Longterm remission of multiple brain metastases with tamoxifen

Anti-Hormonal Therapy in Breast Cancer and Its Effect on the Blood-Brain Barrier

The molecular receptor status of breast cancer has implications for prognosis and long-term metastasis. Although metastatic luminal B-like, hormone-receptor-positive, HER2−negative, breast cancer causes brain metastases less frequently than other subtypes, though tumor metastases in the brain are increasingly being detected of this patient group. Despite the many years of tried and tested use of a wide variety of anti-hormonal therapeutic agents, there is insufficient data on their intracerebral effectiveness and their ability to cross the blood-brain barrier. In this review, we therefore summarize the current state of knowledge on anti-hormonal therapy and its intracerebral impact and effects on the blood-brain barrier in breast cancer.

Systemic Therapy Approaches for Breast Cancer Brain and Leptomeningeal Metastases

OPINION STATEMENT

Brain metastasis arising from breast cancer is associated with a poor prognosis. Various systemic chemotherapy and targeted therapies which are effective against breast cancer often fail to provide benefits against brain metastasis. This is mainly due to limited penetration of the therapies across the blood-brain barrier, and divergent evolution of brain metastasis compared to the primary tumor. Thus, brain metastasis is typically treated upfront with local therapies, such as surgery and radiation, followed by systemic therapies. Systemic therapies with CNS permeability are favored in patients with brain metastasis. This paper reviews various systemic therapy options for breast cancer brain metastasis.

Intracranial Response Rate in Patients with Breast Cancer Brain Metastases after Systemic Therapy

Simple Summary

For many years, patients with breast cancer and brain metastases were excluded from participation in clinical trials. It was believed that anticancer drugs could not cross the blood–brain barrier. However, recent evidence strongly suggests that some drugs can act against brain metastases, with the greatest intracranial response rate reported in the case of capecitabine, neratinib plus capecitabine, trastuzumab deruxtecan and tucatinib plus trastuzumab and capecitabine. In this article, we discuss the achievements in systemic therapy of breast cancer patients with brain metastases. We stress on the newest clinical trial results which indicate tremendous progress in HER2-positive breast cancer. On the other hand, in patients with triple-negative breast cancer or hormone-receptor-positive brain metastases, much fewer compounds were discovered. Based on the presented results, patients with active brain metastases should be routinely included in clinical trials with novel agents.

Abstract

Brain metastases are detected in 5% of patients with breast cancer at diagnosis. The rate of brain metastases is higher in HER2-positive and triple-negative breast cancer patients (TNBC). In patients with metastatic breast cancer, the risk of brain metastases is much higher, with up to 50% of the patients having two aggressive biological breast cancer subtypes. The prognosis for such patients is poor. Until recently, little was known about the response to systemic therapy in brain metastases. The number of trials dedicated to breast cancer with brain metastases was scarce. Our review summarizes the current knowledge on this topic including very significant results of clinical trials which have been presented very recently. We focus on the intracranial response rate of modern drugs, including new antibody–drug conjugates, HER2- targeted tyrosine kinase inhibitors and other targeted therapies. We highlight the most effective and promising drugs. On the other hand, we also suggest that further efforts are needed to improve the prognosis, especially patients with TNBC and brain metastases. The information contained in this article can help oncologists make treatment-related decisions.

Targeting brain metastases in breast cancer

Brain metastases (BMs) are an important source of morbidity and mortality in patients with metastatic breast cancer (BC). As survival of patients with advanced BC considerably improved thanks to research advancements and new therapeutic approaches, the apparent incidence of BMs is increasing. Local interventions, in the form of either surgical resection or radiation therapy, remain the mainstay in the management of BMs. Systemic treatments are typically used to complement local strategies to further improve and maintain control of central nervous system (CNS) disease. Although high-level evidence data about the impact of the blood-brain barrier (BBB), as well as the efficacy of anti-cancer agents on BMs and differentials between the systemic compartment and CNS are still scant, our understanding of the activity of systemic treatments with impact on BMs is rapidly evolving. Novel anti-HER2 agents, such as tucatinib, ado-trastuzumab emtansine, trastuzumab deruxtecan and neratinib, have shown intracranial efficacy. Current research efforts are ongoing not only to clarify the activity of existing treatments on the CNS, as well as to develop new drugs and innovative multi-modality approaches. This review will encompass the current treatment landscape of BMs arising from BC, with a focus on recent advancements in the field and investigational approaches.

Is Molecular Tailored-Therapy Changing the Paradigm for CNS Metastases in Breast Cancer?

Breast cancer (BC) is the second most common tumour spreading to the central nervous system (CNS). The prognosis of patients with CNS metastases depends on several parameters including the molecular assessment of the disease. Although loco-regional treatment remains the best approach, systemic therapies are acquiring a role leading to remarkable long-lasting responses. The efficacy of these compounds diverges between tumours with different molecular assessments. Promising agents under investigation are drugs targeting the HER2 pathways such as tucatinib, neratinib, pyrotinib, trastuzumab deruxtecan. In addition, there are several promising agents under investigation for patients with triple-negative brain metastases (third-generation taxane, etirinotecan, sacituzumab, immune-checkpoint inhibitors) and hormone receptor-positive brain metastases (CDK 4/5, phosphoinositide-3-kinase-mammalian target of rapamycin [PI3K/mTOR] inhibitors). Also, the systemic treatment of leptomeningeal metastases, which represents a very negative prognostic site of metastases, is likely to change as several compounds are under investigation, some with interesting preliminary results. Here we performed a comprehensive review focusing on the current management of CNS metastases according to molecular subtypes, site of metastases (leptomeningeal vs brain), and systemic treatments under investigation.

Tamoxifen suppresses brain metastasis of estrogen receptor-deficient breast cancer by skewing microglia polarization and enhancing their immune functions

Background

Brain metastasis of breast cancer exhibits exceedingly poor prognosis, and both triple negative (TN) and Her2⁺ subtypes have the highest incidence of brain metastasis. Although estrogen blockers are considered to be ineffective for their treatment, recent evidence indicates that estrogen blockade using tamoxifen showed certain efficacy. However, how estrogen affects brain metastasis of triple negative breast cancer (TNBC) remains elusive.

Methods

To examine the effect of estrogen on brain metastasis progression, nude mice were implanted with brain metastatic cells and treated with either estrogen supplement, tamoxifen, or ovariectomy for estrogen depletion. For clinical validation study, brain metastasis specimens from pre- and post-menopause breast cancer patients were examined for microglia polarization by immunohistochemistry. To examine the estrogen-induced M2 microglia polarization, microglia cells were treated with estrogen, and the M1/M2 microglia polarization was detected by qRT-PCR and FACS. The estrogen receptor-deficient brain metastatic cells, SkBrM and 231BrM, were treated with conditioned medium (CM) derived from microglia that were treated with estrogen in the presence or absence of tamoxifen. The effect of microglia-derived CM on tumor cells was examined by colony formation assay and sphere forming ability.

Results

We found that M2 microglia were abundantly infiltrated in brain metastasis of pre-menopausal breast cancer patients. A similar observation was made in vivo, when we treated mice systemically with estrogen. Blocking of estrogen signaling either by tamoxifen treatment or surgical resection of mice ovaries suppressed M2 microglial polarization and decreased the secretion of C-C motif chemokine ligand 5, resulting in suppression of brain metastasis. The estrogen modulation also suppressed stemness in TNBC cells in vitro. Importantly, estrogen enhanced the expression of signal regulatory protein α on microglia and restricted their phagocytic ability.

Conclusions

Our results indicate that estrogen promotes brain metastasis by skewing polarity of M2 microglia and inhibiting their phagocytic ability, while tamoxifen suppresses brain metastasis by blocking the M2 polarization of microglia and increasing their anti-tumor phagocytic ability. Our results also highlight a potential therapeutic utility of tamoxifen for treating brain metastasis of hormone receptor-deficient breast cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13058-021-01412-z.

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.

Brain metastases from breast cancer may respond to endocrine therapy: report of two cases

Brain metastases from breast cancer have a poor prognosis. There have been few cases reported where patients with breast cancer and brain metastases respond well to endocrine therapy (tamoxifen or letrozole). Here, we report the cases of two breast cancer patients with brain metastases who responded to medroxyprogesterone acetate and fulvestrant, respectively. These cases indicate that endocrine therapy could be very effective in the management of brain metastases from breast carcinoma.

Continued Endocrine Therapy Is Associated with Improved Survival in Patients with Breast Cancer Brain Metastases

PURPOSE

Brain metastases (BMs) are a rare but devastating condition in estrogen receptor (ER)-positive metastatic breast cancer (MBC). Although endocrine therapy (ET) is the mainstay of treatment in this disease subtype, only case reports have been published concerning the activity of ET in BMs henceforth. Therefore, we aimed to systematically investigate the impact of ET after diagnosis of BM on outcome and clinical course of disease in patients with ER-positive MBC.

EXPERIMENTAL DESIGN

Patient characteristics, detailed information about BMs including diagnosis-specific graded prognostic assessment class (DS-GPA), and clinical outcome were obtained by retrospective chart review for all patients treated for ER-positive breast cancer BMs between 1990 and 2017 at an academic care center. Overall survival (OS) was measured as the interval from diagnosis of BM until death or last date of follow-up.

RESULTS

Overall, 198 patients [female: 195/198 (98.5%); male: 3/198 (1.5%)] with ER-positive breast cancer BMs were available for this analysis. Eighty-eight of 198 patients (44.4%) received ET after diagnosis of BM including aromatase inhibitors (AIs; letrozole, anastrozole, exemestane), tamoxifen, and fulvestrant. Median OS was significantly longer in patients receiving ET after diagnosis of BM compared with patients who did not (15 vs. 4 months, P < 0.001; log-rank test). No significant difference in terms of OS was observed between patients receiving AIs, tamoxifen, or fulvestrant. In patients with concomitant leptomeningeal carcinomatosis (LC), ET prolonged median OS significantly as well (7 vs. 3 months, P = 0.012; log-rank test). In a multivariate analysis including DS-GPA and ET, only treatment with ET after diagnosis of BM (HR, 0.69; 95% confidence interval, 0.48-0.99; P = 0.046) was associated with prognosis (Cox regression model).

CONCLUSIONS

Continuing ET after BM diagnosis was associated with a significantly prolonged OS in this large single-center cohort. No substantial differences between substances were observed. These findings should be validated in a prospective cohort.

Prolonged Stabilization of Multiple and Single Brain Metastases from Breast Cancer with Tamoxifen. Report of Three Cases

Cancer frequently metastasizes to the brain, and such lesions, whether multiple or solitary, have a poor prognosis, despite all efforts to treat them. There have been recent sporadic reports of brain metastases from breast cancer responding for some years to antiestrogens (particularly tamoxifen) or bromocryptine. We report three cases of brain metastasis from cancer – two multiple and one a solitary lesion. The long survival of the patients – two for 5 years and one for 6 years, with more than an acceptable quality of life – should prompt therapeutic trials to test tamoxifen and designed to assess its effects on a sizable number of patients.

Breast Cancer in the Central Nervous System: Multidisciplinary Considerations and Management

Breast cancer is the second most common primary tumor associated with central nervous system (CNS) metastases. Patients with metastatic HER2-positive or triple-negative (estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, HER2-negative) breast cancer are at the highest risk of developing parenchymal brain metastases. Leptomeningeal disease is less frequent but is distributed across breast cancer subtypes, including lobular breast cancer. Initial treatment strategies can include surgery, radiation, intravenous or intrathecal chemotherapy, and/or targeted approaches. In this article, we review the epidemiology of breast cancer brain metastases, differences in clinical behavior and natural history by tumor subtype, and important considerations in the multidisciplinary treatment of these patients. We will highlight new findings that impact current standards of care, clinical controversies, and notable investigational approaches in clinical testing.

Targeted therapy of brain metastases: latest evidence and clinical implications

Brain metastases (BM) occur in 20-40% of patients with cancer and 60-75% of patients with BM become symptomatic. Due to an aging population and advances in the treatment of primary cancers, patients are living longer and are more likely to experience complications from BM. The diagnosis of BM drastically worsens long-term survival rates, with multiple metastases being a poor prognostic factor. Until recently, the mainstay of treatment consisted of stereotactic radiosurgery (SRS), surgical resection, whole brain radiation therapy (WBRT), or a combination of these modalities. Systemic chemotherapy has been felt largely ineffective in the treatment of BM due to the presence of the blood-brain barrier (BBB), which includes efflux pumps on brain capillaries. Over the past decade however, researchers have identified therapeutic agents that are able to cross the BBB. These findings could make a multimodality treatment approach possible, consisting of surgery, radiation, immunotherapy, and targeted therapy, which could lead to better disease control in this patient population and prolong survival. In this review, we discuss present evidence on available targeted therapies and their role in the treatment of BM from primary tumors with the highest prevalence of central nervous system (CNS) involvement, specifically non-small cell lung cancer (NSCLC), breast cancer melanoma, and renal cell carcinoma.

A Case of Breast Cancer Brain Metastasis with a 16-Year Time Interval without Evidence of Cancer Recurrence

The median time of brain metastasis from the diagnosis of breast cancer is approximately 3 years. In this case report, a 69-year-old woman demonstrated cerebellar ataxia. Brain magnetic resonance imaging revealed enhanced lesions in bilateral cerebellar hemispheres. She had undergone surgery, radiation, and chemotherapy for uterine and breast cancer 24 years prior and 16 years prior, respectively. Although she had not received any anticancer treatment for 10 years, no recurrences were identified using whole body scans. A partial tumor resection was performed and the histological diagnosis was an adenocarcinoma from breast cancer. As no extracranial lesions were found, gamma-knife irradiation was performed, without additional systemic chemotherapy. One month posttreatment, the tumors dramatically reduced in size and the patient completely recovered from cerebellar ataxia. Systemic chemotherapy is not always required for brain metastasis from breast cancer with a long interval period, as long as no evidence of extracranial recurrence is detected.

Challenges in the treatment of hormone receptor-positive, HER2-negative metastatic breast cancer with brain metastases

Brain metastases are a major cause of morbidity and mortality for women with hormone receptor (HR)-positive breast cancer, yet little is known about the optimal treatment of brain disease in this group of patients. Although these patients are at lower risk for brain metastases relative to those with HER2-positive and triple-negative disease, they comprise the majority of women diagnosed with breast cancer. Surgery and radiation continue to have a role in the treatment of brain metastases, but there is a dearth of effective systemic therapies due to the poor penetrability of many systemic drugs across the blood-brain barrier (BBB). Additionally, patients with brain metastases have long been excluded from clinical trials, and few studies have been conducted to evaluate the safety and effectiveness of systemic therapies specifically for the treatment of HER2-negative breast cancer brain metastases. New approaches are on the horizon, such as nanoparticle-based cytotoxic drugs that have the potential to cross the BBB and provide clinically meaningful benefits to patients with this life-threatening consequence of HR-positive breast cancer.

The Impact of Gonadal Hormones on the Expression of Human Neurological Disorders

The effects of gonadal steroids on neurological well-being and disease constitute a rich and rapidly expanding area of basic and clinical neuroscience. Gonadal hormones exert potent effects on monoaminergic, cholinergic and peptidergic pathways as well as neurosteroidogenesis which, in turn, impact normal brain organization and function. A spectrum of human neurological conditions are influenced by hormonal fluctuations associated with the menstrual cycle, pregnancy, the menopause and use of oral contraceptives. An appreciation of these relationships may facilitate the development of specific hormonal and anti-hormonal therapies for neurological disorders as disparate as catamenial epilepsy and acute intermittent porphyria.

Breast cancer brain metastases: the last frontier

Breast cancer is a common cause of brain metastases, with metastases occurring in at least 10–16 % of patients. Longer survival of patients with metastatic breast cancer and the use of better imaging techniques are associated with an increased incidence of brain metastases. Unfortunately, patients who develop brain metastases tend to have poor prognosis with short overall survival. In addition, brain metastases are a major cause of morbidity, associated with progressive neurologic deficits that result in a reduced quality of life. Tumor subtypes play a key role in prognosis and treatment selection. Current therapies include surgery, whole-brain radiation therapy, stereotactic radiosurgery, chemotherapy and targeted therapies. However, the timing and appropriate use of these therapies is controversial and careful patient selection by using available prognostic tools is extremely important. This review will focus on current treatment options, novel therapies, future approaches and ongoing clinical trials for patients with breast cancer brain metastases.

Evaluation of the pharmacological activities of RAD1901, a selective estrogen receptor degrader

Endocrine therapy, using tamoxifen or an aromatase inhibitor, remains a first-line treatment for estrogen receptor 1 (ESR1) positive breast cancer. However, tumor resistance limits the duration of response. The clinical efficacy of fulvestrant, a selective ER degrader (SERD) that triggers receptor degradation, has confirmed that ESR1 often remains engaged in endocrine therapy resistant cancers. Recently developed, selective ER modulators (SERMs)/SERD hybrids (SSHs) that facilitate ESR1 degradation in breast cancer cells and reproductive tissues have been advanced as an alternative treatment for advanced breast cancer, particularly in the metastatic setting. RAD1901 is one SSH currently being evaluated clinically that is unique among ESR1 modulators in that it readily enters the brain, a common site of breast cancer metastasis. In this study, RAD1901 inhibited estrogen activation of ESR1 in vitro and in vivo, inhibited estrogen-dependent breast cancer cell proliferation and xenograft tumor growth, and mediated dose-dependent downregulation of ESR1 protein. However, doses of RAD1901 insufficient to induce ESR1 degradation were shown to result in the activation of ESR1 target genes and in the stimulation of xenograft tumor growth. RAD1901 is an SSH that exhibits complex pharmacology in breast cancer models, having dose-dependent agonist/antagonist activity displayed in a tissue-selective manner. It remains unclear how this unique pharmacology will impact the utility of RAD1901 for breast cancer treatment. However, being the only SERD currently known to access the brain, RAD1901 merits evaluation as a targeted therapy for the treatment of breast cancer brain metastases.

Brain metastases of breast cancer

Brain metastases of breast cancer remain a difficult problem for clinical management. Their incidence appears to be increasing, which is likely due to longer survival times for advanced breast cancer patients as well as additional and improved tools for detection. Molecular features of tumors associated with this syndrome are not yet understood. In general, survival may be improving for brain metastases due to better local control in the CNS, as well as improvements in systemic disease management. Selected patients with brain metastases are able to undergo surgical resection, which has been associated with extended disease control in some patients. However, whole-brain radiation has been the mainstay for treatment for most patients. Stereotactic radiosurgery is playing an increasing role in the primary treatment of brain metastases, as well as for salvage after whole-brain radiation. Recent series have reported median survivals of 13 months or longer with stereotactic radiosurgery. Further improvements in radiation-based approaches may come from ongoing studies of radiosensitizing agents. The ability of systemic treatments to impact brain metastases has been debated, and specific treatment regimens have yet to be defined. New approaches include chemotherapy combinations, biologic therapies and novel drug-delivery strategies.

Brain metastases

Brain metastases are the most frequent neurological complication of cancer and the most common brain tumour type. Lung and breast cancers, and melanoma are responsible for up to three-quarters of metastatic brain lesions. Most patients exhibit either headache, seizures, focal deficits, cognitive or gait disorders, which severely impair the quality of life. Brain metastases are best demonstrated by MRI, which is sensitive but non-specific. The main differential diagnosis includes primary tumours, abscesses, vascular and inflammatory lesions. Overall prognosis is poor and depends on age, extent and activity of the systemic disease, number of brain metastases and performance status. In about half of the patients, especially those with widespread and uncontrolled systemic malignancy, death is heavily related to extra-neural lesions, and treatment of cerebral disease doesn't significantly improve survival. In such patients the aim is to improve or stabilize the neurological deficit and maintain quality of life. Corticosteroids and whole-brain radiotherapy usually fulfill this purpose. By contrast, patients with limited number of brain metastases, good performance status and controlled or limited systemic disease, may benefit from aggressive treatment as both quality of life and survival are primarily related to treatment of brain lesions. Several efficacious therapeutic options including surgery, radiotherapy and chemotherapy are available for these patients.

[Systemic treatment of brain metastases from breast cancer: cytotoxic chemotherapy and targeted therapies]

Prevalence of brain metastases is increasing in breast cancer. Brain metastases represent a poor-prognosis disease for which local treatments continue to play a major role. In spite of the presence of a physiological blood-brain barrier limiting their activity, some systemic treatments may display a significant antitumor activity at the central nervous system level. In HER2-positive metastatic breast cancer with brain metastases not previously treated with whole brain radiotherapy, capecitabine and lapatinib combination obtains a volumetric reponse in two thirds of patients (LANDSCAPE study). If confirmed, these results could modify in selected patients the layout of therapeutic strategies. Promoting novel targeted approaches and innovative therapeutic combinations is a critical need to improve survival of breast cancer patients with brain metastases.

Chemotherapy as primary treatment for brain metastases from breast cancer: analysis of 115 one-year survivors

PURPOSE

Given the potential toxicity of whole brain radiotherapy, we introduced systemic therapy as possible primary treatment for brain metastases (BM) from breast cancer. This study aims to evaluate the feasibility of this therapeutic approach.

METHODS

Review of 115 breast cancer patients treated for BM with at least 1 year of follow-up.

RESULTS

Patients with single BM without extracranial disease were usually treated with surgery, patients with multiple BM and controlled extracranial disease usually with RT, and those with progressive extracranial disease usually with systemic therapy as primary treatment for BM. Primary treatment for BM was surgery in 30 patients, RT in 26 patients, RT combined with systemic therapy in 33 patients, and systemic therapy as single treatment in 27 patients (chemotherapy n = 20; hormonal therapy n = 7). Response rate to surgery was 100 %, to RT 85 %, to RT+systemic therapy 87 %, to chemotherapy 70 %, and to hormonal therapy 14 %. Duration of neurological response and of extracranial response to chemotherapy as single treatment was similar (8 and 7 months, respectively). Patients with single BM and patients without extracranial disease had a better survival but the difference was not significant.

CONCLUSION

Chemotherapy as single treatment for BM from breast cancer is feasible and should not be restricted to salvage treatment.

Plasma and cerebrospinal fluid pharmacokinetics of topotecan in a phase I trial of topotecan, tamoxifen, and carboplatin, in the treatment of recurrent or refractory brain or spinal cord tumors

PURPOSE

This study was designed to ascertain the dose-limiting toxicities (DLT) and maximally tolerated doses of the combination of fixed-dose tamoxifen and carboplatin, with escalating doses of topotecan, and to determine the pharmacokinetics of topotecan in the plasma and cerebrospinal fluid.

METHODS

Tamoxifen 100 mg po bid, topotecan 0.25, 0.5, 0.75, or 1.0 mg/m(2)/d IV, administered as a 72 h continuous infusion on days 1-3, followed by carboplatin AUC = 3, IV on day 3. Cycles were repeated every 4 weeks.

RESULTS

Seventeen patients received 39 cycles of treatment: median 2, (range 1-5). The tumors included glioblastoma (6), anaplastic astrocytoma (2), metastatic non-small cell (3), small cell lung (2), and one each with medulloblastoma, ependymoma, and metastatic breast or colon carcinoma. The median Karnofsky performance status was 70% (range 60-90%) and age: 52 (range 24-75). Eleven patients were female and six male. Toxicities included thrombocytopenia (2), neutropenia without fever lasting 6 days (1), DVT (2), and emesis (1). Topotecan levels, total and lactone, were measured prior to the end of infusion in plasma and cerebrospinal fluid (CSF). At 1.0 mg/m(2)/d, the median CSF/plasma ratio was 19.4% (range 15.1-59.1%). The total plasma topotecan in two pts with DLTs was 4.63 and 5.87 ng/ml, in three without DLTs at the same dose level the mean total plasma topotecan was 3.4 ng/ml (range 3.02-3.83). Plasma lactone levels were 33% of the total; CSF penetration was 20% of the total plasma levels. 4/8 pts with high-grade gliomas had stable disease (median: 3 cycles (range 2-5)). Two had minor responses. One patient with metastatic non-small cell and one with small cell lung cancer had objective PRs.

CONCLUSIONS

The recommended phase II doses are: tamoxifen 100 mg po bid, topotecan 0.75 mg/m(2)/d IV continuous infusion for 72 h, followed by carboplatin AUC = 3 IV on day 3. Measurable topotecan levels, both total and lactone, are observed in the CSF.

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 metastases in HER-2-overexpressing metastatic breast cancer: a treatment challenge

With improvements in diagnostic and therapeutic options and a corresponding improvement in survival, central nervous system (CNS) metastasis is becoming a more frequent diagnosis in breast cancer patients. It can be assumed that up to 30% of metastatic breast cancer (MBC) patients may experience CNS metastasis during the course of their disease. Moreover, it has been reported that patients with human epidermal growth factor receptor (HER)-2-overexpressing MBC are at a higher risk for CNS involvement. Whereas locoregional treatment modalities such as surgery, radiosurgery, and whole-brain radiotherapy still must be considered as the treatment of first choice, the armamentarium of systemic treatment modalities has been expanded by the introduction of small molecules such as the tyrosine kinase inhibitors. Rather than analyzing the risk factors for the development of CNS metastasis and reviewing the standard diagnostic and therapeutic approaches in patients with CNS involvement, this review focuses specifically on systemic treatment modalities in patients suffering from CNS metastasis from HER-2-overexpressing MBC.

Chemotherapy in breast cancer patients with brain metastases: have new chemotherapic agents changed the clinical outcome?

Brain metastasis occurs in 15-40% of cancer patients and is present in approximately 10-16% of patients with metastatic breast disease. However, little is known about prognostic factors enabling the early identification of breast cancer patients at risk of CNS metastases. Therapy for brain metastases should be based on several parameters, such as the assessment of prognostic variables, the extent of neurological and systemic disease, and its chemo-sensitivity to previously administered chemotherapy treatments. In view of the known close correlation between metastatic and primary tumor chemosensitivity, the type of chemotherapy chosen should depend more on the tumor histology than on the cerebral distribution of the single drug. More recent drugs with a high impact on the clinical outcome of metastatic breast cancer patients, such as taxanes or trastuzumab, play only a limited role in the treatment of brain metastases.

Excellent response to letrozole in brain metastases from breast cancer

Breast cancer with multiple parenchymal brain metastases carries an extremely poor outcome. Cranial radiotherapy improves survival by only a few months and the role of systemic therapy is marginal and largely unexplored. We report a patient with recurrent carcinoma of breast presenting with multiple bilateral cervical nodes and brain metastases manifesting as a right hemiparesis and facial nerve palsy, who was treated with palliative whole brain irradiation and letrozole. At the follow up at 20 months, neurological function had fully recovered, and both cerebral and extracerebral lesions had completely resolved, with calcification of the cerebral lesions. This report suggests that letrozole has beneficial effects both in extracranial and intracranial disease in hormone responsive metastatic breast cancer.

[Current management of brain metastases]

INTRODUCTION

Cerebral metastases occur in 15 to 20% of cancers and their incidence is increasing. The majority occur at an advanced stage of the disease, but metastasis may be the inaugural sign of cancer. The aim of treatments, which are often palliative, is to preserve the neurological status of the patient with the best quality of life.

STATE OF ART

Corticosteroids are widely used for symptomatic palliation, requiring close monitoring and regular dose adaptation. Antiepileptic drugs should be given only for patients who have had a seizure. In case of multiple cerebral metastases occurring at an advanced stage of the disease, whole brain radiation is the most effective therapy for rapid symptom control. However, radiotherapy moderately improves overall survival, which often depends on the progression of disseminated systemic disease. On the contrary, surgery is indicated in case of a solitary metastasis, particularly when the patient is young (less than 65 years), with good general status (Karnofsky greater than 70), and when the systemic disease is under control. Radiosurgery offers an attractive alternative for these patients with good prognostic factors and a small number of cerebral metastases (< or = 4).

PERSPECTIVES

Chemotherapy, considered in the past as not effective, is taking on a more important place in patients with multiple nonthreatening metastases from chemosensitive cancers (breast, testes...). Radiosurgery and whole brain radiotherapy are complementary techniques. Their respective role in the management of multiple metastases (< 4) remains to be further investigated.

CONCLUSIONS

Therapeutic options are increasingly effective to improve the functional prognosis of patients with cerebral metastases. Ideally, a multidisciplinary assessment offers the best choice of therapeutic modalities.

CNS complications of breast cancer: current and emerging treatment options

In general, the development of CNS metastases of breast cancer depends on several prognostic factors, including younger age and a negative hormone receptor status. Also, the presence of a breast cancer 1, early onset (BRCA1) germline mutation and expression of the human epidermal growth factor receptor 2 (Her2/neu) proto-oncogene seem to contribute to an increased rate of development of CNS metastases. The choice of appropriate therapy for brain metastases also depends on prognostic factors, including the age of the patient, the Karnofsky performance score, the number of brain metastases and the presence of systemic disease. Surgery followed by whole brain radiation therapy (WBRT) is generally restricted to ambulant patients with a single brain metastasis without active extracranial disease. In patients who have two to four metastases, stereotactic focal radiotherapy (i.e. radiosurgery) with or without WBRT is usually indicated. In the remainder of patients, WBRT alone provides adequate palliation. Although breast carcinoma is sensitive to chemotherapy, the role of chemotherapy in the treatment of brain metastases is still unclear. Objective responses after cyclophosphamide-based therapies were reported in studies performed in the 1980s. Subgroup analysis of data from a randomised study indicates that survival may improve if WBRT is combined with the radiosensitiser efaproxiral. Interestingly, the Her2/neu antibody trastuzumab, which does not cross the blood-brain barrier, produces systemic responses and enhanced survival, without a clear effect on brain metastases. Breast cancer constitutes the most common solid primary tumour leading to leptomeningeal disease. Clinical symptoms such as cranial nerve dysfunction or a cauda equina syndrome can be treated with local radiotherapy. A randomised study in patients with leptomeningeal disease secondary to breast cancer has revealed that intrathecal chemotherapy is associated with substantially more adverse effects than non-intrathecal treatment, without a clear benefit in terms of response or survival. Intramedullary metastasis is rare but often presents with a rapidly progressive myelopathy. Local radiotherapy may preserve neurological function. Epidural spinal cord metastasis occurs in approximately 4% of patients and can lead to paraplegia. A randomised study has shown that surgical intervention together with local radiotherapy is superior to local radiotherapy alone.

Chemotherapy and targeted molecular therapies for brain metastases

As therapy for systemic cancers improves, an increasing number of patients are developing brain metastases. Although conventional therapy with surgery, radiation therapy and radiosurgery has improved the outcome of a significant number of patients, many develop multiple lesions that are not amenable to standard treatments. In this review, the current role of chemotherapy and targeted molecular agents for brain metastases is summarized and future directions are discussed.

Letrozole for brain and scalp metastases from breast cancer—a case report

Brain metastases from breast cancer have a poor prognosis. There have been reports of patients with breast cancer and brain metastases responding well to tamoxifen therapy. We report a very unusual case of intact breast carcinoma with brain as well as scalp metastasis responding well to letrozole (aromatase inhibitor) therapy for a prolonged period of time.

Radiotherapy and chemotherapy of brain metastases

The authors have reviewed the results, the indications and the controversies regarding radiotherapy and chemotherapy of patients with newly diagnosed and recurrent brain metastases. Whole-brain radiotherapy, radiosurgery, hypofractionated stereotactic radiotherapy, brachytherapy and chemotherapy are the available options. New radiosensitizers and cytotoxic or cytostatic agents are being investigated. Adjuvant whole brain radiotherapy, either after surgery or radiosurgery, and prophylactic cranial irradiation in small-cell lung cancer are discussed, taking into account local control, survival, and risk of late neurotoxicity. Increasingly, the different treatments are tailored to the different prognostic subgroups, as defined by Radiation Therapy Oncology Group RPA Classes.

The pathogenesis and treatment of brain metastases: a comprehensive review

Brain metastases are the most common intracranial tumors and their incidence is increasing. Untreated brain metastases are associated with a poor prognosis and a poor performance status. The role of surgery in the management of multiple brain metastases is still controversial. As more than 70% of patients have multiple metastases at the time of diagnosis, whole brain radiotherapy is the treatment of choice in most cases. Brain metastases are an ideal target for stereotactic radiosurgery, as they are better circumscribed than primary brain tumors. Currently, chemotherapy has a limited role in the treatment of most brain metastases. Several new therapies, with a good penetration through the blood brain barrier, such as temozolomide, have been used in brain metastases with different results depending on the histology of the primary tumor. A better understanding of the complex processes underlying the development of brain metastasis will enable us to develop more satisfactory targeted treatments.

CNS Metastases in Breast Cancer

As systemic therapy of metastatic breast cancer improves, CNS involvement is becoming a more widespread problem. This article summarizes the current knowledge regarding the incidence, clinical presentation, diagnosis, prognosis, and treatment of CNS metastases in patients with breast cancer. When available, studies specific to breast cancer are presented; in studies in which many solid tumors were evaluated together, the proportion of patients with breast cancer is noted. On the basis of data from randomized trials and retrospective series, neurosurgery and stereotactic radiosurgery (SRS) may prolong survival in patients with single brain metastases. The treatment of multiple metastases remains controversial, as does the routine use of whole-brain radiotherapy (WBRT) after either surgery or SRS. Although it is widely assumed that chemotherapy is of limited benefit, data from case series and case reports suggest otherwise. WBRT, neurosurgery, SRS, and medical therapy each have a role in the treatment of CNS metastases; however, neurologic symptoms frequently are not fully reversible, even with appropriate therapy. Studies specifically targeted toward this group of patients are needed.

Brain metastases from breast cancer: identification of a high-risk group

AIMS

Brain metastases from breast cancer are an uncommon initial presentation of metastatic breast cancer, but brain metastases commonly occur later in women's metastatic illness. The aims of this study were to document the type, frequency, and temporal occurrence of brain metastases from breast cancer as well as the survival of women with such metastases, and to attempt to identify a subgroup of women at high risk of brain metastases who may benefit from pre-emptive medical intervention.

MATERIALS AND METHODS

The radiological reports of all women presenting with metastases aged under 70 years who had subsequently died were examined. The type, frequency, temporal occurrence and survival with brain metastases were documented. Correlations were sought between the frequency of brain metastases and age at metastatic presentation, tumour grade, histological type and oestrogen receptor (ER) status.

RESULTS

Of 219 patients who had died with metastatic disease and who were under 70 years of age at metastatic presentation, 49 (22%) developed brain metastases. The development of brain metastases was related to young age (P = 0.0002), with 43% of women under 40 years developing brain metastases. Brain metastases were more common in women whose tumours were ER negative (38%) compared with women with ER-positive disease (14%) (P = 0.0003). By combining age and ER status, it is possible to identify a group of women (age under 50 years and ER negative) with a 53% risk of developing brain metastases. This group included many women who had chemotherapy for visceral metastases, and 68% had either stable disease or disease response at other sites at the time of brain metastases presentation.

CONCLUSION

It is possible to identify a subgroup of women with metastatic breast cancer at high risk of brain metastases who may benefit from pre-emptive medical intervention, such as screening or prophylactic treatment.

Brain metastases

Brain metastases are one of the most feared complications of cancer because even small tumors may cause incapacitating neurologic symptoms. This article reviews the epidemiology, clinical features, treatment, and prognosis of brain metastases from system malignancies.

Capecitabine for 5-fluorouracil-resistant brain metastases from breast cancer

We report a case in which brain metastases originating from breast cancer responded to treatment with oral capecitabine. The metastases had progressed and Karnofsky performance status deteriorated despite whole brain irradiation, hormonal treatment, and systemic chemotherapy that included 5-fluorouracil (5-FU). In contrast, 2 months of treatment with oral capecitabine produced a partial response, documented by lesion size on magnetic resonance imaging and an improvement in performance status; both measures continued to improve during 11 months of capecitabine treatment.

Brain metastases

Brain metastases are an increasingly common complication in patients with systemic cancer. The optimal treatment for each patient depends on careful evaluation of several factors: the location, size, and number of brain metastases; the patient's age, general condition, and neurologic status; and the extent of systemic cancer to name a few. For patients with a single brain metastasis and limited systemic disease, the standard treatment is surgical resection followed by whole brain radiation therapy. In patients with a small, single metastasis, stereotactic radiosurgery is probably comparable to surgery. Patients with several metastases (up to three) and controlled systemic disease can be treated with whole-brain radiation and stereotactic radiosurgery. Patients with multiple metastases (more than three) are generally treated with whole-brain radiation alone. Radiosurgery is effective in treating patients with a limited number of recurrent brain metastases and stable systemic diseases. Surgery may have a role in patients with a large symptomatic recurrent lesion producing mass effect. Reirradiation and chemotherapy may have a limited role in patients with multiple recurrent metastases.

[Brain metastases and chemotherapy]

INTRODUCTION

The epidemiology of brain or central nervous system metastases is poorly documented. Retrospective studies based on autopsies that were aimed at investigating the incidence and prevalence of brain metastases have revealed the shortfalls in tumour registers. The exact role of cerebral metastases has not been addressed within the scope of cancer considered as a public health issue.

CURRENT KNOWLEDGE AND KEY POINTS

The prognosis of brain metastases should not be considered either on general or a priori basis as being poorer than that of other metastatic sites. Evaluation of the role of focal radiation therapy and chemotherapy is still in progress. Appropriate use of therapeutical strategies directed at brain tumors generally improves the condition of most patients. It also usually increases survival and enhances the quality of life.

FUTURE PROSPECTS AND PROJECTS

The role of chemotherapy in current therapeutical strategies has not yet been defined and should be investigated and developed.

Ten years disease-free survival after solitary brain metastasis from breast cancer

The unique case of a 51-year-old woman who developed a solitary brain metastasis as the first site of systemic disease 11 months after a total mastectomy for an undifferentiated infiltrating ductal carcinoma of her right breast is described. After surgery for the pT2pN0 carcinoma, the patient received radiotherapy of the internal mammary and supraclavicular lymph nodes. The brain metastasis was treated with surgery and adjuvant whole-brain radiotherapy to a total dose of 30 Gy in December 1984 and January 1985. Afterwards a hormonal treatment with tamoxifen was initiated, which still continues. Since then no further distant or lymph node metastases have developed. The patient is under regular after-care and undergoes various apparative examinations every 6 months. She is generally well and suffers only from a postoperatively persistent hemianopsia. This is the first case in which a disease-free survival for more than 10 years after brain metastases from breast cancer has been reported. It illustrates the specific biological behaviour of this tumour type and the chance of achieving long-term survival in very selected cases.

Central nervous system metastasis in breast cancer

BACKGROUND AND PURPOSE

Central nervous system (CNS) metastasis occurs in at least 30% of patients with breast cancer. Standard treatment is the same as in other solid tumors, though clinical behavior, and sensitivity to radiation therapy (RT) and to chemotherapy may differ considerably. Most of these patients die within a few months, but a substantial subgroup may survive a year or more. The last decade has given rise to new diagnostic methods, new surgical and radiotherapeutic techniques, and the clinical evidence of a chemotherapy permissive blood-brain barrier in CNS metastases. The literature was reviewed to assess the clinical impact of early diagnosis, recognition of prognostic factors, and of the recently developed therapeutic approaches.

MATERIAL AND METHODS

Review of the literature on CNS involvement in breast cancer focusing on clinical studies on early diagnosis, new modes of treatment, and factors influencing outcome.

RESULTS

Although randomized studies are still awaited, systemic chemotherapy seems a valuable alternative for RT of brain metastases in selected cases. In meningeal carcinomatosis, long survival may be independent of intraventricular chemotherapy. Neurotoxicity of intensive intraventricular treatment is considerable. In epidural metastasis, early diagnosis with prompt start of treatment remains the crucial factor for outcome. Radiation therapy is the mainstay of treatment of epidural metastasis, but new surgical techniques and even systemic chemotherapy should be considered in selected cases.

CONCLUSIONS

Recognition of prognostic factors combined with appropriate use of various recently developed therapeutic possibilities will improve the clinical outcome including better local tumor control and less treatment-induced neurotoxicity in a considerable number of patients with CNS metastasis from breast cancer.

Response of brain metastases from breast cancer to megestrol acetate: a case report

A 56 year old women was treated with megestrol acetate (Megace) 40 mg p.o. q.i.d. for her cerebellar metastasis of primary adenocarcinoma of the breast. She had previously undergone two surgical resections of her brain metastasis, and a course of radiotherapy. After failing to tolerate tamoxifen therapy, she received Megace, with marked improvement in her cerebellar tumor on CT scans. Despite good control of her brain tumor with Megace, she developed progressive neurological symptoms thought to be due to meningeal carcinomatosis, and died two years after initiating Megace therapy. We conclude that Megace could potentially be beneficial in some patients with brain metastases from adenocarcinoma of the breast.