M. W. Barentsz
Utrecht University
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Publication
Featured researches published by M. W. Barentsz.
British Journal of Surgery | 2013
M. W. Barentsz; M. A. A. J. van den Bosch; W.B. Veldhuis; P. J. van Diest; Ruud M. Pijnappel; A. J. Witkamp; Helena M. Verkooijen
Radioactive seed localization (RSL) is an alternative to wire localization for guiding surgical excision of non‐palpable breast cancer. This review provides an overview of the available evidence on the accuracy of RSL in patients undergoing breast‐conserving surgery.
Journal of Medical Internet Research | 2014
M. W. Barentsz; Hester Wessels; Paul J. van Diest; Ruud M. Pijnappel; Cees Haaring; Carmen van der Pol; Arjen J. Witkamp; Maurice A. A. J. van den Bosch; Helena M. Verkooijen
Background Electronic applications are increasingly being used in hospitals for numerous purposes. Objective Our aim was to assess differences in the characteristics of patients who choose paper versus electronic questionnaires and to evaluate the data quality of both approaches. Methods Between October 2012 and June 2013, 136 patients participated in a study on diagnosis-induced stress and anxiety. Patients were asked to fill out questionnaires at six different moments during the diagnostic phase. They were given the opportunity to fill out the questionnaires on paper or electronically (a combination of tablet and Web-based questionnaires). Demographic characteristics and completeness of returned data were compared between groups. Results Nearly two-thirds of patients (88/136, 64.7%) chose to fill out the questionnaires on paper, and just over a third (48/136, 35.3%) preferred the electronic option. Patients choosing electronic questionnaires were significantly younger (mean 47.3 years vs mean 53.5 in the paper group, P=.01) and higher educated (P=.004). There was significantly more missing information (ie, at least one question not answered) in the paper group during the diagnostic day compared to the electronic group (using a tablet) (28/88 vs 1/48, P<.001). However, in the week after the diagnostic day, missing information was significantly higher in the electronic group (Web-based questionnaires) compared to the paper group (41/48 vs 38/88, P<.001). Conclusions Younger patients and patients with a higher level of education have a preference towards filling out questionnaires electronically. In the hospital, a tablet is an excellent medium for patients to fill out questionnaires with very little missing information. However, for filling out questionnaires at home, paper questionnaires resulted in a better response than Web-based questionnaires.
American Journal of Clinical Pathology | 2014
Shona Kalkman; M. W. Barentsz; Paul J. van Diest
OBJECTIVES A systematic review of the literature was performed to identify whether minimum formalin fixation time may be reduced for reliable immunohistochemical assessment of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). METHODS PubMed, EMBASE, and the Cochrane Library were systematically searched for studies addressing effects of brief tissue fixation (<6 hours) on the analysis of ER, PR, or HER2 expression in patients with breast cancer. RESULTS Five publications reported effects of brief fixation on ER, PR, or HER2 expression. Four studies showed similar receptor expression of short fixation compared with recommended fixation time (6-72 hours). One publication found that a minimum fixation time of 6 to 8 hours is necessary for reliable ER results. CONCLUSIONS Available data on the effect of brief fixation on receptor status are limited. However, brief fixation of very highly expressing breast cancers does not seem to alter ER, PR, and HER2 status. Nevertheless, scoring inconsistencies have been observed. Further research is required in larger study populations with more low-expressing cases for future validation.
Journal of Magnetic Resonance Imaging | 2015
M. W. Barentsz; Valentina Taviani; Jung M. Chang; Debra M. Ikeda; Kanae Miyake; Suchandrima Banerjee; Maurice A. A. J. van den Bosch; Brian A. Hargreaves; Bruce L. Daniel
To compare the diagnostic value of conventional, bilateral diffusion‐weighted imaging (DWI) and high‐resolution targeted DWI of known breast lesions.
Ejso | 2015
M. W. Barentsz; Emily L. Postma; T. van Dalen; M. A. A. J. van den Bosch; Hui Miao; Paul D. Gobardhan; L.E. van den Hout; Ruud M. Pijnappel; Arjen J. Witkamp; P. J. van Diest; R. van Hillegersberg; Helena M. Verkooijen
BACKGROUND In patients undergoing breast conserving surgery for non-palpable breast cancer, obtaining tumour free resection margins is important to prevent reexcision and local recurrence. We developed a model to predict positive resection margins in patients undergoing breast conserving surgery for non-palpable invasive breast cancer. METHODS A total of 576 patients with non-palpable invasive breast cancer underwent breast conserving surgery in five hospitals in the Netherlands. A prediction model for positive resection margins was developed using multivariate logistic regression. Calibration and discrimination of the model were assessed and the model was internally validated by bootstrapping. RESULTS Positive resection margins were present in 69/576 (12%) patients. Factors independently associated with positive resection margins included mammographic microcalcifications (OR 2.14, 1.22-3.77), tumour size (OR 1.75, 1.20-2.56), presence of DCIS (OR 2.61, 1.41-4.82), Bloom and Richardson grade 2/3 (OR 1.82, 1.05-3.14), and caudal location of the lesion (OR 2.4, 1.35-4.27). The model was well calibrated and moderately able to discriminate between patients with positive versus negative resection margins (AUC 0.70, 95% CI, 0.63-0.77, and 0.69 after internal validation). CONCLUSION The presented prediction model is moderately able to differentiate between women with high versus low risk of positive margins, and may be useful for surgical planning and preoperative patient counselling.
The American Journal of Surgical Pathology | 2014
Shona Kalkman; M. W. Barentsz; Arjen J. Witkamp; Elsken van der Wall; Helena M. Verkooijen; Paul J. van Diest
In patients with invasive breast carcinoma, estrogen receptor &agr; (ER&agr;) and progesterone receptor (PR) expressions need to be assessed in core-needle biopsies (CNBs) before the start of neoadjuvant systemic treatment. Current guidelines recommend a minimum formalin fixation time of 6 hours. Considering the increasing demand for same-day diagnostics in oncology, more rapid tissue processing with shorter fixation times is required. To identify whether brief fixation (<6 h) of CNBs compared with conventionally fixed resection specimens provides for reliable immunohistochemical assessment of ER&agr; and PR expression, 78 consecutive patients diagnosed with invasive breast carcinoma were included through the same-day diagnostics programme of the UMC Utrecht. Paraffin-embedded CNBs fixed for approximately 45 minutes were retrieved. Immunohistochemistry for ER&agr; and PR was compared between the briefly fixed CNBs and conventionally fixed resection specimens. All slides were reviewed by means of consensus scoring by 2 blinded observers. Overall agreement between CNB and resections was 73/74 (98.6%) for ER&agr; (&kgr;=0.85; 95% confidence interval [CI]=0.56-1.00) and 69/75 (92.0%) for PR (&kgr;=0.81; 95% CI=0.66-0.96). For ER&agr;, positive and negative predictive values were 98.6% (95% CI=0.91-0.99) and 100.0% (95% CI=0.31-1.00), respectively. For PR, positive and negative predictive values were 100.0% (95% CI=0.91-1.00) and 76.0% (95% CI=0.54-0.90). In conclusion, analysis of hormone receptor expression in briefly fixed CNB seems comparable to results from conventionally fixed resection specimens of the same tumor.
Radiology Research and Practice | 2011
M. W. Barentsz; Evert-Jan Vonken; J. A. van Herwaarden; Luke P. H. Leenen; W.P.Th.M. Mali; M. A. A. J. van den Bosch
Purpose. To analyse the technical success of pelvic embolization in our institution and to assess periprocedural hemodynamic status and morbidity/mortality of all pelvic trauma patients who underwent pelvic embolization. Methods. A retrospective analysis of patients with a pelvic fracture due to trauma who underwent arterial embolization was performed. Clinical data, pelvic radiographs, contrast-enhanced CT-scans, and angiographic findings were reviewed. Subsequently, the technical success and peri-procedural hemodynamic status were evaluated and described. Results. 19 trauma patients with fractures of the pelvis underwent arterial embolization. Initially, 10/19 patients (53%) were hemodynamically unstable prior to embolization. Technical success of embolization was 100%. 14/19 patients (74%) were stable after embolization, and treatment success was high as 74%. Conclusion. Angiography with subsequent embolization should be performed in patients with a pelvic fracture due to trauma and hemodynamic instability, after surgical intervention or with a persistent arterial blush indicative of an active bleeding on CT.
Cancer Research | 2013
M. W. Barentsz; Emily L. Postma; T. van Dalen; M. A. A. J. van den Bosch; M Hui; Paul D. Gobardhan; A. J. Witkamp; P. J. van Diest; J.M. van Gorp; R. van Hillegersberg; Helena M. Verkooijen
Background Obtaining tumor free resection margins is essential in patients undergoing breast conserving surgery. Several risk factors associated with positive margins are described in literature. We developed a prediction model to predict positive resection margins in patients undergoing breast conserving surgery of non-palpable lesions. Methods A total of 576 patients with non-palpable invasive breast cancer underwent breast conserving surgery at five different hospitals in the Netherlands. A prediction model for positive resection margins was built using multivariate regression analysis and internally validated by bootstrapping. Results Positive resection margins were present in 69/576 (12%) patients. Factors associated with positive margins included microcalcifications on mammography (OR 1.8, 1.0-3.2), tumor not visible on ultrasound (OR 2.6, 1.2-5.6), presence of DCIS (OR 2.3, 1.3-4.0), multifocality (OR 3.5, 1.0-12.1), caudal location in the breast (OR 1.9, 1.1-3.5), and invasive tumor size (OR 1.83, 1.6-2.7). Together, these factors were able to moderately discriminate between patients with positive versus negative margins (area under the ROC 0.71, 95% CI 0.648 – 0.780). After internal validation the discrimination was slightly lower with an AUC of 0.694. Prevalence of positive margins was 5.2% in the highest risk quintile versus 26.3% in the lowest quintile. Conclusion A model predicting positive resection margins after breast conserving surgery in non-palpable breast cancer was built. This model is moderately able to differentiate between women with high versus low risk of positive margins, and may be useful for surgical planning (eg. preoperative MRI) and informing of patients. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-15-03.
Cancer Research | 2012
M. W. Barentsz; T. van Dalen; Paul D. Gobardhan; Vivian Bongers; C.I. Perre; Ruud M. Pijnappel; M. A. A. J. van den Bosch; Helena M. Verkooijen
Background: The effectiveness of intraoperative ultrasound (IOUS) for preoperative localization of non-palpable breast cancers within the operation theatre has not been studied extensively. In this prospective cohort study, we compared margin status, re-excision rate and excised volume of IOUS to guidewire localization (GWL). Methods: A total of 258 consecutive patients with non-palpable invasive breast cancer underwent breast conserving surgery between 1999–2010. GWL was performed in 138 (54%) and IOUS in 120 (46%) patients. Tumour dimensions, resection volume, margin status and re-excision rates were compared by means of multivariate regression analysis. Calculated resection ratios, i.e. indicating the amount of excess tissue resection, were calculated by dividing the total resection volume by the optimal resection volume (the tumor diameter plus a 1.0 cm margin) and compared between the groups. Results: The groups were similar in terms of age, histological subtype and presence of DCIS. Lesions in the IOUS group were larger (1.24 vs. 0.98 cm), while lesions in the GWL group consisted more often of microcalcifications only (19% vs. 3%). Tumour free resection margins were obtained in more than 93% of patients (93.5% with GWL vs. 93.3% with IOUS, P = .958) and re-excision was performed in 11.0% of patients undergoing GWL and 12.5% of patients undergoing IOUS ( P = .684). In both groups, resection volumes were similar, but IOUS led to more optimal tissue resection (calculated resection ratio 4.33 vs 3.30, P = .018). After adjustment for tumor diameter, radiological findings and presence of DCIS, the difference in calculated resection volumes was no longer significant. Conclusion: For localization of non-palpable breast cancer, IOUS is a reliable alternative to GWL, as it achieves similar results in terms of complete tumour removal, re-excision rate and excised volume. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-14-08.
Breast Cancer Research and Treatment | 2012
M. W. Barentsz; T. van Dalen; Paul D. Gobardhan; Vivian Bongers; C.I. Perre; Ruud M. Pijnappel; M. A. A. J. van den Bosch; Helena M. Verkooijen