Differences in treatment of stage I colorectal cancers:A population-based study of colorectal cancers detected within and outside of a screening program

Background:Screen-detected colorectal cancers (CRCs) are often treated less invasively than stage-matched nonscreen-detected CRCs, but the reasons for this are not fully understood. This study evaluated the treatment of stage I CRCs detected within and outside of the screening program in the Netherlands. Methods:Data from the Netherlands Cancer Registry for all stage I CRCs diagnosed between January 1, 2008 and December 31, 2020 were analyzed, comparing patient, tumor, and treatment characteristics of screen-detected and nonscreen-detected stage I CRCs. Multivariable logistic regression was used to assess the association between treatment (local excision only vs. surgical oncologic resection) and patient and tumor characteristics, stratified for T stage and tumor location. Results:Screen-detected stage I CRCs were relatively more often T1 than T2 compared with non-screen-detected stage I CRCs (66.9 % vs. 53.3 %; P 0.001). When only T1 tumors were considered, both screen-detected colon and rectal cancers were more often treated with local excision only than non-screen-detected T1 cancers (odds ratio [OR] 2.19, 95%CI 1.93 2.49; and OR 1.29, 95 %CI 1.05 1.59, respectively), adjusted for sex, tumor location, lymphovascular invasion (LVI) status, and tumor differentiation. Conclusions:Less invasive treatment of screen-detected stage I CRC is partly explained by the higher rate of T1 cancers compared with non-screen-detected stage I CRCs. T1 stage I screen-detected CRCs were also more likely to undergo less invasive treatment than non-screen-detected CRCs, adjusted for risk factors such as LVI and tumor differentiation. Future research should investigate whether the choice of local excision was related to unidentified cancerrelated factors or the expertise of the endoscopists.</p

Colorectal Cancer Stage Distribution at First and Repeat Fecal Immunochemical Test Screening

Background &amp; Aims: For colorectal cancer (CRC) screening to be effective, it is important that screen-detected cancers are found at an early stage. Studies on stage distribution of screen-detected CRC at repeat screening of large population-based fecal immunochemical test (FIT)-based screening programs and the impact of FIT cut-off values on staging currently are lacking. Methods: We obtained data for FIT-positive participants (FIT cut-off, 47 μg hemoglobin/g feces) at their first or second (ie, repeat) screening from the Dutch National Screening Database from 2014 to 2018. Tumor characteristics were acquired through linkage with The Netherlands Cancer Registry. We compared stage at diagnosis (I–II vs III–IV) of CRCs detected at a first or second screening. In addition, we analyzed the hypothetical yield and stage distribution of CRC for different FIT cut-off values up to 250 μg hemoglobin/g feces.Results: At the first and second screenings, respectively, 15,755 and 3304 CRCs were detected. CRCs detected at the first or second screening were equally likely to be stages I to II (66.5% vs 67.7%; relative risk, 1.02; 95% CI, 1.00–1.05). A hypothetical increase of the FIT cut-off value from 47 μg to 250 μg resulted in a reduction of detected CRCs by 88.3% and 79.0% at the first or second screening, respectively. Even then, the majority of detected CRCs (63%–64%) still would be diagnosed at stages I to II. Conclusions: FIT-based screening is effective in downstaging CRC, and also at repeat screening. Increasingly, the FIT cut-off level has a limited impact on the stage distribution of detected CRCs, although it greatly affects CRC detection and thus is important to keep low.</p

Application profiling and resource management for MapReduce

Scale of data generated and processed is exponential growth in the Big Data ear. It poses a challenge that is far beyond the goal of a single computing system. Processing such vast amount of data on a single machine is impracticable in term of time or cost. Hence, distributed systems, which can harness very large clusters of commodity computers and processing data within restrictive time deadlines, are imperative. In this thesis, we target two aspects of distributed systems: application profiling and resource management. We study a MapReduce system in detail, which is a programming paradigm for large scale distributed computing, and presents solutions to tackle three key problems. Firstly, this thesis analyzes the characteristics of jobs running on the MapReduce system to reveal the problem—the Application scope of MapReduce has been extended beyond the original design goal that was large-scale data processing. This problem enables us to present a Workload Characteristic Oriented Scheduler (WCO), which strives for co-locating tasks of possibly different MapReduce jobs with complementing resource usage characteristics. Secondly, this thesis studies the current job priority mechanism focusing on resource management. In the MapReduce system, job priority only exists at scheduling level. High priority jobs are placed at the front of the scheduling queue and dispatched first. Resource, however, is fairly shared among jobs running at the same worker node without any consideration for their priorities. In order to resolve this, this thesis presents a non-intrusive slot layering solution, which dynamically allocates resource between running jobs based on their priority and efficiently reduces the execution time of high priority jobs while improves overall throughput. Last, based on the fact of underutilization of resource at each individual worker node, this thesis propose a new way, Local Resource Shaper (LRS), to smooth resource consumption of each individual job by automatically tuning the execution of concurrent jobs to maximize resource utilization while minimizing resource contention

Networks of inter-organisational coordination during disease outbreaks

Multi-organisational environment is demonstrating more complexities due the ever-increasing tasks’ complications in modern environments. Disease outbreak coordination is one of these complex tasks that require multi-skilled and multi-jurisdictional agencies to coordinate in dynamic environment. This research discusses theoretical foundations and practical approaches to suggest frameworks to study complex inter-organisational networks in dynamic environments, specifically during disease outbreak. We study coo¬¬rdination as being an interdisciplinary domain, and then uses social network theory to model it. I have surveyed 70 health professionals whom have participated in the swine influenza H1N1 2009 outbreak. I collected both qualitative and quantitative data in order to build a comprehensive understanding of the dynamics of the inter-organisational network that evolved during that outbreak. Then I constructed a performance model by use three main components of the network theory: degree centrality, connectedness and tie strength as the independent variables, and disease outbreak inter-organisational performance as the dependent one. In addition, we study both the formal networks and the informal ones. Formal networks are based on the standard operating structures, and the informal ones emerge based on trust, mutual benefits and relationships. Results suggest that the proposed social network measures have positive effect on coordination performance during the outbreak in both formal and informal networks, except centrality in the formal one. In addition, none of those measures influence performance before the outbreak. Practically, the results suggest that increasing the communication frequency and diversifying the tiers of the inter-organisational links enhance the overall network’s performance in formal coordination. In the informal one, links are created with the intention to improve performance; hence, all suggested network measures improve performance

The Importance of the Pathologist’s Role in Assessment of the Quality of the Mesorectum

Total mesorectal excision (TME) is considered standard of care for rectal cancer treatment. Failure to remove the mesorectal fat envelope entirely may explain part of observed local and distant recurrences. Several studies suggest quality of the mesorectum after TME surgery as determined by pathological evaluation may influence prognosis. We aimed to determine the prognostic value of the plane of surgery as well as factors influencing the likelihood of a high-quality specimen by reviewing the literature. A pooled meta-analysis of relevant outcome data was performed where appropriate. A muscularis propria resection plane was found to increase the risk of local recurrence (RR 2.72 [95 % CI 1.36 to 5.44]) and overall recurrence (RR 2.00 [95 % CI 1.17 to 3.42]) compared to an (intra)mesorectal plane. Plane of surgery is an important factor in rectal cancer treatment and the documentation by pathologists is essential for the improvement of TME quality and patient outcome

Liver Resection for Hepatic Metastases from Soft Tissue Sarcoma:A Nationwide Study

Contains fulltext : 209467pub.pdf (publisher's version ) (Open Access

Endoscopic and surgical treatment outcomes of colitis-associated advanced colorectal neoplasia:a multicenter cohort study

BACKGROUND: Inflammatory bowel disease (IBD) patients are at increased risk of advanced neoplasia (high-grade dysplasia or colorectal cancer). The authors aimed to (1) assess synchronous and metachronous neoplasia following (sub)total or proctocolectomy, partial colectomy or endoscopic resection for advanced neoplasia in IBD, and (2) identify factors associated with treatment choice.MATERIAL AND METHODS: In this retrospective multicenter cohort study, the authors used the Dutch nationwide pathology databank (PALGA) to identify patients diagnosed with IBD and colonic advanced neoplasia (AN) between 1991 and 2020 in seven hospitals in the Netherlands. Logistic and Fine &amp; Gray's subdistribution hazard models were used to assess adjusted subdistribution hazard ratios for metachronous neoplasia and associations with treatment choice.RESULTS: The authors included 189 patients (high-grade dysplasia n =81; colorectal cancer n =108). Patients were treated with proctocolectomy ( n =33), (sub)total colectomy ( n =45), partial colectomy ( n =56) and endoscopic resection ( n =38). Partial colectomy was more frequently performed in patients with limited disease and older age, with similar patient characteristics between Crohn's disease and ulcerative colitis. Synchronous neoplasia was found in 43 patients (25.0%; (sub)total or proctocolectomy n =22, partial colectomy n =8, endoscopic resection n =13). The authors found a metachronous neoplasia rate of 6.1, 11.5 and 13.7 per 100 patient-years after (sub)total colectomy, partial colectomy and endoscopic resection, respectively. Endoscopic resection, but not partial colectomy, was associated with an increased metachronous neoplasia risk (adjusted subdistribution hazard ratios 4.16, 95% CI 1.64-10.54, P &lt;0.01) compared with (sub)total colectomy.CONCLUSION: After confounder adjustment, partial colectomy yielded a similar metachronous neoplasia risk compared to (sub)total colectomy. High metachronous neoplasia rates after endoscopic resection underline the importance of strict subsequent endoscopic surveillance.</p

The second round of the Dutch colorectal cancer screening program: Impact of an increased fecal immunochemical test cut-off level on yield of screening

The Dutch colorectal cancer (CRC) screening program started in 2014, inviting the target population biennially to perform a fecal immunochemical test (FIT). We obtained prospectively collected data from the national screening information-system to present the results of the second round (2016) and evaluate the impact of increasing the FIT cut-off halfway through the first round from 15 to 47 μg Hb/g feces on outcomes in the second round. Second round screening was done with a 47 μg Hb/g feces FIT cut-off. Participants were classified based on first round participation status as either FIT (15,47) or FIT (47,47) participants, and previous nonparticipants. In total, 348,891 (75.9%) out of 459,740 invitees participated in the second round. Participation rates were 93.4% among previous participants and 21.0% among previous non-participants. FIT(47,47) participants had a significantly higher detection rate of AN (15.3 vs. 10.4 per 1,000 participants) compared to FIT(15,47) participants in the second round, while their cumulative detection rate of AN over two rounds was significantly lower (45.6 vs. 52.6 per 1,000 participants). Our results showed that participation in the Dutch CRC screening program was consistently high and that second round detection rates depended on the first round FIT cut-off. The cumulative detection over two rounds was higher among FIT(15,47) participants. These findings suggest that a substantial part of, but not all the missed findings in the first round due to the increased FIT cut-off were detected in the subsequent round

Tumor deposits in colorectal cancer: improving the value of modern staging - a systematic review and meta-analysis

PURPOSE: Colorectal cancer (CRC) treatment is largely determined by tumor stage. Despite improvements made in the treatment of various types of metastatic disease, staging has not been refined. The role of tumor deposits (TD) in staging remains under debate. We have assessed the relation of TD with metastatic pattern, to evaluate whether TD might add significant new information to staging. METHODS: We performed a systematic literature search focused on the role of TD in CRC. Studies with neoadjuvant treated patients were excluded. Data on stage, histological factors and outcome were extracted. Data from four large cohorts were analyzed for the relevance of the presence of TD, lymph node metastases (LNM) and extramural vascular invasion (EMVI) on the pattern of metastases and outcomes. RESULTS: Of the 10,106 included CRC patients 22% presented with TD. TD are invariably associated with poor outcome. The presence of TD was associated with the presence of LNM and EMVI. In a pair wise comparison, the effects of TD were stronger than both LNM and EMVI. In the logistic regression model, TD in combination with LNM is the strongest predictor for liver (odds ratio (OR) 5.5), lung (OR 4.3) and peritoneal metastases (OR 7.0). The presence of EMVI adds information for liver and lung metastases, but not for peritoneal metastases. CONCLUSION: We have shown that TD are not equal to LNM or EMVI, with respect to biology and outcome. We lose valuable prognostic information by allocating TD into nodal category N1c and only considering TD in the absence of LNM. Therefore, we propose that the number of TD should be added to the number of LNM to derive a final N stage