85 research outputs found

    Hepatic vessel segmentation using a reduced filter 3D U-Net in ultrasound imaging

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    Accurate hepatic vessel segmentation on ultrasound (US) images can be an important tool in the planning and execution of surgery, however proves to be a challenging task due to noise and speckle. Our method comprises a reduced filter 3D U-Net implementation to automatically detect hepatic vasculature in 3D US volumes. A comparison is made between volumes acquired with a 3D probe and stacked 2D US images based on electromagnetic tracking. Experiments are conducted on 67 scans, where 45 are used in training, 12 in validation and 10 in testing. This network architecture yields Dice scores of 0.740 and 0.781 for 3D and stacked 2D volumes respectively, comparing promising to literature and inter-observer performance (Dice = 0.879).Comment: 3 pages, conference extended abstract. MIDL 2019 [arXiv:1907.08612

    Hand-assisted retroperitoneoscopic versus standard laparoscopic donor nephrectomy: HARP-trial

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    Contains fulltext : 88436.pdf (publisher's version ) (Open Access)BACKGROUND: Transplantation is the only treatment offering long-term benefit to patients with chronic kidney failure. Live donor nephrectomy is performed on healthy individuals who do not receive direct therapeutic benefit of the procedure themselves. In order to guarantee the donor's safety, it is important to optimise the surgical approach. Recently we demonstrated the benefit of laparoscopic nephrectomy experienced by the donor. However, this method is characterised by higher in hospital costs, longer operating times and it requires a well-trained surgeon. The hand-assisted retroperitoneoscopic technique may be an alternative to a complete laparoscopic, transperitoneal approach. The peritoneum remains intact and the risk of visceral injuries is reduced. Hand-assistance results in a faster procedure and a significantly reduced operating time. The feasibility of this method has been demonstrated recently, but as to date there are no data available advocating the use of one technique above the other. METHODS/DESIGN: The HARP-trial is a multi-centre randomised controlled, single-blind trial. The study compares the hand-assisted retroperitoneoscopic approach with standard laparoscopic donor nephrectomy. The objective is to determine the best approach for live donor nephrectomy to optimise donor's safety and comfort while reducing donation related costs. DISCUSSION: This study will contribute to the evidence on any benefits of hand-assisted retroperitoneoscopic versus standard laparoscopic donor nephrectomy. TRIAL REGISTRATION: Dutch Trial Register NTR1433

    Extracellular Granzyme K Modulates Angiogenesis by Regulating Soluble VEGFR1 Release From Endothelial Cells

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    Angiogenesis is crucial for normal development and homeostasis, but also plays a role in many diseases including cardiovascular diseases, autoimmune diseases, and cancer. Granzymes are serine proteases stored in the granules of cytotoxic cells, and have predominantly been studied for their pro-apoptotic role upon delivery in target cells. A growing body of evidence is emerging that granzymes also display extracellular functions, which largely remain unknown. In the present study, we show that extracellular granzyme K (GrK) inhibits angiogenesis and triggers endothelial cells to release soluble VEGFR1 (sVEGFR1), a decoy receptor that inhibits angiogenesis by sequestering VEGF-A. GrK does not cleave off membrane-bound VEGFR1 from the cell surface, does not release potential sVEGFR1 storage pools from endothelial cells, and does not trigger sVEGFR1 release via protease activating receptor-1 (PAR-1) activation. GrK induces de novo sVEGFR1 mRNA and protein expression and subsequent release of sVEGFR1 from endothelial cells. GrK protein is detectable in human colorectal tumor tissue and its levels positively correlate with sVEGFR1 protein levels and negatively correlate with T4 intratumoral angiogenesis and tumor size. In conclusion, extracellular GrK can inhibit angiogenesis via secretion of sVEGFR1 from endothelial cells, thereby sequestering VEGF-A and impairing VEGFR signaling. Our observation that GrK positively correlates with sVEGFR1 and negatively correlates with angiogenesis in colorectal cancer, suggest that the GrK-sVEGFR1-angiogenesis axis may be a valid target for development of novel anti-angiogenic therapies in cancer

    Short-term postoperative outcomes after liver resection in the elderly patient:a nationwide population-based study

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    BACKGROUND: Liver resection is high-risk surgery in particular in elderly patients. The aim of this study was to explore postoperative outcomes after liver resection in elderly patients. METHODS: In this nationwide study, all patients who underwent liver resection for primary and secondary liver tumours in the Netherlands between 2014 and 2019 were included. Age groups were composed as younger than 70 (70-), between 70 and 80 (septuagenarians), and 80 years or older (octogenarians). Proportion of liver resections per age group and 30-day major morbidity and 30-day mortality were assessed. RESULTS: In total, 6587 patients were included of whom 4023 (58.9%) were younger than 70, 2135 (32.4%) were septuagenarians and 429 (6.5%) were octogenarians. The proportion of septuagenarians increased during the study period (aOR:1.06, CI:1.02-1.09, p < 0.001). Thirty-day major morbidity was higher in septuagenarians (11%) and octogenarians (12%) compared to younger patients (9%, p = 0.049). Thirty-day mortality was higher in septuagenarians (4%) and octogenarians (4%) compared to younger patients (2%, p < 0.001). Cardiopulmonary complications occurred more frequently with higher age, liver-specific complications did not. Higher age was associated with higher 30-day morbidity and 30-day mortality in multivariable logistic regression. CONCLUSION: Thirty-day major morbidity and 30-day mortality are higher after liver resection in elderly patients, attributed mainly to non-surgical cardiopulmonary complications

    Hospital variation and outcomes of simultaneous resection of primary colorectal tumour and liver metastases:a population-based study

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    BACKGROUND: The optimal treatment sequence for patients with synchronous colorectal liver metastases (CRLM) remains uncertain. This study aimed to assess factors associated with the use of simultaneous resections and impact on hospital variation. METHOD: This population-based study included all patients who underwent liver surgery for synchronous colorectal liver metastases between 2014 and 2019 in the Netherlands. Factors associated with simultaneous resection were identified. Short-term surgical outcomes of simultaneous resections and factors associated with 30-day major morbidity were evaluated. RESULTS: Of 2146 patients included, 589 (27%) underwent simultaneous resection in 28 hospitals. Simultaneous resection was associated with age, sex, BMI, number, size and bilobar distribution of CRLM, and administration of preoperative chemotherapy. More minimally invasive and minor resections were performed in the simultaneous group. Hospital variation was present (range 2.4%-83.3%) with several hospitals performing simultaneous procedures more and less frequently than expected. Simultaneous resection resulted in 13% 30-day major morbidity, and 1% mortality. ASA classification ≥3 was independently associated with higher 30-day major morbidity after simultaneous resection (aOR 1.97, CI 1.10-3.42, p = 0.018). CONCLUSION: Distinctive patient and tumour characteristics influence the choice for simultaneous resection. Remarkable hospital variation is present in the Netherlands

    Population-based study on practice variation regarding preoperative systemic chemotherapy in patients with colorectal liver metastases and impact on short-term outcomes

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    Introduction: Definitions regarding resectability and hence indications for preoperative chemotherapy vary. Use of preoperative chemotherapy may influence postoperative outcomes. This study aimed to assess the variation in use of preoperative chemotherapy for CRLM and related postoperative outcomes in the Netherlands. Materials and methods: All patients who underwent liver resection for CRLM in the Netherlands between 2014 and 2018 were included from a national database. Case-mix factors contributing to the use of preoperative chemotherapy, hospital variation and postoperative outcomes were assessed using multivariable logistic regression. Postoperative outcomes were postoperative complicated course (PCC), 30-day morbidity and 30-day mortality. Results: In total, 4469 patients were included of whom 1314 patients received preoperative chemotherapy and 3155 patients did not. Patients receiving chemotherapy were significantly younger (mean age (+SD) 66.3 (10.4) versus 63.2 (10.2) p < 0.001) and had less comorbidity (Charlson scores 2+ (24% versus 29%, p = 0.010). Unadjusted hospital variation concerning administration of preoperative chemotherapy ranged between 2% and 55%. After adjusting for case-mix factors, three hospitals administered significantly more preoperative chemotherapy than expected and six administered significantly less preoperative chemotherapy than expected. PCC was 12.1%, 30-day morbidity was 8.8% and 30-day mortality was 1.5%. No association between preoperative chemotherapy and PCC (OR 1.24, 0.98–1.55, p = 0.065), 30-day morbidity (OR 1.05, 0.81–1.39, p = 0.703) or with 30-day mortality (OR 1.22, 0.75–2.09, p = 0.467) was found. Conclusion: Significant hospital variation in the use of preoperative chemotherapy for CRLM was present in the Netherlands. No association between postoperative outcomes and use of preoperative chemotherapy was found

    Factors associated with failure to rescue after liver resection and impact on hospital variation:a nationwide population-based study

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    BACKGROUND: Failure to rescue (FTR) is defined as postoperative complications leading to mortality. This nationwide study aimed to assess factors associated with FTR and hospital variation in FTR after liver surgery. METHODS: All patients who underwent liver resection between 2014 and 2017 in the Netherlands were included. FTR was defined as in-hospital or 30-day mortality after complications Dindo grade ≥3a. Variables associated with FTR and nationwide hospital variation were assessed using multivariable logistic regression. RESULTS: Of 4961 patients included, 3707 (74.4%) underwent liver resection for colorectal liver metastases, 379 (7.6%) for other metastases, 526 (10.6%) for hepatocellular carcinoma and 349 (7.0%) for biliary cancer. Thirty-day major morbidity was 11.5%. Overall mortality was 2.3%. FTR was 19.1%. Age 65-80 (aOR: 2.86, CI:1.01-12.0, p = 0.049), ASA 3+ (aOR:2.59, CI: 1.66-4.02, p < 0.001), liver cirrhosis (aOR:4.15, CI:1.81-9.22, p < 0.001), biliary cancer (aOR:3.47, CI: 1.73-6.96, p < 0.001), and major resection (aOR:6.46, CI: 3.91-10.9, p < 0.001) were associated with FTR. Postoperative liver failure (aOR: 26.9, CI: 14.6-51.2, p < 0.001), cardiac (aOR: 2.62, CI: 1.27-5.29, p = 0.008) and thromboembolic complications (aOR: 2.49, CI: 1.16-5.22, p = 0.017) were associated with FTR. After case-mix correction, no hospital variation in FTR was observed. CONCLUSION: FTR is influenced by patient demographics, disease and procedural burden. Prevention of postoperative liver failure, cardiac and thromboembolic complications could decrease FTR

    Identification of genes for normalization of real-time RT-PCR data in breast carcinomas

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    <p>Abstract</p> <p>Background</p> <p>Quantitative real-time RT-PCR (RT-qPCR) has become a valuable molecular technique in basic and translational biomedical research, and is emerging as an equally valuable clinical tool. Correlation of inter-sample values requires data normalization, which can be accomplished by various means, the most common of which is normalization to internal, stably expressed, reference genes. Recently, such traditionally utilized reference genes as GAPDH and B2M have been found to be regulated in various circumstances in different tissues, emphasizing the need to identify genes independent of factors influencing the tissue, and that are stably expressed within the experimental milieu. In this study, we identified genes for normalization of RT-qPCR data for invasive breast cancer (IBC), with special emphasis on estrogen receptor positive (ER+) IBC, but also examined their applicability to ER- IBC, normal breast tissue and breast cancer cell lines.</p> <p>Methods</p> <p>The reference genes investigated by qRT-PCR were RPLP0, TBP, PUM1, ACTB, GUS-B, ABL1, GAPDH and B2M. Biopsies of 18 surgically-excised tissue specimens (11 ER+ IBCs, 4 ER- IBCs, 3 normal breast tissues) and 3 ER+ cell lines were examined and the data analyzed by descriptive statistics, geNorm and NormFinder. In addition, the expression of selected reference genes in laser capture microdissected ER+ IBC cells were compared with that of whole-tissue.</p> <p>Results</p> <p>A group of 3 genes, TBP, RPLP0 and PUM1, were identified for both the combined group of human tissue samples (ER+ and ER- IBC and normal breast tissue) and for the invasive cancer samples (ER+ and ER- IBC) by GeNorm, where NormFinder consistently identified PUM1 at the single best gene for all sample combinations.</p> <p>Conclusion</p> <p>The reference genes of choice when performing RT-qPCR on normal and malignant breast specimens should be either the collected group of 3 genes (TBP, RPLP0 and PUM1) employed as an average, or PUM1 as a single gene.</p

    Case-mix adjustment to compare nationwide hospital performances after resection of colorectal liver metastases

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    Background: Differences in patient demographics and disease burden can influence comparison of hospital performances. This study aimed to provide a case-mix model to compare short-term postoperative outcomes for patients undergoing liver resection for colorectal liver metastases (CRLM). Methods: This retrospective, population-based study included all patients who underwent liver resection for CRLM between 2014 and 2018 in the Netherlands. Variation in case-mix variables between hospitals and influence on postoperative outcomes was assessed using multivariable logistic regression. Primary outcomes were 30-day major morbidity and 30-day mortality. Validation of results was performed on the data from 2019. Results: In total, 4639 patients were included in 28 hospitals. Major morbidity was 6.2% and mortality was 1.4%. Uncorrected major morbidity ranged from 3.3% to 13.7% and mortality ranged from 0.0% to 5.0%. between hospitals. Significant differences between hospitals were observed for age higher than 80 (0.0%-17.1%, p <0.001), ASA 3 or higher (3.3%-36.3%, p <0.001), histopathological parenchymal liver disease (0.0%-47.1%, p <0.001), history of liver resection (8.1%-36.3%, p <0.001), major liver resection (6.7%-38.0%, p <0.001) and synchronous metastases (35.5%-62.1%, p <0.001). Expected 30-day major morbidity between hospitals ranged from 6.4% to 11.9% and expected 30-day mortality ranged from 0.6% to 2.9%. After case-mix correction no significant outliers concerning major morbidity and mortality remained. Validation on patients who underwent liver resection for CRLM in 2019 affirmed these outcomes. Conclusion: Case-mix adjustment is a prerequisite to allow for institutional comparison of short-term postoperative outcomes after liver resection for CRLM. (C) 2020 University Medical Center Groningen. Published by Elsevier Ltd
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