Analysis of progression of number and structure of scans performed using PET, PET/ CT and PET/ MRI in the Czech Republic in 2013- 2021.

BACKGROUND: Positron emission tomography (PET) is a state-of-the-art diagnostic method of nuclear medicine, used for diagnostics of many pathological states in the organism, first and foremost in oncological issues. The first analysis of utilization and potential utilization of PET in the Czech Republic was published in 2013. In the following years, there was a sharp increase in a number of PET/CT and PET/MRI scanners in the country; in 2013-2021, it doubled. Simultaneously with the increase in scans performed, the range of available radiopharmaceuticals also broadened. MATERIAL AND METHODS: The study analyses the numbers and structure of PET, PET/CT and PET/MRI scans in the 2013-2021 period, using the pseudonymized data acquired from the General Health Insurance Company of the Czech Republic. The data was evaluated through a series of qualitative and quantitative indicators (number of scans performed, structure of diagnoses, use of different tracers, and availability of a scan for a patient). RESULTS: In the observed interval of time, the number of scans performed practically doubled, both thanks to more scanners installed and more radiopharmaceuticals available. The percentage of oncological and non-oncological scans remains more or less the same. Nevertheless, the regional differences in a number of scans performed persist, as does the availability of the scan for patients. CONCLUSION: PET is still a dynamically developing molecular imaging method in the Czech Republic. The analysis of a number and structure of scans performed offers a priceless overview of the development of the method over the years, in regard to diagnoses, utilization of individual radiopharmaceuticals or geographic distribution of scans performed. The observed findings are a motivation for further analyses.

Comprehensive Genomic Profiling in Predictive Testing of Cancer.

Despite the rapid progress in the field of personalized medicine and the efforts to apply specific treatment strategies to patients based on the presence of pathogenic variants in one, two, or three genes, patient response to the treatment in terms of positive benefit and overall survival remains heterogeneous. However, advances in sequencing and bioinformatics technologies have facilitated the simultaneous examination of somatic variants in tens to thousands of genes in tumor tissue, enabling the determination of personalized management based on the patient's comprehensive genomic profile (CGP). CGP has the potential to enhance clinical decision-making and personalize innovative treatments for individual patients, by providing oncologists with a more comprehensive molecular characterization of tumors. This study aimed to highlight the utility of CGP in routine clinical practice. Here we present three patient cases with various advanced cancer indicated for CGP analysis using a combination of SOPHiA Solid Tumor Solution (STS, 42 genes) for DNA and SOPHiA RNAtarget Oncology Solution (ROS, 45 genes and 17 gene fusions with any random partners) for RNA. We were able to identify actionable genomic alterations in all three cases, thereby presenting valuable information for future management of these patients. This approach has the potential to transform clinical practice and greatly improve patient outcomes in the field of oncology.

Conjugation of microbial-derived gold nanoparticles to different types of nucleic acids: evaluation of transfection efficiency.

In this study, gold nanoparticles produced by eukaryotic cell waste (AuNP), were analyzed as a transfection tool. AuNP were produced by Fusarium oxysporum and analyzed by spectrophotometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). Fourier transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS) were used before and after conjugation with different nucleic acid (NA) types. Graphite furnace atomic absorption spectroscopy (GF-AAS) was used to determine the AuNP concentration. Conjugation was detected by electrophoresis. Confocal microscopy and quantitative real-time PCR (qPCR) were used to assess transfection. TEM, SEM, and EDS showed 25 nm AuNP with round shape. The amount of AuNP was 3.75 ± 0.2 µg/µL and FTIR proved conjugation of all NA types to AuNP. All the samples had a negative charge of - 36 to - 46 mV. Confocal microscopy confirmed internalization of the ssRNA-AuNP into eukaryotic cells and qPCR confirmed release and activity of carried RNA.

Case report Ileal diverticulitis with covered perforation complicated by pulmonary embolism - case report.

Diverticulitis of the ileum is an inflammatory complication of diverticulosis. It is an uncommon cause of acute abdomen that can have a very serious course, leading, for example, to intestinal perforation or bleeding. Imaging findings are very often negative and the true cause of the condition is only revealed peroperatively. In this case report, we present a case of perforated ileal diverticulitis in a patient with bilateral pulmonary embolism. This was the main reason for conservative management in the first period of time. After resolution of the pulmonary embolism, resection of the affected bowel segment was performed at the time of the next attack.

[Glucose, Lactate, NGAL and Coefficient of Energy Balance in Synovial Fluid in Patients with Hip and Knee Prosthetic Joint Infection]. / Stanovení hladiny glukózy, laktátu, NGAL a KEB ve výpotku u infekcí TEP kolen a kyclí.

PURPOSE OF THE STUDY Laboratory methods are central to prosthetic joint infection (PJI) diagnosis. Most research teams focus on detection of specific inflammatory markers, causative pathogens, or on assessment of the tissue response. This study sought to determine the optimal cut-off values and diagnostic performance of selected synovial markers in relation to the diagnosis of hip or knee PJI. The studied markers were synovial level of glucose, lactate, coefficient of energy balance (CEB) and NGAL (neutrophil gelatinase-associated lipocalin). MATERIAL AND METHODS This prospective study includes 89 patients who underwent revision total knee or hip arthroplasty for septic or aseptic reasons in the period from 2014 to 2017. Among these 89 patients, there are 2 cases of prosthetic hip infection, 22 cases of prosthetic knee infection, 31 aseptic revision total hip arthroplasties and 34 aseptic revision total knee arthroplasties. The diagnostic characteristics of the studied methods were set in relation to the reference standard, the 2013 MSIS (Musculoskeletal Infection Society) criteria. The cut-off values were calculated using the ROC (receiver operating characteristic curve) analysis. RESULTS The synovial glucose test is considered positive if the glucose level drops below 2.65 mmol/L. The area under the curve is 0.813, sensitivity 75.0%, specificity 83.1%. The synovial lactate test is considered positive if lactate level rises above 8.87 mmol/L. The area under the curve is 0.882, sensitivity 70.8%, specificity 95.4%. Synovial NGAL is considered positive if its level exceeds 998 µg/L. The area under the curve is 1.000, sensitivity 100.0%, specificity 100.0%. CEB is considered positive if its value is lower than +4.665. The area under the curve is 0.883, sensitivity 91.7% and specificity 69.8%. Combining of these tests with other synovial markers does not improve the diagnostic performance of the studied tests. CONCLUSIONS The glucose and lactate levels and CEB undoubtedly reflect the presence of an inflammatory process in a prosthetic joint. However, the diagnostic characteristics of these tests are not better than those of other modern diagnostic techniques. As opposed to these tests, synovial NGAL shows excellent diagnostic performance. Nonetheless, the potential of this method shall be verified on larger cohorts of patients. Key words: prosthetic joint infection, periprosthetic infection, total knee arthroplasty, total hip arthroplasty, diagnosis, glucose, lactate, CEB, NGAL.

Appendiceal mucocele - a radiologists view.

Appendiceal mucocele is an obstructive dilatation of the appendix, which results from the filling of its lumen with mucus. This is a rare condition that is asymptomatic in half of the patients. Its severity depends on the cause of appendiceal dilatation. In a small percentage of cases, the dilated appendix ruptures, leading to the development of serious complication; this is termed as pseudomyxoma peritonei. Due to the possibility of malignant etiology of the mucocele, surgical resection remains an essential part of the treatment.

Quality of life after transanal total mesorectal excision - our experience.

INTRODUCTION: Functional outcomes and quality of life (QoL) after transanal total mesorectal excision (TaTME) are very important factors in the evaluation of TaTME in comparison with other approaches to TME. The most common functional problems after resection of the rectum include bowel, urologic and sexual dysfunctions. In this study, we present our experience with QoL after TaTME; the results are compared with worldwide literature in the discussion. METHODS: QoL was assessed by a questionnaire. The total of 54 patients were analysed. A general questionnaire for oncological diseases was used - European Organisation for Research and Treatment of Cancer (EORTC)-QLQ-C30, together with EORTC-QLQ-CR29 - a specific questionnaire for colorectal cancer. The Low Anterior Resection Syndrome (LARS) score was also obtained in all patients. Mean follow-up was 42.65 months (range 9-91 months). RESULTS: The mean LARS score in patients undergoing TaTME was 30.7 while a major LARS was observed in 64.2% of those with LARS. Of all of the symptoms in the EORTC-QLQ-C30 survey, the most serious problems which affected patients undergoing TaTME were diarrhoea (30.25), fatigue (23.87) and insomnia (20.37). In the QLQ-CR29 survey the problems included flatulence (50.94), faecal incontinence (45.06) and stool frequency (35.19). The results of EORTC-QLQ-C30 and QLQ-CR29 are quite heterogeneous. CONCLUSION: In this study the QoL of patients with advanced rectal tumours (of whom 81.5% received neoadjuvant therapy) undergoing TaTME is comparable to results in the current literature. The most severe symptoms affecting QoL after TaTME are flatulence, faecal incontinence, and stool frequency. Other serious symptoms include fatigue and insomnia. LARS was recorded in 73.6% of patients undergoing TaTME, mostly a major LARS.

Why predict climate hazards if we need to understand impacts? Putting humans back into the drought equation.

Virtually all climate monitoring and forecasting efforts concentrate on hazards rather than on impacts, while the latter are a priority for planning emergency activities and for the evaluation of mitigation strategies. Effective disaster risk management strategies need to consider the prevailing "human terrain" to predict who is at risk and how communities will be affected. There has been little effort to align the spatiotemporal granularity of socioeconomic assessments with the granularity of weather or climate monitoring. The lack of a high-resolution socioeconomic baseline leaves methodical approaches like machine learning virtually untapped for pattern recognition of extreme climate impacts on livelihood conditions. While the request for "better" socioeconomic data is not new, we highlight the need to collect and analyze environmental and socioeconomic data together and discuss novel strategies for coordinated data collection via mobile technologies from a drought risk management perspective. A better temporal, spatial, and contextual understanding of socioeconomic impacts of extreme climate conditions will help to establish complex causal pathways and quantitative proof about climate-attributable livelihood impacts. Such considerations are particularly important in the context of the latest big data-driven initiatives, such as the World Bank's Famine Action Mechanism (FAM).

Our experience with transanal total mesorectal excision (TaTME) procedures in middle and distal rectal tumors.

INTRODUCTION: Transanal total mesorectal excision (TaTME) is a relatively new approach in surgical treatment of rectal cancer. There are no clear indications when to choose this strategy. It is a technically demanding procedure for the surgeon with a long learning curve, which should also be taken into account in evaluation of this method. The results of both oncological and postoperative complications must be properly evaluated to explore the benefit of TaTME. The aim of this study is to assess the potential benefit of TaTME compared to other alternatives in middle and distal rectal tumors. METHODS: Retrospective evaluation of patients undergoing TaTME procedure performed by one team of surgeons between October 2014 and June 2019. The authors analyzed demographic indicators of the group of patients, tumor characteristics, specimen quality, early postoperative complications and the possibility of stoma reversal. RESULTS: A total of 93 patients underwent TaTME procedure for middle and distal rectal cancer. Mean BMI was 27.6 (4.8). T3 or T4 tumor was found in 73 (78.5%) patients, 68 (73.1%) patients had positive lymph nodes and 12 (12.9%) patients were treated for synchronous metastatic rectal cancer. Neoadjuvant therapy was used in 80 (86%) patients. Conversion to open laparotomy was necessary in one case (1%). Stapled anastomosis was performed in 37 (39.7%) cases, handsewn in 56 (60.2%). A positive circumferential resection margin (CRM) was found in 10 (10.7%) cases. Distal resection margin (DRM) was positive in 3 (3.2%) patients. Pathological analysis showed a complete mesorectum in 18 patients (19.4%), nearly complete in 39 (41.9%) and an incomplete mesorectum in 36 (38.7%). Complications in the first 30 days after primary surgery were observed in 38 (40.8%) patients, mainly for anastomotic leak (19 patients, 20.4%). Reoperation was required in 7 (7.5%) patients. Permanent colostomy had to be performed in 4 (4.3%) cases. No patient died after surgery. CONCLUSION: In a selected group of patients it is possible to perform resection using this approach with acceptable postoperative morbidity and quality of the specimen. We used TaTME procedure in patients expected to have difficult TME due to obesity, size and distal localization of tumor. The incidence of conversion to open surgery was very low. Further studies for long term oncological outcomes are needed.

Different chromosome damage in lymphocytes of newly diagnosed gastrointestinal and breast cancer patients.

Structural chromosome aberrations are a predictive biomarker of cancer risk. Conventional chromosome analysis widely used for these purposes detects unstable chromosome aberrations that are eliminated during cell division. Stable aberrations that may persist in the body and tend to accumulate during a lifetime can be detected by fluorescence in situ hybridization (FISH). The aim of the study was to investigate the level of chromosome damage in newly diagnosed cancer patients and control subjects by FISH. Both groups of untreated cancer patients had increased frequency of aberrant cells. However, chromosome damage affected different cytogenetic endpoints. Stable translocations and cells with complex rearrangements were elevated in breast cancer patients whereas unstable chromosome aberrations (dicentric chromosomes and acentric fragments) were elevated in gastrointestinal cancer patients. These associations observed in nonsmokers were typically not pronounced in smokers (with the exception of dicentric chromosomes in gastrointestinal patients). Exposure to tobacco smoke increased aberrations in healthy controls but not in the cancer patients. Our study suggests an association between cancer and stable chromosomal rearrangements in breast cancer patients. Unstable aberrations elevated in gastrointestinal cancer patients may be at least partly ascribed to the exposure to diagnostic X-rays.

Increasing procoagulant activity of circulating microparticles in patients living with HIV.

OBJECTIVES: HIV-infected individuals are at higher risk of non-AIDS diseases associated with procoagulant status. Microparticles are elevated in disorders associated with thrombosis (e.g., cardiovascular diseases). We investigated the association between microparticle levels in untreated and treated HIV-infected subjects, and determined the association with immune status, viral replication, and duration of antiretroviral therapy. PATIENTS AND METHODS: We included 144 HIV-infected subjects, including 123 on antiretroviral therapy (ART) and 21 before treatment initiation. A control group of 40 HIV-negative healthy adults matched for age and sex was used for comparison of microparticle levels. Treated subjects were divided into five groups depending on the period of antiretroviral exposure. Statistically significant differences were determined by Kruskal-Wallis test and Chi2 test. The relation between microparticles and other parameters was assessed using Spearman's coefficient of correlation. RESULTS: Microparticle levels were significantly higher in treated and untreated HIV-infected subjects than in non-HIV-infected controls (P<0.001). The microparticle level was similar between the groups on treatment (P=0.913). No association between the microparticle level and CD4+ count, CD4+/CD8+ ratio, number of HIV-1 RNA copies, or duration of exposure to antiretroviral treatment was observed. CONCLUSION: Increased levels of microparticles may be due to processes independent of viral replication and CD4+ cell count, and microparticle release might persist even during viral suppression by antiretroviral treatment. Elevated microparticle levels might occur in response to other triggers.

Use of preperitoneal wound catheter for continuous local anaesthesia after laparoscopic colorectal surgery.

INTRODUCTION: The main cause of postoperative pain after abdominal surgery is the wound where laparotomy is made. Recently, laparoscopic procedures have become common in colorectal surgery. Although improving the tolerance of the surgery, postoperative pain management still remains a discussed problem. The use of an epidural catheter used to be generally recommended in the open surgery era; however, an ideal strategy for postoperative analgesic therapy after laparoscopy remains unclear. Reduced administration of opioid analgesic drugs after colorectal resection is a generally accepted goal. Preperitoneal catheter insertion for continuous local anaesthetic (LA) infusion in the wound after surgery is a simple alternative to other pain management methods. METHODS: Retrospective analysis of analgotherapy outcomes in patients undergoing laparoscopic colorectal resection procedures, divided in three patient groups according to the type of analgesia: Group 1: use of a catheter for local wound infusion (KAT) n=73; group 2: epidural analgesia (EPI) n=23; and control group 3 with combined parenteral and subcutaneous analgesia (CON) n=66. The main objective of this study was to analyse postoperative pain and the consumption of opioid analgesics in the first three days from the surgery and the incidence of any complications related to the analgesic therapy. RESULTS: Opioid consumption in KAT and EPI groups was significantly lower compared to CON in the first 72 hours from the surgery. The lowest postoperative pain was measured in the EPI group. Subjective perception of pain, measured using VAS, was not significantly different between the KAT and CON groups. In KAT patients, vomiting was statistically less frequent than in CON patients. There was no significantly different incidence of paralytic ileus in the KAT and CON groups and no paralytic ileus was observed in the EPI group. There was no increased incidence of SSI (surgical site infections) in the KAT group compared to the other groups. CONCLUSION: The use of the catheter was assessed as safe. Insertion and management of the catheter is unsophisticated, and we did not observe any complications in terms of application of the catheter or toxic side effects of the LA. The use of the catheter clearly reduced opioid administration in the postoperative period compared to the control group (CON) with combined parenteral and subcutaneous analgesics. The best pain control measured using the visual analog scale (VAS) was observed in the EPI group.

Synthetic Lethality - Its Current Application and Potential in Oncological Treatment.

BACKGROUND: Synthetic lethality is a gene interaction where a defect in one of the interacting genes is compatible with cell viability, whereas the disruption of both genes leads to cell death. The discovery of the lethal effect of poly(ADP-ribose) polymerase (PARP) inhibitors in BRCA1/2 mutant cells has opened an important direction in the development of targeted therapy in oncology. The PARP inhibitor olaparib has become the first registered drug for recurrent high-grade serous ovarian cancer treatment based on synthetic lethality that has reached the clinic. Current research focuses on the combination of PARP inhibitors and inhibitors of kinases, which control the cell cycle, to prevent or overcome resistance to PARP inhibitors. There are also ongoing clinical trials which examine PARP inhibitor treatment in other types of cancers including tumours presenting the so-called BRCAness phenotype. Screenings for new synthetic lethalities which could serve as potential targets for new drug development have improved with the CRISPR/Cas9 technology, but another key problem persists in the screening efforts, namely the incomplete penetrance of synthetic lethality throughout a tumour cell population. PURPOSE: This paper summarises the current application of synthetic lethality principles in oncology and discusses the challenges in research focused on potential new drugs based on synthetic lethality.

Flow Cytometric Analysis of Nucleoside Transporters Activity in Chemoresistant Prostate Cancer Model.

BACKGROUND: Nucleoside analogues represent a relevant class of antimetabolites used for therapy of various types of cancer. However, their effectivity is limited by drug resistance. The nucleoside transport capability of tumour cells is considered to be a determinant of the clinical outcome of treatment regimens using antimetabolites. Due to hydrophilic properties of antimetabolites, their transport across the plasma membrane is mediated by two families of transmembrane proteins, the SLC28 family of cation-linked concentrative nucleoside transporters (hCNTs) and SLC29 family of energy-independent equilibrative nucleoside transporters (hENTs). Loss of functional nucleoside transporters has been associated with reduced efficacy of antimetabolites and their derivatives and treatment failure in diverse malignancies including solid tumours, such as pancreatic adenocarcinoma. MATERIAL AND METHODS: The effectivity and kinetics of antimetabolite uptake were analysed using control and docetaxel-resistant PC3 cells. For this purpose, fluorescent nucleoside analogue probe uridine-furane and inhibitor of nucleoside transporters, S-(4-nitrobenzyl) -6-thioinosine were exploited. Combination of flow cytometry, confocal microscopy and real-time quantitative polymerase chain reaction methodology were used for the analysis. RESULTS: Here we utilized flow cytometric assay for analysis of nucleoside transporters activity employing fluorescent nucleoside analogue, uridine-furane. We have determined the long-time kinetics of uridine-furane incorporation and quantified its levels in the parental prostate cancer cell line PC3 and its chemoresistant derivative. Finally, we have shown an association between the activity and mRNA expression of nucleoside transporters and sensitivity to various nucleoside analogues. CONCLUSION: Fluorescent techniques can serve as an effective tool for the detection of nucleoside transporter activity which has the potential for application in clinical oncology.Key words: nucleoside transporter proteins - drug resistance - prostatic neoplasm - chemotherapy.

[Pilot Study on MicroRNAs as Biomarkers of Response to Sunitinib Treatment in Patients with Metastatic Renall Cell Carcinoma]. / MikroRNA jako biomarkery odpovedi na lécbu sunitinibem u pacientu s metastatickým karcinomem ledvin - pilotní studie.

BACKGROUND: Renal cell carcinoma (RCC) accounts for 2-3% of all malignant tumours. Metastatic RCC (mRCC) is commonly treated with tyrosine kinase inhibitors (TKI). Effective TKIs administration can be achieved only by accurate prediction of therapeutical response. Therefore, the aim of this study was to analyse papers concerning predictive potential of microRNA (miRNA). MATERIAL AND METHODS: We chose seven candidate miRNAs and analysed their expression on 44 patients divided into cohort with poor and good response to sunitinib treatment. Patients were divided into two groups according to progression-free survival. RNA from tissue samples was isolated and expression of selected miRNAs was measured using quantitative PCR with miRNA-specific TaqMan probes. RESULTS: We successfully validated two miRNAs to be differentially expressed in responding and non-responding patients to sunitinib treatment. Other analysed miRNAs have not shown predictive potential. CONCLUSION: From miRNAs studied so far, two miRNAs had predictive value according to present study.Key words: microRNA - renal cell carcinoma - sunitib The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Supported by Ministry of Health of the Czech Republic, grant No. 15-34678A. All rights reserved.Submitted: 19. 3. 2018Accepted: 20. 3. 2018.

[Biomonitoring of Work with Genotoxic Substances and Factors in a Cancer Treatment Facility]. / Biomonitoring práce s genotoxickými látkami a faktory v onkologickém zdravotnickém zarízení.

BACKGROUND: A long-term occupational exposure of healthcare staff to cytostatics and ionizing radiation is associated with a possible manifestation of their genotoxic, carcinogenic and teratogenic effects. MATERIAL AND METHODS: A total number of 101 employees working with cytostatics or ionizing radiation were examined (some of them repeatedly) in a cancer treatment facility. The control group consisted of 119 persons excluded from the risk exposure. Fluorescence in situ hybridization with three pairs of whole-chromosomal probes and a pancrossomeric probe was used and the translocation frequency was determined. RESULTS: The total number of chromosomal rearrangements of healthcare professionals and control group correlates with age. Taking into account the age dependence, an increased level of chromosomal reconstruction was found in the case of 11 individuals, 10 of which were female, working on the positions of pharmacist, general nurse, physician. A total of 9 of those case involved the work with cytostatics. Five of these cases were re-examined two years later and the observed levels dropped to the control level. CONCLUSION: The results of biomonitoring should be evaluated on a group basis and individually, taking into account the personal history and possible non-professional effects on individuals - in particular those related to specific environmental measurement results.Key words: preventive medicine - occupational exposure - cytostatic agents - chromosome aberrations - in situ hybridization - fluorescence The authors declare they have no potential conflicts of interest concern ing drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. This work was supported by project of Ministry of Health Czech Republic. reg. No. 15-33968A.Submitted: 12. 4. 2018Accepted: 16. 4. 2018.

[Experimental processing of corrosion casts of large animal organs]. / Experimentální príprava korozivních preparátu orgánu velkého zvírete.

INTRODUCTION: Corrosion casts (CCs) are used for the visualization and assessment of hollow structures. CCs with filled capillaries enable (with the help of imaging methods) to obtain data for mathematical organ perfusion modelling. As the processing is more difficult in case of organs with greater volume of the vasculature, mainly organs from small animals have been cast up to now. The aim of this study was to optimize the protocol of corrosion casting of different organs of pig. Porcine organs are relatively easily accessible and frequently used in experimental medicine. METHOD: Organs from 10 healthy Prestice Black-Pied pigs (6 females, body weight 35-45 kg), were used in this study (liver, spleen, kidneys and small intestine). The organs were dissected, heparin was administered into the systemic circulation and then the vascular bed of the organs was flushed with heparinized saline either in situ (liver) or after their removal (spleen, kidney, small intestine). All handling was done under the water surface to prevent air embolization. The next step was an intraarterial (in case of the liver also intraportal) administration of Biodur E20® (Heidelberg, Germany) resin. After hardening of the resin the organ tissue was dissolved by 15% KOH and the specimen was rinsed with tap water. Voluminous casts were stored in 70% denatured alcohol, the smaller ones were lyophilized. The casts were assessed with a stereomicroscope, computed and microcomputed tomography (CT and microCT), a scanning electron microscope (SEM) and high-resolution digital microscope (HRDM). RESULTS: High-quality CCs of the porcine liver, kidneys, spleen and small intestine were created owing to the sophisticated organ harvesting, the suitable resin and casting procedure. Macroscopic clarity was improved thanks to the possibility of resin dying. Scanning by CT was performed and showed to be a suitable method for the liver cast examination. MicroCT, SEM and HRDM produced images of the most detailed structures of vascular bed. Despite the fact that SEM seems to be an irreplaceable method for CCs quality control, it seems that this modality could be partly replaced by HRDM. MicroCT enabled to obtain data about three-dimensional layout of the vascular bed and data for mathematical modelling of organ perfusion. With regard to the quality of the CCs, they could also be used to teach human anatomy. CONCLUSIONS: The protocol of the corrosion casting of the porcine liver, kidneys, spleen and small intestine CCs was optimized. Thanks to different imaging methods, the CCs can be used as a source of data on three-dimensional architecture of the vascular bed. These data can be used for mathematical modeling of organ perfusion which can be helpful for example for optimization of organ resections.Key words: corrosion casts microvasculature Biodur E20® domestic pig animal model.

MicroRNAs as outcome predictors in patients with metastatic colorectal cancer treated with bevacizumab in combination with FOLFOX.

Bevacizumab is a humanized anti-vascular endothelial growth factor monoclonal antibody, used in combination with a oxaliplatin-based chemotherapy in the treatment of metastatic colorectal cancer (mCRC). The aim of the present study was to identify microRNA (miRNA)-based predictive biomarkers of therapy response in order to avoid unnecessary and costly therapy to non-responding patients. High-throughput miRNA microarray profiling (Affymetrix miRNA array) was performed on a discovery cohort of patients with mCRC. The discovery cohort was (n=20) divided into either responding (n=10) or non-responding (n=10) groups of bevacizumab/5-flourouracil, leucovorin, oxaliplatin (FOLFOX) treatment according to Response Evaluation Criteria in Solid Tumors criteria. Validation of candidate miRNAs was performed on an independent cohort of 41 patients with mCRC using quantitative reverse transcription polymerase chain reaction. Normalized data were subjected to receiver operating characteristic and Kaplan-Meier analyses. In total, 67 miRNAs were identified to be differentially expressed when miRNA expression was compared between responding and non-responding patients to bevacizumab/FOLFOX treatment (P<0.05). A total of 7 miRNAs were chosen for independent validation, which confirmed significantly higher expression of miR-92b-3p, miR-3156-5p, miR-10a-5p and miR-125a-5p (P<0.005) in tumor tissue of responding patients compared with non-reponding patients. Using the combination of miRNAs, the present study identified responders to the therapy with sensitivity 82% and specificity 64% (area under the curve = 0.8015). In conclusion, 4 predictive miRNAs associated with progression-free survival (PFS) were identified in patients with mCRC treated with bevacizumab/FOLFOX. Following further independent validations, detection of these miRNA may enable identification of patients with mCRC who may potentially benefit from the therapy.

[Current Possibilities for Predicting Responses to EGFR Blockade in Metastatic Colorectal Cancer]. / Soucasné moznosti predikce odpovedi na cílenou anti-EGFR lécbu metastatického kolorektálního karcinomu.

BACKGROUND: The combination of modern systemic chemotherapy and anti-EGFR monoclonal antibodies improves overall survival and quality of life for patients with metastatic colorecal cancer. By contrast, the addition of anti-EGFR therapy to the treatment regime of resistant patients may lead to worse progression-free survival and overall survival. Therefore, identifying sensitive and resistant patients prior to targeted therapy of metastatic colorecal cancer is a key point during the initial decision making process. Previous research shows that primary resistance to EGFR blockade is in most cases caused by constitutive activation of signaling pathways downstream of EGFR. Of all relevant factors (mutation of KRAS, NRAS, BRAF, and PIK3CA oncogenes, inactivation of tumor suppressors PTEN and TP53, amplification of EGFR and HER2, and expression of epiregulin and amphiregulin, mikroRNA miR-31-3p, and miR-31-5p), only evaluation of KRAS and NRAS mutations has entered routine clinical practice. The role of the other markers still needs to be validated. The ongoing benefit of anti-EGFR therapy could be indicated by specific clinical parameters measured after the initiation of targeted therapy, including early tumor shrinkage, the deepness of the response, or hypomagnesemia. The accuracy of predictive dia-gnostic tools could be also increased by examining a combination of predictive markers using next generation sequencing methods. However, unjustified investigation of many molecular markers should be resisted as this may complicate interpretation of the results, particularly in terms of their specific clinical relevance. AIM: The aim of this review is to describe current possibilities with respect to predicting responses to EGFR blockade in the context of the EGFR pathway, and the utilization of such results in routine clinical practice.