Joost M. Klaase

Dr. Joost M. Klaase


Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 January 2021 in Annals of Surgery
Verified
Journal Article
Open access
ABAnnefleur E. M. Berkel
Annefleur E. M. Berkel
BBBart C. Bongers
Bart C. Bongers
HKHayke Kotte
Hayke Kotte
PWPaul Weltevreden
Paul Weltevreden
FJFrans H. C. de Jongh
Frans H. C. de Jongh
JKJoost M. Klaase
Joost M. Klaase
Objective: To assess the effects of a 3-week community-based exercise program on 30-day postoperative complications in high-risk patients scheduled for elective colorectal resection for (pre)malignancy. Summary Background Data: Patients with a low preoperative aerobic fitness undergoing colorectal surgery have an increased risk of postoperative complications. It remains, however, to be demonstrated whether prehabilitation in these patients reduces postoperative complications. Methods: This 2-center, prospective, single-blinded randomized clinical trial was carried out in 2 large teaching hospitals in the Netherlands. Patients (≥60 years) with colorectal (pre)malignancy scheduled for elective colorectal resection and with a score ≤7 metabolic equivalents on the veterans-specific activity questionnaire were randomly assigned to the prehabilitation group or the usual care group by using block-stratified randomization. An oxygen uptake at the ventilatory anaerobic threshold <11 mL/kg/min at the baseline cardiopulmonary exercise test was the final inclusion criterion. Inclusion was based on a power analysis. Patients in the prehabilitation group participated in a personalized 3-week (3 sessions per week, nine sessions in total) supervised exercise program given in community physical therapy practices before colorectal resection. Patients in the reference group received usual care. The primary outcome was the number of patients with one or more complications within 30 days of surgery, graded according to the Clavien-Dindo classification. Data were analyzed on an intention-to-treat basis. Results: Between February 2014 and December 2018, 57 patients [30 males and 27 females; mean age 73.6 years (standard deviation 6.1), range 61–88 years] were randomized to either prehabilitation (n = 28) or usual care (n = 29). The rate of postoperative complications was lower in the prehabilitation group (n = 12, 42.9%) than in the usual care group (n = 21, 72.4%, relative risk 0.59, 95% confidence interval 0.37–0.96, P = 0.024). Conclusions: Exercise prehabilitation reduced postoperative complications in high-risk patients scheduled to undergo elective colon resection for (pre)malignancy. Prehabilitation should be considered as usual care in high-risk patients scheduled for elective colon, and probably also rectal, surgery.

9 March 2016 in Trials
Verified
Journal Article
Open access
PDF file
F(for the Dutch Pancreatic Cancer Group (DPCG)
for the Dutch Pancreatic Cancer Group (DPCG)
EVEva Versteijne
Eva Versteijne
Casper Van EijckCasper Van Eijck
Casper Van Eijck
CPCornelis J. A. Punt
Cornelis J. A. Punt
MSMustafa Suker
Mustafa Suker
GTGeertjan van Tienhoven
Geertjan van Tienhoven
Pancreatic cancer is the fourth largest cause of cancer death in the United States and Europe with over 100,000 deaths per year in Europe alone. The overall 5-year survival ranges from 2–7 % and has hardly improved over the last two decades. Approximately 15 % of all patients have resectable disease at diagnosis, and of those, only a subgroup has a resectable tumour at surgical exploration. Data from cohort studies have suggested that outcome can be improved by preoperative radiochemotherapy, but data from well-designed randomized studies are lacking. Our PREOPANC phase III trial aims to test the hypothesis that median overall survival of patients with resectable or borderline resectable pancreatic cancer can be improved with preoperative radiochemotherapy. The PREOPANC trial is a randomized, controlled, multicentric superiority trial, initiated by the Dutch Pancreatic Cancer Group. Patients with (borderline) resectable pancreatic cancer are randomized to A: direct explorative laparotomy or B: after negative diagnostic laparoscopy, preoperative radiochemotherapy, followed by explorative laparotomy. A hypofractionated radiation scheme of 15 fractions of 2.4 gray (Gy) is combined with a course of gemcitabine, 1,000 mg/m2/dose on days 1, 8 and 15, preceded and followed by a modified course of gemcitabine. The target volumes of radiation are delineated on a 4D CT scan, where at least 95 % of the prescribed dose of 36 Gy in 15 fractions should cover 98 % of the planning target volume. Standard adjuvant chemotherapy is administered in both treatment arms after resection (six cycles in arm A and four in arm B). In total, 244 patients will be randomized in 17 hospitals in the Netherlands. The primary endpoint is overall survival by intention to treat. Secondary endpoints are (R0) resection rate, disease-free survival, time to locoregional recurrence or distant metastases and perioperative complications. Secondary endpoints for the experimental arm are toxicity and radiologic and pathologic response. The PREOPANC trial is designed to investigate whether preoperative radiochemotherapy improves overall survival by means of increased (R0) resection rates in patients with resectable or borderline resectable pancreatic cancer. Trial open for accrual: 3 April 2013 The Netherlands National Trial Register – NTR3709 (8 November 2012) EU Clinical Trials Register – 2012-003181-40 (11 December 2012)

15 February 2016 in International Journal of Colorectal Disease
Verified
Journal Article
Closed access
PDF file
BBB. C. Boer
B. C. Boer
FGFeike de Graaff
Feike de Graaff
MBM. Brusse-Keizer
M. Brusse-Keizer
DBD. E. Bouman
D. E. Bouman
CSC. H. Slump
C. H. Slump
JKJoost M. Klaase
Joost M. Klaase

1 September 2015 in European Journal of Surgical Oncology
Verified
Journal Article
Closed access
CVC.J. Verberne
C.J. Verberne
ZZZ. Zhan
Z. Zhan
EHE. van Den Heuvel
E. van Den Heuvel
IGIrene Grossmann
Irene Grossmann
PDP.M. Doornbos
P.M. Doornbos
TWT. Wiggers
T. Wiggers

1 December 2015 in British Journal of Radiology
Verified
Journal Article
Closed access
JPJoost J Pouw
Joost J Pouw
MGMaarten R Grootendorst
Maarten R Grootendorst
RBRoland Bezooijen
Roland Bezooijen
CKCaroline A H Klazen
Caroline A H Klazen
WBWieger I De Bruin
Wieger I De Bruin
BHBernard ten Haken
Bernard ten Haken
Objective:Sentinel lymph node biopsy (SLNB) with a superparamagnetic iron oxide (SPIO) tracer was shown to be non-inferior to the standard combined technique in the SentiMAG Multicentre Trial. The MRI subprotocol of this trial aimed to develop a magnetic alternative for pre-operative lymphoscintigraphy (LS). We evaluated the feasibility of using MRI following the administration of magnetic tracer for pre-operative localization of sentinel lymph nodes (SLNs) and its potential for non-invasive identification of lymph node (LN) metastases.Methods:Patients with breast cancer scheduled to undergo SLNB were recruited for pre-operative LS, single photon emission CT (SPECT)-CT and SPIO MRI. T1 weighted turbo spin echo and T2 weighted gradient echo sequences were used before and after interstitial injection of magnetic tracer into the breast. SLNs on MRI were defined as LNs with signal drop and direct lymphatic drainage from the injection site. LNs showing inhomogeneous SPIO uptake were classified as metastatic. D...

26 March 2015 in BMC Cancer
Verified
Journal Article
Open access
PDF file
NANinos Ayez
Ninos Ayez
ESEric P van der Stok
Eric P van der Stok
HWHans de Wilt
Hans de Wilt
SRSandra A Radema
Sandra A Radema
RHRichard van Hillegersberg
Richard van Hillegersberg
DGDirk Jan Grünhagen
Dirk Jan Grünhagen
Efforts to improve the outcome of liver surgery by combining curative resection with chemotherapy have failed to demonstrate definite overall survival benefit. This may partly be due to the fact that these studies often involve strict inclusion criteria. Consequently, patients with a high risk profile as characterized by Fong’s Clinical Risk Score (CRS) are often underrepresented in these studies. Conceptually, this group of patients might benefit the most from chemotherapy. The present study evaluates the impact of neo-adjuvant chemotherapy in high-risk patients with primary resectable colorectal liver metastases, without extrahepatic disease. Our hypothesis is that adding neo-adjuvant chemotherapy to surgery will provide an improvement in overall survival (OS) in patients with a high-risk profile. CHARISMA is a multicenter, randomized, phase III clinical trial. Patients will be randomized to either surgery alone (standard treatment, arm A) or to 6 cycles of neo-adjuvant oxaliplatin-based chemotherapy, followed by surgery (arm B). Patients must be ≥ 18 years of age with liver metastases of histologically confirmed primary colorectal carcinoma. Patients with extrahepatic metastases are excluded. Liver metastases must be deemed primarily resectable. Only patients with a CRS of 3–5 are eligible. The primary study endpoint is OS. Secondary endpoints are progression free survival (PFS), quality of life, morbidity of resection, treatment response on neo-adjuvant chemotherapy, and whether CEA levels can predict treatment response. CHARISMA is a multicenter, randomized, phase III clinical trial that will provide an answer to the question if adding neo-adjuvant chemotherapy to surgery will improve OS in a well-defined high-risk patient group with colorectal liver metastases. The CHARISMA is registered at European Union Clinical Trials Register (EudraCT), number: 2013-004952-39 , and in the “Netherlands national Trial Register (NTR), number: 4893.