Paget’s disease of the nipple

The widespread use of trastuzumab in the past decade has led to a significant and measureable improvement in the survival of patients with human epidermal growth factor receptor-2 (HER2) overexpressing breast cancer, and in many ways has redefined the natural history of this aggressive breast cancer subtype. Historically, survival in patients with HER2-positive disease was dictated by the systemic disease course, and what appears to be the central nervous system (CNS) tropism associated with HER2-amplified tumors was not clinically evident. With improved systemic control and prolonged survival, the incidence of brain metastases has increased, and CNS disease, often in the setting of well-controlled extracranial disease, is proving to be an increasingly important and clinically challenging cause of morbidity and mortality in patients with HER2-positive advanced breast cancer. This review summarizes the known clinical data for the systemic treatment of HER2-positive CNS metastases and includes information about ongoing clinical trials of novel therapies as well as emerging strategies for early detection and prevention.     

HER2-positive Breast Cancer Brain Metastases: Multiple Responses to Systemic Chemotherapy and Trastuzumab—a Case Report

Brain metastases from metastatic breast cancer typically occur in 10–15% of patients and are associated with survival of 3–6 months. Recent series have shown that women with HER2-postive metastatic breast cancer receiving the drug trastuzumab develop brain metastases more frequently than this, but also that continuation of trastuzumab after diagnosis of brain metastases in such patients is associated with extended survival. Authors have speculated that this is due to improved systemic control of disease; however, a possibility is that trastuzumab may have a beneficial effect on cerebral metastases themselves. We report the case of a woman with HER2-positive metastatic breast cancer who developed multiple brain metastases while on trastuzumab, in whom the addition of systemic chemotherapy to continued trastuzumab has produced multiple treatment responses associated with prolonged survival. This is the first report of its kind.     

Brain metastases: the HER2 paradigm.

Between 100,000 and 170,000 patients with cancer develop central nervous system (CNS) metastases each year in the U.S., of which approximately 20% carry a primary diagnosis of breast cancer. As a consequence of improvements in systemic therapy, which have allowed patients to live longer with advanced cancer, CNS metastases are emerging as an important sanctuary site, and the incidence may be increasing in patients with particular tumor subtypes. Unless there are improvements in the treatment of CNS disease, a growing proportion of patients may be at risk of experiencing both morbidity and mortality as a result of uncontrolled CNS progression, often at a time when their extra-CNS disease is apparently under control. This article reviews changes in the epidemiology and natural history of women with brain metastases from HER2-positive breast cancer over the last decade and presents the therapeutic challenges and opportunities that have arisen in this setting. First, the apparent increase in CNS disease among women with HER2-positive breast cancer, relative to historical controls, is discussed, followed by consideration of potential causes of this observation. Next, the implications of CNS disease, in terms of prognosis and the potential development of preventive strategies are considered. Finally, new developments in systemic approaches to the treatment of CNS disease, including cytotoxic chemotherapy and targeted therapy, are explored.     

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.     

Métastases cérébrales de cancer du sein : traitements systémiques

An increase in the incidence of breast cancer patients with brain metastases has been observed over the last years, mainly because the recent development of new drugs including therapies targeting HER2 (human epidermal growth factor receptor 2) resulted in an increased survival of these patients. With HER2+ patients living longer and the well-known neurotropism of HER2+ tumour cells, the resulting high incidence of brain metastases is not really surprising. Moreover, brain metastases more often occur within a context of existing extracranial metastases. These need to be treated at the same time in order to favourably impact patients’ survival. Consequently, the management of breast cancer patients with brain metastases clearly relies on a multidisciplinary approach, including systemic treatment. A working group including neuro-oncologists, neurosurgeons, radiation oncologists and oncologists was created in order to provide French national guidelines for the management of brain metastases within the “Association des neuro-oncologues d’expression française” (ANOCEF). The recommendations regarding the systemic treatment in breast cancer patients are reported here including key features of their management.     

Breast cancer brain metastases: differences in survival depending on biological subtype,RPA RTOG prognostic class and systemic treatment after whole-brain radiotherapy (WBRT)

Background: Patients with breast cancer brain metastasis are a heterogeneous group in relation to tumor biology and outcome.Materials and methods: The group of 222 breast cancer patients with brain metastasis was divided into three biological subgroups. The propensity of biological subtypes for metastases to the brain and survivals depending on biological subtype, recursive partitioning analysis of Radiation Therapy Oncology Group (RPA RTOG) prognostic class and the use of systemic treatment after whole-brain radiotherapy were assessed.Results: The rate of patients with triple-negative, human epidermal growth factor receptor 2 (HER2)-positive and luminal breast cancer with brain metastases was 28%, 53% and 19%, respectively. Median survival from brain metastases in triple-negative, HER2-positive and luminal subtype was 3.7, 9 and 15 months, respectively. Median survival from brain metastases in RPA RTOG prognostic class I, II and III was 15, 11 and 3 months, respectively. In the luminal and in the triple-negative subtype, systemic therapy prolonged survival from 3 to 14 months and from 3 to 4 months, respectively. In HER2-positive subtype, median survival without further treatment, after chemotherapy and after chemotherapy with targeted therapy were 3, 8 and 11 months, respectively.Conclusions: HER2-positive and triple-negative breast cancers have special predilection for metastases to the brain. Survival from brain metastases depended on performance status and the use of systemic treatment.     

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 3 cm 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.     

Evolving standards of care and new challenges in the management of HER2-positive breast cancer

The management of human epidermal growth factor receptor (HER2)–positive breast cancer (BC) has rapidly evolved over the last 20 years. Major advances have led to US Food and Drug Administration approval of 7 HER2-targeted therapies for the treatment of early-stage and/or advanced-stage disease. Although oncologic outcomes continue to improve, most patients with advanced HER2-positive BC ultimately die of their disease because of primary or acquired resistance to therapy, and patients with HER2-positive early BC who have residual invasive disease after preoperative systemic therapy are at a higher risk of distant recurrence and death. The concept of treatment de-escalation and escalation is increasingly important to optimally tailor therapy for patients with HER2-positive BC and is a major focus of the current review. Research efforts in this regard are discussed as well as updates regarding the evolving standard of care in the (neo)adjuvant and metastatic settings, including the use of novel combination therapies. The authors also briefly discuss ongoing challenges in the management of HER2-positive BC (eg, intrinsic vs acquired drug resistance, the identification of predictive biomarkers, the integration of imaging techniques to guide clinical practice), and the treatment of HER2-positive brain metastases. Research aimed at superseding these challenges will be imperative to ensure continued progress in the management of HER2-positive BC going forward.     

PI3K pathway inhibitors for the treatment of brain metastases with a focus on HER2+ breast cancer

The incidence of breast cancer brain metastases has increased in recent years, largely due to improved control of systemic disease with human epidermal growth factor receptor 2 (HER2)-targeted agents and the inability of most of these agents to efficiently cross the blood–blood barrier (BBB) and control central nervous system disease. There is, therefore, an urgent unmet need for treatments to prevent and treat HER2+ breast cancer brain metastases (BCBMs). Aberrant activation of the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway is frequently observed in many cancers, including primary breast tumors and BCBMs. Agents targeting key components of this pathway have demonstrated antitumor activity in diverse cancers, and may represent a new treatment strategy for BCBMs. In preclinical studies, several inhibitors of PI3K and mTOR have demonstrated an ability to penetrate the BBB and down-regulate PI3K signaling, indicating that these agents may be potential therapies for brain metastatic disease. The PI3K inhibitor buparlisib (BKM120) and the mTOR inhibitor everolimus (RAD001) are currently under evaluation in combination with trastuzumab in patients with HER2+ BCBMs.     

Trastuzumab treatment in patients with breast cancer and metastatic CNS disease

Background: Patients with metastatic central nervous system (mCNS) disease progression from breast cancer have a poor prognosis and often develop associated neurological complications. Human epidermal growth factor receptor 2 (HER2)-positivity status increases the risk of developing mCNS disease. Trastuzumab is an mAb that targets HER2 and is known to extend survival across all stages of HER2-positive breast cancer.Design: This review considers evidence from preclinical and clinical studies examining the value of continuing trastuzumab treatment in patients who develop mCNS disease. A wealth of data from clinical studies showed that trastuzumab prolonged survival in patients with mCNS disease, compared with no trastuzumab treatment, by effectively controlling their non-CNS disease. Trastuzumab has also been shown to penetrate an impaired blood–brain barrier to a limited degree, such as during radiotherapy, and intrathecal delivery of trastuzumab to the central nervous system (CNS) has shown promise. Research efforts are focussing on improving the delivery of trastuzumab to the CNS.Conclusion: Evidence indicates that patients with mCNS disease from HER2-positive breast cancer should continue to receive trastuzumab to control HER2-positive metastases outside the CNS and receive established therapies to control the mCNS disease.     

Developmental therapeutics for patients with breast cancer and central nervous system metastasis: current landscape and future perspectives

Breast cancer is the second-leading cause of metastatic disease in the central nervous system (CNS). Recent advances in the biological understanding of breast cancer have facilitated an unprecedented increase of survival in a subset of patients presenting with metastatic breast cancer. Patients with HER2 positive (HER2+) or triple negative breast cancer are at highest risk of developing CNS metastasis, and typically experience a poor prognosis despite treatment with local and systemic therapies. Among the obstacles ahead in the realm of developmental therapeutics for breast cancer CNS metastasis is the improvement of our knowledge on its biological nuances and on the interaction of the blood–brain barrier with new compounds. This article reviews recent discoveries related to the underlying biology of breast cancer brain metastases, clinical progress to date and suggests rational approaches for investigational therapies.     

HER2 overexpressing metastatic breast cancer

Opinion statement More than 40,000 women in the United States die each year from metastatic breast cancer. Elucidation of HER2 and its role in malignant transformation has helped define a subset of aggressive breast cancer that may be relatively resistant to non-anthracycline-based therapies and hormonal agents, but responds to targeted molecular therapy. Trastuzumab, an antibody against HER2, has proven effective as single agent therapy in women with HER2 overexpressed metastatic breast cancer. Moreover, in combination with chemotherapy, trastuzumab has been shown to delay disease progression and improve overall survival for women with HER2-positive advanced breast cancer. The combination of chemotherapy and trastuzumab is emerging as a standard of care in women with HER2 overexpressed metastatic breast cancer. Several combination regimens using trastuzumab with taxanes, vinca alkaloids, or platinum compounds have demonstrated efficacy in first- and second-line treatment settings. However, the development of anthracycline-based combinations has been limited by concerns of related cardiotoxicity. Newer multi-agent regimens are in development. The optimal combination, duration, and sequence of trastuzumab therapy remain unknown in patients with HER2-positive metastatic disease. The role of continuing treatment after disease progression is also unclear. Evidence from some retrospective analyses suggest HER2-positive tumors are relatively resistant to tamoxifen and perhaps more responsive to aromatase inhibitors, although such data are inconclusive. HER2 status should not be used routinely for clinical decision making regarding hormonal therapy options. Several ongoing trials are attempting to address these and other issues related to HER2 testing to select the most appropriate candidates for these emerging therapies. While many questions remain, the treatment of HER2 overexpressing metastatic breast cancer is rapidly evolving, and represents a new approach to treatment in oncology.     

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.     

New challenges and opportunities in the management of brain metastases in patients with ErbB2-positive metastatic breast cancer

The introduction of trastuzumab for the treatment of tumors that overexpress ErbB2 (also known as HER2) has contributed significantly to recent improvements in systemic therapy for advanced breast cancer. The advances in systemic therapy have highlighted an increasing prevalence of central nervous system involvement in patients with ErbB2-positive breast cancer and a consequent need for new treatment options for brain metastases. Just as ErbB2-targeted systemic therapy has given rise to this challenge, so too could targeted therapy represent an opportunity to meet it. This Review considers the potential for targeted therapy to facilitate effective management of brain metastases in patients with ErbB2-positive breast cancer, and discusses in particular the data currently available in this setting for lapatinib, an orally available small-molecule tyrosine kinase inhibitor of ErbB1 and ErbB2.     

Local and systemic therapy in breast cancer patients with central nervous system metastases

Purpose

As survival of patients with central nervous system (CNS) metastases from breast cancer is poor and incidence rates are increasing, there is a growing need for better treatment strategies. In the current study, the efficacy of local and systemic therapies was analyzed in breast cancer patients with CNS metastases.

Methods

Medical records from breast cancer patients with brain and/or leptomeningeal metastases (LM) treated at a tertiary referral center and a teaching hospital between 2010 and 2020 were retrospectively studied. Main outcomes of interest were overall survival (OS) and CNS progression free survival. Analyses were performed among patients with brain metastases (BM) and patients with LM, for the different systemic and local therapies for CNS metastases, and for subgroups based on breast cancer subtypes.

Results

We identified 155 patients, 97 with BM and 58 with LM. Median OS was 15.9 months for patients with BM and 1.5 months for patients with LM. Median OS was significantly longer for HER2-positive patients with BM (22.8 months) vs triple negative (8.4 months) and hormone receptor positive/HER2-negative (5.9 months) (P?<?0.001). Patients with BM receiving both local and systemic therapy also had a longer median OS (21.8 months), compared to the other three subgroups (local therapy only: 9.9 months, systemic therapy only: 4.3 months, no therapy: 0.5 months, P?<?0.001). No significant difference in OS was observed between different systemic treatment regimens.

Conclusion

Breast cancer patients with BM show longest median OS when the subtype is HER2-positive and when they are treated with both local and systemic therapy.

     

New insights and emerging therapies for breast cancer brain metastases

Breast cancer brain metastases (BCBMs) are the second most frequent secondary central nervous system metastases following those associated with non-small-cell lung cancer. It is increasingly evident that BCBM arises as a function of the biology of the primary tumor and the metastatic niche, which combine to create a unique microenvironment in the brain impacting both metastatic colonization and therapeutic response. Clinical outcomes are improving for BCBM patients as a result of modern combinatorial therapies, challenging the traditionally nihilistic approach to this patient subgroup. This review will focus on the breast cancer subtypes with the highest incidence of BCBM-human epidermal growth factor receptor 2 (HER2)-positive breast cancer, and triple-negative (estrogen receptor [ER]-negative, progesterone receptor [PR]-negative, and HER2-negative) breast cancer (TNBC)-and will characterize differences in the clinical behavior of brain metastases that arise from these different subtypes. We will also highlight some of the recent preclinical studies that may shed light on the biological mechanisms and mediators underlying brain metastases. Finally, we will review published and current prospective trials of systemic therapies specifically for BCBM, including novel pathway-specific therapies.     

Treatment strategies for breast cancer brain metastases

Brain metastases from breast cancer (BCBM) constitute the second most common cause of brain metastasis (BM), and the incidence of these frequently lethal lesions is currently increasing, following better systemic treatment. Patients with ER-negative and HER2-positive metastatic breast cancer (BC) are the most likely to develop BM, but if this diagnosis remains associated with a worse prognosis, long survival is now common for patients with HER2-positive BC. BCBM represents a therapeutic challenge that needs a coordinated treatment strategy along international guidelines. Surgery has always to be considered when feasible. It is now well established that stereotaxic radiosurgery allows for equivalent control and less-cognitive toxicities than whole-brain radiation therapy, which should be delayed as much as possible. Medical treatment for BCBM is currently a rapidly evolving field. It has been shown that the blood–brain barrier (BBB) is often impaired in macroscopic BM, and several chemotherapy regimens, antibody–drug conjugates and tyrosine-kinase inhibitors have been shown to be active on BCBM and can be part of the global treatment strategy. This paper provides an overview of the therapeutic option for BCBM that is currently available and outlines potential new approaches for tackling these deadly secondary tumours.Subject terms: Breast cancer, Metastasis     

激素受体阳性乳腺癌脑转移药物治疗研究进展

目的 乳腺癌是仅次于肺癌最易发生脑转移的原发肿瘤.激素受体阳性乳腺癌是转移性乳腺癌的主体,脑转移是该类患者的主要死亡原因,但目前对于激素受体阳性乳腺癌脑转移(breast cancer brain metastases,BCBM)的有效治疗报道较少.本研究旨探讨激素受体阳性BCBM药物治疗的相关研究进展.方法 应用PubMed及CNKI期刊全文数据库检索系统,以"乳腺癌、脑转移和激素受体阳性乳腺癌"等为,检索2005-01-2016-06相关文献,共检测到中文文献128条,英文文献55条.纳入标准:1)BCBM的危险因素及其预后;2)BCBM的当前治疗选择;3)激素受体阳性BCBM药物治疗.根据纳入标准,符合分析的文献25篇.结果限制BCBM药物治疗进展的主要原因是血脑屏障的存在.激素在BCBM治疗中的疗效尚不明确,但有大量个案报道他莫昔芬等内分泌药物对BCBM治疗有效.非对照试验表明某些细胞毒类药物,如卡培他滨、替莫唑胺(temozolomide,TMZ)和卡莫司汀晶片植入剂,对激素受体阳性BCBM有效,但没有足够证据支持具体的治疗方案.免疫抑制剂abemaciclib在激素受体阳性BCBM患者中的应用正处于Ⅱ期临床试验阶段.虽然高分子药物难以通过完整的血脑屏障,但研究证实部分单克隆抗体,如曲妥珠单抗和贝伐单抗,对BCBM治疗有效.纳米药物传递系统能提高中枢神经系统药物转移,有较好发展前景.由纳米颗粒包裹的多柔比星和etirinotecanpegol对治疗激素受体阳性BCBM有一定的疗效.结论尽管目前没有专门批准用于激素受体阳性BCBM系统治疗的药物,但有大量的临床试验正在进行中,将为临床治疗带来启示.     

Biological subtypes and survival outcomes in breast cancer patients with brain metastases (study of the anatolian society of medical oncology)

Background: The aim of this study is to determine the relationship between the survival outcomes and biological subtype in breast cancer patients with brain metastases. Methods: We retrospectively evaluated clinical data from 422 breast cancer patients with brain metastases between 2001 and 2011 from referral centers in Turkey. The study population was divided into four biological subtypes according to their hormone receptor status and HER2 expression. Results: Systemic treatment prolonged median overall survival (OS) after brain metastases in the entire group (14 vs. 3.2 months, p < 0.001). It also prolonged median OS after brain metastases in the triple negative (7.5 vs. 1.6 months, p = 0.010) and luminal A (14.3 vs. 7.1 months, p = 0.003) subgroups. The median OS for untreated patients, chemotherapy and/or hormonal therapy receiving patients, and chemotherapy and/or hormonal therapy plus targeted therapy receivers was 2, 5.8, and 17.7 months, respectively (p < 0.001), in the HER2-overexpressing subgroup. In the luminal B subgroup, it was 3.7, 5.3, and 15.4 months, respectively (p = 0.003). Conclusions: The use of systemic therapy improves OS after brain metastases in all biological subgroups. Targeted therapies also improve OS after brain metastases in HER2-positive patients. The combined use of targeted therapies and lapatinib are superior to single use and trastuzumab, respectively, in these patients.     

HER2阳性型乳腺癌脑转移的研究进展

近年来曲妥珠单抗的广泛应用大大提高了HER2（人表皮生长因子受体 2）过度表达乳腺癌患者的生存率,在全身性控制率提高和生存期延长的同时,脑转移瘤的发病率也有所增加;同时,脑转移是造成HER2阳性型乳腺癌晚期患者死亡的一项越来越重要的具有临床挑战性的因素——常常是在颅外疾病控制良好的情况下。本文将HER2阳性型乳腺癌脑转移的早期检测和预防的价值,靶向治疗的进展及新靶向药物的开发情况加以总结。