Therapeutic management of metastatic brain tumors

HER2-Positive Breast Cancer-Current Treatment Management and New Therapeutic Methods for Brain Metastasis

Background: Breast cancer can be classified based on the immunohistochemistry (IHC) phenotypes, defined by the presence or absence of the main IHC markers. IHC phenotyping is important as it determines the prognosis and guides treatment. For example, human epidermal growth factor receptor 2 (HER2) overexpression, which triggers cell growth and division, is observed in HER2-positive breast cancer. Methods: The standard treatment is based on trastuzumab plus pertuzumab in combination with taxane chemotherapy. The possibility of developing metastases depends on those phenotypes. Approximately 25-50% of patients with HER2-positive breast cancer experience brain metastases. This aspect is especially important, as 20% of those patients die as a result. Results: Through the years, many advanced therapies have been introduced to treat brain metastases, including whole brain radiotherapy, stereotactic radiosurgery, and a tyrosine kinase inhibitor (TKI), neratinib. Nonetheless, this still remains a therapeutic challenge. Conclusions: In this review, we focus on the treatment and efficiency of therapies targeting HER2-positive breast cancer, mainly concentrating on the current and newly developed treatment options for brain metastases, such as trastuzumab deruxtecan and tucatinib.

Predicting voxel-level dose distributions of single-isocenter volumetric modulated arc therapy treatment plan for multiple brain metastases

Purpose

Brain metastasis is a common, life-threatening neurological problem for patients with cancer. Single-isocenter volumetric modulated arc therapy (VMAT) has been popularly used due to its highly conformal dose and short treatment time. Accurate prediction of its dose distribution can provide a general standard for evaluating the quality of treatment plan. In this study, a deep learning model is applied to the dose prediction of a single-isocenter VMAT treatment plan for radiotherapy of multiple brain metastases.

Method

A U-net with residual networks (U-ResNet) is employed for the task of dose prediction. The deep learning model is first trained from a database consisting of hundreds of historical treatment plans. The 3D dose distribution is then predicted with the input of the CT image and contours of regions of interest (ROIs). A total of 150 single-isocenter VMAT plans for multiple brain metastases are used for training and testing. The model performance is evaluated based on mean absolute error (MAE) and mean absolute differences of multiple dosimetric indexes (DIs), including (D max and D mean) for OARs, (D 98, D 95, D 50, and D 2) for PTVs, homogeneity index, and conformity index. The similarity between the predicted and clinically approved plan dose distribution is also evaluated.

Result

For 20 tested patients, the largest and smallest MAEs are 3.3% ± 3.6% and 1.3% ± 1.5%, respectively. The mean MAE for the 20 tested patients is 2.2% ± 0.7%. The mean absolute differences of D 98, D 95, D 50, and D2 for PTV60, PTV52, PTV50, and PTV40 are less than 2.5%, 3.0%, 2.0%, and 3.0%, respectively. The prediction accuracy of OARs for D max and D mean is within 3.2% and 1.2%, respectively. The average DSC ranges from 0.86 to 1 for all tested patients.

Conclusion

U-ResNet is viable to produce accurate dose distribution that is comparable to those of the clinically approved treatment plans. The predicted results can be used to improve current treatment planning design, plan quality, efficiency, etc.

Multidisciplinary management of HER2-positive breast cancer with brain metastases: An evidence-based pragmatic approach moving from pathophysiology to clinical data

INTRODUCTION

About 30-50 % of stage IV HER2+ breast cancers (BC) will present brain metastases (BMs). Their management is based on both local treatment and systemic therapy. Despite therapeutic advances, BMs still impact on survival and quality of life and the development of more effective systemic therapies represents an unmet clinical need.

MATERIALS AND METHODS

A thorough analysis of the published literature including ongoing clinical trials has been performed, investigating concepts spanning from the pathophysiology of tumor microenvironment to clinical considerations with the aim to summarize the current and future locoregional and systemic strategies.

RESULTS

Different trials have investigated monotherapies and combination treatments, highlighting how the blood-brain barrier (BBB) represents a major problem hindering diffusion and consequently efficacy of such options. Trastuzumab has long been the mainstay of systemic therapy and over the last two decades other HER2-targeted agents including lapatinib, pertuzumab, and trastuzumab emtansine, as well as more recently neratinib, tucatinib, and trastuzumab deruxtecan, have been introduced in clinical practice after showing promising results in randomized controlled trials.

CONCLUSIONS

We ultimately propose an evidence-based treatment algorithm for clinicians treating HER2 + BCs patients with BMs.

Brain metastasis from colorectal cancer: clinical characteristics, timing, survival and prognostic factors

Background: Brain metastasis (BM) from colorectal cancer (CRC) seriously affects the survival and quality of life of patients. However, this disease is not fully understood. It is not clear when follow-up monitoring should be conducted to achieve early diagnosis. Furthermore, the reported prognostic factors have varied among different studies. Our study aims to determine the clinicopathological, survival and prognostic factors, as well as the timing of BM occurrence.Methods: We retrospectively studied the patients with BM from CRC between January 2000 and July 2017. The clinicopathologic features were assessed, and the time from primary tumor surgery and extracranial metastases (lung, liver and bone) to the occurrence of BM was calculated, respectively. Survival time after BM was statistically analyzed. Multivariate Cox analysis was carried out to determine the independent factors that affected survival.Results: 52 patients were analyzed. Most of the patients (86.5%) had combined extracranial metastases when BM was diagnosed, and lung was the commonest extracranial metastasis location. The median time interval from CRC surgery to the diagnosis of BM was 20.5 months, and the median time interval from lung, liver and bone metastases to BM was 7, 5 and 2 months, respectively. After diagnosis of BM, the median survival was 9 months. Extracranial metastases (p =.012) and Karnofsky performance status (p =.025) were independent prognostic factors based on multivariate analysis.Conclusion: BM from colorectal cancer often occur in the late stage, and has an extremely poor prognosis. Identifying the timing of brain metastasis can help to detect this disease early.

The prognostic factors influencing overall survival in uterine cervical cancer with brain metastasis

BACKGROUND/AIMS

The occurrence of brain metastasis (BM) has increased due to improved overall survival (OS) in uterine cervical cancer. However, research about prognostic factors and therapeutic guidelines for BM in uterine cervical cancer remains scarce due to the rarity of BM in this type of cancer. The present study evaluated the clinical characteristics and prognostic factors influencing OS in patients with BM from uterine cervical cancer.

METHODS

A total of 19 BM patients of uterine cervical cancer were analyzed retrospectively from January 1995 to December 2016.

RESULTS

The median and mean OS of all patients was 9.6 and 15.4 months. Treatment (vs. palliative care, p < 0.001), fewer than three regimens of chemotherapy before BM (vs. ≥ 3, p < 0.013), and chemotherapy after BM (vs. absence, p < 0.001) significantly increased the OS time. The Karnofsky performance status ≥ 70 (vs. < 70, p = 0.213), single BM (vs. multiple BM, p = 0.157), and small cell carcinoma (vs. others, p = 0.351) had numerically higher OS than others. Dual therapy (vs. single therapy, p = 0.182; vs. no therapy, p = 0.076) were associated with a longer OS time, but the difference did not reach statistical significance. In addition, the graded prognostic assessment (GPA) appeared to be a better prognostic tool than the recursive partitioning analysis.

CONCLUSION

The results of the present study suggest active multimodal treatment including neurosurgery, radiotherapy, and chemotherapy for BM of uterine cervical cancer with single BM, good performance status, histology of small cell carcinoma, and a better GPA.

Brain tumour differentiation: rapid stratified serum diagnostics via attenuated total reflection Fourier-transform infrared spectroscopy

The ability to diagnose cancer rapidly with high sensitivity and specificity is essential to exploit advances in new treatments to lead significant reductions in mortality and morbidity. Current cancer diagnostic tests observing tissue architecture and specific protein expression for specific cancers suffer from inter-observer variability, poor detection rates and occur when the patient is symptomatic. A new method for the detection of cancer using 1 μl of human serum, attenuated total reflection-Fourier transform infrared spectroscopy and pattern recognition algorithms is reported using a 433 patient dataset (3897 spectra). To the best of our knowledge, we present the largest study on serum mid-infrared spectroscopy for cancer research. We achieve optimum sensitivities and specificities using a Radial Basis Function Support Vector Machine of between 80.0 and 100 % for all strata and identify the major spectral features, hence biochemical components, responsible for the discrimination within each stratum. We assess feature fed-SVM analysis for our cancer versus non-cancer model and achieve 91.5 and 83.0 % sensitivity and specificity respectively. We demonstrate the use of infrared light to provide a spectral signature from human serum to detect, for the first time, cancer versus non-cancer, metastatic cancer versus organ confined, brain cancer severity and the organ of origin of metastatic disease from the same sample enabling stratified diagnostics depending upon the clinical question asked.

A clinical analysis of brain metastasis in gynecologic cancer: a retrospective multi-institute analysis

This study analyzes the clinical characteristics of the brain metastasis (BM) of gynecologic cancer based on the type of cancer. In addition, the study examines the factors influencing the survival. Total 61 BM patients of gynecologic cancer were analyzed retrospectively from January 2000 to December 2012 in terms of clinical and radiological characteristics by using medical and radiological records from three university hospitals. There were 19 (31.1%) uterine cancers, 32 (52.5%) ovarian cancers, and 10 (16.4%) cervical cancers. The mean interval to BM was 25.4 months (21.6 months in ovarian cancer, 27.8 months in uterine cancer, and 33.1 months in cervical cancer). The mean survival from BM was 16.7 months (14.1 months in ovarian cancer, 23.3 months in uterine cancer, and 8.8 months in cervical cancer). According to a multivariate analysis of factors influencing survival, type of primary cancer, Karnofsky performance score, status of primary cancer, recursive partitioning analysis class, and treatment modality, particularly combined therapies, were significantly related to the overall survival. These results suggest that, in addition to traditional prognostic factors in BM, multiple treatment methods such as neurosurgery and combined chemoradiotherapy may play an important role in prolonging the survival for BM patients of gynecologic cancer.

Brain metastasis from gastrointestinal cancers: a systematic review

BACKGROUND

Brain metastases (BM) from the gastrointestinal tract (GIT) cancers are relatively rare. Despite those advances in diagnostic and treatment options, life expectancy and quality of life in these patients are still poor. In this review, we present an overview of the studies which have been previously performed as well as a comprehensive strategy for the assessment and treatment of BM from the GIT cancers.

METHOD

To obtain information on brain metastases from GIT, we performed a systematic review of Medline, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL). The collected data included patient characteristics, primary tumor data and brain metastases data.

RESULT

In our search of the literature, we found 74 studies between 1980 and 2011, which included 2538 patients with brain metastases originated from gastrointestinal cancer. Analysis of available data showed that among 2538 patients who had brain metastases from GIT, a total of 116 patients (4.57%) had esophageal cancer, 148 patients (5.83%) had gastric cancer, 233 patients (9.18%) had liver cancer, 13 patients had pancreas cancer (0.52%) and 2028 patients (79.90%) had colorectal cancer. The total median age of the patients was 58.9 years.

CONCLUSION

Brain metastases have been considered the most common structural neurological complication of systemic cancer. Due to poor prognosis they influence the survival rate as well as the quality of life of the patients. The treatment of cerebral metastasis depends on the patients' situation and the decisions of the treating physicians. The early awareness of a probable metastasis from GI to the brain will have a great influence on treatment outcomes as well as the survival rate and the quality-of-life of the patients.

Treatment of single or multiple brain metastases by hypofractionated stereotactic radiotherapy using helical tomotherapy

This study investigated the clinical outcomes of a 4-fraction stereotactic radiotherapy (SRT) study using helical tomotherapy for brain metastases. Between August 2009 and June 2013, 54 patients with a total of 128 brain metastases underwent SRT using tomotherapy. A total dose of 28 or 28.8 Gy at 80% isodose was administered in 4 fractions for all tumors. The mean gross tumor volume (GTV) was 1.9 cc. Local control (LC) rates at 6, 12, and 18 months were 96%, 91%, and 88%, respectively. The 12-month LC rates for tumors with GTV ≤0.25, >0.25 and ≤1, and >1 cc were 98%, 82%, and 93%, respectively; the rates were 92% for tumors >3 cc and 100% for >10 cc. The 6-month rates for freedom from distant brain failure were 57%, 71%, and 55% for patients with 1, 2, and >3 brain metastases, respectively. No differences were significant. No major complications were observed. The 4-fraction SRT protocol provided excellent tumor control with minimal toxicity. Distant brain failure was not so frequent, even in patients with multiple tumors. The results of the current study warrant a prospective randomized study comparing single-fraction stereotactic radiosurgery (SRS) with SRT in this patient population.

Intraoperative ultrasonography for presumed brain metastases: a case series study

Brain metastases (BM) are one of the most common intracranial tumors and surgical treatment can improve both the functional outcomes and patient survival, particularly when systemic disease is controlled. Image-guided BM resection using intraoperative exams, such as intraoperative ultrasound (IOUS), can lead to better surgical results.

METHODS

To evaluate the use of IOUS for BM resection, 20 consecutive patients were operated using IOUS to locate tumors, identify their anatomical relationships and surgical cavity after resection. Technical difficulties, complications, recurrence and survival rates were noted.

RESULTS

IOUS proved effective for locating, determining borders and defining the anatomical relationships of BM, as well as to identify incomplete tumor resection. No complications related to IOUS were seen.

CONCLUSION

IOUS is a practical supporting method for the resection of BM, but further studies comparing this method with other intraoperative exams are needed to evaluate its actual contribution and reliability.

Brain metastases as the first symptom of lung cancer: a clinical study from an Asian medical center

OBJECTIVE

Brain metastasis as the first symptom of lung cancer is a unique clinical entity. We conducted a retrospective study to investigate the clinical characteristics and survival of patients with lung cancer whose first symptom was brain metastases in an Asian population.

METHODS

A retrospective study of 186 such patients who had been admitted to one institution in China between January 1, 2003 and December 30, 2008 was performed. The following data were collected and analyzed: manifesting signs and symptoms, imaging studies, extracerebral metastases, initial diagnosis, treatment, and patient survival.

RESULTS

This sample population exhibited high rates of misdiagnosis upon initial presentation (46.8 %). Fifty-seven (30.6 %) patients presented with silent extracerebral metastases. Pathologies among this cohort varied, and adenocarcinomas were most commonly observed. Most patients received surgical resection, and some patients had additional whole-brain radiotherapy or stereotactic radiosurgery. The median survival time for the entire cohort was 15 months (95 % confidence interval, 12.9-17.1 months). Survival rates for 1, 2, and 5 years were 58.2, 34.2, and 6.5 %, respectively. The median survival time was 15, 14, 19, and 7 months for the gross total resection, incomplete resection, surgery + whole-brain radiotherapy, and surgery + stereotactic radiosurgery groups, respectively.

CONCLUSIONS

Brain metastasis as the first symptom of lung cancer is a distinct clinical entity. Although overall survival was poor, combined treatments based on surgery for selected patients were reasonable with the exception of a minority who experienced long-term survival.

Clinicopathologic features of brain metastases from gynecologic malignancies: a retrospective study of 139 cases (KCOG-G1001s trial)

OBJECTIVE

Although brain metastases from gynecologic malignancies are rare, such cases have been gradually increasing in number. The aim of the present study was to evaluate the clinicopathologic features and prognostic factors of brain metastases from gynecologic malignancies.

METHODS

Retrospective analysis of 139 patients with brain metastases from gynecologic malignancies was carried out as a multi-institutional study. The clinicophathological data of the patients were collected from medical records.

RESULTS

Median survival time of the patients with brain metastases was 12.5 months for the ovarian cancer group, 6.2 months for the corpus cancer group, and 5.0 months for the cervical cancer group; two-year overall survival rates were 19.7%, 6.1%, and 4.8%, respectively. Multivariate analysis revealed ovarian/tubal/peritoneal origin, KPS >70, single brain metastasis, absence of extracranial disease, cranial surgery, cranial radiotherapy, and chemotherapy to be independent favorable prognostic factors associated with overall survival.

CONCLUSION

It is considered that aggressive multimodal therapy is warranted in the treatment of brain metastases from gynecologic malignancies in carefully selected patients. The present study may provide a platform for the discussion of management strategies in these rare clinical scenarios.

Brain metastases from hepatocellular carcinoma in two Caucasian Australian patients

Hepatocellular carcinoma (HCC) is one of the world's most common malignant cancers. Its incidence is particularly high in Asia and sub-Saharan Africa but, in recent years, significant increases in HCC have been observed in Australia and other Western countries. Therapeutic advances have contributed to improved survival rates in patients with HCC although intracranial metastases are extremely rare. Here we report the first two published Australian cases of brain metastases from HCC, both in Caucasian patients.

Brain metastases from colorectal cancer: the role of surgical resection in selected patients

AIM

Brain metastasis is infrequent in colorectal cancer patients, and the prognosis is poor. In this retrospective study survival and prognostic factors were determined in patients with brain metastasis from colorectal cancer.

METHOD

Between 1997 and 2006, 39 patients with brain metastasis from colorectal cancer who survived more than 1 month were identified. Data were collected with regard to patient characteristics, location and stage of the primary tumour, extent and location of metastatic disease, and treatment modalities used.

RESULTS

Most (79.5%) patients had pulmonary metastases before brain metastasis, and the brain was the site of solitary metastasis in only one patient. The most frequent symptom was weakness [18 (43.6%) patients]. Overall median survival was 5.0 months and the 1- and 2-year survival rates were 21.8 and 9.1%, respectively. Univariate analysis revealed uncontrolled extracranial metastases (P = 0.019), multiple brain lesions (P = 0.026), bilateral brain metastases (P = 0.032) and serum carcinoembryonic antigen levels greater than 5 ng/ml (P = 0.008) to be poor prognostic factors. The median survival after the diagnosis of brain metastasis was significantly longer in patients who underwent surgical resection (15.2 ± 8.0 months) than in those treated by other modalities (P = 0.001). Treatment modality was the only independent prognostic factor for overall survival in patients with brain metastases from colorectal cancers (P = 0.015).

CONCLUSION

Aggressive surgical resection in selected patients with brain metastases from colorectal cancer may prolong survival, even in the presence of extracranial metastatic lesions.

Targeting SRC in glioblastoma tumors and brain metastases: rationale and preclinical studies

Glioblastoma (GBM) is an extremely aggressive, infiltrative tumor with a poor prognosis. The regulatory approval of bevacizumab for recurrent GBM has confirmed that molecularly targeted agents have potential for GBM treatment. Preclinical data showing that SRC and SRC-family kinases (SFKs) mediate intracellular signaling pathways controlling key biologic/oncogenic processes provide a strong rationale for investigating SRC/SFK inhibitors, e.g., dasatinib, in GBM and clinical studies are underway. The activity of these agents against solid tumors suggests that they may also be useful in treating brain metastases. This article reviews the potential for using SRC/SFK inhibitors to treat GBM and brain metastases.

Modern multidisciplinary management of brain metastases

Ideal management of brain metastases (BMs) requires simultaneous control of the existing brain metastasis (local brain control), prevention of future BMs (distant brain control), and control of the systemic cancer (systemic control). Available tools include whole brain radiation therapy (WBRT), surgery, stereotactic radiosurgery (SRS), and systemic therapies, such as chemotherapies, biologic agents, and radiosensitizing agents. Selecting the combination of these tools is highly individualized and is impacted by numerous factors involving the tumor, patient, provider, and evolving evidence. Historically, patients received WBRT, either alone or with local treatments (surgery or SRS). However, concern about the effects of WBRT, coupled with improvements in local control and survival in select patients, with the combination treatment, has led to a reconsideration of the role of WBRT. Additionally, there have been advancements in the efficacy and tolerance of systemic therapies and clarification regarding the relative risks and symptoms of tumor recurrence versus treatment complications. Thankfully, individualizing modern multidisciplinary management for patients with BMs is being aided by numerous recently completed, ongoing, and planned prospective series.

Motexafin gadolinium: a novel radiosensitizer for brain tumors

For a variety of reasons, the management of brain tumors, both primary and metastatic, remains a considerable challenge. As most systemic therapies do not cross the BBB at therapeutic doses, radiation and surgery have played primary roles in the management of these diseases. Despite significant advances in surgical techniques and radiation delivery, outcomes for most adult brain tumors continue to be poor. In an effort to enhance the effects of radiation in the brain, a variety of radiation sensitizers, including motexafin gadolinium, have been investigated. In the following manuscript, we summarize motexafin gadolinium and its role in brain tumors.

Human epidermal growth factor receptor 2-positive breast cancer and central nervous system metastases

PURPOSE

To determine the incidence, outcomes, and current strategies for management of brain metastases in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer.

METHODS

A literature review was performed to obtain data on central nervous system metastases in patients with breast cancer.

RESULTS

HER2 amplification/overexpression is a prognostic and predictive factor for the development of CNS metastases. Autopsy data show that the incidence rate for CNS metastases in patients with breast cancer is approximately 30%; this may be higher (ie, 30% to 50%) in patients with HER2-positive disease. Treatment with trastuzumab is not associated with an increased incidence of CNS metastases. Data from three phase III adjuvant trials showed the incidence was similar between patients who received trastuzumab and those who did not. Furthermore, trastuzumab can significantly improve overall survival in HER2-positive patients who already have CNS metastases compared with patients who do not receive trastuzumab or those who have HER2-negative brain metastases. This survival advantage is conferred via systemic control of the disease. The current standard of care for patients with CNS metastases is whole-brain radiotherapy (WBRT), with or without surgery, or stereotactic radiosurgery. In the future, novel therapies or combinations of therapies may additionally improve survival in these patients.

CONCLUSION

The incidence of CNS metastases in trastuzumab-treated patients is similar to that in all patients with HER2-positive disease. Trastuzumab can improve survival in patients with HER2-positive disease with CNS metastases.

Trastuzumab treatment in patients with breast cancer and metastatic CNS disease

BACKGROUND

Patients with metastatic central nervous system (mCNS) disease progression from breast cancer have a poor prognosis and often develop associated neurological complications. Human epidermal growth factor receptor 2 (HER2)-positivity status increases the risk of developing mCNS disease. Trastuzumab is an mAb that targets HER2 and is known to extend survival across all stages of HER2-positive breast cancer.

DESIGN

This review considers evidence from preclinical and clinical studies examining the value of continuing trastuzumab treatment in patients who develop mCNS disease. A wealth of data from clinical studies showed that trastuzumab prolonged survival in patients with mCNS disease, compared with no trastuzumab treatment, by effectively controlling their non-CNS disease. Trastuzumab has also been shown to penetrate an impaired blood-brain barrier to a limited degree, such as during radiotherapy, and intrathecal delivery of trastuzumab to the central nervous system (CNS) has shown promise. Research efforts are focussing on improving the delivery of trastuzumab to the CNS.

CONCLUSION

Evidence indicates that patients with mCNS disease from HER2-positive breast cancer should continue to receive trastuzumab to control HER2-positive metastases outside the CNS and receive established therapies to control the mCNS disease.

MR imaging-guided cryoablation of metastatic brain tumours: initial experience in six patients

OBJECTIVE

The objective was to evaluate the initial experience and safety of magnetic resonance imaging (MRI)-guided transcranial cryoablation in cystic metastatic brain tumours.

MATERIAL AND METHODS

Seven cystic metastatic brain tumours in six patients were treated with cryoablation. The approval from the local ethics committee and individual patient consent were acquired before the study. Before the procedure the tumours were detected with conventional CT or MRI. The procedure was performed under local anaesthesia and conscious sedation. A 0.23-T open MRI system with optical tracking was used for procedural planning, instrument guidance and procedural monitoring of the ice ball formation. An MR-compatible, argon-based cryoablation system was used. The schedule of follow-up imaging ranged from 12 days to 12 months.

RESULTS

Seven treatment sessions were performed. All the cryoprobes were successfully inserted into the target with one pass. All the patients tolerated the procedure well without experiencing any neurological deficits during the treatment phase or during the immediate post-treatment period. One patient died 12 days after cryoablation.

CONCLUSION

MR-guided and monitored metastasis brain tumour cryoablation is technically feasible and may represent an alternative treatment in selected patients.

Homogeneous MGMT immunoreactivity correlates with an unmethylated MGMT promoter status in brain metastases of various solid tumors

The O(6)-methylguanine-methyltransferase (MGMT) promoter methylation status is a predictive parameter for the response of malignant gliomas to alkylating agents such as temozolomide. First clinical reports on treating brain metastases with temozolomide describe varying effects. This may be due to the fact that MGMT promoter methylation of brain metastases has not yet been explored in depth. Therefore, we assessed MGMT promoter methylation of various brain metastases including those derived from lung (n = 91), breast (n = 72) kidney (n = 49) and from malignant melanomas (n = 113) by methylation-specific polymerase chain reaction (MS-PCR) and MGMT immunoreactivity. Fifty-nine of 199 brain metastases (29.6%) revealed a methylated MGMT promoter. The methylation rate was the highest in brain metastases derived from lung carcinomas (46.5%) followed by those from breast carcinoma (28.8%), malignant melanoma (24.7%) and from renal carcinoma (20%). A significant correlation of homogeneous MGMT-immunoreactivity (>95% MGMT positive tumor cells) and an unmethylated MGMT promoter was found. Promoter methylation was detected in 26 of 61 (43%) tumors lacking MGMT immunoreactivity, in 17 of 63 (27%) metastases with heterogeneous MGMT expression, but only in 5 of 54 brain metastases (9%) showing a homogeneous MGMT immunoreactivity. Our results demonstrate that a significant number of brain metastases reveal a methylated MGMT-promoter. Based on an obvious correlation between homogeneous MGMT immunoreactivity and unmethylated MGMT promoter, we hypothesize that immunohistochemistry for MGMT may be a helpful diagnostic tool to identify those tumors that probably will not benefit from the use of alkylating agents. The discrepancy between promoter methylation and a lack of MGMT immunoreactivity argues for assessing MGMT promoter methylation both by immunohistochemical as well as by molecular approaches for diagnostic purposes.

Cranial irradiation alters the behaviorally induced immediate-early gene arc (activity-regulated cytoskeleton-associated protein)

Therapeutic irradiation of the brain is commonly used to treat brain tumors but can induce cognitive impairments that can severely affect quality of life. The underlying mechanisms responsible for radiation-induced cognitive deficits are unknown but likely involve alterations in neuronal activity. To gain some mechanistic insight into how irradiation may affect hippocampal neurons known to be associated with cognitive function, we quantitatively assessed the molecular distribution of the behaviorally induced immediate-early gene Arc (activity-regulated cytoskeleton-associated protein) at the level of mRNA and the protein. Young adult C57BL/6J mice received whole-brain irradiation with 0 or 10 Gy, and 1 week or 2 months later, exploration of a novel environment was used to induce Arc expression. The fractions of neurons expressing Arc mRNA and Arc protein were detected using fluorescence in situ hybridization and immunocytochemistry, respectively. Our results showed that there was a significant reduction in the percentage of neurons expressing Arc protein 1 week after irradiation, whereas 2 months after irradiation, there was a reduction in the percentage of neurons expressing both Arc mRNA and Arc protein. Importantly, radiation-induced changes in Arc expression were not a result of neuronal cell loss. The changes observed at 2 months were associated with a significant increase in the number of activated microglia, supporting the idea that inflammation may contribute to neuronal dysfunction. These findings are the first to show that local brain irradiation initiates changes in hippocampal neurons that disrupt the activity patterns (Arc expression) associated with neuroplasticity and memory.

Brain metastases from hepatocellular carcinoma: prognostic factors and outcome: brain metastasis from HCC

Brain metastases from hepatocellular carcinoma are extremely rare. The objectives of the current study were to assess the natural history, outcome, and possible prognostic factors in patients with brain metastases from hepatocellular carcinoma. Between 1995 and 2006, 6,919 patients with hepatocellular carcinoma were treated at Yonsei University Health System. Of those, 62 (0.9%) had a diagnosis of brain metastasis. We carried out a retrospective review of these 62 patients and performed a statistical analysis. The median age at the time patients were diagnosed with brain metastasis was 54 years. Forty-seven patients (76%) were male, and 53 patients had hepatitis B. Median time from diagnosis of hepatocellular carcinoma to brain metastasis was 18.2 months, and 5 patients had brain involvement as their initial presentation. Intracranial hemorrhage was frequently associated (54.8%) with brain metastasis. The most common presenting symptoms were motor weakness, mental change, and headache. Metastases were treated with whole-brain radiation therapy (WBRT) alone in 17 patients and gamma knife surgery alone in 10 patients. Six patients underwent surgical resection and 5 patients were treated with surgical resection followed by WBRT. Twenty-four patients (39%) received steroids only. Median survival after diagnosis of brain metastasis was 6.8 weeks (95% confidence interval: 3.8-9.8 weeks). Univariate analysis showed that treatment modality, number of brain lesions, alpha-fetoprotein, ECOG performance score, recursive partitioning analysis (RPA) class, and Child-Pugh classification had a statistically significant impact on survival. In multivariate analysis, treatment modality, number of brain lesions, and Child-Pugh classification were statistically significant prognostic factors for survival. The overall prognosis of patients with brain metastases from hepatocellular carcinoma is extremely poor. Nevertheless, some subsets of patients manifested the most favorable survival criteria (single brain metastasis and good liver function); thus, for at least these patients, treatment may result in an improved survival time.

Treatment Options for Limited or Symptomatic Metastatic Melanoma

Background

Patients who develop metastatic melanoma often have limited effective treatment options. However, a select group of patients will benefit from aggressive surgery or a multidisciplinary approach, depending on the site of metastasis.

Methods

The current literature was reviewed and summarized regarding the collective recommendations for staging and treating patients with metastatic melanoma.

Results

A thorough preoperative staging includes positron-emission tomography, MRI of the brain, and CT of the chest, abdomen, and pelvis. Tumor biology ultimately determines the success of intervention. A long disease-free interval is a good indicator of potential benefit from resection of metastatic disease. If surgery is performed, no less than a complete resection will affect the overall survival of the patient. Surgery and other multimodality treatment options can be used for symptomatic palliation but will not affect survival. Chemotherapy and radiation are often used to control the symptoms of brain and bony metastases but have limited if any impact on survival.

Conclusions

A select group of patients with metastatic melanoma will benefit from aggressive surgery. Identifying which patients will benefit from treatment requires good clinical judgment and a thorough radiologic evaluation to identify the true extent of disease.