Fractionated radiosurgery for brain metastases in 43 patients with breast carcinoma

Dose-Response Effect and Dose-Toxicity in Stereotactic Radiotherapy for Brain Metastases: A Review

Simple Summary

Brain metastases are one of the most frequent complications for cancer patients. Stereotactic radiosurgery is considered a cornerstone treatment for patients with limited brain metastases and the ideal dose and fractionation schedule still remain unknown. The aim of this literature review is to discuss the dose-effect relation in brain metastases treated by stereotactic radiosurgery, accounting for fractionation and technical considerations.

Abstract

For more than two decades, stereotactic radiosurgery has been considered a cornerstone treatment for patients with limited brain metastases. Historically, radiosurgery in a single fraction has been the standard of care but recent technical advances have also enabled the delivery of hypofractionated stereotactic radiotherapy for dedicated situations. Only few studies have investigated the efficacy and toxicity profile of different hypofractionated schedules but, to date, the ideal dose and fractionation schedule still remains unknown. Moreover, the linear-quadratic model is being debated regarding high dose per fraction. Recent studies shown the radiation schedule is a critical factor in the immunomodulatory responses. The aim of this literature review was to discuss the dose–effect relation in brain metastases treated by stereotactic radiosurgery accounting for fractionation and technical considerations. Efficacy and toxicity data were analyzed in the light of recent published data. Only retrospective and heterogeneous data were available. We attempted to present the relevant data with caution. A BED10 of 40 to 50 Gy seems associated with a 12-month local control rate >70%. A BED10 of 50 to 60 Gy seems to achieve a 12-month local control rate at least of 80% at 12 months. In the brain metastases radiosurgery series, for single-fraction schedule, a V12 Gy < 5 to 10 cc was associated to 7.1–22.5% radionecrosis rate. For three-fractions schedule, V18 Gy < 26–30 cc, V21 Gy < 21 cc and V23 Gy < 5–7 cc were associated with about 0–14% radionecrosis rate. For five-fractions schedule, V30 Gy < 10–30 cc, V 28.8 Gy < 3–7 cc and V25 Gy < 16 cc were associated with about 2–14% symptomatic radionecrosis rate. There are still no prospective trials comparing radiosurgery to fractionated stereotactic irradiation.

Treatment Patterns and Outcomes of Women with Symptomatic and Asymptomatic Breast Cancer Brain Metastases: A Single-Center Retrospective Study

BACKGROUND

Breast cancer is the most common cancer among women worldwide and the second leading cause of brain metastases (BrM). We assessed the treatment patterns and outcomes of women treated for breast cancer BrM at our institution in the modern era of stereotactic radiosurgery (SRS).

MATERIALS AND METHODS

We conducted a retrospective analysis of women (≥18 years of age) with metastatic breast cancer who were treated with surgery, whole brain radiotherapy (WBRT), or SRS to the brain at the Sunnybrook Odette Cancer Centre, Toronto, Canada, between 2008 and 2018. Patients with a history of other malignancies and those with an uncertain date of diagnosis of BrM were excluded. Descriptive statistics were generated and survival analyses were performed with subgroup analyses by breast cancer subtype.

RESULTS

Among 683 eligible patients, 153 (22.4%) had triple-negative breast cancer, 188 (27.5%) had HER2+, 246 (36.0%) had hormone receptor (HR)+/HER2-, and 61 (13.3%) had breast cancer of an unknown subtype. The majority of patients received first-line WBRT (n = 459, 67.2%) or SRS (n = 126, 18.4%). The median brain-specific progression-free survival and median overall survival (OS) were 4.1 months (interquartile range [IQR] 1.0-9.6 months) and 5.1 months (IQR 2.0-11.7 months) in the overall patent population, respectively. Age >60 years, presence of neurological symptoms at BrM diagnosis, first-line WBRT, and HER2- subtype were independently prognostic for shorter OS.

CONCLUSION

Despite the use of SRS, outcomes among patients with breast cancer BrM remain poor. Strategies for early detection of BrM and central nervous system-active systemic therapies warrant further investigation.

IMPLICATIONS FOR PRACTICE

Although triple-negative breast cancer and HER2+ breast cancer have a predilection for metastasis to the central nervous system (CNS), patients with hormone receptor-positive/HER2- breast cancer represent a high proportion of patients with breast cancer brain metastases (BrM). Hence, clinical trials should include patients with BrM and evaluate CNS-specific activity of novel systemic therapies when feasible, irrespective of breast cancer subtype. In addition, given that symptomatic BrM are associated with shorter survival, this study suggests that screening programs for the early detection and treatment of breast cancer BrM warrant further investigation in an era of minimally toxic stereotactic radiosurgery.

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.

Efficacy of gamma knife radiosurgery in brain metastases of primary gynecological tumors

OBJECTIVE

Gynecological brain metastases (BM) are rare and usually develop as part of widespread disseminated disease. Despite treatment, the majority of these patients do not survive > 1 year due to advanced extracranial disease. The use of Gamma Knife Radiosurgery (GKRS) for gynecological BM is not well known. The goal of this study is to evaluate the efficacy of GKRS for gynecological BM.

METHODS

We performed a retrospective study of patients with gynecological BM who underwent GKRS between 2002 and 2015. A total of 41 patients were included. Outcome measures were local tumor control (LC), development of new BM and/or leptomeningeal disease, overall intracranial progression free survival (PFS) and survival.

RESULTS

LC was 100%, 92%, 80%, 75% and 67% at 3, 6, 9, 12 and 15 months, respectively. PFS was 90%, 61%, 41%, 23% and 13% at 3, 6, 9, 12 and 15 months, respectively. During follow-up (FU), 18 (44%) patients had intracranial progression. Distant BM occurred in 29% of the patients. Local recurrence and distant recurrence occurred after a mean FU time of 15.5 (2.6-71.9) and 11.4 (2-40) months, respectively. Thirty-one (76%) patients died due to extracranial tumor progression and only 2 (5%) patients died due to progressive intracranial disease. The overall mean survival from time of GKRS was 19 months (1-109). The 6-month, 1-year, and 2-year survival rate from the time of GKRS were 71%, 46%, and 22%, respectively.

CONCLUSION

GKRS is a good treatment option for controlling gynecological BM. As most patients die due to extracranial tumor progression, their survival might improve with better systemic treatment options in addition to GKRS.

Single institution validation of a modified graded prognostic assessment of patients with breast cancer brain metastases

Aim:

The number of breast cancer brain metastases is a prognostic clinical variable in the modified graded prognostic assessment (GPA) Index for breast cancer.

Patients & methods:

We retrospectively gathered data from 127 breast cancer patients who underwent radiation therapy for brain metastasis. Patients were stratified by both breast GPA and modified breast GPA scores, and survival was determined using the Kaplan–Meier curves and Cox proportional hazards model.

Results & Conclusion:

The Kaplan–Meier curve for patients under the breast GPA classification were not significant, but were significant under the modified breast GPA classification. The inclusion of number of brain metastases into the modified breast GPA index improved prognosis, thus validating the use of the modified breast GPA in prognosticating patient outcome.

Brain Metastases Secondary to Breast Cancer: Symptoms, Prognosis and Evolution

Aims and Background

Brain metastases confer a worse prognosis to breast cancer because they determine a severe increase in mortality. The aim of this study was to identify the early symptoms in patients with brain metastases after breast cancer treatment and to evaluate the median survival rate in women with single and operable brain lesions.

Patients and Methods

We examined 43 patients with brain metastases secondary to breast cancer treated in the Oncological Institute Prof I Chiricuţă, Cluj-Napoca, during the period 2000-2006.

Results

The median interval between the breast cancer diagnosis and detection of central nervous metastases was 21 months. The most frequent symptoms were headache, gait disturbance, nausea and vomiting. Patients with a single brain lesion had a median survival of 23 months compared to only 7 months in case of patients with multiple brain metastases.

Conclusions

The prognosis is worse in patients with solitary brain metastases secondary to breast cancer than in patients who present extracranial metastases. Among factors considered favorable in these patients are a single brain lesion, accessibility to surgery, and the absence of associated extracranial metastases.

Brain Metastases in Breast Cancer: Analysis of the Role of HER2 Status and Treatment in the Outcome of 94 Patients

Aims and background

We investigated the impact of human epidermal growth factor receptor 2 (HER2) and prognostic factors in the outcome of patients with breast cancer that developed brain metastases.

Methods

The data from 94 patients who received multidisciplinary therapy from 2001 to 2007 were retrospectively reviewed. Patients were assigned according to their HER2 status, and overall survival and time to brain metastases recurrence/progression were evaluated. The prognostic value of age, presence of extracerebral metastases, recursive partitioning analysis class, hormone therapy, systemic therapy and trastuzumab was assessed.

Results

The median overall survival and time to brain disease progression were 7.1 and 6.5 months, respectively. HER2 positivity (P = 0.006), treatment with trastuzumab (P = 0.025), chemotherapy (P = 0.011) and recursive partitioning analysis class I-II (P <0.001) were associated with prolonged survival on univariate analysis. On multivariate analysis, only recursive partitioning analysis class I-II (P <0.001) and triple-negative disease (P = 0.04) remained significant for overall survival, whereas time to brain metastases progression was only associated with recursive partitioning analysis class I-II (P = 0.001). The time from the diagnosis of primary disease to brain metastasis was slightly shorter in the HER2+ patients than in HER2– patients (36 vs 39 months). Intensified local treatment of brain metastasis incorporating whole-brain radiotherapy and/or radiosurgery and neurosurgery did not affect survival. Patients with triple-negative disease presented a significantly lower survival than the rest of the cohort (4 vs 8 months; P = 0.012).

Conclusions

Recursive partitioning analysis class I-II was found to be the strongest independent predictive factor. Treatment with trastuzumab in HER2+ patients appeared to improve overall survival, probably due to the better control of systemic metastatic disease, but did not maintain significance in multivariate analysis. The dismal prognosis of patients with triple-negative breast cancer highlights the need to develop novel therapies to improve the poor survival.

Validation and Development of a Modified Breast Graded Prognostic Assessment As a Tool for Survival in Patients With Breast Cancer and Brain Metastases

PURPOSE

Several indices have been developed to predict overall survival (OS) in patients with breast cancer with brain metastases, including the breast graded prognostic assessment (breast-GPA), comprising age, tumor subtype, and Karnofsky performance score. However, number of brain metastases-a highly relevant clinical variable-is less often incorporated into the final model. We sought to validate the existing breast-GPA in an independent larger cohort and refine it integrating number of brain metastases.

PATIENTS AND METHODS

Data were retrospectively gathered from a prospectively maintained institutional database. Patients with newly diagnosed brain metastases from 1996 to 2013 were identified. After validating the breast-GPA, multivariable Cox regression and recursive partitioning analysis led to the development of the modified breast-GPA. The performances of the breast-GPA and modified breast-GPA were compared using the concordance index.

RESULTS

In our cohort of 1,552 patients, the breast-GPA was validated as a prognostic tool for OS (P < .001). In multivariable analysis of the breast-GPA and number of brain metastases (> three v ≤ three), both were independent predictors of OS. We therefore developed the modified breast-GPA integrating a fourth clinical parameter. Recursive partitioning analysis reinforced the prognostic significance of these four factors. Concordance indices were 0.78 (95% CI, 0.77 to 0.80) and 0.84 (95% CI, 0.83 to 0.85) for the breast-GPA and modified breast-GPA, respectively (P < .001).

CONCLUSION

The modified breast-GPA incorporates four simple clinical parameters of high prognostic significance. This index has an immediate role in the clinic as a formative part of the clinician's discussion of prognosis and direction of care and as a potential patient selection tool for clinical trials.

Brain metastases in breast cancer

Brain metastases are less common than bone or visceral metastases in patients with breast cancer. The overall prognosis of breast cancer patients with brain metastases remains poor, and these metastases are less responsive to systemic therapies. Brain metastasis is associated with a reduced quality of life due to progressive neurologic impairments. Recently, a trend of increased incidence of brain metastases in breast cancer has been noted. Reasons for this increased incidence include the more frequent use of sensitive detection methods such as contrast-enhanced magnetic resonance imaging and increased awareness of brain metastasis among patients and clinicians. Adjuvant and systemic therapy with drugs that have a low blood-brain barrier penetrance can lead to an increased risk of brain metastases in breast cancer patients. Molecular subtype is a predictive factor for overall survival after developing brain metastases. Patients who do not have a poor prognosis based on previously identified prognostic factors should be treated with radiation therapy to control symptoms. Whole-brain radiation therapy, stereotactic irradiation and surgery are tools for the local treatment of brain metastases. Novel molecular target therapy, including HER2-targeted therapy, has demonstrated an antitumor effect on brain metastases. In this review, we provide a practical algorithm for the treatment of breast cancer brain metastases. This review provides an overview of the incidence, risk factors, diagnosis, prognostic factors and current and potential future management strategies of breast cancer brain metastases.

[New external radiotherapy technologies for breast cancer]

The purpose of new radiotherapy techniques is to better deliver dose conformation in the tumour volume while diminishing organs at risk exposition. Their development is soaring in the breast cancer field in the adjuvant setting with intensity-modulated radiation therapy but also in cerebral and extracerebral oligometastastic presentation. Their usage is still being debated for breast cancer care. The objective of this narrative review is to list and discuss clinical data at our disposal for these news technologies.

Identification of breast cancer patients with a high risk of developing brain metastases: a single-institutional retrospective analysis

Background

The objective of this study was to identify breast cancer patients with a high risk of developing brain metastases who may benefit from pre-emptive medical intervention.

Methods

Medical records of 352 breast cancer patients with local or locoregional disease at diagnosis were retrospectively analysed. The brain metastasis-free survival was estimated using the Kaplan-Meier method and patient groups were compared using the log rank test. The simultaneous relationship of multiple prognostic factors was assessed using Cox’s proportional hazard regression analysis. The Fisher exact test was used to test the difference of proportions for statistical significance.

Results

On univariate analysis, statistically highly significant unfavourable risk factors for the brain metastasis-free survival were negative ER status, negative PR status, and triple negative tumor subtype. Young age at diagnosis (≤35 years) and advanced disease stage were not statistically significant (p = 0.10). On multivariate analysis, the only independent significant factor was the ER status (negative ER status; hazard radio (95% confidence interval), 5.1 (1.8-14.6); p = 0.003). In the subgroup of 168 patients with a minimum follow-up of 24 months, 49 patients developed extracranial metastases as first metastatic event. Of those, 7 of 15 (46.6%) with a negative ER status developed brain metastases compared to 5 of 34 (14.7%) with a positive ER status (Fisher exact test, p = 0.03). The median time interval (minimum-maximum) between the diagnosis of extracranial and brain metastases was 7.5 months (1-30 months).

Conclusions

Breast cancer patients with extracranial metastasis and negative ER status exhibited an almost 50% risk of developing brain metastasis during their course of disease. Future studies are highly desired to evaluate the efficacy of pre-emptive medical intervention such as prophylactic treatment or diagnostic screening for high risk breast cancer patients.

A volumetric study of CyberKnife hypofractionated stereotactic radiotherapy as salvage for progressive malignant brain tumors: initial experience

OBJECTIVE

Radiosurgery is frequently offered to patients with progressive malignant brain tumors if radiation therapy or chemotherapy fails to provide local control. The use of single-shot regimens, however, is limited by the risk of complications when the tumor is large, surrounded by edema or has been pre-treated with radiation. Hypofractionation may confer safety but has not been tested for these difficult tumors. We report the results of hypofractionation as an alternative option in a small cohort of progressive malignant brain tumors.

METHODS

Hypofractionated CyberKnife radiotherapy was chosen for 18 progressive malignant brain tumors (six high-grade gliomas and 12 metastatic lesions) in 15 patients because of size, previous treatment with radiation or surrounding edema. The mean dose was 21 +/- 4 Gy and the number of fractions was 5 +/- 0.6. The volume of each tumor at treatment was compared with the volume at follow-up.

RESULTS

Thirteen of the 18 tumors (72%) showed a volume decrease. The average volume change was a decrease of 16 +/- 58% (median: 20%) with a follow-up of 180 +/- 121 days (median: 172 days). Toxicity occurred in only one patient, with symptoms improving on steroids.

DISCUSSION

Progression of malignant brain tumors not ideal for single-shot radiosurgery can be arrested or reversed, at least for short periods, with minimal toxicity using hypofractionated radiotherapy. Longer studies will be needed to assess durability of this response in these difficult tumors.

Stereotactic radiosurgery in the treatment of brain metastases: the current evidence

Chemotherapy has made substantial progress in the therapy of systemic cancer, but the pharmacological efficacy is insufficient in the treatment of brain metastases. Fractionated whole brain radiotherapy (WBRT) has been a standard treatment of brain metastases, but provides limited local tumor control and often unsatisfactory clinical results. Stereotactic radiosurgery using Gamma Knife, Linac or Cyberknife has overcome several of these limitations, which has influenced recent treatment recommendations. This present review summarizes the current literature of single session radiosurgery concerning survival and quality of life, specific responses, tumor volumes and numbers, about potential treatment combinations and radioresistant metastases. Gamma Knife and Linac based radiosurgery provide consistent results with a reproducible local tumor control in both single and multiple brain metastases. Ideally minimum doses of ≥18Gy are applied. Reported local control rates were 90-94% for breast cancer metastases and 81-98% for brain metastases of lung cancer. Local tumor control rates after radiosurgery of otherwise radioresistant brain metastases were 73-90% for melanoma and 83-96% for renal cell cancer. Currently, there is a tendency to treat a larger number of brain metastases in a single radiosurgical session, since numerous studies document high local tumor control after radiosurgical treatment of >3 brain metastases. New remote brain metastases are reported in 33-42% after WBRT and in 39-52% after radiosurgery, but while WBRT is generally applied only once, radiosurgery can be used repeatedly for remote recurrences or new metastases after WBRT. Larger metastases (>8-10cc) should be removed surgically, but for smaller metastases Gamma Knife radiosurgery appears to be equally effective as surgical tumor resection (level I evidence). Radiosurgery avoids the impairments in cognition and quality of life that can be a consequence of WBRT (level I evidence). High local efficacy, preservation of cerebral functions, short hospitalization and the option to continue a systemic chemotherapy are factors in favor of a minimally invasive approach with stereotactic radiosurgery.

Survival following gamma knife radiosurgery for brain metastasis from breast cancer

Background

Breast cancer is the second most common cause of brain metastases in the United States. Although breast cancer induced brain metastases represent an incurable condition, some patients experience prolonged survival. In this retrospective study, we examine a cohort of patients with brain metastases from breast cancer treated with Gamma Knife stereotactic radiosurgery to identify factors that predict better outcomes.

Methods

A retrospective database of 100 patients treated for brain metastases due to breast cancer via Gamma Knife radiosurgery (GKS) from July 1998 through March 2009 was reviewed. Patients who received radiosurgery as sole treatment, as a planned boost after whole brain radiotherapy or surgical resection, or as salvage after prior whole brain radiation therapy (WBRT) or surgical resection were included. Prognostic factors identified to be significant for survival in previous brain metastasis studies were analyzed for significance by univariate and multivariate Cox analysis.

Results

Overall, the median brain progression-free survival time was 7.1 months and the median survival time was 12.3 months. No prognostic variables were significant for brain progression-free survival. For patients treated with a planned GKS after WBRT, GKS as sole treatment, GKS salvage after WBRT, GKS boost after surgery, or GKS for surgical salvage the median survival times (MSTs) were as follows: 12.2 months, 12.4 months, 9.5 months, 27.6 months and 33.4 months respectively. Differences between the groups were not significant (p = 0.06); however, GKS boost after surgery and GKS for salvage after surgery did have a trend toward better overall survival.

The MST for patients of age <65 years was 14.5 months, compared to age ≥65 which was 7.7 months (p = 0.06) and remained a significant prognostic factor for overall survival on multivariate analysis. The MST for patients with a single lesion was 16.9 months, not significantly different than the MST of 14.5 months for patients with 2–3 lesions. However patients with >3 lesions had a MST of 5.9 months, which was significantly worse. Breast cancer subtype as approximated by biomarkers and KPS were not significant predictors of overall survival and stage at initial diagnosis was inversely associated with survival.

Conclusion

Stereotactic radiosurgery offers good local control and prolonged survival in selected patients. Age and number of lesions are strong predictors of overall survival.

Gamma knife surgery for brain metastases from ovarian cancer

Background

Brain metastases from ovarian cancer are rare, but their incidence is increasing. The purpose of this study was to investigate the characteristics of brain metastases from ovarian cancer, and to assess the efficacy of treatment with gamma knife surgery (GKS).

Methods

A retrospective review was performed of patients with brain metastases from ovarian cancer who were treated at the Tokyo Gamma Unit Center from 2006 to 2010.

Results

Sixteen patients were identified. Their median age at diagnosis of brain metastases was 56.5 years, the median interval from diagnosis of ovarian cancer to brain metastases was 27.5 months, and the median number of brain metastases was 2. The median Karnofsky Performance Score (KPS) at the first GKS was 80. The median survival following diagnosis of brain metastases was 12.5 months, and 6-month and 1-year survival rates were 75 % and 50 %, respectively. The tumor control rate was 86.4 %. The KPS (<80 vs ≥80) and total volume of brain metastases (<10 cm³ vs ≥10 cm³) were significantly associated with survival according to a univariate analysis (p = 0.004 and p = 0.02, respectively).

Conclusions

The results of this study suggest that GKS is an effective remedy and acceptable choice for the control of brain metastases from ovarian cancer.

Improvement of survival and prospect of cure in patients with metastatic breast cancer

Patients with metastatic breast cancer have traditionally been considered incurable with conventional treatment. However, 5-10% of those patients survive more than 5 years, and 2-5% survive more than 10 years. Recent studies suggest that the survival of patients with metastatic breast cancer has been slowly improving. In this review, we examine the possible curative approach for a certain group of patients with metastatic breast cancer. We identify that patients most likely to benefit from such an aggressive approach are young and have good performance status, adequate body functional reserve, long disease-free interval before recurrence, oligometastatic disease, and low systemic tumor load. An aggressive multidisciplinary approach including both local treatment of macroscopic disease and systemic treatment of microscopic disease can result in prolonged disease control in certain patients with metastatic breast cancer. Whether patients with prolonged disease control are "cured" remains controversial.

Effect of tumor subtype on survival and the graded prognostic assessment for patients with breast cancer and brain metastases

PURPOSE

The diagnosis-specific Graded Prognostic Assessment (GPA) was published to clarify prognosis for patients with brain metastases. This study refines the existing Breast-GPA by analyzing a larger cohort and tumor subtype.

METHODS AND MATERIALS

A multi-institutional retrospective database of 400 breast cancer patients treated for newly diagnosed brain metastases was generated. Prognostic factors significant for survival were analyzed by multivariate Cox regression and recursive partitioning analysis (RPA). Factors were weighted by the magnitude of their regression coefficients to define the GPA index.

RESULTS

Significant prognostic factors by multivariate Cox regression and RPA were Karnofsky performance status (KPS), HER2, ER/PR status, and the interaction between ER/PR and HER2. RPA showed age was significant for patients with KPS 60 to 80. The median survival time (MST) overall was 13.8 months, and for GPA scores of 0 to 1.0, 1.5 to 2.0, 2.5 to 3.0, and 3.5 to 4.0 were 3.4 (n = 23), 7.7 (n = 104), 15.1 (n = 140), and 25.3 (n = 133) months, respectively (p < 0.0001). Among HER2-negative patients, being ER/PR positive improved MST from 6.4 to 9.7 months, whereas in HER2-positive patients, being ER/PR positive improved MST from 17.9 to 20.7 months. The log-rank statistic (predictive power) was 110 for the Breast-GPA vs. 55 for tumor subtype.

CONCLUSIONS

The Breast-GPA documents wide variation in prognosis and shows clear separation between subgroups of patients with breast cancer and brain metastases. This tool will aid clinical decision making and stratification in clinical trials. These data confirm the effect of tumor subtype on survival and show the Breast-GPA offers significantly more predictive power than the tumor subtype alone.

Stereotactic radiosurgery as primary and salvage treatment for brain metastases from breast cancer

Object

To evaluate the role of stereotactic radiosurgery (SRS) in the management of brain metastases from breast cancer, the authors assessed clinical outcomes and prognostic factors for survival.

Methods

The records from 350 consecutive female patients who underwent SRS for 1535 brain metastases from breast cancer were reviewed. The median patient age was 54 years (range 19–84 years), and the median number of tumors per patient was 2 (range 1–18 lesions). One hundred seventeen patients (33%) had a single metastasis to the brain, and 233 patients (67%) had multiple brain metastases. The median tumor volume was 0.7 cm3 (range 0.01–48.9 cm3), and the median total tumor volume for each patient was 4.9 cm3 (range 0.09–74.1 cm3).

Results

Overall survival after SRS was 69%, 49%, and 26% at 6, 12, and 24 months, respectively, with a median survival of 11.2 months. Factors associated with a longer survival included controlled extracranial disease, a lower recursive partitioning analysis (RPA) class, a higher Karnofsky Performance Scale score, a smaller number of brain metastases, a smaller total tumor volume per patient, the presence of deep cerebral or brainstem metastases, and HER2/neu overexpression. Sustained local tumor control was achieved in 90% of the patients. Factors associated with longer progression-free survival included a better RPA class, fewer brain metastases, a smaller total tumor volume per patient, and a higher tumor margin dose. Symptomatic adverse radiation effects occurred in 6% of patients. Overall, the condition of 82% of patients improved or remained neurologically stable.

Conclusions

Stereotactic radiosurgery was safe and effective in patients with brain metastases from breast cancer and should be considered for initial treatment.

Hypofractionated stereotactic radiotherapy for oligometastases in the brain: a single-institution experience

The treatment of brain metastases is changing. Many different radiotherapy options are now available and under clinical evaluation. As part of this effort, we retrospectively evaluated the efficacy and toxicity of hypofractionated stereotactic radiotherapy (HSRT) in patients with up to three brain metastases. Sixty-five patients with 81 lesions were treated with hypofractionated radiotherapy. Median dose was 24 Gy in three fractions. Median follow-up was 24.6 months. Actuarial tumour control was 75 and 45% at 9 months and 24 months after treatment, respectively. Median survival time was 7.5 months, and 32% of the patients died from brain tumour progression. Actuarial overall survival was 75% at 3 months and 25% at 12 months. Recursive partitioning analysis class was the only significant prognostic factor. Neoadjuvant whole-brain radiotherapy (in 29 patients) had no impact on survival or local control. Neurological status improved in 42 patients (65%). Adverse events were rare and usually mild. This experience suggests HSRT should be considered as an alternative approach in the treatment of one to three metastatic lesions in selected patients.

Gamma Knife surgery for brain metastases from gastrointestinal cancer

OBJECT

Brain metastases from gastrointestinal cancers are rare. However, the incidence is increasing because patients with gastrointestinal carcinoma tend to live longer due to earlier diagnosis and more effective treatment of systemic disease. The purpose of this study was to evaluate the efficacy of Gamma Knife surgery (GKS) for the treatment of brain metastases from gastrointestinal cancers.

METHODS

The authors performed a retrospective review of 40 patients (18 women and 22 men) who had undergone GKS to treat a total of 118 metastases from gastrointestinal cancers between January 1996 and December 2006. The mean patient age was 58.7 years, and the mean Karnofsky Performance Scale (KPS) score was 70. There were 7 patients with esophageal cancer, 25 with colon cancer, 5 with rectal cancer, 2 with pancreatic cancer, and 1 with gastric cancer. Nineteen patients were treated with whole-brain radiotherapy and/or local brain radiotherapy before GKS. Twenty-four patients had extracranial metastases, and 3 had an additional primary cancer. The mean metastatic brain tumor volume was 4.3 cm3, and the mean maximum tumor dose varied from 17.1 to 76.7 Gy (mean 41.8 Gy).

RESULTS

Follow-up imaging studies were available in 25 patients with a total of 90 treated metastases. The results demonstrate a tumor control rate of 91%. The median survival time was 6.7 months, and the 6-month and 1-year survival rates were 55 and 25%, respectively. A univariate analysis revealed that the KPS score (<or=70 vs >or=80) was significant (p=0.018) for improved survival.

CONCLUSIONS

Results in this series suggest that GKS can be an effective tool for the treatment of brain metastases from gastrointestinal cancer.

Factors influencing the time to development of brain metastases in breast cancer

This retrospective study analyzed risk factors influencing the time to development of brain metastases with the aim to facilitate the definition of a high-risk population among breast cancer patients. One hundred seventy-four breast cancer patients with brain metastases, treated with whole brain radiotherapy, were evaluated. Statistical analysis included hormone receptor status, HER2/neu status, tumour grading, tumour stage, young age at the time of diagnosis, adjuvant systemic treatment, palliative systemic treatment, metastatic sites (if brain metastases were not the first site of recurrence), and immunotherapy with trastuzumab. Time to development of brain metastases was significantly prolonged by systemic palliative treatment (p< or =0.0001) whereas high tumour grading (p< or =0.04) and trastuzumab therapy (p< or =0.04) significantly shortened this time span. Patients with the brain as first metastatic site, age>35 (p< or =0.001) and stage III (p< or =0.018) at the time of diagnosis had a significantly shorter time to development for brain lesions. These factors should be further validated by a prospective trial to identify a high-risk population amongst breast cancer patients and enable the development of screening programs for early detection.

Brain Metastases From Breast Carcinoma: Validation of the Radiation Therapy Oncology Group Recursive Partitioning Analysis Classification and Proposition of a New Prognostic Score

PURPOSE

To validate the Radiation Therapy Oncology Group Recursive Partitioning Analysis (RTOG RPA) classification and determine independent prognostic factors, to create a simple and specific prognostic score for patients with brain metastases (BM) from breast carcinoma treated with whole-brain radiotherapy (WBRT).

METHODS AND MATERIALS

From January 1998 through December 2003, 132 patients with BM from breast carcinoma were treated with WBRT. We analyzed several potential predictors of survival after WBRT: age, Karnofsky performance status, RTOG-RPA class, number of BM, presence and site of other systemic metastases, interval between primary tumor and BM, tumor hormone receptor (HR) status, lymphocyte count, and HER-2 overexpression.

RESULTS

A total of 117 patients received exclusive WBRT and were analyzed. Median survival with BM was 5 months. One-year and 2-year survival rates were 27.6% (95% confidence interval [CI] 19.9-36.8%) and 12% (95% CI 6.5-21.2%), respectively. In multivariate analysis, RTOG RPA Class III, lymphopenia (< or =0.7 x 10(9)/L) and HR negative status were independent prognostic factors for poor survival. We constructed a three-factor prognostic scoring system that predicts 6-month and 1-year rates of overall survival in the range of 76.1-29.5% (p = 0.00033) and 60.9-15.9% (p = 0.0011), respectively, with median survival of 15 months, 5 months, or 3 months for patients with none, one, or more than one adverse prognostic factor(s), respectively.

CONCLUSIONS

This study confirms the prognostic value of the RTOG RPA classification, lymphopenia, and tumor HR status, which can be used to form a prognostic score for patients with BM from breast carcinoma.

Trastuzumab prolongs overall survival in patients with brain metastases from Her2 positive breast cancer

BACKGROUND

Brain metastases are frequently encountered in Her2 positive advanced breast cancer. It is still not clear, if trastuzumab treatment should be continued following their diagnosis. In this analysis we evaluated if trastuzumab was able to influence time to in-brain progression (TTP) and overall survival (OS). For this reason, we compared patients who continued on trastuzumab with a historical control group.

PATIENTS AND METHODS

Seventeen Her2 positive patients receiving whole brain radiotherapy for brain metastases and continuing on trastuzumab were identified. As historical control group, thirty-six patients treated before 2002 were identified from a breast cancer database. We performed a multivariate analysis (Cox regression) to explore which factors were potentially able to significantly influence TTP and OS.

RESULTS

Median TTP was 6 months, range 1-33+ months. Median OS was 7 months, range 1-38 months. Seventeen patients received trastuzumab after WBRT. Factors associated with prolonged TTP were KPS (p = 0.001), and intensified local treatment (p = 0.004). A trend towards longer TTP was observed in patients treated with trastuzumab (p = 0.068). OS was significantly influenced by KPS (p < 0.001), and continued antibody therapy (p = 0.001).

CONCLUSION

Two parameters were significantly associated with prolonged OS: KPS and trastuzumab. While there was a trend towards prolonged TTP in patients with trastuzumab treatment after WBRT, this did not reach statistical significance. It appears therefore reasonable to suggest continuation of antibody therapy in patients with good performance status despite disease spreading to the brain. Concerning activity of trastuzumab in brain metastases themselves, no final conclusion is possible.

Stereotactic Radiosurgical Treatment of Cerebral Metastases Arising From Breast Cancer

OBJECTIVE

This study was undertaken to evaluate the outcome of patients undergoing stereotactic radiosurgery (SRS) as primary or salvage treatment of brain metastases arising from breast cancer.

MATERIALS AND METHODS

Between July 2000 and September 2005, the medical records of 49 breast cancer patients who underwent SRS for 84 brain metastases were reviewed retrospectively. Thirty-four patients received SRS as primary brain metastasis treatment and 15 patients received SRS as salvage treatment of brain metastasis recurrence following prior whole-brain radiation therapy. The Kaplan-Meier method, univariate comparisons with log-rank test, and multivariate analysis were performed.

RESULTS

Median follow-up was 12 months (range, 5-50 months) and median survival was 19 months for all patients. The 1- and 2-year overall survival (OS) rates were 60%, 56%, and 55%, 23% for initial SRS alone and SRS salvage groups, respectively (P = 0.99). A multivariate analysis showed that a high KPS score (KPS > or =90 vs. <90; P = 0.02), a higher SIR value (SIR > or =6 vs. <6; P = 0.001), postmenopausal status (P = 0.003), and positive estrogen receptor status (P = 0.04) were predictive of better survival. The 1- and 2-year local control rates were 79%, 49%, and 77%, 46% for SRS alone and SRS salvage group, respectively.

CONCLUSION

SRS can be used as primary treatment of brain metastases or salvage of recurrences after whole-brain radiation therapy to achieve good local control on the order of close to 80% at 1 year. The median survival of brain metastasis patients with breast cancer of 19 months appears favorable compared with the general brain metastasis population.

Intensified local treatment and systemic therapy significantly increase survival in patients with brain metastases from advanced breast cancer - a retrospective analysis

BACKGROUND

Brain metastases have evolved from a rare to a frequently encountered event in advanced breast cancer due to advances in palliative systemic treatment.

PATIENTS AND METHODS

All Patients treated at our centre from 1994 to 2004 with WBRT for brain metastases from breast cancer were included. We performed a multivariate analysis (Cox regression) to explore which factors are able to influence significantly cerebral time to progression (TTP) and overall survival (metastatic sites [visceral versus non-visceral], Karnofsky performance score [KPS], age, intensified local treatment [boost irradiation, neuro-surgical resection] further systemic treatment).

RESULTS

Overall 174 patients, median age 51 years, range 27-76 years, were included. Median TTP was 3 months (m), range 1-33+ m. Median overall survival was 7 m, range 1-44 m. Factors significantly influencing TTP were KPS (p = 0.002), intensified local treatment (p < 0.001), and palliative systemic treatment (p = 0.001). Factors significantly influencing survival were intensified local treatment (p = 0.004), metastatic sites (p = 0.008), KPS (p = 0.006), and palliative systemic treatment (p < 0.001).

CONCLUSION

As shown by the significant influence of metastatic sites, some patients die from their advanced systemic tumour situation before they would die from cerebral progression. In other individuals however, intensified local treatment and systemic treatment appear to influence cerebral time to progression and overall survival.

Radiosurgery in Metastatic Brain Cancer

Radiosurgery offers patients with brain metastases an effective and minimally invasive treatment modality. Radiosurgery provides local tumor control and prolongs survival in select patients with brain metastases. This review will discuss numerous aspects of radiosurgery, including the various delivery techniques and radiobiology. Treatment recommendations will be outlined in view of the available clinical data. Although surgery or radiosurgery with whole-brain radiotherapy remains an important option for patients with a solitary brain metastasis, radiosurgery with or without whole-brain radiotherapy should be considered in patients with a limited number of small tumors and a good prognosis.

Gamma knife surgery for the treatment of intracranial metastases from breast cancer

Object. The goal of this study was to evaluate the effectiveness and limitations of gamma knife surgery (GKS) in the treatment of intracranial breast carcinoma lesions.

Methods. A retrospective analysis of the GKS database at the University of Virginia Health System identified 43 patients with a total of 84 lesions who were treated between 1989 and 2000. All patients who received treatment were included in this study. Imaging studies were available in 35 patients with 67 treated lesions.

The overall duration of median survival was 13 months (95% confidence interval [CI] 7–16 months) after radiosurgery. A univariable Cox regression analysis revealed that a single lesion (p = 0.035), a high Karnofsky Performance Scale (KPS) score (p = 0.019), and a high Score Index for Radiosurgery (SIR) in Brain Metastases (p = 0.036) were associated with a significantly lengthened time to local treatment failure. The median duration of survival for patients grouped according to the SIR as low, middle, and high was 3, 8, and 21 months, respectively (p = 0.00033). A multivariable analysis showed that a high KPS score (p = 0.006), a high SIR (p = 0.014), and advanced age (0.038) were predictive of survival. The 1-, 2-, 3-, and 5-year survival rates were 49, 23, 12, and 2%, respectively.

The overall median time to local treatment failure was 10 months (95% CI 6–14 months) after GKS. A univariable analysis demonstrated that a single lesion, higher KPS score, and a higher SIR were associated with a significantly longer time until local treatment failure. A multivariable analysis showed that a higher KPS score and SIR and patients who had received chemotherapy were associated with a significantly longer time to local treatment failure.

Neuroimaging scores given for the enhancement pattern (ring-enhancing, heterogeneous, and homogeneous signal), amount of necrosis (none, < 50%, and > 50%), and mass effect (none, mild, moderate, and severe) of each treated lesion did not correlate with survival or local treatment failure.

Conclusions. The SIR and the KPS score are prognostic factors in patients whose intracranial breast cancer metastases are treated with GKS. The SIR, which includes the KPS score, patient age, systemic disease status, largest lesion volume, and number of lesions, can be used to identify those patients with breast cancer metastasis who would benefit from GKS better than KPS score alone. The contribution of whole-brain radiation therapy to GKS with regard to local tumor control or survival could not be identified.

Brain Metastases in Patients with Breast Cancer: New Horizons

Brain metastases occur in as many as one third of patients with disseminated breast cancer. In this article, we discuss various presentations of brain metastases from breast cancer and review evidence that supports different treatment options. Because no prospective, randomized, controlled studies, to our knowledge, have focused solely on patients with brain metastases from breast cancer, we will first review retrospective studies of patients with brain metastases from breast cancer. Randomized studies of patients with brain metastases caused by multiple primary cancers will also be examined, and the conclusions from these studies will be extrapolated to patients with breast cancer. Because brain metastases from breast cancer occur in a variety of different clinical settings, ranging from a single metastasis without extensive extracranial disease to multiple brain metastases with widespread extracranial disease, treatment approaches must be tailored to the specific circumstances of each patient. For different clinical scenarios, neurosurgical resection, radiosurgery, and/or whole-brain radiation therapy may be appropriate treatment options. For patients with brain metastases from breast cancer that overexpresses HER2/neu, trastuzumab could alter the natural history of the non-central nervous system (CNS) disease. Therefore, HER2 status could also influence the treatment of brain metastases from breast cancer. Given the prevalence of brain metastases in patients with metastatic breast cancer in contemporary series, the rationale for clinical trials of CNS screening and prophylactic cranial irradiation will be discussed.

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.

Stereotactic radiosurgery for multiple brain metastases from breast carcinoma

BACKGROUND

The current study analyzed the feasibility and outcome of stereotactic radiosurgery (SRS) for treatment of brain metastases from breast carcinoma.

METHODS

During an 8-year period, 151 patients with a combined total of 620 brain metastases from breast carcinoma underwent 197 outpatient SRS procedures. Sixty-three percent of all patients had multiple brain metastases. The median tumor volume was 2.2 cm(3) (range, 0.1-20.9 cm(3)). The mean prescribed tumor dose was 19 +/- 4 grays. Local/distant tumor recurrences were treated with additional radiosurgical therapy for patients with stable systemic disease. All patients were categorized according to the Radiation Therapy Oncology Group classification. Survival time and freedom from local tumor recurrence were analyzed using the Kaplan-Meier method. Prognostic factors were identified using the Cox proportional hazards model.

RESULTS

The overall median survival duration was 10 months after SRS. Ninety-four percent of patients did not experience local brain tumor recurrence after radiosurgery. In addition, 70.2% of patients did not have disease recurrence in the brain. Most patients died of systemically progressing malignancy. A Karnofsky performance score > 70 and recursive partitioning analysis Class I were related to prolonged survival in the univariate and multivariate analyses. Age, whole-brain radiotherapy, surgery, number of metastases, chemotherapy, and latency period from diagnosis of the primary tumor to the development of brain metastases did not reach prognostic relevance in the multivariate model. Patients with RPA I, II, and III survived 34.9, 9.1, and 7.9 months, respectively. There was no treatment related permanent morbidity and mortality. The transient morbidity rate was 17%. Sixteen patients exhibited symptomatic transient complications related to treatment.

CONCLUSIONS

The results of the current study indicate that SRS is a feasible treatment concept for selected patients with multiple brain metastases from breast carcinoma.

Results of whole brain radiotherapy in patients with brain metastases from breast cancer: a retrospective study

PURPOSE

To analyze the factors that affect survival in patients with brain metastases (BM) from breast cancer who were treated with whole brain radiotherapy (WBRT).

METHODS AND MATERIALS

We identified 116 women with breast cancer who were treated with WBRT alone between February 1984 and September 2000. All patients had treatment and follow-up data available in their medical charts, which we extracted for this retrospective study. We evaluated a number of potential predictors of survival after WBRT: age, primary tumor stage, control of primary tumor, presence of other systemic metastases, site of systemic metastases, Karnofsky performance status, Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis class, total dose of WBRT, and number of BM. Eighteen patients received a total dose >3000 cGy and 7 received a partial brain boost.

RESULTS

For the entire cohort, the median survival from the start of WBRT was 4.2 months. The 1-year survival rate was 17%, and the 2-year survival rate was 2%. Using univariate analysis, only Karnofsky performance status (p = 0. 0084), recursive partitioning analysis class (p = 0. 0147), and total WBRT dose (p = 0.0001) were predictive of longer survival. In multivariate analysis, Karnofsky performance status was the only significant predictor.

CONCLUSION

Overall survival in breast cancer patients with BM treated with WBRT is poor. We recommend breast cancer patients with BM be enrolled in prospective trials to improve results.

Fractionated stereotactic radiotherapy: a short review

Currently, optimally precise delivery of intracranial radiotherapy is possible with stereotactic radiosurgery and fractionated stereotactic radiotherapy. We present in this article a review of the underlying basic physical and radiobiological principles of fractionated stereotactic radiotherapy and review the clinical experience for ateriovenus malformations, pituitary adenomas, mengiomas, vestibular schwanomas, low grade astrocytomas, malignant gliomas, and brain metastases.