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Pancreatic pseudocysts are the most common cystic lesions of the pancreas and may complicate acute pancreatitis, chronic pancreatitis, or pancreatic trauma. While the majority of acute pseudocysts resolve spontaneously, few may require drainage. On the other hand, pancreatic cystic tumors, which usually require extirpation, may disguise as pseudocysts. Hence, the distinction between the two entities is crucial for a successful outcome. We conducted this study to highlight the fundamental differences between pancreatic pseudocysts and cystic tumors so that relevant management plans can be devised. We reviewed the data of patients with pancreatic cystic lesions that underwent intervention between June 2007 and December 2010 in our hospital. We identified 9 patients (5 males and 4 females) with a median age of 40 years (range, 30-70 years). Five patients had pseudocysts, 2 had cystic tumors, and 2 had diseases of undetermined pathology. Pancreatic pseudocysts were treated by pseudocystogastrostomy in 2 cases and percutaneous drainage in 3 cases. One case recurred after percutaneous drainage and required pseudocystogastrostomy. The true pancreatic cysts were serous cystadenoma, which was treated by distal pancreatectomy, and mucinous cystadenocarcinoma, which was initially treated by drainage, like a pseudocyst, and then by distal pancreatectomy when its true nature was revealed. We conclude that every effort should be exerted to distinguish between pancreatic pseudocysts and cystic tumors of the pancreas to avoid the serious misjudgement of draining rather than extirpating a pancreatic cystic tumor. Additionally, percutaneous drainage of a pancreatic pseudocyst is a useful adjunct that may substitute for surgical drainage.

Hypoxia, a state of low oxygen, is a common feature of solid tumors and is associated with disease progression as well as resistance to radiotherapy and certain chemotherapeutic drugs. Hypoxic regions in tumors, therefore, represent attractive targets for cancer therapy. To date, five distinct classes of bioreactive prodrugs have been developed to target hypoxic cells in solid tumors. These hypoxia-activated prodrugs, including nitro compounds, N-oxides, quinones, and metal complexes, generally share a common mechanism of activation whereby they are reduced by intracellular oxidoreductases in an oxygen-sensitive manner to form cytotoxins. Several examples including PR-104, TH-302, and EO9 are currently undergoing phase II and phase III clinical evaluation. In this review, we discuss the nature of tumor hypoxia as a therapeutic target, focusing on the development of bioreductive prodrugs. We also describe the current knowledge of how each prodrug class is activated and detail the clinical progress of leading examples.

Both platinum-based doublet chemotherapy (PBC) and epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) prolong the survival of patients with advanced non-small cell lung cancer (NSCLC). In early studies, most patients underwent PBC as first-line treatment, but not all patients could afford EGFR-TKIs as second-line treatment. To understand the impact of PBC and EGFR-TKIs on NSCLC prognosis, we evaluated the association between the receipt of both regimens and overall survival (OS). Using MEDLINE and EMBASE, we identified prospective, randomized, controlled phase III clinical trials in advanced NSCLC that met the inclusion criteria: in general population with advanced NSCLC, the percentage of patients treated with both PBC and EGFR-TKIs was available in the trial and OS was reported. After collecting data from the selected trials, we correlated the percentage of patients treated with both PBC and EGFR-TKIs with the reported OS, using a weighted analysis. Fifteen phase III clinical trials--involving 11,456 adult patients in 32 arms--were included in the analysis, including 6 trials in Asian populations and 9 in non-Asian (predominantly Caucasian) populations. The OS was positively correlated with the percentage of patients treated with both PBC and EGFR-TKIs (r = 0.797, P < 0.001). The correlation was obvious in the trials in Asian populations (r = 0.936, P < 0.001) but was not statistically significant in the trials in predominantly Caucasian populations (r = 0.116, P = 0.588). These results suggest that treatment with PBC and EGFR-TKIs may provide a survival benefit to patients with advanced NSCLC, highlighting the importance of having both modalities available for therapy.

In the research community, resistance to apoptosis is often considered a hallmark of cancer. However, pathologists who diagnose cancer via microscope often see the opposite. Indeed, increased apoptosis and mitosis are usually observed simultaneously in cancerous lesions. Studies have shown that increased apoptosis is associated with cancer aggressiveness and poor clinical outcome. Furthermore, overexpression of Bcl-2, an antiapoptotic protein, is linked with better survival of cancer patients. Conversely, Bax, CD95, Caspase-3, and other apoptosis-inducing proteins have been found to promote carcinogenesis. This notion of the role of apoptosis in cancer is not new; cancer cells were found to be short-lived 88 years ago. Given these observations, resistance to apoptosis should not be considered a hallmark of cancer.

During normal postnatal mammary gland development and adult remodeling related to the menstrual cycle, pregnancy, and lactation, ovarian hormones and peptide growth factors contribute to the delineation of a definite epithelial cell identity. This identity is maintained during cell replication in a heritable but DNA-independent manner. The preservation of cell identity is fundamental, especially when cells must undergo changes in response to intrinsic and extrinsic signals. The maintenance proteins, which are required for cell identity preservation, act epigenetically by regulating gene expression through DNA methylation, histone modification, and chromatin remodeling. Among the maintenance proteins, the Trithorax (TrxG) and Polycomb (PcG) group proteins are the best characterized. In this review, we summarize the structures and activities of the TrxG and PcG complexes and describe their pivotal roles in nuclear estrogen receptor activity. In addition, we provide evidence that perturbations in these epigenetic regulators are involved in disrupting epithelial cell identity, mammary gland remodeling, and breast cancer initiation.

Anti-angiogenic therapy has shown promising but insufficient efficacy on gliomas. Recent studies suggest that vasculogenic mimicry (VM), or the formation of non-endothelial, tumor-cell-lined microvascular channels, occurs in aggressive tumors, including gliomas. There is also evidence of a physiological connection between the endothelial-lined vasculature and VM channels. Tumor cells, by virtue of their high plasticity, can form vessel-like structures themselves, which may function as blood supply networks. Our previous study on gliomas showed that microvessel density was comparably less in VM-positive tumors than in VM-negative tumors. Thus, VM may act as a complement to ensure tumor blood supply, especially in regions with less microvessel density. Patients with VM-positive gliomas survived a shorter period of time than did patients with VM-negative gliomas. Although the detailed molecular mechanisms for VM are not fully understood, glioma stem cells might play a key role, since they are involved in tumor tissue remodeling and contribute to neovascularization via transdifferentiation. In the future, successful treatment of gliomas should involve targeting both VM and angiogenesis. In this review, we summarize the progress and challenges of VM in gliomas.

The biggest challenge in neuro-oncology is the treatment of glioblastoma, which exhibits poor prognosis and is increasing in incidence in an increasing aging population. Diverse treatment strategies aim at maximum cytoreduction and ensuring good quality of life. We discuss multimodal neuronavigation, supra-maximum tumor resection, and the postoperative treatment gap. Multimodal neuronavigation allows the integration of preoperative anatomic and functional data with intraoperative information. This approach includes functional magnetic resonance imaging (MRI) and diffusion tensor imaging in preplanning and ultrasound, computed tomography (CT), MRI and direct (sub)cortical stimulation during surgery. The practice of awake craniotomy decreases postoperative neurologic deficits, and an extensive supra-maximum resection appears to be feasible, even in eloquent areas of the brain. Intraoperative MRI- and fluorescence-guided surgery assist in achieving this goal of supra-maximum resection and have been the subject of an increasing number of reports. Photodynamic therapy and local chemotherapy are properly positioned to bridge the gap between surgery and chemoradiotherapy. The photosensitizer used in fluorescence-guided surgery persists in the remaining peripheral tumor extensions. Additionally, blinded randomized clinical trials showed firm evidence of extra cytoreduction by local chemotherapy in the tumor cavity. The cutting-edge promise is gene therapy although both the delivery and efficacy of the numerous transgenes remain under investigation. Issues such as the choice of (cell) vector, the choice of therapeutic transgene, the optimal route of administration, and biosafety need to be addressed in a systematic way. In this selective review, we present various evidence and promises to improve survival of glioblastoma patients by supra-maximum cytoreduction via local procedures while minimizing the risk of new neurologic deficit.

The current World Health Organization classification system of primary brain tumors is solely based on morphologic criteria. However, there is accumulating evidence that tumors with similar histology have distinct molecular signatures that significantly impact treatment response and survival. Recent practice-changing clinical trials have defined a role for routine assessment of O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation in glioblastoma patients, especially in the elderly, and 1p and 19q codeletions in patients with anaplastic glial tumors. Recently discovered molecular alterations including mutations in IDH-1/2, epidermal growth factor receptor (EGFR), and BRAF also have the potential to become targets for future drug development. This article aims to summarize current knowledge on the molecular biology of high-grade gliomas relevant to daily practice.

Glioblastoma multiforme (GBM) is the most common malignant primary brain tumor in adults. Standard therapeutic approaches provide modest improvement in the progression-free and overall survival, necessitating the investigation of novel therapies. We review the standard treatment options for GBM and evaluate the results obtained in clinical trials for promising novel approaches, including the inhibition of angiogenesis, targeted approaches against molecular pathways, immunotherapies, and local treatment with low voltage electric fields.

Gliomas are malignant primary brain tumors and yet incurable. Palliation and the maintenance or improvement of the patient's quality of life is therefore of main importance. For that reason, health-related quality of life (HRQoL) has become an important outcome measure in clinical trials, next to traditional outcome measures such as overall and progression-free survivals, and radiological response to treatment. HRQoL is a multidimensional concept covering physical, psychological, and social domains, as well as symptoms induced by the disease and its treatment. HRQoL is assessed by using self-reported, validated questionnaires. Various generic HRQoL questionnaires, which can be supplemented with a brain tumor- specific module, are available. Both the tumor and its treatment can have a negative effect on HRQoL. However, treatment with surgery, radiotherapy, chemotherapy, and supportive treatment may also improve patients' HRQoL, in addition to extending survival. It is expected that the impact of HRQoL measurements in both clinical trials and clinical practice will increase. Hence, it is important that HRQoL data are collected, analyzed, and interpreted correctly. Methodological issues such as selection bias and missing data may hamper the interpretation of HRQoL data and should therefore be accounted. In clinical trials, HRQoL can be used to assess the benefits of a new treatment strategy, which should be weighed carefully against the adverse effects of that treatment. In daily clinical practice, HRQoL assessments of an individual patient can be used to inform physicians about the impact of a specific treatment strategy, and it may facilitate the communication between the physicians and the patients.