A5008898554- Colorectal Cancer Surgical Treatments
- Colorectal and Anal Carcinomas
- Colorectal Cancer Screening and Detection
- Health Systems, Economic Evaluations, Quality of Life
- Radiomics and Machine Learning in Medical Imaging
- Advanced Radiotherapy Techniques
- Ethics in Clinical Research
- Gastric Cancer Management and Outcomes
- Stoma care and complications
- Anorectal Disease Treatments and Outcomes
- Meta-analysis and systematic reviews
- MRI in cancer diagnosis
- Radiation Dose and Imaging
- Palliative Care and End-of-Life Issues
- Economic and Financial Impacts of Cancer
- Healthcare cost, quality, practices
- Patient-Provider Communication in Healthcare
- Medical Imaging Techniques and Applications
- Anesthesia and Sedative Agents
- Childhood Cancer Survivors' Quality of Life
- Nausea and vomiting management
- Genetic factors in colorectal cancer
- Clinical practice guidelines implementation
- Frailty in Older Adults
- Diverticular Disease and Complications
University Medical Center Groningen
2018-2022
Medisch Centrum Leeuwarden
2019-2020
University Medical Center Utrecht
2014-2018
Utrecht University
2014-2018
Heidelberg University
2015-2018
University Hospital Heidelberg
2015-2018
Meander Medisch Centrum
2017
Although self-expandable metal stent (SEMS) placement as bridge to surgery (BTS) in patients with left-sided obstructing colonic cancer has shown promising short-term results, it is used infrequently owing uncertainty about its oncological safety. This population study compared long-term outcomes between emergency resection and SEMS BTS.Through a national collaborative research project, outcome data were collected for all who underwent 2009 2016 75 Dutch hospitals. Patients identified from...
Background: Systematic evaluation and validation of new prognostic predictive markers, technologies interventions for colorectal cancer (CRC) is crucial optimizing patients' outcomes. With only 5–15% patients participating in clinical trials, generalizability results poor. Moreover, current trials often lack the capacity post-hoc subgroup analyses. For this purpose, a large observational cohort study, serving as multiple trial biobanking facility, was set up by Dutch Colorectal Cancer Group...
IntroductionRectal cancer surgery with neoadjuvant therapy is associated substantial morbidity. The present study describes the course of quality life (QOL) in rectal patients first 2 years after start treatment.Patients and MethodsWe performed a prospective within colorectal cohort including who were referred for chemoradiation or short-course radiotherapy underwent surgery. QOL was assessed using European Organization Research Treatment Cancer core questionnaire (EORTC QLQ-C30) QLQ-CR29)...
Randomized controlled trials (RCTs)—the gold standard for evaluating the effects of medical interventions—are notoriously challenging in terms logistics, planning and costs. The cohort multiple randomized trial approach is designed to facilitate pragmatic evaluation (new) interventions a promising variation from conventional RCTs. In this paper, we evaluate methodological challenges conducting an RCT within cohort. We argue that equally valid results can be obtained conducted cohorts as...
PurposePathologic complete tumor response after chemoradiation in patients with locally advanced rectal cancer (LARC) is associated a favorable prognosis and allows organ-sparing treatment strategies. In the RECTAL-BOOST trial, we aimed to investigate effect of an external radiation boost before on pathologic or sustained clinical LARC.Methods MaterialsThis multicenter, nonblinded, phase 2 randomized controlled trial followed trials-within-cohorts design, which pragmatic design allowing...
The "cohort multiple randomized controlled trial," a new design for pragmatic trials, embeds trials within cohort. cohort RCT is an attractive alternative to conventional RCTs in fields where recruitment slow, (competing) interventions the same condition have be tested, are highly preferred by patients and doctors, risk of disappointment bias, cross-over, contamination considerable. To prevent these unwanted effects, provides information on randomization intervention group/arm only, only...
Reduction of motion uncertainty by applying adaptive radiotherapy strategies depends largely on the temporal behavior this motion. To fully optimize strategies, insight into target is needed. The purpose study was to analyze stability and evolution in time both gross tumor volume (GTV) clinical (CTV) for patients with rectal cancer. We scanned 16 daily during one week, a 1.5 T MRI scanner treatment position, prior each fraction. Single slice sagittal cine MRIs were made at beginning, middle,...
ObjectivesThe trials within cohorts (TwiCs) design aims to improve recruitment efficiency. We conducted the first TwiCs in radiation oncology and described efficiency of generalizability results.Study Design SettingIn two radiotherapy centers, patients with rectal cancer were asked participate a prospective cohort study provide broad consent for randomization patient-reported outcomes (PROs). Consenting who met trial criteria randomized directly after enrollment. The intervention arm was...
Background: Neoadjuvant chemoradiation with delayed surgery (CRT-DS) and short-course radiotherapy immediate (SCRT-IS) are two commonly used treatment strategies for rectal cancer. However, the optimal strategy patients intermediate-risk cancer remains a discussion. This study compares quality of life (QOL) between SCRT-IS CRT-DS from diagnosis until 24 months after treatment.Methods: In prospective colorectal cohort, clinical stage T2-3N0-2M0 undergoing or 2013 2017 were identified. QOL was...
Organ-sparing approaches, including wait-and-see and local excision, are increasingly being offered to patients with rectal cancer following a good response neoadjuvant therapy. Preferences regarding these treatment strategies yet unknown.This study aimed determine the preferences utility scores for approaches.This is cross-sectional study.This was conducted at Radiation-Oncology Department of University Medical Center Utrecht.Fifty-seven history 38 volunteers were included.Participants...
STopic 1: ContextA1 TwiCs RCTs can be explanatory, pragmatic or in-betweenMerrick Zwarenstein (merrick.zwarenstein@ices.on.ca)Schulich School of Medicine & Dentistry, Western University, London, Ontario, N6A 3K, CanadaRandomised controlled trials (RCTs) using the design streamline patient recruitment by tailoring and staging consent, allow for testing multiple interventions against a common control group, integrate evaluation into natural flow care. Are they pragmatic?Schwartz Lellouch [1]...
In patients diagnosed with rectal cancer, dose escalation is currently being investigated in a large number of studies. Since there little known on gross tumor volume (GTV) inter-fraction motion for wide variety margins used. Purpose this study to quantify GTV statistics different timescales and give estimates planning target (PTV) margins.Thirty-two patients, were included. To investigate from week-to-week, 16 underwent pretreatment five weekly MRIs, prior radiotherapy (RT) fraction the...
Abstract Purpose A substantial part (21–35%) of defunctioning stomas created during resection for colorectal cancer will never be reversed. Known risk factors non-closure are age, peri- or postoperative complications, comorbidity, and tumor stage. However, studies performed to identify these mostly focus on rectal include both preoperative factors. This study aims non-reversal intended temporary acute left-sided obstructive colon (LSOCC) with primary anastomosis. Methods All patients who...
Neoadjuvant short-course radiotherapy was routinely applied for nonlocally advanced rectal cancer (cT1-3N0-1M0 with >1 mm distance to the mesorectal fascia) in Netherlands following Dutch total excision trial. This policy has shifted toward selective application after guideline revision 2014.
To evaluate patients' experience of having served as controls without a notification at the time randomization in context trial within cohorts (TwiCs) design.Patients were asked for their opinion on TwiCs, before and after been provided results. Patients had broad consent to cohort entry one two TwiCs (an exercise program breast cancer treatment or radiotherapy dose-escalation rectal cancer).Two 6 years entry, 15% (n = 16) all patients remembered randomization. Before disclosure results, 47%...