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Featured researches published by Robert-Jan Schipper.


Investigative Radiology | 2013

Noninvasive nodal staging in patients with breast cancer using gadofosveset-enhanced magnetic resonance imaging: a feasibility study.

Robert-Jan Schipper; Marjolein L. Smidt; L.M. van Roozendaal; C.J. Castro; B. de Vries; E.M. Heuts; Kristien Keymeulen; Joachim E. Wildberger; M. B. I. Lobbes; Regina G. H. Beets-Tan

ObjectivesThe objectives of this study were to evaluate whether the axillary lymph nodes show enhancement on magnetic resonance imaging (MRI) after gadofosveset administration, to assess the time to peak enhancement, and to determine the diagnostic performance of gadofosveset-enhanced MRI for axillary nodal staging. Materials and MethodsTen women whose conditions had been diagnosed with invasive breast cancer (>2 cm) underwent both nonenhanced and gadofosveset-enhanced 3-dimensional T1-weighted axillary MRI. Signal intensity of the axillary lymph nodes and different adjacent tissues was measured, and relative signal intensity (rSI) was calculated. A Wilcoxon signed rank test was used to compare results of rSI between different time intervals. A radiologist evaluated all lymph nodes with regard to size, morphologic features, and gadofosveset uptake. All MRI-depicted lymph nodes were matched with the lymph nodes that were removed during surgery. Nodal status was investigated by a pathologist. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of gadofosveset-enhanced MRI for axillary lymph node staging were calculated. ResultsAfter contrast administration, a significant signal increase was observed in the lymph nodes (P < 0.05). When compared with muscle or fat, rSI of the lymph nodes demonstrated a significant postcontrast peak enhancement between 11 minutes and 30 seconds and 20 minutes and 50 seconds (P < 0.05). A total of 152 lymph nodes were harvested during sentinel lymph node biopsy or axillary lymph node dissection, of which 116 were matched with the lymph nodes that were depicted on MRI. Histopathological examination resulted in 21 macrometastases and 8 micrometastases. Using contrast-enhanced MRI, 20 lymph nodes were rated as true positive; 83 as true negative; 4 as false positive; and 9 as false negative. This resulted in an overall node-by-node sensitivity, specificity, PPV, and NPV of 69%, 95%, 83%, and 90%, respectively. If the micrometastases were excluded from the analysis, MRI showed a sensitivity of 86% and a specificity of 94%. Calculated PPV and NPV were 75% and 97%, respectively. ConclusionsThe axillary lymph nodes show enhancement on MRI after gadofosveset administration, with a peak enhancement between 11 minutes and 30 seconds and 20 minutes and 50 seconds. Diagnostic performance of gadofosveset-enhanced axillary lymph node imaging in patients with breast cancer is promising, but further studies need to confirm these results.


Ejso | 2015

The diagnostic performance of sentinel lymph node biopsy in pathologically confirmed node positive breast cancer patients after neoadjuvant systemic therapy: A systematic review and meta-analysis

T. Van Nijnatten; Robert-Jan Schipper; Marc Lobbes; Patty J. Nelemans; Regina G. H. Beets-Tan; Marjolein L. Smidt

PURPOSE To provide a systematic review and meta-analysis of studies investigating sentinel lymph node biopsy after neoadjuvant systemic therapy in pathologically confirmed node positive breast cancer patients. METHODS Pubmed and Embase databases were searched until June 19th, 2015. All abstracts were read and data extraction was performed by two independent readers. A random-effects model was used to pool the proportion for identification rate, false-negative rate (FNR) and axillary pCR with 95% confidence intervals. Subgroup analyses affirmed potential confounders for identification rate and FNR. RESULTS A total of 997 abstracts were identified and eventually eight studies were included. Pooled estimates were 92.3% (90.8-93.7%) for identification rate, 15.1% (12.7-17.6%) for FNR and 36.8% (34.2-39.5%) for axillary pCR. After subgroup analysis, FNR is significantly worse if one sentinel node was removed compared to two or more sentinel nodes (23.9% versus 10.4%, p = 0.026) and if studies contained clinically nodal stage 1-3, compared to studies with clinically nodal stage 1-2 patients (21.4 versus 13.1%, p = 0.049). Other factors, including single tracer mapping and the definition of axillary pCR, were not significantly different. CONCLUSION Based on current evidence it seems not justified to omit further axillary treatment in every clinically node positive breast cancer patients with a negative sentinel lymph node biopsy after neoadjuvant systemic therapy.


European Journal of Radiology | 2015

Noninvasive nodal restaging in clinically node positive breast cancer patients after neoadjuvant systemic therapy: A systematic review

Robert-Jan Schipper; M. Moossdorff; Regina G. H. Beets-Tan; Marjolein L. Smidt; M. B. I. Lobbes

OBJECTIVE To provide a systematic review of studies comparing the diagnostic performance of noninvasive techniques and axillary lymph node dissection in the identification of initially node positive patients with pathological complete response of axillary lymph nodes to neoadjuvant systemic therapy. METHODS PubMed and Embase databases were searched until May 21st, 2014. First, duplicate studies were eliminated. Next, study abstracts were read by two readers to assess eligibility. Studies were selected based on predefined inclusion criteria. Of these, data extraction was performed by two readers independently. RESULTS Of the 987 abstracts that were considered for inclusion, four were eligible for final analysis, which included a total of 572 patients. The diagnostic performance of clinical examination, axillary ultrasound, breast MRI, whole body (18)F-FDG PET-CT, and a prediction model to identify patients with pathological complete response were investigated. Studies were often limited by small sample size. Furthermore, systemic therapy regimens and definitions of clinical and pathological complete response were variable, refraining further pooling of data. The reported positive predictive value of different techniques to identify patients with axillary pathological complete response after neoadjuvant systemic therapy varied between 40% and 100%. CONCLUSION At present, there is no accurate noninvasive restaging technique able to identify patients with complete axillary response after neoadjuvant systemic therapy.


Clinical Breast Cancer | 2014

A model to predict pathologic complete response of axillary lymph nodes to neoadjuvant chemo(immuno)therapy in patients with clinically node-positive breast cancer.

Robert-Jan Schipper; M. Moossdorff; Patty J. Nelemans; G.A.P. Nieuwenhuijzen; Bart de Vries; Luc J.A. Strobbe; Rudi M. H. Roumen; Franchette van den Berkmortel; Vivianne C. G. Tjan-Heijnen; Regina G. H. Beets-Tan; Marc Lobbes; Marjolein L. Smidt

BACKGROUND Between 20% and 42% of patients with clinically node-positive breast cancer achieve a pathologic complete response (pCR) of axillary lymph nodes after neoadjuvant chemotherapy or immunotherapy, or both, (chemo[immuno]therapy). Hypothetically, axillary lymph node dissection (ALND) may be safely omitted in these patients. This study aimed to develop a model for predicting axillary pCR in these patients. PATIENTS AND METHODS We retrospectively identified patients with clinically node-positive breast cancer who were treated with neoadjuvant chemo(immuno)therapy and ALND between 2005 and 2012 in 5 hospitals. Patient and tumor characteristics, neoadjuvant chemo(immuno)therapy regimens, and pathology reports were extracted. Binary logistic regression analysis was used to predict axillary pCR with the following variables: age, tumor stage and type, hormone receptor and human epidermal growth factor receptor 2 (HER2) status, and administration of taxane and trastuzumab. The model was internally validated by bootstrap resampling. The overall performance of the model was assessed by the Brier score and the discriminative performance by receiver operating characteristic (ROC) curve analysis. RESULTS A model was developed based on 291 patients and was internally validated with a scaled Brier score of 0.14. The area under the ROC curve of this model was 0.77 (95% confidence interval [CI], 0.71-0.82). At a cutoff value of predicted probability ≥ 0.50, the model demonstrated specificity of 88%, sensitivity of 43%, positive predictive value (PPV) of 65%, and negative predictive value (NPV) of 75%. CONCLUSION This prediction model shows reasonable accuracy for predicting axillary pCR. However, omitting axillary treatment based solely on the nomogram score is not justified. Further research is warranted to noninvasively identify patients with axillary pCR.


Radiology | 2015

Diagnostic Performance of Dedicated Axillary T2- and Diffusion-weighted MR Imaging for Nodal Staging in Breast Cancer

Robert-Jan Schipper; Marie-Louise Paiman; Regina G. H. Beets-Tan; Patricia J. Nelemans; Bart de Vries; E.M. Heuts; Koen K. Van de Vijver; Kristien Keymeulen; Boudewijn Brans; Marjolein L. Smidt; Marc Lobbes

PURPOSE To evaluate the diagnostic performance of unenhanced axillary T2-weighted and diffusion-weighted (DW) magnetic resonance (MR) imaging for axillary nodal staging in patients with newly diagnosed breast cancer, with node-by-node and patient-by-patient validation. MATERIALS AND METHODS Institutional review board approval and informed consent were obtained. Fifty women (mean age, 60 years; range, 22-80 years) underwent high-spatial-resolution axillary 3.0-T T2-weighted imaging without fat suppression and DW imaging (b = 0, 500, and 800 sec/mm(2)), followed by either sentinel lymph node biopsy (SLNB) or axillary lymph node dissection. Two radiologists independently scored each lymph node on a confidence level scale from 0 (benign) to 4 (malignant), first on T2-weighted MR images, then on DW MR images. Two researchers independently measured the mean apparent diffusion coefficient (ADC) of each lymph node. Diagnostic performance parameters were calculated on the basis of node-by-node and patient-by-patient validation. RESULTS With respective node-by-node and patient-by-patient validation, T2-weighted MR imaging had a specificity of 93%-97% and 87%-95%, sensitivity of 32%-55% and 50%-67%, negative predictive value (NPV) of 88%-91% and 86%-89%, positive predictive value (PPV) of 60%-70% and 62%-75%, and area under the receiver operating characteristic curve (AUC) of 0.78 and 0.80-0.88, with good interobserver agreement (κ = 0.70). The addition of DW MR imaging resulted in lower specificity (59%-88% and 50%-84%), higher sensitivity (45%-64% and 75%-83%), comparable NPV (89% and 90%-91%), lower PPV (23%-42% and 34%-60%), and lower AUC (0.68-0.73 and 0.70-0.86). ADC measurement resulted in a specificity of 63%-64% and 61%-63%, sensitivity of 41% and 67%, NPV of 85% and 85%-86%, PPV of 18% and 35%-36%, and AUC of 0.54-0.58 and 0.69-0.74, respectively, with excellent interobserver agreement (intraclass correlation coefficient, 0.83). CONCLUSION Dedicated high-spatial-resolution axillary T2-weighted MR imaging showed good specificity on the basis of node-by-node and patient-by-patient validation, with good interobserver agreement. However, its NPV is still insufficient to substitute it for SLNB for exclusion of axillary lymph node metastasis. DW MR imaging and ADC measurement were of no added value.


The Breast | 2013

No increase of local recurrence rate in breast cancer patients treated with skin-sparing mastectomy followed by immediate breast reconstruction

D.R.J. van Mierlo; T.R. Lopez Penha; Robert-Jan Schipper; M.H. Martens; J. Serroyen; Marc Lobbes; E.M. Heuts; Stefania Tuinder; Marjolein L. Smidt

BACKGROUND The aim of this study was to evaluate the incidence of local recurrence after SSM with IBR and to determine whether complications lead to postponement of adjuvant therapy. METHOD Patients that underwent IBR after SSM between 2004 and 2011 were included. RESULTS A total of 157 reconstruction procedures were performed in 147 patients for invasive breast cancer (n = 117) and ductal carcinoma in situ (n = 40). The median follow-up was 39 months [range 6-97]. Estimated 5-year local recurrence rate was 2.9% (95% CI 0.1-5.7). The median time to start adjuvant therapy was 27.5 days [range 19-92] in 18 patients with complications, and 23.5 days [range 8-54] in 46 patients without complications (p = 0.025). CONCLUSION In our single-institution cohort, IBR after SSM carried an acceptable local recurrence rate. Complications caused a delay of adjuvant treatment but this was within guidelines and therefore not clinically relevant.


Annals of Surgery | 2017

Trends on Axillary Surgery in Nondistant Metastatic Breast Cancer Patients Treated Between 2011 and 2015: A Dutch Population-based Study in the Acosog-z0011 and Amaros Era

Ingrid G.M. Poodt; P.E.R. Spronk; Guusje Vugts; Thijs van Dalen; M.T.F.D. Vrancken Peeters; Marjolijn L. Rots; A. Kuijer; G.A.P. Nieuwenhuijzen; Robert-Jan Schipper

Objectives: To evaluate patterns of care in axillary surgery for Dutch clinical T1-4N0M0 (cT1-4N0M0) breast cancer patients and to assess the effect of the American College for Surgeons Oncology Group (ACOSOG)-Z0011 and After Mapping of the Axilla: Radiotherapy Or Surgery (AMAROS) trial on axillary surgery patterns in Dutch cT1-2N0M0 sentinel node positive breast cancer patients. Background: Since publication of the ACOSOG-Z0011 and AMAROS trial, omitting a completion axillary lymph node dissection (cALND) in sentinel node positive breast cancer patients is proposed in selected patients. Methods: Data were obtained from the nationwide Nationaal Borstkanker Overleg Nederland breast cancer audit. Descriptive analyses were used to demonstrate trends in axillary surgery. Multivariable logistic regression analyses were used to identify factors associated with the omission of cALND in cT1-2N0M0 sentinel node-positive breast cancer patients. Results: Between 2011 and 2015 in cT1-4N0M0 breast cancer patients, the use of sentinel lymph node biopsy as definitive axillary staging increased from 72% to 93%, and (c)ALND as definitive axillary staging decreased from 24% to 6% (P < 0.001). The use of cALND decreased from 75% to 17% in cT1-2N0 sentinel node-positive patients (P < 0.001). Earlier year of diagnosis, lower age, primary mastectomy, invasive lobular subtype, increasing tumor grade, and treatment in a nonteaching hospital were associated with a lower probability of omitting cALND (P < 0.001). Conclusions: This study shows a trend towards less extensive axillary surgery in Dutch cT1-T4N0M0 breast cancer patients; illustrated by an overall increase of sentinel lymph node biopsy and decrease in cALND. Despite this trend, particularly noticed in cT1-2N0 sentinel node-positive patients after publication of the ACOSOG-Z0011 and AMAROS trial, variations in patterns of care in axillary surgery are still present.


Clinical Radiology | 2018

Diagnostic performance of gadofosveset-enhanced axillary MRI for nodal (re)staging in breast cancer patients: results of a validation study

T. Van Nijnatten; Robert-Jan Schipper; M. B. I. Lobbes; L.M. van Roozendaal; Stefan Vöö; M. Moossdorff; M.-L. Paiman; B. de Vries; Kristien Keymeulen; Joachim E. Wildberger; Marjolein L. Smidt; Regina G. H. Beets-Tan

AIM To evaluate diagnostic performance of gadofosveset (GDF)-enhanced magnetic resonance imaging (MRI) in addition to T2-weighted (T2W) MRI for nodal (re)staging in newly diagnosed breast cancer patients. MATERIALS AND METHODS Ninety patients underwent axillary T2W- and GDF-MRI. Two radiologists independently scored each lymph node; first on T2W-MRI, subsequently adjusting their score on GDF-MRI. Diagnostic performance parameters were calculated on node-by-node and patient-by-patient validation with histopathology as the reference standard. Furthermore, learning curve analysis for reading GDF-MRI was performed. RESULTS In patient-by-patient validation, overall reader performances for T2W- and GDF-MRI were similar with area under the receiver operating characteristic curves (AUC) of 0.75 and 0.77 (p=0.731) for reader 1 and 0.79 and 0.72 (p=0.156) for reader 2. For node-by-node validation, AUC values of T2W- and GDF-MRI were 0.76 and 0.82 (p=0.018) and 0.77 and 0.77 (p=0.998) for reader 1 and 2. The AUC for reader 1 was 0.71 for first one-third of nodes evaluated, improving to 0.80 and 0.95 for the next and last one-third, respectively. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) improved from 38%, 89%, 56%, and 79% to 60%, 93%, 64%, and 92%. The AUC of reader 2 improved from 0.69 to 0.79. CONCLUSION The present study confirmed that GDF-MRI, in addition to T2W-MRI, has potential as a non-invasive method for nodal (re)staging in breast cancer.


European Journal of Cancer | 2012

96 A Retrospective Analysis of Follow-up in Patients with Suspicion of Breast Tissue Superposition in Digital Screening Mammograms

L.M. van Roozendaal; Robert-Jan Schipper; M. Van Goethem; Marjolein L. Smidt; M. B. I. Lobbes

concentration during NAC, while no trend was observed in oxyhemoglobin, deoxyhemoglobin, and bulk lipid. The percent change in water after two to three months of chemotherapy correlates strongly with age (r=0.752, p = 0.0019). Conclusion: Water concentration correlated with the MRI fibroglandular density. Ovarian suppression induced by NAC may be responsible for the reduced breast density, explaining the significant water concentration reduction in premenopausal subjects. No significant changes were noted in bulk lipid in any subject. This suggests that relatively fast changes in breast density induced by NAC occur due to the reduction of fibroglandular tissue rather than by increases or replacement by bulk lipid. These results suggest that DOSI is a low-cost, bed-side imaging modality capable of monitoring breast density as a prognostic marker.


Insights Into Imaging | 2013

The role of magnetic resonance imaging in assessing residual disease and pathologic complete response in breast cancer patients receiving neoadjuvant chemotherapy: a systematic review

Marc Lobbes; R. Prevos; Marjolein L. Smidt; Vivianne C. G. Tjan-Heijnen; M. Van Goethem; Robert-Jan Schipper; Regina G. H. Beets-Tan; Joachim E. Wildberger

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L.M. van Roozendaal

Maastricht University Medical Centre

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