Object: The goal of this study was to evaluate the therapeutic impact of the resection of metastatic brain tumor cells infiltrating adjacent brain parenchyma. Methods: Between July 2001 and February 2007, 94 patients (67 males and 27 females, with a mean age of 55.0 ±12.0 years) underwent resection of a single brain metastasis, followed by systemic chemotherapy with or without radiotherapy. In 43 patients with tumors located in noneloquent areas, the authors performed microscopic total resections (MTRs) that included tumor cells infiltrating adjacent brain parenchyma, and they pathologically confirmed during surgery that the resection margins were free of tumor cells (MTR group). In 51 patients with lesions in eloquent locations, gross-total resections (GTRs) were performed without the removal of neighboring brain parenchyma (GTR group). The 2 groups were then compared for local recurrence and survival. Results: The MTR group had better local control of the tumor than did the GTR group; 10 (23.3%) of 43 patients in the MTR group and 22 (43.1%) of 51 patients in the GTR group had a local recurrence (p = 0.04). The median time to tumor progression in the MTR group could not be calculated using the Kaplan-Meier method, whereas it was 11.4 months in the GTR group. The 1- and 2-year respective local recurrence rates were 29.1 and 29.1% in the MTR group and 58.6 and 63.2% in the GTR group (p = 0.01). Multivariate analysis showed that the MTR procedure was associated with a decreased risk of local recurrence (p = 0.003). A Cox regression analysis revealed that the hazard ratio for a local recurrence in the MTR group versus the GTR group was 3.14 (95% CI 1.47–6.72, p = 0.003). There was no significant difference in the local recurrence rate between the MTR group without radiotherapy (10 [30.3%] of 33) and the GTR group with postoperative radiotherapy (5 [26.3%] of 19). Conclusions: The results in this study suggest that MTRs including tumor cells infiltrating adjacent brain parenchyma for a single brain metastasis provide better local tumor control.

Gliomas are associated with high mortality because of their exceedingly invasive character. As these tumors acquire their invasiveness from low-grade tumors, it is very important to understand the detailed molecular mechanisms of invasion onset. Recent evidences suggest the significant role of microRNAs in tumor invasion. Thus, we hypothesized that deregulation of microRNAs may be important for the malignant progression of gliomas. We found that the aberrant expression of miR-21 is responsible for glioma invasion by disrupting the negative feedback circuit of Ras/MAPK signaling, which is mediated by Spry2. Upregulation of miR-21 was triggered by tumor microenvironmental factors such as hyaluronan and growth factors in glioma cells lacking functional phosphatase and tensin homolog (PTEN), but not harboring wild-type PTEN. Consistently with these in vitro results, Spry2 protein levels were significantly decreased in 79.7% of invasive WHO grade II–IV human glioma tissues, but not in non-invasive grade I and normal tissues. The Spry2 protein levels were not correlated with their mRNA levels, but inversely correlated with miR-21 levels. Taken together, these results suggest that the post-transcriptional regulation of Spry2 by miR-21 has an essential role on the malignant progression of human gliomas. Thus, Spry2 may be a novel therapeutic target for treating gliomas.

Gliomas are the most common primary intracranial tumors. Their distinct ability to infiltrate into the extracellular matrix (ECM) of the brain makes it impossible to treat these tumors using surger...

The aim of this report is to provide accurate nationwide epidemiologic data on primary central nervous system (CNS) tumors in Korea. Despite its importance, there are no accurate statistics on primary CNS tumors in Korea. We analyzed primary CNS tumors diagnosed in 2005 from the nationwide registry. Data on primary CNS tumors diagnosed in 2005 were collected from the Korean Central Cancer Registry and the Korean Brain Tumor Society. Crude and age-standardized rates were calculated in terms of gender, age, and histological type. Tumors of uncertain histology were investigated individually at the corresponding hospitals and had their diagnoses confirmed. A total of 5,692 patients diagnosed with primary CNS tumors in 2005 were included in this study. CNS tumors occurred in females more often than in males (female to male, 1.43 : 1). The most common tumor was meningioma (31.2%). Glioblastoma accounted for 30.7% of all gliomas, and 19.3% of all malignant primary CNS tumors. In children under 19 years of age, both germ cell tumor and embryonal/primitive/medulloblastoma were the most common tumors. This article is the first nationwide primary CNS tumor epidemiology report in Korea. Data from this study should provide valuable information regarding the understanding of primary CNS tumors epidemiology in Korea.