Prevention of Brain Metastases: A New Frontier

This review discusses the topic of prevention of brain metastases from the most frequent solid tumor types, i.e., lung cancer, breast cancer and melanoma. Within each tumor type, the risk of brain metastasis is related to disease status and molecular subtype (i.e., EGFR-mutant non-small cell lung cancer, HER2-positive and triple-negative breast cancer, BRAF and NRAF-mutant melanoma). Prophylactic cranial irradiation is the standard of care in patients in small cell lung cancer responsive to chemotherapy but at the price of late neurocognitive decline. More recently, several molecular agents with the capability to target molecular alterations driving tumor growth have proven as effective in the prevention of secondary relapse into the brain in clinical trials. This is the case for EGFR-mutant or ALK-rearranged non-small cell lung cancer inhibitors, tucatinib and trastuzumab-deruxtecan for HER2-positive breast cancer and BRAF inhibitors for melanoma. The need for screening with an MRI in asymptomatic patients at risk of brain metastases is emphasized.

HER2-Positive Metastatic Breast Cancer: Available Treatments and Current Developments

For several years, the overexpression of the HER2 receptor in breast cancer has been correlated with a poor prognosis and an increased risk of developing brain metastases. Currently, the combination of anti-HER2 double blockade and taxane and trastuzumab emtansine (T-DM1) are considered the standard treatments for metastatic breast cancer overexpressing these receptors in the first and second line. Very recently, the development of a new antidrug conjugate, trastuzumab–deruxtecan, has improved the overall survival of patients, even in second-line treatment. However, trastuzumab–deruxtecan has become a new standard. Despite the benefits of these antidrug conjugates, this benefit in patients with brain metastases remains unclear. Tucatinib is a new tyrosine kinase inhibitor that has given hope for the treatment of these patients. The objective of this article was to review data on the established drugs and novel agents for HER2-positive MBC and to discuss how to incorporate anti-HER2 therapies in first and later-line settings.

Phase II study to investigate the efficacy of trastuzumab biosimilar (Herzuma®) plus treatment of physician's choice (TPC) in patients with heavily pretreated HER-2+ metastatic breast cancer (KCSG BR 18–14/KM10B)

We investigated the efficacy and safety of a trastuzumab biosimilar, Herzuma®, in combination with treatment of physician's choice (TPC) in patients with HER2+ metastatic breast cancer (MBC) who had failed at least two HER2 directed chemotherapies.

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Treatment of HER2-positive breast cancer is rapidly evolving with the development of new agents. However, treatment options are still limited after progression with proven anti-HER2 therapies.

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The combination of chemotherapy with a trastuzumab biosimilar, Herzuma®, was effective and safe in patients with heavily pre-treated HER2+ MBC.

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Duration of response to previous anti-HER2 therapy, PIK3CA and ERBB2 mutations were associated with clinical efficacies of trastuzumab biosimilar plus chemotherapy.

A SNAI2-PEAK1-INHBA stromal axis drives progression and lapatinib resistance in HER2-positive breast cancer by supporting subpopulations of tumor cells positive for antiapoptotic and stress signaling markers

Intercellular mechanisms by which the stromal microenvironment contributes to solid tumor progression and targeted therapy resistance remain poorly understood, presenting significant clinical hurdles. PEAK1 (Pseudopodium-Enriched Atypical Kinase One) is an actin cytoskeleton- and focal adhesion-associated pseudokinase that promotes cell state plasticity and cancer metastasis by mediating growth factor-integrin signaling crosstalk. Here, we determined that stromal PEAK1 expression predicts poor outcomes in HER2-positive breast cancers high in SNAI2 expression and enriched for MSC content. Specifically, we identified that the fibroblastic stroma in HER2-positive breast cancer patient tissue stains positive for both nuclear SNAI2 and cytoplasmic PEAK1. Furthermore, mesenchymal stem cells (MSCs) and cancer-associated fibroblasts (CAFs) express high PEAK1 protein levels and potentiate tumorigenesis, lapatinib resistance and metastasis of HER2-positive breast cancer cells in a PEAK1-dependent manner. Analysis of PEAK1-dependent secreted factors from MSCs revealed INHBA/activin-A as a necessary factor in the conditioned media of PEAK1-expressing MSCs that promotes lapatinib resistance. Single-cell CycIF analysis of MSC-breast cancer cell co-cultures identified enrichment of p-Akthigh/p-gH2AXlow, MCL1high/p-gH2AXlow and GRP78high/VIMhigh breast cancer cell subpopulations by the presence of PEAK1-expressing MSCs and lapatinib treatment. Bioinformatic analyses on a PEAK1-centric stroma-tumor cell gene set and follow-up immunostaining of co-cultures predict targeting antiapoptotic and stress pathways as a means to improve targeted therapy responses and patient outcomes in HER2-positive breast cancer and other stroma-rich malignancies. These data provide the first evidence that PEAK1 promotes tumorigenic phenotypes through a previously unrecognized SNAI2-PEAK1-INHBA stromal cell axis.

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.

Incidence of Brain Metastases in Nonmetastatic and Metastatic Breast Cancer: Is There a Role for Screening?

BACKGROUND

Current National Comprehensive Cancer Network and American Society of Clinical Oncology guidelines recommend against screening breast cancer patients for asymptomatic brain metastases. Because brain metastases are a major cause of morbidity and mortality from breast cancer, we undertook a literature review to ascertain whether there might be a role for brain metastases screening in high-risk patient subgroups.

MATERIALS AND METHODS

A literature search was conducted on the OvidSP platform in the MedLine database, using MeSH terms and subject headings related to breast cancer, brain metastases, and incidence. The search was conducted without language or publication restrictions, and included articles indexed from January 1, 2006 to June 10, 2018. Experimental and observational studies that reported the incidence of brain metastases in patients with nonmetastatic or metastatic breast cancer were included.

RESULTS

One hundred seventy studies were identified, with 33 included in the final analysis. Among nonmetastatic breast cancer patients, incidence of brain metastases as site of first recurrence per year of median follow-up ranged from 0.1% to 3.2%. Although incidence of brain metastases was much higher among the metastatic breast cancer population overall, it was particularly high among metastatic HER2-overexpressing (HER2⁺) and triple-negative populations, ranging between 22% and 36% for the former, and 15%-37% for the latter in the absence of screening.

CONCLUSION

In patients with nonmetastatic breast cancer, screening for asymptomatic brain metastases cannot currently be justified. However, due to the high incidence of brain metastases among patients with metastatic HER2⁺ and triple-negative breast cancer, studies to determine the value of screening for brain metastases should be undertaken in these subgroups.

HER2 positive bilateral metachronous primary breast carcinoma: A case report

Human epidermal growth factor receptor 2 (HER2) positive is a unique molecular subtype of breast cancer (BC) characterized by high malignancy and poor prognosis. Bilateral primary breast cancer (BPBC) harboring HER2 gene amplification is available to be detected among the BC survivors due to the increasing use of anti-HER2 adjuvant therapy. However, owing to the paucity of cases reported, knowledge of treating HER2-positive BPBC patients including the clinical behavior, histopathologic characteristics, anti-HER2 therapeutic response and disease outcome are not fully understood. Here we report a case of its kind receiving nonstandardized treatment during adjuvant stage. Upon tumor recurrence with liver metastasis, she received trastuzumab combined with chemotherapy and reached a PFS of 14.5 months in first-line treatment. While maintained trastuzumab plus carboplatin as second-line treatment progressed promptly, re-treatment of trastuzumab after lapatinib administration in third line can still benefit the patient. The present case report delineates an anti-HER2 path for a particular characterized patient, and also provides new evidence of trastuzumab re-usage after disease progression of prior anti-HER2 therapy.

Systemic Treatment Options for HER2-Positive Breast Cancer Patients with Brain Metastases beyond Trastuzumab: A Literature Review

BACKGROUND

The incidence of brain metastases (BM) in breast cancer patients has increased. Many retrospective analyses have shown that first-line treatment with trastuzumab prolongs survival in patients with HER2-positive BM. In contrast, the evidence for other therapies targeting HER2 for patients with BM is rare.

METHODS

The aim of this review is to update the reader about current systemic treatment options in patients with HER2-positive metastatic breast cancer with BM who had already received trastuzumab. A literature search was performed in the PubMed database in June 2016. 30 relevant reports concerning the efficacy of trastuzumab emtansine (T-DM1), lapatinib and its combination with other cytotoxic agents, pertuzumab and novel HER2-targeting substances were identified.

RESULTS

There is limited but promising evidence for the use of T-DM1 and pertuzumab in the treatment of BM. Up to now, most reported studies used lapatinib as treatment of HER2-positive breast cancer with BM, a treatment with only a modest effect and a high toxicity profile. The combination of lapatinib with cytotoxic agents seems to result in better response rates.

CONCLUSION

Further prospective investigations are needed to investigate the efficacy of the established and novel HER2-targeting agents on BM in HER2-positive breast cancer patients.

Targeted Therapies in HER2-Overexpressing Metastatic Breast Cancer

Human epidermal growth factor receptor-2 (HER2) is amplified in 25-30% of breast cancers and is associated with aggressive disease and poorer survival. Multiple anti-HER2 targeted therapies have dramatically changed management and outcome of this subgroup, both in adjuvant and metastatic settings. Despite the improvement of survival thanks to trastuzumab, unclear mechanisms of resistance occur, which has led to the development of new anti-HER2 therapies such as lapatinib, pertuzumab, and trastuzumab emtansine (T-DM1). The optimal sequence of the available drugs is still not well established. All this progress raises the question of toxicity that need to be managed, especially with longer survival of patients. In this article, we review different anti-HER2 therapies used in HER2-positive m etastatic breast cancer.

Durable Clinical Benefit of Pertuzumab in a Young Patient with BRCA2 Mutation and HER2-Overexpressing Breast Cancer Involving the Brain

Patients with HER2-positive breast cancer and brain metastases have limited treatment options, and, as a result of their poor performance status and worse prognosis, they are underrepresented in clinical trials. Not surprisingly, these patients may not be fit enough to receive any active treatment and are offered supportive therapy. BRCA2 mutations are reported to be rarely associated with HER2-overexpressing advanced breast cancer and even more rarely with brain metastases at diagnosis. We report on a BRCA2-positive breast cancer patient with metastatic disease in multiple sites, including the brain, and poor performance status who exhibited an extraordinary clinical and imaging response to the novel anti-HER2 therapy pertuzumab after multiple lines of therapy including anti-HER2 targeting. To our knowledge, the clinicopathologic and therapeutic characteristics of this patient point to a unique case and an urgent need for further investigation of pertuzumab in patients with brain metastases.

Brain metastasis in breast cancer: a comprehensive literature review

This comprehensive review provides information on epidemiology, size, grade, cerebral localization, clinical symptoms, treatments, and factors associated with longer survival in 14,599 patients with brain metastasis from breast cancer; the molecular features of breast cancers most likely to develop brain metastases and the potential use of these predictive molecular alterations for patient management and future therapeutic targets are also addressed. The review covers the data from 106 articles representing this subject in the era of modern neuroimaging (past 35 years). The incidence of brain metastasis from breast cancer (24 % in this review) is increasing due to advances in both imaging technologies leading to earlier detection of the brain metastases and introduction of novel therapies resulting in longer survival from the primary breast cancer. The mean age at the time of breast cancer and brain metastasis diagnoses was 50.3 and 48.8 years respectively. Axillary node metastasis was noted in 32.8 % of the patients who developed brain metastasis. The median time intervals between the diagnosis of breast cancer to identification of brain metastasis and from identification of brain metastasis to death were 34 and 15 months, respectively. The most common symptoms experienced in patients with brain metastasis consisted of headache (35 %), vomiting (26 %), nausea (23 %), hemiparesis (22 %), visual changes (13 %) and seizures (12 %). A majority of the patients had multiple metastases (54.2 %). Cerebellum and frontal lobes were the most common sites of metastasis (33 and 16 %, respectively). Of the primary tumors for which biomarkers were recorded, 37 % were estrogen receptor (ER)+, 41 % ER-, 36 % progesterone receptor (PR)+, 34 % PR-, 35 % human epithelial growth factor receptor 2 (HER2)+, 41 % HER2-, 27 % triple negative and 18 % triple positive (TP). Treatment in most patients consisted of a multimodality approach often with two or more of the following: whole brain radiation therapy (52 %), chemotherapy (51 %), stereotactic radiosurgery (20 %), surgical resection (14 %), trastuzumab (39 %) for HER2 positive tumors, and hormonal therapy (34 %) for ER and/or PR positive tumors. Factors that had an impact on prognosis included grade and size of the tumor, multiple metastases, presence of extra-cranial metastasis, triple negative or HER2+ biomarker status, and high Karnovsky score. Novel therapies such as application of agents to reduce tumor angiogenesis or alter permeability of the blood brain barrier are being explored with preliminary results suggesting a potential to improve survival after brain metastasis. Other potential therapies based on genetic alterations in the tumor and the microenvironment in the brain are being investigated; these are briefly discussed.

Anti-HER2 Therapy Beyond Second-Line for HER2-Positive Metastatic Breast Cancer: A Short Review and Recommendations for Several Clinical Scenarios from a Spanish Expert Panel

BACKGROUND

The aim of this project was to provide an expert opinion regarding anti-human epidermal growth factor receptor 2 (HER2) therapy beyond second-line treatment of metastatic breast cancer (mBC).

METHODS

A group of experts discussed specific issues concerning anti-HER2 therapy in late-line settings in mBC.

RESULTS

Trastuzumab emtansine (T-DM1) or dual HER2 blockade appeared to be good options for HER2-positive mBC after ≥ 2 HER2-targeted therapies. Once an objective response has been achieved with anti-HER2-containing therapy, the anti-HER2 agent can be continued until progression of the disease, unacceptable toxicity or patient decision. mBC treated with ≥ 3 consecutive lines of anti-HER therapy, ≥ 1 being a dual HER2 blockade and with early progression of disease during a fourth or later-line treatment, are clinically resistant to anti-HER therapy. For progression of metastasis in the brain after anti-HER2 therapy, lapatinib and chemotherapy appear to be a good alternative after best local treatment.

CONCLUSIONS

Further clinical trials are needed to provide valuable knowledge about the best treatment options in the later settings of mBC.

Trastuzumab-based Retreatment after Lapatinib in Heavily Pretreated HER2 Positive Metastatic Breast Cancer: an Anatolian Society of Medical Oncology Study

BACKGROUND

For HER2 positive metastatic breast cancer (MBC), continuing anti-HER2 therapy beyond progression is associated with improved outcome. However retreatment with trastuzumab after lapatinib progression is controversial. We retrospectively analyzed the efficacy of trastuzumab-based chemotherapy in HER2+ metastatic breast cancer patients whose disease progressed after lapatinib.

MATERIALS AND METHODS

Between October 2010 and May 2013, 54 patients whose disease progressed after lapatinib were retreated with trastuzumab-based chemotherapy. Efficacy and toxicity results were evaluated retrospectively.

RESULTS

The median age of patients was 46 (range 27-67). Fourteen patients (26%) had metastases at the time of diagnosis. All of the patients had received trastuzumab in an adjuvant or metastatic setting, while 16 (30%) had received two lines of trastuzumab. All patients had received lapatinib plus capecitabine. The median chemotherapy line for the metastatic setting was 2 (range 1-7). Cranial metastases were identified in 27 (50%) patients. 53 patients received trastuzumab-based chemotherapy following lapatinib progression while one patient received trastuzumab monotherapy. Combination chemotherapy consisted of navelbin (n=33), taxane (n=10), gemcitabine (n=2), platinum (n=2) and platinum with taxane (n=6). The median treatment cycle was 5 (range 1-44). Among 49 patients assessed for response 2 (4%) showed CR, 12 (25%) PR, 11 (22%) SD and 24 (49%) disease progression. Asymptomatic cardiotoxicity was reported in 2 (4%) of the patients. At a median follow-up of 9 months (1-39), median progression-free survival was 5 months (95% CI 4.1-5.9) and median overall survival was 10 months (95% CI 6.9-13.0). PFS and OS were not affected by the absence/presence of cranial metastases.

CONCLUSIONS

Retreatment with trastuzumab-based therapy after lapatinib progression showed efficacy in heavily treated MBC patients.

Targeting HER2 Positive Breast Cancer with Chemopreventive Agents

Human epidermal growth factor receptor 2-positive (HER2+) breast cancer is a subtype of breast cancer that is exhibited in approximately 20-30% of breast cancer cases. The overexpression of HER2 is typically associated with a more aggressive disease and poor prognosis. Currently, the therapeutic drugs trastuzumab and lapatinib are the most commonly used to combat HER2+ breast cancer. However, tumors can develop resistance to these drugs. A better understanding of the mechanism of how HER2+ breast cancer works will help aid the development for new therapeutic approaches which more closely target the source of the signaling dysfunction. This review summarizes four major points in the context of HER2 over-expressing breast cancer (i) HER2 as a molecular target in breast cancer therapy, (ii) current treatment options as well as ongoing clinical studies, (iii) animal and cellular models for the study of HER2 over-expressing breast cancer, and (iv) future therapies and chemopreventive agents used to target HER2+ breast cancer.

HER2-directed therapy: current treatment options for HER2-positive breast cancer

Over the past decade, the management of HER2-positive breast cancer has evolved dramatically. In addition to advances in screening, genetic testing, imaging, surgical and radiation techniques, innovations in medical therapy including widespread use of HER2-directed therapy in early and advanced breast cancer have revolutionized breast cancer care and changed the natural history of HER2-positive breast cancer. A substantial number of HER2-targeted agents are being developed including monoclonal antibodies, small molecule inhibitors, and antibody drug conjugates. Trastuzumab is the prototype HER2-directed therapy that was introduced in the late 1990s for the management of metastatic breast cancer and later showed efficacy in early stage disease. Despite the practice changing impact of trastuzumab and improvement in outcomes of women with HER2-positive breast cancer resistance to trrastuzumab is a major clinical issue, occurring in both early stage and advanced disease, and new treatment strategies are clearly required. Combining HER2-targeted agents and dual HER2 blockade has been successful in early and advanced breast cancer. Furthermore, selected delivery of potent chemotherapeutic agent coupled with HER2 inhibition promises new treatment options. This review is focused on current HER2-directed treatments for women with HER2-positive breast cancer including monoclonal antibodies, small molecule inhibitors, and antibody drug conjugates.

Effect of adjuvant/neoadjuvant trastuzumab on clinical outcomes in patients with HER2-positive metastatic breast cancer

BACKGROUND

The purpose of the current study was to describe the outcomes of patients with human epidermal growth factor receptor 2 (HER2)-overexpressed/amplified (HER2+) early breast cancer who received adjuvant or neoadjuvant trastuzumab-based therapy and were subsequently retreated with trastuzumab for metastatic disease.

METHODS

A total of 353 patients with metastatic HER2+ breast cancer who were treated with trastuzumab as part of their first-line treatment for metastatic disease were identified. A total of 75 patients had received adjuvant or neoadjuvant trastuzumab-based therapy for early breast cancer, and 278 had not. Clinical outcomes of patients who had or had not received prior trastuzumab were compared using Cox proportional hazards regression and logistic regression analyses. Survival was estimated using the Kaplan-Meier method.

RESULTS

The clinical benefit (complete response, partial response, or stable disease of ≥ 6 months) rates were 71% in the group who did not receive prior trastuzumab and 39% in the group previously treated with trastuzumab. The adjusted odds ratios were 0.28 (95% confidence interval [95% CI], 0.13-0.59; P = .0009) for clinical benefit rates and 0.39 (95% CI, 0.18-0.82; P = .038) for objective (complete or partial) response rates. In the univariate analysis, the median overall survival rate was longer in the group who did not receive prior trastuzumab (36 months vs 28 months) (hazards ratio, 1.47; 95% CI, 1.07-2.01 [P = .022]). The multivariate analysis found no significant difference in overall survival.

CONCLUSIONS

When treated with trastuzumab for metastatic disease, patients with HER2+ breast cancer without prior exposure to trastuzumab were found to have superior clinical outcomes to those with prior exposure. Prior trastuzumab exposure should be considered in treatment algorithms and in HER2-targeted clinical trial enrollment for metastatic disease.

Trastuzumab emtansine versus treatment of physician's choice for pretreated HER2-positive advanced breast cancer (TH3RESA): a randomised, open-label, phase 3 trial

BACKGROUND

Patients with progressive disease after two or more HER2-directed regimens for recurrent or metastatic breast cancer have few effective therapeutic options. We aimed to compare trastuzumab emtansine, an antibody-drug conjugate comprising the cytotoxic agent DM1 linked to trastuzumab, with treatment of physician's choice in this population of patients.

METHODS

This randomised, open-label, phase 3 trial took place in medical centres in 22 countries across Europe, North America, South America, and Asia-Pacific. Eligible patients (≥18 years, left ventricular ejection fraction ≥50%, Eastern Cooperative Oncology Group performance status 0-2) with progressive HER2-positive advanced breast cancer who had received two or more HER2-directed regimens in the advanced setting, including trastuzumab and lapatinib, and previous taxane therapy in any setting, were randomly assigned (in a 2:1 ratio) to trastuzumab emtansine (3·6 mg/kg intravenously every 21 days) or physician's choice using a permuted block randomisation scheme by an interactive voice and web response system. Patients were stratified according to world region (USA vs western Europe vs other), number of previous regimens (excluding single-agent hormonal therapy) for the treatment of advanced disease (two to three vs more than three), and presence of visceral disease (any vs none). Coprimary endpoints were investigator-assessed progression-free survival (PFS) and overall survival in the intention-to-treat population. We report the final PFS analysis and the first interim overall survival analysis. This study is registered with ClinicalTrials.gov, number NCT01419197.

FINDINGS

From Sept 14, 2011, to Nov 19, 2012, 602 patients were randomly assigned (404 to trastuzumab emtansine and 198 to physician's choice). At data cutoff (Feb 11, 2013), 44 patients assigned to physician's choice had crossed over to trastuzumab emtansine. After a median follow-up of 7·2 months (IQR 5·0-10·1 months) in the trastuzumab emtansine group and 6·5 months (IQR 4·1-9·7) in the physician's choice group, 219 (54%) patients in the trastuzumab emtansine group and 129 (65%) of patients in the physician's choice group had PFS events. PFS was significantly improved with trastuzumab emtansine compared with physician's choice (median 6·2 months [95% CI 5·59-6·87] vs 3·3 months [2·89-4·14]; stratified hazard ratio [HR] 0·528 [0·422-0·661]; p<0·0001). Interim overall survival analysis showed a trend favouring trastuzumab emtansine (stratified HR 0·552 [95% CI 0·369-0·826]; p=0·0034), but the stopping boundary was not crossed. A lower incidence of grade 3 or worse adverse events was reported with trastuzumab emtansine than with physician's choice (130 events [32%] in 403 patients vs 80 events [43%] in 184 patients). Neutropenia (ten [2%] vs 29 [16%]), diarrhoea (three [<1%] vs eight [4%]), and febrile neutropenia (one [<1%] vs seven [4%]) were grade 3 or worse adverse events that were more common in the physician's choice group than in the trastuzumab emtansine group. Thrombocytopenia (19 [5%] vs three [2%]) was the grade 3 or worse adverse event that was more common in the trastuzumab emtansine group. 74 (18%) patients in the trastuzumab emtansine group and 38 (21%) in the physician's choice group reported a serious adverse event.

INTERPRETATION

Trastuzumab emtansine should be considered as a new standard for patients with HER2-positive advanced breast cancer who have previously received trastuzumab and lapatinib.

FUNDING

Genentech.

Clinical outcomes and cardiac safety of continuous antiHer2 therapy in c-erbB2-positive metastatic breast cancer patients

BACKGROUND

To explore clinical outcomes and cardiac safety of continuous antiHer2 therapy.

PATIENTS AND METHODS

This retrospective study evaluates overall survival (OS), time to treatment failure (TTF), and cardiac safety of 80 consecutive Her2-positive metastatic breast cancer (MBC) patients that received ≥ 12 months of therapy with trastuzumab, followed by lapatinib-based or trastuzumab-based therapy.

RESULTS

All patients received trastuzumab as first antiHer2 therapy; 54% received lapatinib in the second or subsequent line. Median OS was 34 months (12-120 months). Median OS was 48 months in the subgroup of 43 patients who received lapatinib and 26 months in the 37 patients who did not. Median TTF was shorter for lapatinib. There were three cardiac events and trastuzumab-based chemotherapy (CT) was interrupted in one patient because left ventricular ejection fraction (LVEF) decreased to ≤ 40%.

CONCLUSION

Continuous antiHer2 therapy provides good clinical outcomes, especially in those patients who received lapatinib. Cardiac dysfunction was a rare event, reversible, associated to trastuzumab and not related to treatment duration.

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.

Advances in first-line treatment for patients with HER-2+ metastatic breast cancer

BACKGROUND

The prognosis for breast cancer patients overexpressing human epidermal growth factor receptor (HER)-2 has changed with anti-HER-2-targeted therapy. Although anti-HER-2 therapy with trastuzumab and chemotherapy is the standard first-line treatment, the best therapeutic regimen has yet to be defined, and new strategies are evolving.

METHODS

A literature review of well-established and recently published trials, reviews, and ongoing clinical trials addressing first-line treatment for HER-2(+) metastatic breast cancer patients was performed.

RESULTS

Taxanes are the agents most commonly used in combination with trastuzumab, but other chemotherapy drugs, such as anthracyclines, vinorelbine, and gemcitabine and triple-combination therapies including platinum compounds, capecitabine, and taxanes have been studied. The combination of aromatase inhibitors with anti-HER-2 therapies is a new therapeutic option for some patients who coexpress HER-2 and hormone receptors, although its activity observed in randomized clinical trials seems to be inferior to that of chemotherapy plus anti-HER-2 therapies. In addition, new anti-HER-2 therapies have shown activity in HER-2(+) tumors, both alone and in combination with trastuzumab.

CONCLUSIONS

Trastuzumab plus chemotherapy is the current standard of care for the upfront treatment of HER-2(+) breast cancer patients, though other anti-HER-2-targeting agents may appear as new standards in the upcoming years.

Acute myeloblastic leukemia in patients with multiple myeloma

Background

The continuum of anti-HER2 agents is a standard treatment of HER2 + metastatic breast cancer (MBC). This study evaluated the efficacy of lapatinib plus vinorelbine in patients progressed on both trastuzumab and lapatinib treatments.

Methods

A total of 149 patients were randomly assigned to lapatinib with vinorelbine (LV) (n = 75; lapatinib, 1000 mg daily; vinorelbine 20 mg/m² D1, D8 q3w) or vinorelbine (V) (n = 74; 30 mg/m² D1, D8 q3w). The primary endpoint was progression-free survival (PFS) rate at 18 weeks.

Results

The median number of previous anti-HER2 therapies was 2 (range 2–5). There was no significant difference in PFS rate at 18 weeks between LV and V arms (45.9% vs 38.9%, p = 0.40). ORR was 19.7% in LV arm, and 16.9% in V arm (p = 0.88). PFS and OS did not differ between two arms (LV vs V; median PFS, 16 vs 12 weeks, HR = 0.86, 95% CI 0.61–1.22; median OS, 15.0 vs 18.9 months, HR = 1.07, 95% CI 0.72–1.58). Toxicity profiles were similar in both arms and all were manageable.

Conclusions

Lapatinib plus vinorelbine treatment was tolerable; however, it failed to demonstrate the clinical benefits over vinorelbine alone in patients with HER2 + MBC after progression on both trastuzumab and lapatinib.

Clinical trial registration

ClinicalTrials.gov number NCT01730677.