional treatment, or with extra-CNS disease, or with more than 3 CNS lesions.

Progress in the biological understanding and management of breast cancer-associated central nervous system metastases

Metastasis to the central nervous system (CNS) is a devastating neurological complication of systemic cancer. Brain metastases from breast cancer have been documented to occur in approximately 10%-16% of cases over the natural course of the disease with leptomeningeal metastases occurring in approximately 2%-5% of cases of breast cancer. CNS metastases among women with breast cancer tend to occur among those who are younger, have larger tumors, and have a more aggressive histological subtype such as the triple negative and HER2-positive subtypes. Treatment of CNS metastases involves various combinations of whole brain radiation therapy, surgery, stereotactic radiosurgery, and chemotherapy. We will discuss the progress made in the treatment and prevention of breast cancer-associated CNS metastases and will delve into the biological underpinnings of CNS metastases including evaluating the role of breast tumor subtype on the incidence, natural history, prognostic outcome, and impact of therapeutic efficacy.

Targeted therapy in brain metastasis

PURPOSE OF REVIEW

To review the state of the art and new developments in the field of targeted agents for brain metastases.

RECENT FINDINGS

The huge amount of information on new molecular compounds and the advances in understanding the molecular pathways that mediate brain colonization have led to an increase of interest in preclinical and clinical investigations in the field of brain metastases. Targeted therapies can be employed either on established brain metastases or in a prevention setting. Targeting angiogenesis is an attractive approach. Up to date, large clinical trial datasets have shown that antiangiogenic agents do not increase the risk of bleeding into the brain. Bevacizumab (an anti-VEGF agent) is undergoing investigation in clinical trials on brain metastases from non-small cell lung cancer (NSCLC), breast cancer and melanoma. Sunitinib, a multitarget small molecule tyrosine kinase inhibitor (TKI), is a promising agent in brain metastases from renal cell cancer. The EGFR inhibitors gefitinib and erlotinib have a definite activity in brain metastases from NSCLC with activating EGFR mutations. Regarding HER2-positive breast cancer patients with established brain metastases, lapatinib (small molecule TKI) seems particularly active in association with capecitabine. Lapatinib alone is attractive in the prevention setting. Brain metastases from melanoma with BRAF V600E mutations respond to a specific inhibitor, such as vemurafenib. The immunomodulator ipilimumab is also active on brain metastases from melanoma.

SUMMARY

The use of targeted agents in brain metastases from solid tumors is promising. The setting of prevention will be probably expanded in the next years. Well designed clinical trials with proper endpoints are needed.

[The role of whole brain radiation therapy for brain metastases]

Brain metastases are the leading cause of intracranial malignancy and a major cause of mortality and morbidity. From 20 to 40% of cancer patients develop brain metastases. The irradiation of the whole brain remains the most commonly undertaken treatment, but should be discussed in relation to other therapeutic alternatives such as stereotactic radiotherapy or the use of new chemotherapy drugs. Its use according to pathology should be discussed. It can lead to a long-term neurocognitive toxicity that should be evaluated more precisely. This literature review aims to highlight the role of whole-brain radiotherapy used alone or in combination with other treatments.

The effect of tumor subtype on the time from primary diagnosis to development of brain metastases and survival in patients with breast cancer

Our group has previously published the Diagnosis-Specific Graded Prognostic Assessment (GPA) showing the prognostic factors associated with survival in patients with brain metastases (BM). The purpose of this study is to investigate the relationship of breast cancer subtype to the time interval from primary diagnosis (PD) to development of BM (TPDBM), number of BM at initial BM presentation and survival. We analyzed our previously described multi-institutional retrospective database of 865 breast cancer patients treated for newly-diagnosed BM from 1993 to 2010. Several factors found to be associated with survival were incorporated into the Breast-GPA, including tumor subtype. The GPA database was further analyzed to determine if the subtype correlated with the TPDBM, number of BM, and survival from PD. After exclusions for incomplete data, 383 patients remained eligible for analysis. The subtypes were approximated as follows: Luminal B: triple positive; HER2: HER2 positive/ER/PR negative; Luminal A; ER/PR positive/HER2 negative; Basal: triple negative. Patients with Basal (90), HER2 (119), Luminal B (98) and Luminal A (76) tumor subtypes had a median TPDBM of 27.5, 35.8, 47.4 and 54.4 months (p < 0.01), median survival from PD of 39.6, 66.4, 90.3 and 72.7 months (p < 0.01) and median survival from BM of 7.3, 17.9, 22.9 and 10.0 months (p < 0.01), respectively. Tumor subtype is an important prognostic factor for survival in patients with breast cancer and BM. Although TPDBM is not an independent prognostic factor for survival (and thus not part of the Breast-GPA), the TPDBM does correlate with tumor subtype but does not correlate with the number of BM. Patients with Basal and HER2 tumor subtypes have short TPDBM. Prospective studies are needed to determine if screening brain MRIs are indicated in patients with Basal or HER2 subtypes.

A systematic review of trastuzumab and lapatinib in the treatment of women with brain metastases from HER2-positive breast cancer

Patients with HER2-positive breast cancer are living still longer and increasingly experiencing brain metastases. Current HER2-targeted therapies have limited potential to cross the blood-brain-barrier. We performed a systematic review to investigate data on HER2-targeting therapies in the treatment of brain metastases in breast cancer. We searched PUBMED for all human studies published 1998-2012 using the following search terms: breast neoplasm/cancer, human epidermal growth factor receptor 2/HER2, ErbB2, trastuzumab, lapatinib, brain/cerebral neoplasm/metastases and blood-brain barrier. We identified few and mostly small clinical studies. Study designs were very heterogeneous making comparisons on endpoints difficult. Overall survival for patients treated with trastuzumab varied from 8 to 25 months and 5.5 to 11 months for patients receiving lapatinib. The majority of studies were retrospective thus possibly biasing data. Only three studies were identified comparing trastuzumab to lapatinib. Conclusively, no solid data exist on how to treat patients with HER2-positive disease and brain metastases. Although continuous HER2-blockade is recommended by international consensus guidelines, it is still not evident which HER2-targeting agent should be preferred when brain metastases occur. The choice of chemotherapy to accompany the blockade is not obvious and we do not know if dual is better than single blockade. Further clinical trials are urgently needed.

Predictors and survival in patients with melanoma brain metastases

Brain metastases (BM) are one of the most frequent neurological complications of cancers. Melanoma is the third most common tumor to metastasize to the brain with a reported incidence of 10-40 %, and many patients have subclinical BM (>73 %). We computer-searched the clinical records of all our patients registered into a database to identify patients that presented or developed BM. A total of 49 patients with melanoma BM were included in our analysis. General time to brain metastases (TTBM) was 23 months. The nonparametric test between TTBM and the single variables showed an association between TTBM and Breslow thickness (p < 0.0076; Spearman's coefficient-0.411), ulceration (p = 0.0656; Spearman's coefficient-0.287) and positive sentinel lymph node (p < 0.0015; Spearman's coefficient-0.475). Performing multiple regression, positive SLN remained the only, statistically significant, predictive variable (p < 0.01). Regarding the first melanoma site, the axial sites were more likely to develop BM than peripheral ones (p < 0.001). The analysis of brain metastasis survival (BMS) with Kaplan-Meier curves has resulted in a median survival rate of 6 months (range 1-134 months) and was strongly related to response to treatment, number of parenchymal lesions, presence or absence of symptoms. The results of the current analysis revealed clinical and primary tumor characteristics associated with the development of BM, TTBM, and BMS. The SNL was found to be the strongest predictor for BM development.

Brain metastases in Asian HER2-positive breast cancer patients: anti-HER2 treatments and their impact on survival

BACKGROUND

In Asia, large-scale studies on anti-HER2 treatment in HER2-positive breast cancer patients with brain metastases are limited. We studied the treatment patterns of these patients in Asia to evaluate the impact of anti-HER2 treatment on the time to occurrence of brain metastases (TTBM) and survival after brain metastasis (BM).

METHODS

A retrospective study of HER2-positive breast cancer patients diagnosed with BM between January 2006 and December 2008 in six Asian countries was conducted. Demographics, tumour characteristics, treatment details, and events dates were collected from medical records.

RESULTS

Data from 280 patients were analysed. Before BM, 63% received anti-HER2 treatment. These patients had significantly longer TTBM than those without anti-HER2 treatment (median 33 vs 19 months; P<0.002). After BM, 93% received radiotherapy, 57% received chemotherapy, and 41% received anti-HER2 treatment (trastuzumab and/or lapatinib). Use of both anti-HER2 agents, primarily sequentially, after BM demonstrated the longest survival after BM and was associated with a significant survival benefit over no anti-HER2 treatment (median 26 vs 6 months; hazard ratio 0.37; 95% CI 0.19-0.72).

CONCLUSION

Anti-HER2 treatment before BM was associated with longer TTBM. Anti-HER2 treatment after BM was associated with a survival benefit, especially when both trastuzumab and lapatinib were utilised.

Therapeutic approaches for HER2-positive brain metastases: circumventing the blood-brain barrier

We aim to summarize data from studies of trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) and brain metastasis and to describe novel methods being developed to circumvent the blood-brain barrier (BBB). A literature search was conducted to obtain data on the clinical efficacy of trastuzumab and lapatinib in patients with HER2-positive MBC and brain metastasis, as well as the transport of therapeutic molecules across the BBB. Trastuzumab-based therapy is the standard of care for patients with HER2-positive MBC. Post hoc and retrospective analyses show that trastuzumab significantly prolongs overall survival when given after the diagnosis of central nervous system (CNS) metastasis; this is probably attributable to its control of extracranial disease, although trastuzumab may have a direct effect on CNS disease in patients with local or general perturbation of the BBB. In patients without a compromised BBB, trastuzumab is thought to have limited access to the brain, because of its relatively large molecular size. Several approaches are being developed to enhance the delivery of therapeutic agents to the brain. These include physical or pharmacologic disruption of the BBB, direct intracerebral drug delivery, drug manipulation, and coupling drugs to transport vectors. Available data suggest that trastuzumab extends survival in patients with HER2-positive MBC and brain metastasis. Novel methods for delivery of therapeutic agents into the brain could be used in the future to enhance access to the CNS by trastuzumab, thereby improving its efficacy in this setting.