Her-2 overexpression increases the metastatic outgrowth of breast cancer cells in the brain.

Retrospective studies of breast cancer patients suggest that primary tumor Her-2 overexpression or trastuzumab therapy is associated with a devastating complication: the development of central nervous system (brain) metastases. Herein, we present Her-2 expression trends from resected human brain metastases and data from an experimental brain metastasis assay, both indicative of a functional contribution of Her-2 to brain metastatic colonization. Of 124 archival resected brain metastases from breast cancer patients, 36.2% overexpressed Her-2, indicating an enrichment in the frequency of tumor Her-2 overexpression at this metastatic site. Using quantitative real-time PCR of laser capture microdissected epithelial cells, Her-2 and epidermal growth factor receptor (EGFR) mRNA levels in a cohort of 12 frozen brain metastases were increased up to 5- and 9-fold, respectively, over those of Her-2-amplified primary tumors. Co-overexpression of Her-2 and EGFR was also observed in a subset of brain metastases. We then tested the hypothesis that overexpression of Her-2 increases the colonization of breast cancer cells in the brain in vivo. A subclone of MDA-MB-231 human breast carcinoma cells that selectively metastasizes to brain (231-BR) overexpressed EGFR; 231-BR cells were transfected with low (4- to 8-fold) or high (22- to 28-fold) levels of Her-2. In vivo, in a model of brain metastasis, low or high Her-2-overexpressing 231-BR clones produced comparable numbers of micrometastases in the brain as control transfectants; however, the Her-2 transfectants yielded 3-fold greater large metastases (>50 microm(2); P < 0.001). Our data indicate that Her-2 overexpression increases the outgrowth of metastatic tumor cells in the brain in this model system.

Reactive glia are recruited by highly proliferative brain metastases of breast cancer and promote tumor cell colonization.

Interactions between tumor cells and the microenvironment are crucial to tumor formation and metastasis. The central nervous system serves as a "sanctuary" site for metastasis, resulting in poor prognosis in diagnosed patients. The incidence of brain metastasis is increasing; however, little is known about interactions between the brain and metastatic cells. Brain pathology was examined in an experimental model system of brain metastasis, using a subline of MDA-MB-231 human breast cancer cells. The results were compared with an analysis of sixteen resected human brain metastases of breast cancer. Experimental metastases formed preferentially in specific brain regions, with a distribution similar to clinical cases. In both the 231-BR model, and in human specimens, Ki67 expression indicated that metastases were highly proliferative (approximately 50%). Little apoptosis was observed in either set of tumors. In the model system, metastases elicited a brain inflammatory response, with extensive reactive gliosis surrounding metastases. Similarly, large numbers of glial cells were found within the inner tumor mass of human brain metastases. In vitro co-cultures demonstrated that glia induced a approximately 5-fold increase in metastatic cell proliferation (P<0.001), suggesting that brain tissue secretes factors conducive to tumor cell growth. Molecules used to signal between tumor cells and the surrounding glia could provide a new avenue of therapeutic targets for brain metastases.

p53, BCL-2 and BAX in non-small cell lung cancer brain metastases: a comparison of real-time RT-PCR, ELISA and immunohistochemical techniques.

OBJECTIVES: Metastasis to the brain is a severe and common complication in non-small cell lung cancer (NSCLC). The examination of cell cycle associated genes in these lesions may contribute to the understanding of metastatic growths in the central nervous system. The aim of this study was to evaluate the p53, BCL-2 and BAX mRNA and protein expression in NSCLC brain metastases in comparison with matched primary tumors. METHODS: For quantitative TaqMan real-time reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), fresh frozen tumor specimens from 12 patients with NSCLC brain metastases were available. For immunohistochemical staining, 78 surgically removed NSCLC brain metastases were used. PCR results were analysed using the DeltaDeltaCT method. Staining was analysed using a modified immunoreactive score (IRS). RESULTS: Overall, p53, BCL-2 and BAX expression values in brain metastases and primary tumors showed a wide variety. The comparison of different techniques revealed different findings on the mRNA and protein level. Herein, PCR and ELISA revealed no clear tendencies. In contrast, immunohistochemistry showed significant overexpression of BAX and underexpression of BCL-2 in brain metastases. CONCLUSION: A high variability in the expression of p53, BCL-2 and BAX in NSCLC exists in brain metastases. Immunohistochemistry revealed overexpression of BAX and underexpression of BCL-2 in brain metastases, whereas there were no clear tendencies using PCR and ELISA techniques. More insights into the BAX/BCL-2 interaction are needed before reasonable conclusions can be drawn from the existing data.

Reduced mRNA and protein expression of BCL-2 versus decreased mRNA and increased protein expression of BAX in breast cancer brain metastases: a real-time PCR and immunohistochemical evaluation.

OBJECTIVES: Brain metastases are an increasingly common complication in breast cancer patients. Apoptosis regulating genes are promising candidates for further treatment options. We examined the mRNA and protein expression of p53, BCL-2 and BAX in breast cancer brain metastases versus primary tumors. METHODS: In a two-step approach p53, BCL-2 and BAX mRNA expression in ductal invasive breast cancer brain metastases was examined by: (1) reverse transcription-polymerase chain reaction (RT-PCR) mRNA expression screening (band appearance in relation to an internal standard) and (2) quantitative real-time RT-PCR (CT-values in relation to an internal standard). Protein expression using immunohistochemistry. Results were compared with primary tumors. RESULTS: We found significantly lower BCL-2 mRNA and protein expression in breast cancer brain metastases versus primary tumors. P53 mRNA and protein expression was also lower in metastases. However, this difference was only significant on mRNA but not on the protein level. BAX expression evaluation revealed was contradictory results: mRNA expression was significantly lower whereas protein expression was significantly higher in metastatic lesions. DISCUSSION: The mRNA and protein expression of p53 and BCL-2 seems to be reduced in breast cancer brain metastases. BAX mRNA and protein may be regulated differentially in metastatic lesions.

Reduced metastasis-suppressor gene mRNA-expression in breast cancer brain metastases.

PURPOSE: Brain metastases are an increasingly common complication in breast cancer patients. The Metastasis Suppressor Genes (MSG) Nm23, KISS1, KAI1, BRMS1, and Mkk4 have been associated with the metastatic potential of breast cancer in vitro and in vivo. METHODS: The mRNA expression of Nm23, KISS1, KAI1, BRMS1, and Mkk4 in fresh frozen tissue samples of brain metastases from ductal invasive breast cancer specimens was examined in relation to primary tumors. In a first step, mRNA expression screening was carried out using a semi-quantitative RT-PCR approach, in a second step quantitative real-time RT-PCR was performed on selected specimens. By immunohistochemical staining, gene products were visualized on the protein level. RESULTS: Semi-quantitative RT-PCR revealed reduced mRNA expression of Nm23, KISS1, KAI1, BRMS, and Mkk4 in brain metastases. Results for KISS1, KAI1, BRMS, and Mkk4 were confirmed by real-time RT-PCR. In detail, mRNA expression reduction in breast cancer brain metastases was tenfold. Expression of MSG could be confirmed by immunohistochemical staining on protein level. CONCLUSIONS: Our investigations revealed significantly reduced mRNA expression of metastases suppressor genes KISS1, KAI1, BRMS1, and Mkk4 in breast cancer brain metastasis. Particularly, in the case of KISS1 and Mkk4, an important role for future treatment of patients with breast cancer brain metastatic lesions can be assumed.

Management of tectal glioma in childhood.

Tectal glioma is a topographical diagnosis including tumors of different histology, mainly low-grade astrocytomas. Clinical symptoms are usually associated with increased intracranial pressure. This report discusses the management of this rare tumor in children. Clinical charts of 12 children with tectal glioma treated in our department between 1976 and 2001 were retrospectively reviewed. The mean age at the time of diagnosis was 6.75 years (range, 4 weeks to 16 years). The duration between first symptoms and the diagnosis of tectal glioma was in the range of 2 days to 9 years. Ten patients presented with symptoms associated with increased intracranial pressure, one patient presented with ataxia, and in one case tectal glioma was an incidental finding. First-line therapy was endoscopic third ventriculostomy in 5 cases (42%), ventriculoperitoneal shunting in 6 cases (50%), and combined partial tumor resection and shunting in one case. Histology was obtained in 5 cases (low-grade astrocytoma, n = 4; ependymoma, n = 1). All patients had good neurologic function at the end of follow-up. Tectal glioma represents a distinct subgroup of brainstem tumors associated with a good (or favorable) prognosis. Effective treatment for hydrocephalus is essential; the tumor should be monitored by regular clinical examination and magnetic resonance imaging. Biopsy is warranted in cases with tumor progression.

Glioblastoma multiforme-report of 267 cases treated at a single institution.

OBJECTIVE: Glioblastoma multiforme (GBM) is the most common and most malignant primary brain tumor in adults. We present 267 cases treated at a single institution and discuss clinical characteristics and prognostic factors with regard to the neurosurgical literature. METHODS: Included in this study were 267 patients who underwent craniotomy for newly diagnosed GBM between 1990 and 2001 at our department. Clinical charts and radiographic images were reviewed. Association to patient survival was estimated using log-rank test. RESULTS: Median patient age was 61 years (mean, 59.5; range, 22-86 years), the male-female ratio was 1.2:1. In 35 cases (13.1%) the tumor was multicentric. Most of the tumors were classified as primary GBM (87.6%). During follow-up,72 patients (26.4%) underwent recraniotomy for GBM recurrence and 3 patients (1.1%) developed spinal drop metastases. Overall median survival was 47 weeks (range, 5-305 weeks). The following parameters were significantly associated with prolonged survival: (1) age 61 years or younger, P < .001; (2) Karnofsky performance scale score of 70 or more, P < .001; (3) radiotherapy with a total dose of at least 54 Gy, P < .001; (4) chemotherapy, P < .001; (5) total tumor resection, P = .014; (6) recraniotomy for GBM recurrence, P = .012. CONCLUSIONS: Glioblastoma multiforme remains an important cause of morbidity and mortality from intracranial tumors. The overall prognosis is dismal, although interdisciplinary therapy can significantly prolong survival and allows a small subgroup of patients to survive 3 years or more.

Expression of DNA mismatch repair proteins MLH1, MSH2, and MSH6 in recurrent glioblastoma.

OBJECTIVES: Methylated O6-methylguanin-DNA-methytransferase (MGMT) promoter methylation is associated with survival in patients with glioblastoma. Current evidence suggests that further mismatch repair genes play a pivotal role in the tumor response to treatment. Candidate genes are MLH1, MSH2, and MSH6. Formerly, we found evidence of prognostic impact of MLH1 and MSH6 immunohistochemical expression in a small series of patients with initial glioblastoma. METHODS: Two hundred and eleven patients were included who underwent macroscopically total removal of primary glioblastoma and at least one re-craniotomy for recurrence. Immunohistochemical staining was performed on paraffin-embedded specimens of initial tumors with specific antibodies against MLH1, MSH2, and MSH6. RESULTS were compared to the Ki67 proliferation index and patient survival. Additionally, fresh frozen samples from 16 paired initial and recurrent specimens were examined using real-time reverse transcription polymerase chain reaction (RT-PCR) with specific primers against MLH1, MSH2, and MSH6. RESULTS were compared to MGMT status and survival. RESULTS: (1) Immunohistochemical expression of MSH6 was significantly associated with the Ki67 proliferation index (P<0.001) but not with survival. (2) PCR revealed two patients with increasing expression of MLH1, MLH2, and MSH6 over treatment combined with lacking MGMT methylation. In another two patients, decreased MLH1, MSH2, and MSH6 expression was observed in combination with MGMT promoter methylation. DISCUSSION: Our data indicate that there may be glioblastoma patient subgroups characterized by MMR-expression changes beyond MGMT promoter methylation. The immunohistochemical expression of MLH1, MSH2, and MSH6 in initial glioblastoma is not associated with patient survival.

Cerebral edema leading to decompressive craniectomy: an assessment of the preceding clinical and neuromonitoring trends.

The aim of this study was to examine the pre-operative clinical and neuromonitoring courses in patients with a decompressive craniectomy to assess and to compare clinical and neuromonitoring signs indicating extensive cerebral edema. We conducted a retrospective analysis of the clinical signs and courses of simultaneous monitoring of intracranial pressure (ICP) and cerebral oxygenation (PtiO2) in 26 consecutive patients who were sedated and treated with a decompressive craniectomy due to extensive cerebral edema after aneurysmal subarachnoid hemorrhage (SAH) (n = 20) or severe head injury (SHI) (n = 6). Pathological monitoring trends always preceded clinical deterioration. In 18 of 26 patients extensive cerebral edema was indicated solely by increasing ICP > 20 mmHg or decreasing PtiO2 < 10 mmHg or both. Anisocoria occurred in only 8 of 26 patients. As opposed to SHI patients, 9 of 20 SAH patients showed decreasing PtiO2 as first warning sign clearly before neurological deterioration or ICP increase. This series shows the utility of combined ICP and PtiO2 monitoring in patients who develop extensive cerebral edema. Pathological monitoring trends indicate deterioration prior to clinical signs which offers a wider therapeutical window. PtiO2 monitoring appears to be particularly valuable after aneurysmal SAH as adjunct to ICP monitoring and CT imaging.

Skull metastases: clinical features, differential diagnosis, and review of the literature.

BACKGROUND: Most metastatic skull lesions are asymptomatic, although they can cause severe disability due to compression of dural sinuses and cranial nerves. The authors present current cases of calvarial and skull base metastases. Clinical features are compared to those of primary skull tumors and tumor-like lesions. METHODS: We retrospectively reviewed the charts and radiographic images of 38 patients who underwent surgery for a skull lesion at our department between 1991 and 2001. The literature on skull metastases was reviewed. RESULTS: In 12 cases, histologic examination revealed skull metastases. Eleven patients were known to suffer from cancer at the time of presentation. However, in 5 cases metastatic lesions were the first evidence of disseminated disease. Radical resection was possible in 9 cases. Removal and reconstruction of the infiltrated dura mater was necessary in 5 patients, whereas reconstruction of the bone was required in 8 patients. In comparison to 18 cases with primary skull tumors, patients with skull metastases presented less frequently with a neurologic deficit (3/12 vs. 9/18), reported a shorter history of symptoms (median 2 months vs. 24 months), and were older (median 70 years vs. 51 years). CONCLUSION: Patients presenting with skull metastases are often in an advanced stage of disease, although surgery can relieve symptoms quickly and effectively with low morbidity. In particular, patients with signs of dura infiltration and related neurologic deficit should be offered neurosurgical therapy.

Neuroendoscopy and high-field intraoperative MRI: first experience.

BACKGROUND: To date, information about the use of intraoperative MRI (iMRI) in patients undergoing neuroendoscopic procedures is sparse. The benefit may be (re)definition of neuronavigation, confirmation of fenestrations and biopsies, detection of complications, and redefinition of anatomical changes during the operation. MATERIAL AND METHODS: Our setting consists of a fully integrated high-field 1.5-T MRI into the operating room. The operating room can be functionally divided into (1) the MRI scanner and (2) the operating table outside the 5 Gauss line where ferromagnetic surgical instruments can be used. We included a consecutive series of 11 adult patients who underwent 11 endoscopic operations in the iMRI setting between January 2007 and September 2011. RESULTS: The median age of patients was 54 years (range: 40-69 years). The male-to-female ratio was 4.5:1. Diagnoses leading to endoscopic treatment were aqueductal stenosis (n = 8; caused by tumors in three cases), pineal cyst (n = 1), tumor of the third ventricle (n = 1), and brain abscess with ventriculitis (n = 1). Endoscopic procedures were endoscopic third ventriculostomy with or without tumor biopsy (n = 5), aqueductoplasty (n = 4), tumor biopsy and septostomy (n = 1), and tumor resection (n = 1). All patients were scanned at least once, seven patients twice during surgery. The mean scan time per procedure was 19 minutes. The following sequences were regarded as most useful: T2 axial (placement of catheter, ruling out of complications), T2 sagittal (flow void signal), and true fast imaging (TRUFI) (fenestration defect). CONCLUSIONS: iMRI enables high-resolution imaging immediately after endoscopic operation. The combined use is technically feasible and of potential value in selected cases with complex hydrocephalus. In most of these cases, scanning can be limited to T2 axial, T2 sagittal, and TRUFI MR images.

Ewing sarcoma of the posterior fossa in an adolescent girl.

Medulloblastoma, astrocytoma, and ependymoma represent the most common infratentorial tumors in childhood, while Ewing sarcomas in that localization are extremely rare. A large left infratentorial space-occupying lesion was diagnosed in a 12-year-old girl with signs of increased intracranial pressure. Following total tumor resection, histological and molecular examination revealed Ewing sarcoma with rearranged EWSR-1 gene. The patient achieved complete remission following adjuvant chemotherapy and radiotherapy according to Euro-EWING 2008 treatment protocol. Intracranial Ewing sarcoma, although rare, should be an important differential diagnosis of intracranial tumors in childhood which requires aggressive multimodal treatment.

Profound prevention of experimental brain metastases of breast cancer by temozolomide in an MGMT-dependent manner.

PURPOSE: Brain metastases of breast cancer cause neurocognitive damage and are incurable. We evaluated a role for temozolomide in the prevention of brain metastases of breast cancer in experimental brain metastasis models. EXPERIMENTAL DESIGN: Temozolomide was administered in mice following earlier injection of brain-tropic HER2-positive JIMT-1-BR3 and triple-negative 231-BR-EGFP sublines, the latter with and without expression of O(6)-methylguanine-DNA methyltransferase (MGMT). In addition, the percentage of MGMT-positive tumor cells in 62 patient-matched sets of breast cancer primary tumors and resected brain metastases was determined immunohistochemically. RESULTS: Temozolomide, when dosed at 50, 25, 10, or 5 mg/kg, 5 days per week, beginning 3 days after inoculation, completely prevented the formation of experimental brain metastases from MGMT-negative 231-BR-EGFP cells. At a 1 mg/kg dose, temozolomide prevented 68% of large brain metastases, and was ineffective at a dose of 0.5 mg/kg. When the 50 mg/kg dose was administered beginning on days 18 or 24, temozolomide efficacy was reduced or absent. Temozolomide was ineffective at preventing brain metastases in MGMT-transduced 231-BR-EGFP and MGMT-expressing JIMT-1-BR3 sublines. In 62 patient-matched sets of primary breast tumors and resected brain metastases, 43.5% of the specimens had concordant low MGMT expression, whereas in another 14.5% of sets high MGMT staining in the primary tumor corresponded with low staining in the brain metastasis. CONCLUSIONS: Temozolomide profoundly prevented the outgrowth of experimental brain metastases of breast cancer in an MGMT-dependent manner. These data provide compelling rationale for investigating the preventive efficacy of temozolomide in a clinical setting.

Leptomeningeal metastasis of an intradural malignant peripheral nerve sheath tumor.

Malignant peripheral nerve sheath tumors (MPNST) are defined as any malignant tumor arising from or differentiating towards the peripheral nerve sheath. Intradural MPNST metastases are very rare. We report, to our knowledge, the first case of leptomeningeal metastasis of a MPNST to the spine and intracranial space. A 56-year-old woman with primary intradural MPNST of the S1 nerve root developed leptomeningeal metastases as well as brain metastases 19 months after diagnosis. The patient had a history of non-Hodgkins lymphoma for which she had received irradiation to the spine 15 years prior to this presentation. She had no stigmata of neurofibromatosis type 1. Patients with MPNST may also develop leptomeningeal metastases as demonstrated in this patient with intradural post-radiation MPNST.

Glioblastoma: clinical characteristics, prognostic factors and survival in 492 patients.

OBJECTIVE: Glioblastoma is the most common and most malignant primary brain tumor in adults. The only overall accepted independent prognostic factors are patient age and performance. We present a large single institution patient series examined for prognostic factors using uni- and multivariate survival analysis. METHODS: 492 patients were included who underwent craniotomy for newly diagnosed glioblastoma WHO grade IV between 1990 and 2007 at our department. The association to patient survival was estimated using log-rank test for univariate analysis and cox regression method for multivariate analysis. RESULTS: Median patient age was 62 years (mean: 60.4 years, range: 22-93 years), the male: female ratio was 1.26:1. Primary genesis was found in 91.0% of cases. A multifocal tumor was present in 110 cases (22.4%). The median pre- and post-operative Karnofsky Performance Score was 70. Total tumor resection was performed in 288 cases (58.5%), subtotal removal in 134 cases (27.2%). The following parameters were significantly associated with survival in univariate analysis: age, performance, primary genesis, multifocal tumor, neurological deficit, neuropsychological findings, seizures, incidental finding, total or subtotal resection, radiotherapy, chemotherapy, combined radio-/chemotherapy with temozolomide, re-craniotomy, second tumor in patient history. The following parameters were significantly associated with survival in multivariate analysis: age, performance, multifocal tumor, total or subtotal resection, radiotherapy, chemotherapy, combined radio-/chemotherapy with temozolomide. CONCLUSION: In addition to patient age and performance, we identified multiple lesions and resection status as independent prognostic factors. Radiotherapy, chemotherapy and combined radio-/chemotherapy with temozolomide were significantly associated with prolonged survival.

Neurosurgical treatment of breast cancer metastases to the neurocranium.

Breast cancer metastases to the neurocranium might involve the bone, the dura, or the brain parenchyma. The latter location is the far most common. The annual incidence of brain metastases in patients with breast cancer is in the range of 4-11 per 100.000 persons per year. Symptoms and findings mainly result from the location of the lesion. The diagnostic method of choice is magnetic resonance imaging before and after administration of contrast material. Breast cancer brain metastases present as solid, cystic, or partially cystic lesions with marked contrast enhancement and perilesional edema. The therapeutic option of choice is microsurgical resection whenever possible. Adjuvant treatment includes radiotherapy, radiosurgery, and/or chemotherapy.

The expression of mismatch repair proteins MLH1, MSH2 and MSH6 correlates with the Ki67 proliferation index and survival in patients with recurrent glioblastoma.

OBJECTIVES: There is a growing body of evidence that deficiency of DNA mismatch repair proteins other than O(6)-methylguanine-DNA methyltransferase (MGMT) also contributes to glioblastoma recurrence. We examined the protein expression of MLH1, MSH2 and MSH6 in paired initial and recurrent glioblastoma and compared the results to the Ki67 proliferation index and patient survival. METHODS: Forty-two patients were included who met the following inclusion criteria: (1) histologically confirmed primary glioblastoma; (2) total tumour resection at initial craniotomy; (3) re-craniotomy for recurrence. Immunohistochemical staining was performed using specific monoclonal antibodies against MLH1, MSH2, MSH6 and Ki67. Chi-square test, Wilcoxon test and log-rank test (Cox-Mantel) were used for statistical analysis. RESULTS: In recurrent tumours, MLH1 expression was significantly reduced. MLH1, MSH2 and MSH6 expression in initial lesions was significantly associated with the Ki67 proliferation index. MLH1 and MSH2 expression in recurrent lesions was also significantly associated with the Ki67 proliferation index. MLH1 and MSH6 positivities in initial lesions were indicators of reduced patient survival. DISCUSSION: Our results indicate a potential important role of MLH1 and MSH6 in glioblastoma progression. Specific attention should be given on the role of MLH1 and MSH6 in patients with glioblastoma recurrence during temozolomide treatment.

Expression of metastasis suppressor gene maspin is reduced in breast cancer brain metastases and correlates with the estrogen receptor status.

OBJECTIVES: The suppressor gene maspin (Serpin B5) is a promising candidate for future treatment. We have examined the messenger RNA (mRNA) and protein expression of maspin in normal breast tissue, breast cancer primaries, brain metastases and breast cancer cell lines. Results were compared to hormone receptor expression and proliferation index. METHODS: Maspin mRNA expression was examined by real-time polymerase chain reaction in fresh frozen human samples and breast cancer cell lines MCF-7, T47-D and MDA-MB-231. Maspin protein, estrogen and progesterone receptor expression as well as Ki-67 proliferation index were detected by immunohistochemistry from 16 patients with breast cancer primaries and breast cancer brain metastases. RESULTS: In relation to normal breast tissue, maspin mRNA expression was decreased in primary tumors and again decreased in brain metastases. Normalized C(T) values were 1 (normal tissue), 0.3 (primary tumors) and 0.13 (brain metastases). Immunohistochemistry revealed same tendencies. In comparison to poorly invasive breast cancer cell lines, maspin mRNA expression was decreased in highly invasive and metastatic 231-parental cell lines. In contrast, maspin mRNA expression was increased in 231-brain, and it was not detectable in 231-bone. Patients with maspin-positive primary tumors showed longer survival. DISCUSSION: This finding adds maspin to the list of metastasis suppressor genes possibly involved in the formation of breast cancer brain metastases.