Central nervous system progression among patients with metastatic breast cancer responding to trastuzumab treatment

Central nervous system (CNS) metastases from breast cancer are common and can present as the first or solitary site of disease progression. The CNS has been reported to act as a sanctuary site that denies access to many chemotherapeutic agents. We present here, a series of 10 metastatic breast cancer patients who developed CNS metastases after an initial response to trastuzumab treatment. Forty one patients with metastatic HER2-overexpressing breast cancer, without evidence of CNS involvement prior to the initiation of trastuzumab treatment, were followed during trastuzumab treatment. A neurological evaluation was performed in those patients who developed neurological signs or symptoms during the course of treatment. The clinical course and pattern of CNS involvement in these patients are discussed. Thirty two patients (78%) showed an initial response to trastuzumab treatment. Ten (31%) of the responding patients developed either isolated CNS relapse or concurrent CNS and systemic progression at a median of 43 weeks after the initiation of trastuzumab treatment. Trastuzumab as a single agent was continued following control of brain symptoms in three patients, two showed signs of systemic disease progression at 11 and 15 weeks following the diagnosis of CNS metastases, respectively. In two other patients, trastuzumab in combination with weekly chemotherapy was continued for more than 20 weeks after CNS relapse without evidence of disease progression. The incidence of CNS involvement in our group of patients was higher than expected. With more successful and prolonged systemic anti-tumour effects achieved by novel drug combinations, the risk of developing CNS metastases might be even greater. Evaluation of prophylactic cranial irradiation strategies might be studied for high-risk patients.     

Incidence, pattern and timing of brain metastases among patients with advanced breast cancer treated with trastuzumab

We aim to investigate the incidence, patterns and timing of brain metastases in advanced breast cancer patients who have previously received trastuzumab. Eighty-seven patients who had received trastuzumab for advanced breast cancer from November 1999 to September 2003 at the Royal Marsden Hospital were assessed. With a median follow-up period of 11 months from commencing trastuzumab, 23 patients developed brain metastases (30% at 1 year; 95% CI 58-82%). Among 57 patients who had clinical benefits on trastuzumab, 12 (21%) patients developed first disease progression in brain with 75% of them had isolated CNS progression. Moreover, among patients who received trastuzumab as first line treatment, isolated brain metastases were the initial site of progression in 17% patients. Nearly all patients developed parenchymal brain disease. This study shows brain metastases are common phenomenon in HER2 positive advanced breast cancer patients receiving trastuzumab and also may implicate the brain as a sanctuary site for early relapse in this patient cohort.     

Isolated central nervous system metastases in patients with HER2-overexpressing advanced breast cancer treated with first-line trastuzumab-based therapy.

PURPOSE: The aim of this study was to characterize the prevalence and predictors of central nervous system (CNS) metastasis among women with HER2-overexpressing metastatic breast cancer receiving trastuzumab-based therapy. METHODS: The frequency and time course of isolated CNS progression were characterized among women with HER2-positive metastatic breast cancer, receiving chemotherapy with or without trastuzumab as first-line treatment for metastatic disease in two clinical trials. The first trial was a multicenter randomized phase III study of chemotherapy (doxorubicin/cyclophosphamide or paclitaxel) +/- trastuzumab, and the second was a multicenter phase II trial of vinorelbine + trastuzumab. All patients had measurable disease and were free of symptomatic CNS disease at initiation of study treatment. RESULTS: Nearly 10% of patients receiving trastuzumab in combination with chemotherapy developed isolated CNS metastases as first site of tumor progression. Progression in the CNS tended to be a later event than progression at other sites among women receiving trastuzumab-based therapy. Trastuzumab-based treatment did not substantially delay onset of CNS metastases as initial site of progression. Following diagnosis with primary breast cancer, tumors with HER2 gene amplification tend to be associated with greater risk of isolated CNS progression compared with those lacking gene amplification. CONCLUSIONS: Patients with HER2-overexpressing metastatic breast cancer are at risk for isolated CNS progression, reflecting improved peripheral tumor control and patient survival through use of trastuzumab-based therapy, and a relative lack of CNS activity with trastuzumab. Clinicians should be aware of this association. Better treatments for CNS recurrences are needed.     

Central nervous system metastases in HER-2 positive metastatic breast cancer patients treated with trastuzumab: incidence, survival, and risk factors

BACKGROUND: A higher incidence of central nervous system (CNS) metastases in HER-2-positive metastatic breast cancer (MBC) has recently been reported. MATERIALS AND METHODS: Aims of this observational study were to evaluate the incidence of CNS metastases in HER-2-positive MBC patients, to define the outcome of patients with CNS metastases, and to identify the risk factors for CNS relapse. RESULTS: Between April 1999 and June 2005 we treated 122 consecutive HER-2-positive MBC patients with chemotherapy and trastuzumab. At a median follow-up of 28 months from the occurrence of metastatic disease, 43 patients (35.2%) developed CNS metastases. The median time to death from the diagnosis of CNS metastases was 23.46 months. At multivariate analysis we found that only premenopausal status at diagnosis of breast cancer and visceral metastases as the dominant site at relapse were significantly associated with a higher risk for CNS metastases. CONCLUSION: The CNS metastasis incidence is very high in HER-2-positive MBC, but the survival after CNS relapse in these patients is longer than in patients unselected for HER-2 status, because of the better control of extracranial disease obtained by trastuzumab. The identified risk factors for CNS relapse could allow us to select a subgroup of HER-2-positive MBC patients as candidates for active surveillance for CNS progression (by computed tomography or magnetic resonance imaging) and/or as candidates for accrual in trials of prevention of CNS relapse.     

Incidence of central nervous system metastases in patients with HER2-positive metastatic breast cancer treated with pertuzumab,trastuzumab, and docetaxel: results from the randomized phase III study CLEOPATRA

BackgroundResults from the phase III trial CLEOPATRA in human epidermal growth factor receptor 2-positive first-line metastatic breast cancer demonstrated significant improvements in progression-free and overall survival with pertuzumab, trastuzumab, and docetaxel over placebo, trastuzumab, and docetaxel. We carried out exploratory analyses of the incidence and time to development of central nervous system (CNS) metastases in patients from CLEOPATRA.Patients and methodsPatients received pertuzumab/placebo: 840 mg in cycle 1, then 420 mg; trastuzumab: 8 mg/kg in cycle 1, then 6 mg/kg; docetaxel: initiated at 75 mg/m². Study drugs were administered i.v. every 3 weeks. The log-rank test was used for between-arm comparisons of time to CNS metastases as first site of disease progression and overall survival in patients with CNS metastases as first site of disease progression. The Kaplan–Meier approach was used to estimate median time to CNS metastases as first site of disease progression and median overall survival.ResultsThe incidence of CNS metastases as first site of disease progression was similar between arms; placebo arm: 51 of 406 (12.6%), pertuzumab arm: 55 of 402 (13.7%). Median time to development of CNS metastases as first site of disease progression was 11.9 months in the placebo arm and 15.0 months in the pertuzumab arm; hazard ratio (HR) = 0.58, 95% confidence interval (CI) 0.39–0.85, P = 0.0049. Overall survival in patients who developed CNS metastases as first site of disease progression showed a trend in favor of pertuzumab, trastuzumab, and docetaxel; HR = 0.66, 95% CI 0.39–1.11. Median overall survival was 26.3 versus 34.4 months in the placebo and pertuzumab arms, respectively. Treatment comparison of the survival curves was not statistically significant for the log-rank test (P = 0.1139), but significant for the Wilcoxon test (P = 0.0449).ConclusionsWhile the incidence of CNS metastases was similar between arms, our results suggest that pertuzumab, trastuzumab, and docetaxel delays the onset of CNS disease compared with placebo, trastuzumab, and docetaxel.ClinicalTrials.govNCT00567190.     

Incidence and risk of central nervous system metastases as site of first recurrence in patients with HER2-positive breast cancer treated with adjuvant trastuzumab

BackgroundCentral nervous system (CNS) disease as the site of first relapse after exposure to adjuvant trastuzumab has been reported. We carried out comprehensive meta-analysis to determine the risk of CNS metastases as the first site of recurrence in patients with HER2-positive breast cancer who received adjuvant trastuzumab.MethodsEligible studies include randomized trials of adjuvant trastuzumab administered for 1 year to patients with HER2-positive breast cancer who reported CNS metastases as first site of disease recurrence. Statistical analyses were conducted to calculate the incidence, relative risk (RR), and 95% confidence intervals (CIs) using fixed-effects inverse variance and random-effects models.ResultsA total of 9020 patients were included. The incidence of CNS metastases as first site of disease recurrence in HER2-positive patients receiving adjuvant trastuzumab was 2.56% (95% CI 2.07% to 3.01%) compared with 1.94% (95% CI 1.54% to 2.38%) in HER2-positive patients who did not receive adjuvant trastuzumab. The RR of the CNS as first site of relapse in trastuzumab-treated patients was 1.35 (95% CI 1.02–1.78, P = 0.038) compared with control arms without trastuzumab therapy. The ratio of CNS metastases to total number of recurrence events was 16.94% (95% CI 10.85% to 24.07%) and 8.33% (95% CI 6.49% to 10.86%) for the trastuzumab-treated and control groups, respectively. No statistically significant differences were found based on trastuzumab schedule or median follow-up time. No evidence of publication bias was observed.ConclusionsAdjuvant trastuzumab is associated with a significant increased risk of CNS metastases as the site of first recurrence in HER2-positive breast cancer patients.     

Central nervous system metastases in women with HER-2 positive metastatic breast cancer after treatment with trastuzumab

Background: Historically, central nervous system (CNS) metastases have been reported to occur in 10–16% of women with metastatic breast cancer (MBC) with a median survival of less than 1 year after diagnosis of CNS disease. A higher rate of CNS metastases has been described in women with metastatic breast cancer (MBC) over‐expressing HER‐2 who receive trastuzumab therapy. Aims: The aim of this study was to examine the frequency of and potential risk factors for CNS metastases in these women. Our a priori hypotheses were that in MBC patients treated with trastuzumab, CNS metastases occurred (i) more frequently than historical controls, and (ii) in women with controlled systemic disease. Methods: A retrospective cohort study of 28 consecutive patients with MBC over‐expressing HER‐2 and treated with trastuzumab and chemotherapy was performed. Results: A total of 22/25 (88%) patients who initially responded to trastuzumab had progressed within a median of 11.2 months after starting trastuzumab therapy. Central nervous system metastases occurred in 11/28 (39%) patients and the remaining 11 patients had progressed elsewhere. At diagnosis of CNS metastases, 9/11 (82%) had controlled systemic disease (CR = 2, PR = 6, SD = 1). There were trends for patients with CNS metastases to have greater than one site of metastatic disease at the commencement of trastuzumab therapy (P = 0.06), and to be hormone receptor negative at initial diagnosis (P = 0.14). The median time to diagnosis of CNS metastases after the commencement of trastuzumab therapy was 12 months (range 6–19 months). The median survival after diagnosis of CNS metastases was 12 months (range 2–22 months). Conclusions: This study demonstrates a high rate of CNS metastases (39%) in HER‐2 positive MBC patients treated with trastuzumab. At CNS metastases most patients had controlled systemic disease and the median survival after CNS relapse was 1 year. We suggest aggressive management of CNS disease in this population. Additional strategies to decrease the incidence of CNS metastases in these patients may include prophylactic whole brain irradiation and the development of novel pharmacological agents with successful CNS penetration.     

Trastuzumab emtansine (T-DM1) versus lapatinib plus capecitabine in patients with HER2-positive metastatic breast cancer and central nervous system metastases: a retrospective,exploratory analysis in EMILIA

BackgroundWe characterized the incidence of central nervous system (CNS) metastases after treatment with trastuzumab emtansine (T-DM1) versus capecitabine–lapatinib (XL), and treatment efficacy among patients with pre-existing CNS metastases in the phase III EMILIA study.Patients and methodsIn EMILIA, patients with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer previously treated with trastuzumab and a taxane were randomized to T-DM1 or XL until disease progression. Patients with treated, asymptomatic CNS metastases at baseline and patients developing postbaseline CNS metastases were identified retrospectively by independent review; exploratory analyses were carried out.ResultsAmong 991 randomized patients (T-DM1 = 495; XL = 496), 95 (T-DM1 = 45; XL = 50) had CNS metastases at baseline. CNS progression occurred in 9 of 450 (2.0%) and 3 of 446 (0.7%) patients without CNS metastases at baseline in the T-DM1 and XL arms, respectively, and in 10 of 45 (22.2%) and 8 of 50 (16.0%) patients with CNS metastases at baseline. Among patients with CNS metastases at baseline, a significant improvement in overall survival (OS) was observed in the T-DM1 arm compared with the XL arm [hazard ratio (HR) = 0.38; P = 0.008; median, 26.8 versus 12.9 months]. Progression-free survival by independent review was similar in the two treatment arms (HR = 1.00; P = 1.000; median, 5.9 versus 5.7 months). Multivariate analyses demonstrated similar results. Grade ≥3 adverse events were reported in 48.8% and 63.3% of patients with CNS metastases at baseline administered T-DM1 and XL, respectively; no new safety signals were observed.ConclusionIn this retrospective, exploratory analysis, the rate of CNS progression in patients with HER2-positive advanced breast cancer was similar for T-DM1 and for XL, and higher overall in patients with CNS metastases at baseline compared with those without CNS metastases at baseline. In patients with treated, asymptomatic CNS metastases at baseline, T-DM1 was associated with significantly improved OS compared with XL.     

Defining prognosis for women with breast cancer and CNS metastases by HER2 status

BackgroundThe purpose of this retrospective study was to determine, in a cohort of patients with breast cancer and central nervous system (CNS) metastases, the effect of trastuzumab in patients with human epidermal growth factor receptor 2 (HER2)-positive disease and to compare this with that of patients with HER2-negative disease.MethodsFive hundred and ninety-eight patients with invasive breast cancer, CNS metastases and known HER2 status were identified. Time to CNS metastases and survival after CNS metastases were estimated by the Kaplan–Meier method, and Cox models were fitted to determine the association between HER2 status, trastuzumab treatment and outcomes after adjustment for other patient characteristics.ResultsIn the multivariable model, patients with HER2-negative disease [Hazard ratio (HR) 1.50, 95% confidence interval (CI) 1.15–1.95, P = 0.003] and patients with HER2-positive disease who did not receive trastuzumab (HR 2.13, 95% CI 1.51–3.00, P < 0.0001) had shorter times to CNS metastases compared with patients with HER2-positive disease who had received trastuzumab as first-line therapy for metastases. Furthermore, patients with HER2-negative disease (HR 1.66, 95% CI 1.31–2.12, P < 0.0001) and patients with HER2-positive disease who had never received trastuzumab (HR 1.34, 95% CI 0.78–2.30, P = 0.28) had an increased hazard of death compared with patients with HER2-positive disease who had received trastuzumab before or at the time of CNS metastases diagnosis.ConclusionIn our cohort of patients with breast cancer and CNS metastases, patients with HER2-positive disease treated with trastuzumab had longer times to development of and better survival from CNS metastases compared with patients with HER2-positive disease who had never received trastuzumab and patients with HER2-negative breast cancer.     

Central nervous system metastases in a cohort of metastatic breast cancer patients treated with trastuzumab

Background  Several analyses suggest an increase of brain metastases in HER2 over-expressing breast cancers treated with trastuzumab as compared to historical series of unselected patients. Patients and methods  We analyzed the incidence of central nervous system (CNS) metastases in 78 patients with HER2 over-expressing breast cancer treated with trastuzumab between July 2000 and June 2006 at the Oncology Department of University Federico II in Naples. We also characterized and compared patients with and without CNS involvement. Results  The median follow-up was 35.3 months (95%CI 26.3–44); median overall survival was 56 months (95%CIs 46-nr); 5 patients showed CNS involvement before trastuzumab therapy while 31 developed CNS metastases during trastuzumab treatment. The median overall survival after CNS metastases was 25.4 months (95%CIs 15.2-nr); patients with CNS lesions showed worse overall survival than patients without CNS lesions (39.1 vs. 75 months, p = 0.005). Conclusion  CNS metastases are common events in patients with metastatic HER2 over-expressing breast cancer treated with trastuzumab; the impact on survival is detrimental even if survival after CNS metastases is longer than historical reports. Appropriate investigation of the role of CNS imaging screening and the prophylactic treatment strategies for CNS represents a priority research in this setting. E. Montagna and G. Cancello have contributed equally to this work.     

Identifying breast cancer patients at risk for Central Nervous System (CNS) metastases in trials of the International Breast Cancer Study Group (IBCSG).

BACKGROUND: We sought to determine whether a high-risk group could be defined among patients with operable breast cancer in whom a search of occult central nervous system (CNS) metastases was justified. PATIENTS AND METHODS: We evaluated data from 9524 women with early breast cancer (42% node-negative) who were randomized in International Breast Cancer Study Group clinical trials between 1978 and 1999, and treated without anthracyclines, taxanes, or trastuzumab. We identified patients whose site of first event was CNS and those who had a CNS event at any time. RESULTS: Median follow-up was 13 years. The 10-year incidence (10-yr) of CNS relapse was 5.2% (1.3% as first recurrence). Factors predictive of CNS as first recurrence included: node-positive disease (10-yr = 2.2% for > 3 N+), estrogen receptor-negative (2.3%), tumor size > 2 cm (1.7%), tumor grade 3 (2.0%), < 35 years old (2.2%), HER2-positive (2.7%), and estrogen receptor-negative and node-positive (2.6%). The risk of subsequent CNS recurrence was elevated in patients experiencing lung metastases (10-yr = 16.4%). CONCLUSION: Based on this large cohort we were able to define risk factors for CNS metastases, but could not define a group at sufficient risk to justify routine screening for occult CNS metastases.     

Brain metastases in patients who receive trastuzumab-containing chemotherapy for HER2-overexpressing metastatic breast cancer

Background  Recently, a high rate of brain metastases has been reported among patients with human epidermal growth factor receptor (HER2)-overexpressing metastatic breast cancer who were treated with trastuzumab. The present study examined risk factors for the development of brain metastasis in patients with HER2-overexpressing breast cancer who were treated with trastuzumab. Methods  We retrospectively reviewed 204 patients with HER-2-overexpressing breast cancer who were treated with a trastuzumab-containing regimen between 1999 and 2006. Patients with clinical symptoms were diagnosed as having brain metastases when brain magnetic resonance imaging (MRI) or a computed tomography (CT) scan revealed positive findings for brain metastases. The median follow-up time of this cohort was 53.6 months. Results  Among the patients who received a trastuzumabcontaining regimen, 74 patients (36.3%) developed brain metastases. The median survival from the diagnosis of brain metastases was 13.5 months (95% confidence interval [CI], 12.2–14.7 months). The median time interval between the beginning of trastuzumab treatment and the diagnosis of brain metastases was 13.6 months (range, 0.0–45.8 months). Among patients with brain metastases, the median overall survival period was 39 months. A multivariate logistic regression analysis showed that age (≤50 years), recurrent breast cancer, and liver metastases were significant risk factors for the development of brain metastases. Conclusion  Patients with HER2-overexpressing breast cancer treated with trastuzumab had a high incidence of brain metastases (36.3%). Routine screening for brain metastases 1 year after the start of trastuzumab treatment, may be warranted in younger patients (≤50 years) who had recurrent breast cancer with liver metastases.     

Central nervous system metastases in breast cancer patients administered trastuzumab

Amplification or over-expression of the HER2/neu receptor is present in 20-30% of invasive breast cancers and in 60% of intraductal breast carcinomas. Patients with HER2/neu gene aberrations have more aggressive disease, frequent disease recurrence and a shorter survival. Trastuzumab (herceptin) is a monoclonal antibody selectively directed against the HER2/neu receptor. The addition of trastuzumab to chemotherapy in HER2/neu-positive advanced breast cancer patients has increased complete and partial response rates, and prolonged time to progression and overall survival. However, a relatively common failure site in patients administered trastuzumab is the central nervous system (CNS). CNS metastases in these patients seem to develop despite responses achieved in extracerebral sites. This pattern of failure has mainly been attributed to the lack of trastuzumab penetration to the CNS owing to the high molecular weight (145 kDa) of this molecule. Additionally, increased risk of CNS relapse may be associated with improved systemic control of extracerebral metastases and prolonged survival without brain protection (a sanctuary site). Finally, it was postulated that HER2/neu over-expression and/or amplification might predispose to brain metastases. The aim of this article is to discuss the pathophysiology of this phenomenon and its clinical implications.     

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

BACKGROUND:

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

METHODS:

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

RESULTS:

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

CONCLUSIONS:

To the authors' knowledge, this is the first population‐based cancer registry study analyzing factors associated with CNS recurrence in a general population of newly diagnosed breast cancer patients with known HER2 status. The data from the current study provide evidence that patients with HER2‐positive breast cancer have a significantly higher incidence of CNS metastasis after treatment with trastuzumab. Improvements in systemic control and overall survival associated with trastuzumab‐based therapy may lead to an “unmasking” of CNS disease recurrence that would otherwise remain clinically silent before a patient's death. Cancer 2011. © 2010 American Cancer Society.     

Central nervous system metastases in women who receive trastuzumab-based therapy for metastatic breast carcinoma

BACKGROUND: Women with HER-2 overexpressing metastatic breast carcinoma benefit from trastuzumab-based therapy, but trastuzumab does not cross the blood-brain barrier. The authors characterized central nervous system (CNS) disease in these women. METHODS: Using pharmacy records, the authors retrospectively identified 153 women treated with trastuzumab alone or with chemotherapy for HER-2-positive metastatic breast carcinoma at Dana-Farber Partners Cancer Care from June 1998 to December 2000. A study cohort of 122 patients was identified after excluding patients without adequate clinical follow-up or who had CNS disease before trastuzumab treatment. Central nervous system disease was defined as one or more brain metastases or as leptomeningeal carcinomatosis. The median follow-up of this cohort was 23 months. RESULTS: Central nervous system metastases were identified in 34% of patients (95% confidence interval, 26-44%) at a median of 16 months after diagnosis of metastatic breast carcinoma and 6 months from the beginning of trastuzumab therapy. Ninety-three percent of patients with CNS disease presented with clinical symptoms. Five percent of patients with CNS disease had leptomeningeal involvement alone, although 14% had leptomeningeal involvement and parenchymal brain metastases. Fifty percent of patients were responding or had stable disease while receiving trastuzumab at other disease sites at the time of diagnosis of CNS metastasis. The median survival period after CNS metastases was 13 months. Fifty percent of patients died of progressive CNS disease. Patients receiving trastuzumab as first-line therapy for metastatic disease frequently developed brain metastases while responding to or stable on trastuzumab at other disease sites. CONCLUSIONS: Metastatic breast carcinoma to the CNS is common among patients receiving trastuzumab-based therapy, including patients responding to therapy outside the CNS. This may be due either to predilection for the CNS by HER-2-positive tumor cells and/or poor penetration of the CNS by trastuzumab or to improved visceral disease control leading to a longer life and onset of late tumor spread to the CNS. Efforts to characterize other risk factors for development of CNS disease, optimal screening algorithms, and new treatment strategies may be warranted.     

EGFR,pMAPK, pAkt and PTEN status by immunohistochemistry: correlation with clinical outcome in HER2-positive metastatic breast cancer patients treated with trastuzumab

BackgroundIn an attempt to identify markers of resistance to trastuzumab, we evaluated both the profiling of human epidermal growth factor receptor 2 (HER2)-positive tumor cells measuring the relative levels of EGFR, pMAPK, pAkt and PTEN and their correlations with clinical outcome in HER2-positive metastatic breast cancer patients treated with trastuzumab.Patients and methodsTumor tissues for this retrospective analysis were available from 45 out of 76 patients with metastatic breast cancer treated from April 1999 to March 2006 with trastuzumab-based therapy at our Institution. Evaluations of EGFR, pMAPK, pAkt and PTEN status by immunohistochemistry (IHC) were carried out on all 45 tissue samples and their correlations with response to trastuzumab, incidence of central nervous system (CNS) metastases, time to progression (TTP), overall survival from diagnosis of breast cancer (OS1), from diagnosis of metastatic disease (OS2) and from the start of trastuzumab (OS3) were analyzed.ResultsWe observed that TTP (P = 0.001) and median OS2 and OS3 were significantly longer in patients responsive to trastuzumab-based regimen compared with nonresponsive patients. EGFR, pMAPK, pAkt and PTEN status by IHC were not significantly associated with response to trastuzumab, TTP, overall survival (OS1, OS2, OS3) and CNS metastases incidence. A trend for shorter OS3 was observed for pMAPK-positive patients compared with pMAPK-negative patients (22.8 versus 31.2 months; P = 0.076). Median OS1 resulted shorter in 22 pAkt-positive patients (69.8 months) compared with 23 pAkt-negative patients (108.2 months); P = 0.091. It is likely that high expression of pMAPK (pMAPK-positive status) or pAkt (pAkt-positive status) could identify a subgroup of HER2-positive tumors with high activity of proliferation and survival pathways and with resistance to trastuzumab.ConclusionsIn HER2-positive metastatic breast cancers, EGFR, pMAPK, pAkt and PTEN status evaluated by IHC was not significantly associated with response to trastuzumab, TTP, OS and CNS metastases incidence. However, HER2 status determined by IHC and/or FISH assays may not be sufficient to predict response to trastuzumab-based therapy.     

The risk of central nervous system metastases after trastuzumab therapy in patients with breast carcinoma

BACKGROUND: Trastuzumab, which is a large monoclonal antibody that is efficacious in the treatment of patients with HER-2/neu-overexpressing, metastatic breast carcinoma, does not penetrate the blood-brain barrier and, thus, may allow the brain to become a sanctuary site for micrometastases. Few studies have compared the risk of central nervous system (CNS) metastases in patients treated with or without trastuzumab. METHODS: The authors conducted a retrospective cohort study that compared 264 patients who did not receive trastuzumab therapy with 79 patients who received trastuzumab therapy. The study was powered to detect an effect size of 0.3, which was deemed clinically significant to change future management. RESULTS: CNS metastases developed in 48.1% of patients on trastuzumab-based therapy and in 46.6% of patients on nontrastuzumab-based therapy. The association between trastuzumab therapy and subsequent CNS metastases (either brain or leptomeningeal) was not significant, with a multivariate-adjusted odds ratio of 0.91 (95% confidence interval, 0.64-1.88; P = 0.79). Similarly, there was no evidence of an association between trastuzumab and brain metastases alone (P = 0.67) or leptomeningeal metastases alone (P = 0.14). The median overall survival after the diagnosis of all CNS metastases was 26.3 months for patients who did not receive trastuzumab and 24.9 months for patients who received trastuzumab (P = 0.7). A multivariate logistic regression model found that patient age at diagnosis (P < 0.05), positive lymph node status at presentation (P < 0.01), and liver metastases (P < 0.01) were significant predictors of CNS metastases. Lung metastases showed a borderline significant P value (0.056). CONCLUSIONS: Despite the impression of many oncologists, the results of this study did not support an association between trastuzumab therapy and an increased risk of CNS metastases.     

Concurrent whole-brain radiotherapy with trastuzumab for treatment of brain metastases in breast cancer patients: questions and answers

PurposeWe retrospectively assessed the use of trastuzumab concurrently with whole-brain radiotherapy (WBRT) for brain metastases.Patients and methodsFrom April 2001 to April 2007, 31 patients with brain metastases from HER2-positive breast cancer were referred for WBRT with concurrent trastuzumab. In most cases, concurrent WBRT delivered 30 Gy in 10 daily fractions. In six patients, other fractionations were chosen because of either poor performance status or patients’ convenience.ResultsAt time of brain progression, median age was 55 years (range: 38 to 73 years) and all patients had a performance status of 0 to 2. Median time to brain progression was 10.5 months. Following WBRT, radiological responses were observed in 23 patients (74.2%), including six patients (19.4%) with complete radiological responses and 17 patients (54.8%) with partial radiological response. Clinical responses were observed in 27 patients (87.1%). Median survival from the start of WBRT was 18 months (range: two to 65 months). No grade 2 or more acute toxicity was observed.ConclusionOur results suggest that trastuzumab concurrently with WBRT may have a potential clinical impact with low toxicity. Although promising, these preliminary data warrant further validation of trastuzumab as radio sensitizer for WBRT in brain metastases from breast cancer in the setting of a clinical trial. Larger prospective studies are needed to confirm these results.     

Primary breast cancer phenotypes associated with propensity for central nervous system metastases

BACKGROUND: There is anecdotal evidence that the incidence of central nervous system (CNS) metastases in breast cancer patients is increasing. It is unclear whether specific tumor biological properties or the use of systemic therapies influence this risk. METHODS: Using a database of 10,782 patients, 2685 patients were identified who experienced recurrence distantly. Clinical and biological features were analyzed in 2 ways: (1) patients who ever had versus those who never had CNS metastases, and (2) CNS metastases as the first site of recurrence versus those who had other sites. Correlations of survival after CNS metastasis with clinical and biologic features were also analyzed. RESULTS: In the ever versus never analysis, CNS metastases were significantly associated with younger age, premenopausal status, infiltrating ductal carcinoma histology (IDC), estrogen receptor (ER) and progesterone receptor (PR) negativity, low Bcl-2, high S-phase, aneuploidy, and altered p53. Tumor size, lymph node status, and use of adjuvant systemic therapy played little role. HER-2 overexpression was not associated with an increased risk in these patients (none of whom were treated with trastuzumab) (P = .91). However, epidermal growth factor receptor (EGFR) overexpression was associated with increased risk (P = .02). A multivariate analysis revealed ER negativity (odds ratio [OR] 2.8, P < .001), IDC histology (OR 2.5, P = .02), and young age (P < .001) as independent factors for CNS metastases. The clinical and biologic profiles of primary tumors with CNS metastases at first recurrence did not differ from those with CNS metastases after recurrence to other sites, except for HER-2 status. HER-2-positive tumors were not more likely to undergo recurrence initially in the CNS (P =.04). The median survival after CNS metastases was 5.5 months and HER-2-positive patients had a shorter survival. CONCLUSIONS: Younger patients with hormone receptor-negative, highly proliferative, genomically unstable, and p53-altered tumors were at increased relative risk for CNS metastases. HER-2 expression and adjuvant systemic therapies did not increase this risk.