Colorectal cancer (CRC) is a heterogeneous disease in which unique subtypes are characterized by distinct genetic and epigenetic alterations. Here we performed comprehensive genome-scale DNA ...methylation profiling of 125 colorectal tumors and 29 adjacent normal tissues. We identified four DNA methylation-based subgroups of CRC using model-based cluster analyses. Each subtype shows characteristic genetic and clinical features, indicating that they represent biologically distinct subgroups. A CIMP-high (CIMP-H) subgroup, which exhibits an exceptionally high frequency of cancer-specific DNA hypermethylation, is strongly associated with MLH1 DNA hypermethylation and the BRAF(V600E) mutation. A CIMP-low (CIMP-L) subgroup is enriched for KRAS mutations and characterized by DNA hypermethylation of a subset of CIMP-H-associated markers rather than a unique group of CpG islands. Non-CIMP tumors are separated into two distinct clusters. One non-CIMP subgroup is distinguished by a significantly higher frequency of TP53 mutations and frequent occurrence in the distal colon, while the tumors that belong to the fourth group exhibit a low frequency of both cancer-specific DNA hypermethylation and gene mutations and are significantly enriched for rectal tumors. Furthermore, we identified 112 genes that were down-regulated more than twofold in CIMP-H tumors together with promoter DNA hypermethylation. These represent ∼7% of genes that acquired promoter DNA methylation in CIMP-H tumors. Intriguingly, 48/112 genes were also transcriptionally down-regulated in non-CIMP subgroups, but this was not attributable to promoter DNA hypermethylation. Together, we identified four distinct DNA methylation subgroups of CRC and provided novel insight regarding the role of CIMP-specific DNA hypermethylation in gene silencing.
There is an increasing demand for accurate biomarkers for early non-invasive colorectal cancer detection. We employed a genome-scale marker discovery method to identify and verify candidate DNA ...methylation biomarkers for blood-based detection of colorectal cancer.
We used DNA methylation data from 711 colorectal tumors, 53 matched adjacent-normal colonic tissue samples, 286 healthy blood samples and 4,201 tumor samples of 15 different cancer types. DNA methylation data were generated by the Illumina Infinium HumanMethylation27 and the HumanMethylation450 platforms, which determine the methylation status of 27,578 and 482,421 CpG sites respectively. We first performed a multistep marker selection to identify candidate markers with high methylation across all colorectal tumors while harboring low methylation in healthy samples and other cancer types. We then used pre-therapeutic plasma and serum samples from 107 colorectal cancer patients and 98 controls without colorectal cancer, confirmed by colonoscopy, to verify candidate markers. We selected two markers for further evaluation: methylated THBD (THBD-M) and methylated C9orf50 (C9orf50-M). When tested on clinical plasma and serum samples these markers outperformed carcinoembryonic antigen (CEA) serum measurement and resulted in a high sensitive and specific test performance for early colorectal cancer detection.
Our systematic marker discovery and verification study for blood-based DNA methylation markers resulted in two novel colorectal cancer biomarkers, THBD-M and C9orf50-M. THBD-M in particular showed promising performance in clinical samples, justifying its further optimization and clinical testing.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background
A significant proportion of gallbladder polyps are non-neoplastic, for which resection is not necessary. However, international guidelines advocate cholecystectomy for all polyps ≥ 1 cm. ...This study assessed a national cohort of histopathologically proven gallbladder polyps to distinguish neoplastic from non-neoplastic polyps.
Methods
PALGA, the nationwide network and registry of histo- and cytopathology, was searched to identify all histopathologically proven gallbladder polyps between 2003 and 2013. All polyps and (focal) wall thickenings > 5 mm were included, and classified as neoplastic or non-neoplastic. Polyp subtype, size, distribution, presentation as wall thickening or protruding polyp, and presence of gallstones were assessed for neoplastic and non-neoplastic polyps. A decision tree to distinguish neoplastic and non-neoplastic polyps was made and diagnostic accuracy of 1 cm surgical threshold was calculated.
Results
A total of 2085 out of 220,612 cholecystectomies contained a polyp (0.9%). Of these polyps, 56.4% were neoplastic (40.1% premalignant, 59.9% malignant) and 43.6% non-neoplastic (41.5% cholesterol polyp, 37.0% adenomyomatosis, 21.5% other). Polyp size, distribution, and presence of gallstones were reported in 1059, 1739 and 1143 pathology reports, respectively. Neoplastic polyps differed from non-neoplastic polyps in size (18.1 mm vs 7.5 mm,
p
< 0.001), singularity (88.2% vs 68.2%,
p
< 0.001), wall thickening (29.1% vs 15.6%,
p
< 0.001), and presence of gallstones (50.1% vs 40.4%,
p
= 0.001). However, adenomyomatosis presented with similar characteristics as neoplastic polyps. Fifty percent of polyps were ≥ 1 cm surgical threshold (optimal surgical threshold based on ROC-curve); sensitivity for indicating neoplastic polyps was 68.1%, specificity was 70.2%, and positive and negative predictive values were 72.9% and 65.1%.
Conclusions
The prevalence of gallbladder polyps on cholecystectomy is low and many of the polyps are non-neoplastic. Clinicopathological characteristics differ between neoplastic and non-neoplastic polyps in general, but these cannot properly indicate neoplasia. The 1 cm surgical threshold has moderate diagnostic accuracy and is insufficient to indicate surgery for neoplastic gallbladder polyps.
Extensive changes in DNA methylation are common in cancer and may contribute to oncogenesis through transcriptional silencing of tumor-suppressor genes. Genome-scale studies have yielded important ...insights into these changes but have focused on CpG islands or gene promoters. We used whole-genome bisulfite sequencing (bisulfite-seq) to comprehensively profile a primary human colorectal tumor and adjacent normal colon tissue at single-basepair resolution. Regions of focal hypermethylation in the tumor were located primarily at CpG islands and were concentrated within regions of long-range (>100 kb) hypomethylation. These hypomethylated domains covered nearly half of the genome and coincided with late replication and attachment to the nuclear lamina in human cell lines. We confirmed the confluence of hypermethylation and hypomethylation within these domains in 25 diverse colorectal tumors and matched adjacent tissue. We propose that widespread DNA methylation changes in cancer are linked to silencing programs orchestrated by the three-dimensional organization of chromatin within the nucleus.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Background
Depression is associated with negative work outcomes such as reduced work participation (WP) (e.g., sick leave duration, work status) and work functioning (WF) (e.g., loss of productivity, ...work limitations). For the development of evidence-based interventions to improve these work outcomes, factors predicting WP and WF have to be identified.
Methods
This paper presents a systematic literature review of studies identifying factors associated with WP and WF of currently depressed workers.
Results
A total of 30 studies were found that addressed factors associated with WP (
N
= 19) or WF (
N
= 11). For both outcomes, studies reported most often on the relationship with disorder-related factors, whereas personal factors and work-related factors were less frequently addressed. For WP, the following relationships were supported: strong evidence was found for the association between a long duration of the depressive episode and work disability. Moderate evidence was found for the associations between more severe types of depressive disorder, presence of co-morbid mental or physical disorders, older age, a history of previous sick leave, and work disability. For WF, severe depressive symptoms were associated with work limitations, and clinical improvement was related to work productivity (moderate evidence). Due to the cross-sectional nature of about half of the studies, only few true prospective associations could be identified.
Conclusion
Our study identifies gaps in knowledge regarding factors predictive of WP and WF in depressed workers and can be used for the design of future research and evidence-based interventions. We recommend undertaking more longitudinal studies to identify modifiable factors predictive of WP and WF, especially work-related and personal factors.
Cholecystectomy is the preferred treatment for symptomatic cholecystolithiasis. However, persistent pain after cholecystectomy for symptomatic cholecystolithiasis is reported in up to 40% of ...patients. The aim of the SECURE trial is to compare the effectiveness of usual care with a restrictive strategy using a standardized work-up with stepwise selection for cholecystectomy in patients with gallstones and abdominal complaints. The SECURE trial is designed as a multicenter, randomized, parallel-arm, non-inferiority trial in patients with abdominal symptoms and ultrasound-proven gallstones or sludge. Randomization was performed to either usual care (standard practice, according to the physician's knowledge and experience, and physician's and patient's preference) or a restrictive standardized strategy: treated with interval evaluation and stepwise selection for laparoscopic cholecystectomy based on fulfilment of pre-specified criteria. This article presents in detail the statistical analysis plan (SAP) of this trial and was submitted before outcomes were available to the investigators.
The primary end point of this trial is defined as the proportion of patients being pain-free at 12 months' follow-up. Pain will be assessed with the Izbicki Pain Score. Secondary endpoints will be the proportion of patients with complications due to gallstones or cholecystectomy, quality of life, the association between the patients' symptoms and treatment, work performance, and cost-effectiveness.
The data from the SECURE trial will provide evidence whether or not a restrictive strategy in patients with symptomatic cholecystolithiasis is associated with similar patient reported outcomes and a reduction in the number of cholecystectomies compared to usual care. The data from this trial will be analyzed according to this pre-specified SAP.
The Netherlands National Trial Register NTR4022 . Registered on 5 June 2013.
OBJECTIVE:To perform a cost-effectiveness analysis (CEA) of restrictive strategy versus usual care in patients with gallstones and abdominal pain.
SUMMARY BACKGROUND DATA:A restrictive selection ...strategy for surgery in patients with gallstones reduces cholecystectomies, but the impact on overall costs and cost-effectiveness is unknown.
METHODS:Data of a multicentre, randomized-controlled trial (SECURE-trial) were used. Adult patients with gallstones and abdominal pain were included. Restrictive strategy was economically evaluated against usual care from a societal perspective. Hospital-use of resources was gathered with case-report forms and out-of-hospital consultations, out-of-pocket expenses, and productivity loss were collected with questionnaires. National unit costing was applied. The primary outcome was the cost per pain-free patient after 12 months.
RESULTS:All 1067 randomized patients (49.0 years, 73.7% females) were included. After 12 months, 56.2% of patients was pain-free in restrictive strategy versus 59.8% after usual care. The restrictive strategy significantly reduced the cholecystectomy rate with 7.7% and reduced surgical costs with 160 per patient, 162 was saved from a societal perspective. The cost-effectiveness plane showed that restrictive strategy was cost saving in 89.1%, but resulted in less pain-free patients in 88.5%. Overall, the restrictive strategy saved 4563 from a societal perspective per pain-free patient lost.
CONCLUSIONS:A restrictive selection strategy for cholecystectomy saves 162 compared to usual care, but results in fewer pain-free patients. The incremental cost per pain-free patient are savings of 4563 per pain-free patient lost. The higher societal willingness to pay for one extra pain-free patient, the lower the probability that the restrictive strategy will be cost-effective.
TRIAL REGISTRATION:The Netherlands National Trial Register NTR4022. Registered on 5 June 2013.
IMPORTANCE: There is currently no consensus on the indication for cholecystectomy in patients with uncomplicated gallstone disease. OBJECTIVE: To report on the development and validation of a ...multivariable prediction model to better select patients for surgery. DESIGN, SETTING, AND PARTICIPANTS: This study evaluates data from 2 multicenter prospective trials (the previously published Scrutinizing (In)efficient Use of Cholecystectomy: A Randomized Trial Concerning Variation in Practice SECURE and the Standardized Work-up for Symptomatic Cholecystolithiasis Success trial) collected from the outpatient clinics of 25 Dutch hospitals between April 2014 and June 2019 and including 1561 patients with symptomatic uncomplicated cholelithiasis, defined as gallstone disease without signs of complicated cholelithiasis (ie, biliary pancreatitis, cholangitis, common bile duct stones or cholecystitis). Data were analyzed from January 2020 to June 2020. EXPOSURES: Patient characteristics, comorbidity, surgical outcomes, pain, and symptoms measured at baseline and at 6 months’ follow-up. MAIN OUTCOMES AND MEASURES: A multivariable regression model to predict a pain-free state or a clinically relevant reduction in pain after surgery. Model performance was evaluated using calibration and discrimination. RESULTS: A total of 1561 patients were included (494 patients in 7 hospitals in the development cohort and 1067 patients in 24 hospitals in the validation cohort; 6 hospitals included patients in both cohorts). In the development cohort, 395 patients (80.0%) underwent cholecystectomy. After surgery, 225 patients (57.0%) reported that they were pain free and 295 (74.7%) reported a clinically relevant reduction in pain. A multivariable prediction model showed that increased age, no history of abdominal surgery, increased visual analog scale pain score at baseline, pain radiation to the back, pain reduction with simple analgesics, nausea, and no heartburn were independent predictors of clinically relevant pain reduction after cholecystectomy. After internal validation, good discrimination was found (C statistic, 0.80; 95% CI, 0.74-0.84) between patients with and without clinically relevant pain reduction. The model had very good overall calibration and minimal underestimation of the probability. External validation indicated a good discrimination between patients with and without clinically relevant pain reduction (C statistic, 0.74; 95% CI, 0.70-0.78) and fair calibration with some overestimation of probability by the model. CONCLUSIONS AND RELEVANCE: The model validated in this study may help predict the probability of pain reduction after cholecystectomy and thus aid surgeons in deciding whether patients with uncomplicated cholelithiasis will benefit from cholecystectomy.
Aggressive melanoma cells are able to form alternative routes for angiogenesis. The formation of extracellular matrix-rich vasculogenic-like networks periodic acid Schiff (PAS) loops and expression ...of endothelial-associated genes allowing direct contact of erythrocytes (blood lakes) are forms of vasculogenic mimicry (VM). The detection of these alternative routes may be used as an additional staging factor for cutaneous melanoma and predicts the route of metastasis in melanoma. We studied the association of the presence of VM with metastasis (lymphogenous and/or haematogenous) in patients diagnosed with cutaneous malignant melanoma in het Groene Hart Hospital, the Netherlands, between 1995 and 2000. Tumour tissue samples of 123 patients were assessed on PAS loops and blood lakes and correlated to clinical data. VM was detected in 42 (34%) and proven metastasis developed in 23 patients (18.7%). VM was associated with shorter survival (P<0.001). In 36 tumours, PAS loops were detected. PAS loops were correlated with the presence of lymphogenous as well as haematogenous metastasis (P=0.062 and 0.013). In 20 tumours, blood lakes were detected and correlated with haematogenous metastasis (P<0.001). In multivariate analyses, the detected blood lakes were significantly associated with haematogenous metastasis (P<0.001, adjusted odds ratio 6.8, 95% confidence interval 1.47-31). Blood lakes were strongly correlated with haematogenous metastasis of cutaneous melanoma and were an independent determinant for survival. These interesting findings need further investigation, although we believe that implementation of this detection can directly lead to better staging of cutaneous melanoma.
•Implementation of the restrictive strategy results in savings of €5.4-15.6 million•This is comparable with 1.7%-5.6% of the total budget•Considering a patient's sex and BMI, for the decision of ...surgery seems beneficial.
A cost-effectiveness analysis of a multicenter randomized-controlled trial comparing restrictive strategy versus usual care in patients with gallstones showed that savings by restrictive strategy could not compensate for the lower proportion of pain-free patients. However, four subgroups based on combined stratification factors resulted in less cholecystectomies and more pain-free patients in restrictive strategy (female-low volume-BMI > 30, female-low volume-BMI25-30, female-high volume-BMI25-30, and male-low volume-BMI < 25). The aim of this study was to explore the budget impact from a hospital healthcare perspective of implementation of restrictive strategy in these subgroups.
Data of the SECURE-trial were used to calculate the hospital budget impact with a time horizon of four years. Based on a study into practice variation, about 19% of hospitals treat patients according restrictive strategy. This represents the proportion of patients treated according restrictive strategy at the start of budget period. Three subanalyses were performed: a scenario analysis in which 30% of patients fall under a restrictive strategy in clinical practice, a sensitivity analysis in which we calculated the budget impact with the low and high 95% confidence limits of the expected future number of patients, a subgroup analysis in which restrictive strategy was also implemented in two additional subgroups (male-high volume-BMI < 25 and female-high volume-BMI >30).
Budget impact analysis showed savings of €6.7-€15.6 million (2.2%-5.6%) for the period 2021-2024/2025 by implementing the restrictive strategy in the four subgroups and provision of usual care in other patients. Sensitivity analysis with 30% of patients already in the restrictive strategy at the start of the budget period, resulted in savings between €5.4 million and €14.0 million (1.7%-5.0%).
Performing a restrictive strategy for selection of cholecystectomy in subgroups of patients and provision of usual care in other patients will result in a lower overall hospital budget needed to treat patients with abdominal pain and gallstones.
The Netherlands National Trial Register NTR4022. Registered on June 5, 2013.
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