Whole-brain radiation therapy in breast cancer patients with brain metastases

Whole-Brain Radiotherapy Alone vs Preceded by Bevacizumab, Etoposide, and Cisplatin for Untreated Brain Metastases From Breast Cancer: A Randomized Clinical Trial

Importance

The incidence of brain metastasis is increasing in patients with metastatic breast cancer. Treatments to extend the control of brain metastasis are urgently required.

Objective

To investigate whether the addition of an induction treatment of bevacizumab, etoposide, and cisplatin (BEEP) improves brain-specific progression-free survival (PFS) after whole-brain radiotherapy (WBRT).

Design, Setting, and Participants

This open-label, randomized, multicenter clinical trial assessed patients with brain metastases from breast cancer (BMBC) in Taiwan from September 9, 2014, to December 24, 2018, with survival follow-up until December 31, 2021. Key inclusion criteria included metastatic brain tumors not suitable for focal treatment, WBRT naivety, age 20 to 75 years, and at least 1 measurable brain metastatic lesion. The primary end point was brain-specific PFS, with an expected hazard ratio of 0.60, a 2-sided α ≤ .20, and power of 0.8.

Interventions

Eligible patients were randomly assigned at a ratio of 2:1 to the experimental arm, which involved 3 cycles of BEEP followed by WBRT, or the control arm, which involved WBRT alone.

Main Outcomes and Measures

The primary end point was the determination of brain-specific PFS by local investigators according to the Response Evaluation Criteria in Solid Tumors, version 1.1, the initiation of other brain-directed treatment after WBRT, or death. Other key end points included brain-specific objective response rate after 8 weeks of BEEP treatment or WBRT and 8-month brain-specific PFS rate, PFS, and overall survival.

Results

A total of 118 patients with BMBC were randomized, with the intention-to-treat cohort comprising 112 patients. The median age was 56 years (range, 34-71 years), and 61 patients (54.5%) had ERBB2 (formerly HER2 or HER2/neu)-positive disease. The median (range) brain-specific PFS was 8.1 (0.3-29.5) vs 6.5 (0.9-25.5) months in the experimental and control arms, respectively (hazard ratio, 0.71; 95% CI, 0.44-1.13; P = .15; significant at predefined α ≤ .20). The brain-specific objective response rate at 2 months was not significantly different (BEEP treatment vs WBRT, 41.9% vs 52.6%), but the 8-month brain-specific PFS rate was significantly higher in the experimental group (48.7% vs 26.3%; P = .03). Adverse events were generally manageable with prophylactic granulocyte colony-stimulating factor treatment.

Conclusions and Relevance

The findings show that induction BEEP before WBRT may improve the control of BMBC compared with using upfront WBRT, which could address an unmet need for an effective systemic treatment for intractable brain and extracranial metastases from metastatic breast cancer.

Trial Registration

ClinicalTrials.gov Identifier: NCT02185352.

A phase I trial of sorafenib with whole brain radiotherapy (WBRT) in breast cancer patients with brain metastases and a correlative study of FLT-PET brain imaging

PURPOSE

Sorafenib has demonstrated anti-tumor efficacy and radiosensitizing activity preclinically and in breast cancer. We examined sorafenib in combination with whole brain radiotherapy (WBRT) and explored the [18F] 3'deoxy-3'-fluorothymidine (FLT)-PET as a novel brain imaging modality in breast cancer brain metastases.

METHODS

A phase I trial of WBRT + sorafenib was conducted using a 3 + 3 design with safety-expansion cohort. Sorafenib was given daily at the start of WBRT for 21 days. The primary endpoints were to determine a maximum tolerated dose (MTD) and to evaluate safety and toxicity. The secondary endpoint was CNS progression-free survival (CNS-PFS). MacDonald Criteria were used for response assessment with a correlative serial FLT-PET imaging study.

RESULTS

13 pts were evaluable for dose-limiting toxicity (DLT). DLTs were grade 4 increased lipase at 200 mg (n = 1) and grade 3 rash at 400 mg (n = 3). The MTD was 200 mg. The overall response rate was 71%. Median CNS-PFS was 12.8 months (95%CI: 6.7-NR). A total of 15 pts (10 WBRT + sorafenib and 5 WBRT) were enrolled in the FLT-PET study: baseline (n = 15), 7-10 days post WBRT (FU1, n = 14), and an additional 12 week (n = 9). A decline in average SUV_max of ≥ 25% was seen in 9/10 (90%) of WBRT + sorafenib patients and 2/4 (50%) of WBRT only patients.

CONCLUSIONS

Concurrent WBRT and sorafenib appear safe at 200 mg daily dose with clinical activity. CNS response was favorable compared to historical controls. This combination should be considered for further efficacy evaluation. FLT-PET may be useful as an early response imaging tool for brain metastases.

TRIAL AND CLINICAL REGISTRY

Trial registration numbers and dates: NCT01724606 (November 12, 2012) and NCT01621906 (June 18, 2012).

Autophagy-mediated tumor cell survival and progression of breast cancer metastasis to the brain

Brain metastases represent a substantial amount of morbidity and mortality in breast cancer (BC). Metastatic breast tumor cells committed to brain metastases are unique because they escape immune surveillance, can penetrate the blood-brain barrier, and also adapt to the brain tissue microenvironment (TME) for colonization and outgrowth. In addition, dynamic intracellular interactions between metastatic cancer cells and neighboring astrocytes in the brain are thought to play essential roles in brain tumor progression. A better understanding of the above mechanisms will lead to developing more effective therapies for brain metastases. Growing literature suggests autophagy, a conserved lysosomal degradation pathway involved in cellular homeostasis under stressful conditions, plays essential roles in breast tumor metastatic transformation and brain metastases. Cancer cells must adapt under various microenvironmental stresses, such as hypoxia, and nutrient (glucose) deprivation, in order to survive and progress. Clinical studies reveal that tumoral expression of autophagy-related proteins is higher in brain metastasis compared to primary breast tumors. In this review, we outline the molecular mechanisms underlying autophagy-mediated BC cell survival and metastasis to the brain.

Distribution of metastasis in the brain in relation to the hippocampus: a retrospective single-center analysis of 565 metastases in 116 patients

OBJECTIVE

To examine the distribution of brain metastases (BM) in relation to the hippocampus, so as to determine the risk of metastasis in the hippocampus, and thus provide experimental evidence for the hippocampal avoidance (HA) in patients with BM during radiotherapy.

METHODS

(1) For the retrospective analysis of 116 patients diagnosed with malignancies, confirmed as BM, from December 2014 to December 2016 at the First Affiliated Hospital of Bengbu Medical College. We obtained the T1-weighted, postcontrast axial, sagittal, and coronal Magnetic Resonance imaging (MRI) images f the patients, in supine position, using the head restraints and head thermoplastic masks to adjust the positioning, with computed tomography (CT) positioning scan ranging from the head to the mandible (layer thickness: 3 mm). CT and MRI images were fused on a Philips Pinnacle v9.8 treatment planning system;(2) Every metastasis of the 565 metastases was contoured;(3) hippocampus were contoured, and hippocampus with 5 mm expansion envelopes were analyzed;(4) Using the SPSS 16.0 software, we analyzed the relation between the distribution and age, sex, Karnofsky performance status (KPS), primary site, aggregate volume of intracranial metastases and the whole brain. The data were analyzed using a binary logistic regression analysis method, with two-sided P < 0.05 for statistical significance.

RESULTS

In this study, we recruited 116 patients with 565 metastases. Among them, 1.7% (n = 2) had metastases in the hippocampus, and 11.2% (n = 13) had metastases within 5 mm of the hippocampus, of which more than half were patients with non-small cell lung cancer (n = 7). Using a binary logistic regression to analyze the relation between the metastases located within 5 mm of the hippocampus and age (P = 0.395), sex (P = 0.139), KPS (P = 0.724), primary site (P = 0.894), aggregate volume of intracranial metastases (p = 0.093) and the whole brain (p = 0.998), and none of them showed statistically significant difference between them and the metastases location (P>0.05).

CONCLUSION

This study showed a low risk for the perihippocampal metastases (PHM) and no significant correlation between PHM and age, sex, KPS, primary site, aggregate volume of intracranial metastases and the whole brain. Accordingly, it is may be acceptable to avoid the perihippocampal region during whole brain radiotherapy.

The breast graded prognostic assessment is associated with the survival outcomes in breast cancer patients receiving whole brain re-irradiation

INTRODUCTION

Whole brain (WB) re-irradiation for breast cancer patients with progressive brain metastasis after first-course WB radiotherapy (WBRT) is controversial. In this study, we sought to investigate the association between the molecular sub-classifications and breast-specific Graded Prognostic Assessment (GPA, which includes the Karnofsky performance status, molecular subtypes, and age as its indices) and the outcomes of breast cancer patients who received WB re-irradiation.

METHODS

Twenty-three breast cancer patients who received WB re-irradiation for relapsed and progressive intracranial lesions after first-course WBRT between 2004 and 2016 were retrospectively reviewed. Patients were divided according to the 4 molecular subtypes of luminal A/B (hormone receptor [HR]+/human epidermal growth factor receptor 2 [HER2]-), luminal HER2 (HR+/HER2+), HER2 (HR-/HER2+), and triple negative (HR-/HER2-). The clinical and radiological responses and survival rates after WB re-irradiation were analyzed.

RESULTS

At 1 month after WB re-irradiation, 13 of 23 patients (56.5%) exhibited disappearance or alleviation of neurological symptoms. The median survival time after WB re-irradiation was 2.93 months (95% confidence interval [CI], 1.79-4.08). After WB re-irradiation, patients with HER2-negative tumors had poorer median survival times than those with HER2-positive tumors (2.23 vs. 3.0 months, respectively; p = 0.022). Furthermore, patients with high breast GPA scores (2.5-4.0, n = 11) had longer median survivals than those with low-scores (0-2.0, n = 12) after WB re-irradiation (4.37 vs. 1.57 months, respectively; p < 0.005).

CONCLUSIONS

WB re-irradiation may be a feasible treatment option for certain breast cancer patients who develop brain metastatic lesions after first-course WBRT when these lesions are ineligible for radiosurgery or surgery.

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.

Breast cancer brain metastases: Molecular subtype, treatment and survival

BACKGROUND

No clear guidelines exist for management of breast cancer brain metastases (BCBM).

OBJECTIVE

We assessed the relationship between patient and tumor characteristics, treatment, and overall survival (OS).

METHODS

We conducted a retrospective review of 196 patients who received brain radiation for BCBM between 2009-2013 at Mayo Clinic. Primary tumor characteristics were collected, including simplified molecular subtype. Other characteristics included patient's ECOG, number of brain lesions at BCBM diagnosis, and treatment received, including neurosurgery, whole-brain radiation therapy (WBRT), and stereotactic radiosurgery (SRS). The primary endpoint was OS from time of BCBM diagnosis.

RESULTS

Single-variable analysis revealed patients with HER2+ breast cancer had improved OS (HR = 0.6, p = 0.008). Compared to patients with 1-3 brain lesions, the risk of death in patients with leptomeningeal disease was 2.5-fold higher (p = 0.003). Worsening ECOG status was associated with worsening OS. Patients who received SRS and WBRT had improved OS (HR = 0.37, p < 0.001) compared to patients receiving WBRT alone.

CONCLUSIONS

Patients with the best OS had an ECOG of 0, HER2+ disease, and 1-3 brain lesions. The best OS was associated with the combination of neurosurgery and radiation therapy. A comprehensive treatment plan including neurosurgical evaluation and radiation therapy should be considered for patients with BCBM.

Clinical features of brain metastases in breast cancer: an implication for hippocampal-sparing whole-brain radiation therapy

Objective

The objectives of this study were to describe the distribution of brain metastases (BM) in breast cancer patients and investigate the risk factors for perihippocampal metastases (PHM).

Patients and methods

Retrospective analysis of the clinicopathological characteristics and patterns of BM was performed. Associations between clinicopathological characteristics and PHM (the hippocampus plus 5 mm margin) were evaluated using logistic regression analyses.

Results

A total of 1,356 brain metastatic lesions were identified in 192 patients. Patients with 1–3 BM, 4–9 BM, and ≥10 BM accounted for 63.0%, 18.8%, and 18.2%, respectively. There were only 7 (3.6%) patients with hippocampal metastases (HM) and 14 (7.3%) patients with PHM. On logistic regression, the number of BM was an independent risk factor for PHM. Patients with ≥10 BM had a significantly higher risk of PHM compared with those with <10 BM. Breast cancer subtype (BCS) was not associated with PHM. The number of BM was significantly correlated with various BCSs. Patients with hormone receptor (HR)+/human epidermal growth factor receptor 2 (HER2)+, HR−/HER2+, and HR−/HER2− subtypes had a higher probability of ≥10 BM, relative to patients with an HR+/HER2− subtype.

Conclusion

Our study suggests that a low incidence of PHM may be acceptable to perform hippocampal-sparing whole-brain radiation therapy for breast cancer patients. Patients with extensive diffuse metastases (≥10 BM) were associated with higher odds of PHM.

Mutational profiling of brain metastasis from breast cancer: matched pair analysis of targeted sequencing between brain metastasis and primary breast cancer

Although breast cancer is the second most common cause of brain metastasis with a notable increase of incidence, genes that mediate breast cancer brain metastasis (BCBM) are not fully understood. To study the molecular nature of brain metastasis, we performed gene expression profiling of brain metastasis and matched primary breast cancer (BC). We used the Ion AmpliSeq Cancer Panel v2 covering 2,855 mutations from 50 cancer genes to analyze 18 primary BC and 42 BCBM including 15 matched pairs. The most common BCBM subtypes were triple-negative (42.9%) and basal-like (36.6%). In a total of 42 BCBM samples, 32 (76.2%) harbored at least one mutation (median 1, range 0–7 mutations). Frequently detected somatic mutations included TP53 (59.5%), MLH1 (14.3%), PIK3CA (14.3%), and KIT (7.1%). We compared BCBM with patient-matched primary BC specimens. There were no significant differences in mutation profiles between the two groups. Notably, gene expression in BCBM such as TP53, PIK3CA, KIT, MLH1, and RB1 also seemed to be present in primary breast cancers. The TP53 mutation frequency was higher in BCBM than in primary BC (59.5% vs 38.9%, respectively). In conclusion, we found actionable gene alterations in BCBM that were maintained in primary BC. Further studies with functional testing and a delineation of the role of these genes in specific steps of the metastatic process should lead to a better understanding of the biology of metastasis and its susceptibility to treatment.

Preclinical Efficacy of Ado-trastuzumab Emtansine in the Brain Microenvironment

BACKGROUND

Central nervous system (CNS) metastases represent a major problem in the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer because of the disappointing efficacy of HER2-targeted therapies against brain lesions. The antibody-drug conjugate ado-trastuzumab emtansine (T-DM1) has shown efficacy in trastuzumab-resistant systemic breast cancer. Here, we tested the hypothesis that T-DM1 could overcome trastuzumab resistance in murine models of brain metastases.

METHODS

We treated female nude mice bearing BT474 or MDA-MB-361 brain metastases (n = 9-11 per group) or cancer cells grown in organotypic brain slice cultures with trastuzumab or T-DM1 at equivalent or equipotent doses. Using intravital imaging, molecular techniques and histological analysis we determined tumor growth, mouse survival, cancer cell apoptosis and proliferation, tumor drug distribution, and HER2 signaling. Data were analyzed with one-way analysis of variance (ANOVA), Kaplan-Meier analysis, and Coefficient of Determination. All statistical tests were two-sided.

RESULTS

T-DM1 delayed the growth of HER2-positive breast cancer brain metastases compared with trastuzumab. These findings were consistent between HER2-driven and PI3K-driven tumors. The activity of T-DM1 resulted in a survival benefit (median survival for BT474 tumors: 28 days for trastuzumab vs 112 days for T-DM1, hazard ratio = 6.2, 95% confidence interval = 6.1 to 85.84, P < .001). No difference in drug distribution or HER2-signaling was revealed between the two groups. However, T-DM1 led to a statistically significant increase in tumor cell apoptosis (one-way ANOVA for ApopTag, P < .001), which was associated with mitotic catastrophe.

CONCLUSIONS

T-DM1 can overcome resistance to trastuzumab therapy in HER2-driven or PI3K-driven breast cancer brain lesions due to the cytotoxicity of the DM1 component. Clinical investigation of T-DM1 for patients with CNS metastases from HER2-positive breast cancer is warranted.

Antiepileptic drug use improves overall survival in breast cancer patients with brain metastases in the setting of whole brain radiotherapy

BACKGROUND AND PURPOSE

There is mounting evidence that histone deacetylase (HDAC) inhibitors, e.g. valproic acid (VPA), synergize with radiation to improve outcomes in several cancers. This study was conducted to ascertain whether VPA affected outcomes in breast cancer patients with brain metastases treated with whole brain radiotherapy (WBRT).

MATERIALS AND METHODS

Records from 253 breast cancer patients with brain metastases treated with WBRT were reviewed. Data regarding use of all antiepileptic drugs (AEDs) were extracted. Kaplan-Meier survival times were calculated using the date of brain involvement as time zero. Cox proportional hazard models were used to determine the association between patient and tumor characteristics and overall survival (OS).

RESULTS

Median OS for the entire patient cohort was 6 months. Patients receiving VPA (n=20) had a median OS of 11 months versus 5 months for those not receiving VPA (p=0.028). Median OS was 9 months for patients taking any AED (n=101) versus 4 months for those not taking AEDs (p=0.0003). On multivariate analysis both VPA and AED use were associated with improved OS (HR 0.61, p=0.0419; HR 0.59, p=0.0002, respectively).

CONCLUSIONS

This study suggests the use of AEDs, including VPA, is associated with improved OS in breast cancer patients with brain metastases following WBRT.

[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.

Photodynamic therapy: oncologic horizons

Photodynamic therapy (PDT) is a light-based intervention with a long and successful clinical track record for both oncology and non-malignancies. In cancer patients, a photosensitizing agent is intravenously, orally or topically applied and allowed time to preferentially accumulate in the tumor region. Light of the appropriate wavelength and intensity to activate the particular photosensitizer employed is then introduced to the tumor bed. The light energy will activate the photosensitizer, which in the presence of oxygen should allow for creation of the toxic photodynamic reaction generating reactive oxygen species. The photodynamic reaction creates a cascading series of events including initiation of apoptotic and necrotic pathways both in tumor and neovasculature, leading to permanent lesion destruction often with upregulation of the immune system. Cutaneous phototoxicity from unintentional sunlight exposure remains the most common morbidity from PDT. This paper will highlight current research and outcomes from the basic science and clinical applications of oncologic PDT and interpret how these findings may lead to enhanced and refined future PDT.

Oligometastatic breast cancer: a shift from palliative to potentially curative treatment?

A distinctive subset of metastatic breast cancer is represented by the so called 'oligometastatic' disease, characterized by single/few detectable metastatic lesions. A more aggressive multidisciplinary approach can be considered in this patient population: available data report favorable results of 'radical' local therapy for limited metastatic disease at least in a subset of selected patients. Selection bias and the retrospective nature of data do not allow for generalization of the results: the use of such approaches must be individualized and managed within a multidisciplinary team of dedicated specialists. Improvement in surgical and radiation techniques, development of new tools to deliver local chemotherapy, and new procedures (i.e. cryosurgery, laser and microwave ablation) mandate careful evaluation of such single and combined modalities in controlled clinical trials. A more accurate identification of patients with limited metastases and better definition of treatment endpoints will also allow correct patient selection for locally aggressive therapies. This paper focusses on local treatment of the primary tumor and of the most frequent distant disease sites in the presence of oligometastatic disease.

First assessment of whole-brain radiation therapy combined with pemetrexed-based chemotherapy in non-small-cell lung carcinoma: data on safety and efficacy

The folate antimetabolite pemetrexed was approved for the treatment of patients with metastatic nonsquamous non-small-cell lung carcinoma. Its activity on brain metastases makes pemetrexed attractive in combination with whole-brain radiation therapy (WBRT), but it could also potentially increase toxicity. We examined the medical records of 43 consecutive patients with brain metastases from non-small-cell lung carcinoma. Patients received pemetrexed-based chemotherapy at a dose of 500 mg/m. The median total number of pemetrexed-based chemotherapy cycles was 4 (range: 1-28). During the course of chemotherapy, patients received WBRT delivering 30 Gy in 10 fractions (n=34) or 20 Gy in five fractions (n=9). The median follow-up time was 30.5 weeks (range: 1-79 weeks). Intracranial progression was a cause of death in nine patients (20.9%). Clinical benefit of WBRT was reported in 30 patients (69.8%). The best radiological response was a complete response in eight patients (18.6%), a partial response in 16 patients (37.2%), stable disease in 11 patients (25.6%), and progression in four patients (9.3%). A stable intracranial disease until the last follow-up was observed in 26 patients (60.5%). The median estimated overall survival was 31 weeks (95% CI: 24-37 weeks). Most WBRT-related toxicities were low and 21 patients (48.9%) had no reported acute neurological toxicity. One patient developed unexplained encephalopathy 5 weeks after WBRT completion in the context of progressive diffuse brain metastases. The combination of pemetrexed with WBRT led to considerable clinical improvement and tumor responses in most patients. Overall neurological toxicity was rather low. A clinical trial is essential for better analysis of the potential synergistic effects of a drug with radiation and evaluation of neurological toxicity.

Clinical implication of Time To Brain Metastasis (TTBM) according to breast cancer subtypes

The aims of the present study were to investigate how breast cancer (BC) subtypes and treatment affect time to brain metastasis (TTBM). We retrospectively investigated 189 consecutive patients who were diagnosed with brain metastasis (BM) from BC between 2000 and 2009 at Samsung Medical Center. We analyzed TTBM from initial diagnosis of metastatic BC according to subtypes and trastzumab (T) administration before BM diagnosis. The median age of 189 BM patients from BC was 48 years. We divided TTBM into four groups considering BC subtypes and treatment; HR-positive/HER2-negative (n=45), HER2-positive with T before BM development (n=47), HER2-positive without T before BM development (n=39), and TNBC (n=58). The median TTBMs for each group were 17.5 months, 13.7 months, 5.8 months, and 2.9 months, respectively (p<0.001). HER2-positive without T (HR 1.892, p=0.008) and TNBC (HR 1.652, p=0.023) were independently associated with shorter TTBM. In multivariate analysis, HER2-positive without T (hazard ratio 1.725, p=0.002) and TNBC (hazard ratio 1.579, p=0.022) were independent risk factors for worse metastatic OS compared with HR-positive/HER2-negative subtype. TTBMs were shorter in patients with HER2-positive without T and TNBC among BC subtypes. Prospective clinical study for high risk patients for early BM is warranted.

Whole brain radiotherapy: prognostic factors and results of a radiation boost delivered through a conventional linear accelerator

PURPOSE

Assess prognostic factors for overall survival and the potential benefit of a boost in patients treated with whole brain radiation therapy (WBRT).

METHODS AND MATERIALS

From 2002 to 2006, a retrospective analysis was made from 250 unselected consecutive patients with secondary brain metastases from lung cancer, breast cancer and melanoma. Eighteen patients received surgery and were excluded from analysis. Four potential prognostic factors have been studied: primary tumor type, gender, number of metastases and improvement of neurological symptoms after radiation therapy. A subgroup analysis was performed to determine whether an additional boost could potentially improve outcome in patients who presented with less than three metastases, performance status <2, and no surgical resection of their metastasis.

RESULTS

Average follow-up was 10.3 months. Median overall survival was 5.6 months and survival rates at 1 and 2 years were 22.7% and 10%, respectively. Age less than 65 (p<0.01), neurological improvement after WBRT (p<0.01), and presence of less than three metastases were significant factors for overall survival in multivariate analysis. When focusing on the selected subgroup (120 assessable patients), median overall survival was 4.0 months in patients with no radiation boost, versus 8.9 months in patients with radiation boost (p=0.0024).

CONCLUSIONS

Survival and prognostic factors were similar to those found in the literature. Boost delivered after WBRT by a conventional particle accelerator could provide a benefit in selected patients, especially for centers that do not have radiotherapy techniques in stereotactic conditions. This warrants further prospective assessment.