Peter Bult

Radboud University Medical Centre (Radboudumc), Nymegen, Gelderland, Netherlands

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Publications (70)364.14 Total impact

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    ABSTRACT: The insulin-like growth factor 1 receptor (IGF-1R) may be involved in the development of resistance against conventional cancer treatment. The aim of this study was to assess whether IGF-1R expression of breast tumors changes during neoadjuvant therapy and to study whether these changes were associated with survival. Paraffin embedded tumor tissue was collected from pretreatment biopsies and surgical resections of 62 breast cancer patients who were treated with neoadjuvant chemotherapy or endocrine therapy. IGF-1R expression was determined immunohistochemically and compared before and after treatment. High membranous IGF-1R expression at diagnosis correlated significantly with ER positivity, low tumor stage (stage I/II) and longer overall survival (p < 0.05). After neoadjuvant treatment, membranous IGF-1R expression remained the same in 41 (65%) tumors, was upregulated in 11 (18%) tumors and downregulated in 11 (18%) tumors. Changes in membranous IGF-1R expression were associated with overall survival (log-rank test: p = 0.013, multivariate cox-regression: p = 0.086). Mean overall survival time for upregulation, no change, and downregulation in IGF-1R expression was 3.0 ± 0.5 years, 7.3 ± 1.0 years and 15.0 ± 1.8 years, respectively. Changes in other parameters were not significantly associated with survival. Neoadjuvant therapy can induce changes in IGF-1R expression. Upregulation of IGF-1R expression after neoadjuvant treatment is a poor prognostic factor in breast cancer patients, providing a rationale for incorporating anti-IGF-1R drugs in the management of these patients.
    PLoS ONE 02/2015; 10(2):e0117745. DOI:10.1371/journal.pone.0117745 · 3.53 Impact Factor
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    ABSTRACT: MUTYH-associated polyposis (MAP) is an autosomal recessive disease, which predisposes to polyposis and colorectal cancer. There is a trend towards an increased risk of breast cancer in MAP patients, with a remarkable proportion of papillary breast cancers. To determine whether MUTYH mutations are associated with this specific and rare type of breast cancer, 53 unselected patients with papillary breast cancer were analyzed for founder mutations in the MUTYH gene. No germline mutations were identified, indicating that biallelic MUTYH mutations are not a frequent underlying cause for the development of papillary carcinomas of the breast.
    Hereditary Cancer in Clinical Practice 12/2014; 12(1). DOI:10.1186/1897-4287-12-21 · 2.10 Impact Factor
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    ABSTRACT: Depth of invasion is an important prognostic factor for patients with vulvar squamous cell carcinoma. The aim of this study was to identify the most optimal method of measuring the depth of invasion in relation to the individual outcome in patients with vulvar squamous cell carcinoma. Data of 175 consecutive patients with a primary vulvar squamous cell carcinoma with known lymph node status, treated in the Radboud University Medical Center, the Netherlands (2000-2010), were stored in a database. At pathology review of 148 (85%) cases, depth of invasion was measured using the conventional and alternative methods. Clinical and pathological characteristics of patients with a change in FIGO stage were compared with those without a change in stage. In 148 vulvar squamous cell carcinoma patients, the median depth of invasion was shown to be decreased from 5.5 mm (range 1.1-20) using the conventional method to 3.6 mm (range 0.2-20) using the alternative method (P<0.05). This led to a change in the FIGO stage in 13 of the 148 (9%) patients and a change in depth of invasion from 3.5 to 0.2 mm in one patient (1%) with FIGO stage IIIA. Of all 69 stage 1B patients, 13 (19%) were downstaged to stage IA. The downstaged patients developed less recurrences (15% vs 39%) and had a higher disease-specific survival (100% vs 84%) compared with the patients who remained FIGO stage IB. Using the alternative method for measuring the depth of invasion in tumors of vulvar squamous cell carcinoma patients, 19% of the patients with a FIGO stage IB tumor might be treated without groin surgery resulting in less treatment-related morbidity. The results are promising but more prospective data on a higher number of patients are necessary.Modern Pathology advance online publication, 5 September 2014; doi:10.1038/modpathol.2014.103.
    Modern Pathology 09/2014; 28(2). DOI:10.1038/modpathol.2014.103 · 6.36 Impact Factor
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    ABSTRACT: AimsImmunohistochemical assessment of Ki67 expression in core-needle biopsies (CNBs) is increasingly playing a role in therapeutic decision-making for breast cancer patients. Within the framework of same-day diagnosis of breast lesions, fixation times are markedly decreased. We therefore attempted to validate Ki67 analysis in briefly fixed breast cancer CNBs.Methods and resultsCNBs of 136 consecutive patients with invasive breast cancer diagnosed through the same-day diagnosis programme of both the University Medical Centre Utrecht (UMCU) and the Radboud University Medical Centre (RUMC) were included. CNBs were fixed in formaldehyde for approximately 45 min at the UMCU and for between 60 min and 90 min at the RUMC. Immunohistochemistry for Ki67 expression was compared between the briefly fixed CNBs and conventionally fixed resection specimens of the same tumour. The overall agreement between CNBs and resections was 122 of 142 (85.9%) (κ = 0.71; 95% CI 0.60–0.83). Positive and negative predictive values were 79.7% (95% CI 67–88%) and 91.0% (95% CI 82–96%), respectively.Conclusions Overall agreement for Ki67 expression was good between briefly fixed CNBs and conventionally fixed resection specimens, and within the range of studies comparing conventionally fixed CNBs and resections.This article is protected by copyright. All rights reserved.
    Histopathology 09/2014; 66(3). DOI:10.1111/his.12521 · 3.30 Impact Factor
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    ABSTRACT: The distinction between primary gastric adenocarcinoma and gastric metastatic breast carcinoma can be difficult. Expression of hepatocyte nuclear factor 4A (HNF4A) has been described as being specific to distinguish between neoplastic gastric and breast epithelial cells. The aim of this study was to validate the use of HNF4A with immunohistochemistry in discriminating gastric from breast carcinomas. Immunohistochemical expressions of HNF4A, estrogen receptor (ER), progesterone receptor (PR), and BRST-2 were determined in primary sporadic gastric adenocarcinomas (n = 107) and breast carcinomas (n = 105). The same markers and clinicopathological features were studied in 1 patient with breast metastasis of gastric cancer, 6 patients with gastric metastases of breast cancer, and 13 patients with both primary gastric and breast carcinomas. HNF4A expression was seen in 106 of 107 primary gastric adenocarcinomas and was absent in all 105 primary breast carcinomas (sensitivity 99 %, specificity 100 %). ER, PR, and BRST-2 were 100 % specific for breast carcinomas with sensitivities of 77, 58, and 38 %, respectively. The metastasis of gastric carcinoma to the breast showed strong expression of HNF4A. None of the metastases of breast carcinomas to the stomach showed expression of HNF4A. Tissues of patients with two primary carcinomas showed strong expression of HNF4A in all gastric carcinomas and no expression in breast carcinomas. Our results indicate that HNF4A is a very good marker to discriminate between primary and metastatic gastric and breast carcinomas.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 04/2014; 464(6). DOI:10.1007/s00428-014-1574-x · 2.56 Impact Factor
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    ABSTRACT: PURPOSE To assess the correlation between time to enhancement (TTE) and tumor grade using an ultrafast DCE MR Mammography protocol. METHOD AND MATERIALS 1031 patients underwent contrast enhanced breast MRI at 3.0T (Siemens, Magneton Trio and Skyra) using a 16 channel bilateral breast coil. A bi-temporal protocol was employed, interleaving a TWIST (Time-resolved angiography With Stochastic Trajectories) sequence during and immediately after IV administration of 0.1mmol/kg Gd-DOTA (20 time points, spatial resolution 1*0.9*2.5 mm, temporal resolution 4.32 seconds). 102 consecutive patients with invasive ductal (IDC) or lobular (ILC) carcinoma were included in this analysis. The TTE was determined on maximum intensity projections from the TWIST acquisitions as displayed on a dedicated DynaCAD breast MRI workstation (InVivo). TTE was defined as “the timepoint where the lesion started to enhance” minus “the time point where the aorta started to enhance”. For different tumor histology and grade categories the mode TTE was calculated and TTE distribution was compared using one way anova. RESULTS Mode TTE was 4.3 sec for 32 grade III IDC, 8.6 sec for 40 grade II IDC and 18 ILC and 12.9 sec for 12 grade I IDC. There was no significant difference in TTE between IDC and ILC (p=0.465). In IDC TTE distribution was significantly different between tumor grade categories (p<0.001). CONCLUSION TTE provides a non-invasive method to predict histological grade. Lesions that enhance very rapidly are more likely high grade than lesions that enhance relatively slow. CLINICAL RELEVANCE/APPLICATION Breast cancer therapy is dictated by pathological features of the tumor with the poorest prognosis. Because pathology is subject to sampling errors, TTE can be used to ascertain sampling of the most relevant part of the tumor.
    Radiological Society of North America 2013 Scientific Assembly and Annual Meeting; 12/2013
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    ABSTRACT: Non-SN prediction models are frequently used in clinical decision making to identify patients that may not need axillary treatment, but these models still need to be validated by follow-up data. Our purpose was the validation of non-sentinel node (SN) prediction models in predicting regional recurrences in patients without axillary treatment. We followed a cohort of 486 women with favorable primary tumor characteristics and pN0(i+)(sn) or pN1mi(sn) for median 4.5 years. None of the patients underwent axillary treatment. Based on four published non-SN prediction models, the threshold allowing separation into low versus high-risk on non-SN involvement was set at 10%. Overall 5-year regional recurrence rate was 3.0% (SE, ±0.1%). Using the Tenon scoring system, 438 low-risk patients had a 5-year regional recurrence rate of 2.3% (±0.8%), and 48 high-risk patients a recurrence rate of 10.1% (±0.4%). The MSKCC nomogram identified 300 low-risk patients with a recurrence rate of 2.8% (±1.1%), versus 166 high-risk patients with a rate of 3.4% (±0.5%) (20 patients not assessable). The Stanford nomogram identified 21 high-risk patients without recurrence, and 465 low-risk patients with a 3.2% (±0.9%) recurrence rate. A Dutch model discriminated between 384 low-risk patients with a recurrence rate of 2.2% (±0.8%) and 102 high-risk patients with a rate of 6.3% (±2.9%). The Tenon scoring system outperformed the other models as it identified the largest subgroup of patients with low recurrence rate. In patients resembling our cohort we would recommend axillary treatment if they had a Tenon score above 3.5.
    European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 10/2013; DOI:10.1016/j.ejso.2013.09.006 · 2.89 Impact Factor
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    ABSTRACT: Yes Associated Protein (YAP) has been implicated in the control of organ size by regulating cell proliferation and survival. YAP is a transcriptional coactivator that controls cellular responses through interaction with TEAD transcription factors in the nucleus, while its transcriptional functions are inhibited by phosphorylation-dependent translocation to the cytosol. YAP overexpression has been associated with different types of cancer, such as lung, skin, prostate, ovary and liver cancer. Recently, YAP was linked to E-cadherin-dependent regulation of contact inhibition in breast cancer cells. In this study we examined YAP protein expression and cellular localization in 237 cases of human invasive breast cancer by immunohistochemistry and related its expression to clinicopathological features and E-cadherin expression. We observed that invasive lobular carcinoma is characterized by higher expression levels of both nuclear and cytosolic YAP (p < 0.001). Nuclear YAP expression did not associate with other variables such as lymph node involvement, tumor grade, tumor size, mitotic activity or the molecular sub-types of invasive breast cancer. We observed that high nuclear and cytosolic YAP expression are associated with the E-cadherin deficient breast cancer subtype ILC (p < 0.001) and cell lines derived from human breast cancers and conditional mouse models of human lobular breast cancer. Since our data indicate that nuclear YAP localization is more common in breast cancers lacking functional adherens junctions, it suggests that YAP-mediated transcription may be involved in the development and progression of invasive lobular breast cancer.
    08/2013; 36(5). DOI:10.1007/s13402-013-0143-7
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    ABSTRACT: OBJECTIVE: To assess the value of breast MRI in size assessment of breast cancers in high risk patients, including those with a BRCA 1 or 2 mutation. Guidelines recommend invariably breast MRI screening for these patients and therapy is thus based on these findings. However, the accuracy of breast MRI for staging purposes is only tested in sporadic cancers. METHODS: We assessed concordance of radiologic staging using MRI with histopathology in 49 tumors in 46 high risk patients (23 BRCA1, 12 BRCA2 and 11 Non-BRCA patients). The size of the total tumor area (TTA) was compared to pathology. In invasive carcinomas (n=45) the size of the largest focus (LF) was also addressed. RESULTS: Correlation of MRI measurements with pathology was 0.862 for TTA and 0.793 for LF. TTA was underestimated in 8(16%), overestimated in 5(10%), and correctly measured in 36(73%) cases. LF was underestimated in 4(9%), overestimated in 5(11%), and correctly measured in 36(80%) cases. Impact of BRCA 1 or 2 mutations on the quality of size estimation was not observed. CONCLUSIONS: Tumor size estimation using breast MRI in high risk patients is comparable to its performance in sporadic cancers. Therefore, breast MRI can safely be used for treatment planning.
    European journal of radiology 04/2013; 82(9). DOI:10.1016/j.ejrad.2013.03.003 · 2.16 Impact Factor
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    ABSTRACT: BACKGROUND: Internationally, there is no consensus on the pathology protocol to be used to examine the sentinel lymph node (SN) in breast cancer patients. Previously, we reported that ultra-staging led to more axillary lymph node dissections (ALND). The question was, whether ultra-staging is effective in reducing the risk of regional relapse. METHODS: From January 2002 to July 2003, 541 patients from 4 hospitals were prospectively registered when they underwent a SN biopsy. In hospitals A, B, and C, 3 levels of the SN were examined pathologically, whereas in hospital D at least 7 additional levels were examined. Patients with a positive SN, including isolated tumor cells, underwent an ALND. This analysis focuses on the 341 patients with a negative SN. Primary endpoint was 5-year regional recurrence rate. RESULTS: In hospital D 34% of the patients had a negative SN as compared to 71% in hospitals A, B, and C combined (p < 0.001). At 5 years follow-up, 9 (2.6%) patients had developed a regional lymph node relapse. In hospital D none of the patients had a regional recurrence, as compared to 9 (2.9%) cases of recurrence in hospitals A, B, and C. CONCLUSION: The less intensified SN pathology protocol appeared to be associated with a slightly increased risk of regional recurrence. The absolute risk was still less than 3%, and does not seem to justify the intensified SN pathology protocol of hospital D.
    European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 02/2013; 39(5). DOI:10.1016/j.ejso.2013.02.013 · 2.89 Impact Factor
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    ABSTRACT: No published data concerning intraobserver and interobserver variability in the histopathological diagnosis of differentiated vulvar intraepithelial neoplasia (DVIN) are available, although it is widely accepted to be a subtle and difficult histopathological diagnosis. In this study, the reproducibility of the histopathological diagnosis of DVIN is evaluated. Furthermore, we investigated the possible improvement of the reproducibility after providing guidelines with histological characteristics and tried to identify histological characteristics that are most important in the recognition of DVIN. A total number of 34 hematoxylin and eosin-stained slides were included in this study and were analyzed by six pathologists each with a different level of education. Slides were reviewed before and after studying a guideline with histological characteristics of DVIN. Kappa statistics were used to compare the interobserver variability. Pathologists with a substantial agreement were asked to rank items by usefulness in the recognition of DVIN. The interobserver agreement during the first session varied between 0.08 and 0.54, which slightly increased during the second session toward an agreement between -0.01 and 0.75. Pathologists specialized in gynecopathology reached a substantial agreement (kappa 0.75). The top five of criteria indicated to be the most useful in the diagnosis of DVIN included: atypical mitosis in the basal layer, basal cellular atypia, dyskeratosis, prominent nucleoli and elongation and anastomosis of rete ridges. In conclusion, the histopathological diagnosis of DVIN is difficult, which is expressed by low interobserver agreement. Only in experienced pathologists with training in gynecopathology, kappa values reached a substantial agreement after providing strict guidelines. Therefore, it should be considered that specimens with an unclear diagnosis and/or clinical suspicion for DVIN should be revised by a pathologist specialized in gynecopathology. When adhering to suggested criteria the diagnosis of DVIN can be made easier.Modern Pathology advance online publication, 1 February 2013; doi:10.1038/modpathol.2012.235.
    Modern Pathology 02/2013; DOI:10.1038/modpathol.2012.235 · 6.36 Impact Factor
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    ABSTRACT: Many attempts have been made to combine the high diagnostic accuracy and conclusive rate of core needle biopsy (CNB) with the speed of fine needle aspiration cytology in evaluation of solid breast lesions. Multiple hybrid techniques have been developed to achieve this. We describe a cohort of patients for whom we used a relatively new, accelerated method of CNB processing, allowing for a definitive diagnosis the same day. All patients visiting the Radboud University Nijmegen Medical Centre breast clinic during a 4-year period were reviewed to identify all CNBs in this period performed in a same-day diagnosis track. CNB result was compared to post-operative pathology reports when available, and to follow-up when patients were not surgically treated. 1,060 patients underwent CNB of 1,383 lesions, 898 of which in a same-day diagnosis track with a sensitivity of 96.9 % and a specificity of 99.4 %. The inconclusive rate was 9.2 %. For a same-day diagnosis for solid breast lesions, we could give a conclusive diagnosis with accelerated CNB processing in 65 % of our patients requiring CNB. This technique can be used reliably in a same-day diagnosis breast clinic with a very high sensitivity, specificity, and conclusive rate.
    Breast Cancer Research and Treatment 12/2012; DOI:10.1007/s10549-012-2372-2 · 4.20 Impact Factor
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    ABSTRACT: BACKGROUND: NOTCH signaling is involved in every step of metazoan development and maintenance of adult tissue homeostasis. It is frequently deregulated by mutations and overexpression in different cancer types including solid tumors such as breast cancer. Another common feature of solid tumors is hypoxia, which occurs due to defective or insufficient vascularization. Hypoxia-inducible factors (HIFs) are key regulators of the homeostatic response to low oxygen levels. HIF-1α is overexpressed in many solid tumors, including breast cancer. Hypoxia-induced stabilization of HIF transcription factors has been shown to lead to NOTCH activation in vitro in different contexts and tissues, causing differentiation arrest and induction of proliferation and migration. METHODS: Since the link between HIF-1α and NOTCH signalling has hardly been studied, we set out to closely investigate associations between the expression of HIF-1α and NOTCH pathway members in primary and metastatic human breast cancer specimens and their prognostic value. RESULTS: Co-expression of NOTCH1 intracellular domain (N1ICD) and HIF-1α was associated with a high grade and a high proliferation rate in invasive breast cancer. HIF-1α expression was low in classic, but high in pleomorphic lobular cancers, which also frequently showed stromal HIF-1α expression. NOTCH1 pathway activation was prognostically unfavorable. CONCLUSION: In breast cancer, NOTCH pathway activation appears to be associated with a poor prognosis, but NOTCH and HIF signaling do not seem to be functionally associated.
    09/2012; 35(6). DOI:10.1007/s13402-012-0102-8
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    ABSTRACT: Poly(ADP-ribose) polymerase 1 (PARP) is a key element of the single-base excision pathway for repair of DNA single-strand breaks. To compare the cytoplasmic and nuclear poly(ADP-ribose) expression between familial (BRCA1, BRCA2, or non BRCA1/2) and sporadic breast cancer, we investigated 39 sporadic and 39 familial breast cancer cases. The two groups were matched for hormone receptor status and human epidermal growth factor receptor 2 status. Additionally, they were matched by grading with a maximum difference of ±1 degree (e.g., G2 instead of G3). Cytoplasmic PARP (cPARP) expression was significantly higher in familial compared to sporadic breast cancer (P = 0.008, chi-squared test for trends) and a high nuclear PARP expression (nPARP) was significantly more frequently observed in familial breast cancer (64 %) compared with sporadic breast cancer (36 %) (P = 0.005, chi-squared test). The overall PARP expression was significantly higher in familial breast cancer (P = 0.042, chi-squared test). In familial breast cancer, a combination of high cPARP and high nPARP expression is the most common (33 %), whereas in sporadic breast cancer, a combination of low cPARP and intermediate nPARP expression is the most common (39 %). Our results show that the overall PARP expression in familial breast cancer is higher than in sporadic breast cancer which might suggest they might respond better to treatment with PARP inhibitors.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 09/2012; 461(4):425-31. DOI:10.1007/s00428-012-1311-2 · 2.56 Impact Factor
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    ABSTRACT: TRPM7 encodes a Ca2+-permeable nonselective cation channel with kinase activity. TRPM7 has been implicated in control of cell adhesion and migration, but whether TRPM7 activity contributes to cancer progression has not been established. Here we report that high levels of TRPM7 expression independently predict poor outcome in breast cancer patients and that it is functionally required for metastasis formation in a mouse xenograft model of human breast cancer. Mechanistic investigation revealed that TRPM7 regulated myosin II-based cellular tension, thereby modifying focal adhesion number, cell-cell adhesion and polarized cell movement. Our findings therefore suggest that TRPM7 is part of a mechanosensory complex adopted by cancer cells to drive metastasis formation.
    Cancer Research 08/2012; 72(16):4250-61. DOI:10.1158/0008-5472.CAN-11-3863 · 9.28 Impact Factor
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    ABSTRACT: Mammographic population screening in The Netherlands has increased the number of breast cancer patients with small and non-palpable breast tumors. Nevertheless, mammography is not ultimately sensitive and specific for distinct subtypes. Molecular imaging with targeted tracers might increase specificity and sensitivity of detection. Because development of new tracers is labor-intensive and costly, we searched for the smallest panel of tumor membrane markers that would allow detection of the wide spectrum of invasive breast cancers. Tissue microarrays containing 483 invasive breast cancers were stained by immunohistochemistry for a selected set of membrane proteins known to be expressed in breast cancer. The combination of highly tumor-specific markers glucose transporter 1 (GLUT1), epidermal growth factor receptor (EGFR), insulin-like growth factor-1 receptor (IGF1-R), human epidermal growth factor receptor 2 (HER2), hepatocyte growth factor receptor (MET), and carbonic anhydrase 9 (CAIX) 'detected' 45.5% of tumors, especially basal/triple negative and HER2-driven ductal cancers. Addition of markers with a 2-fold tumor-to-normal ratio increased the detection rate to 98%. Including only markers with >3 fold tumor-to-normal ratio (CD44v6) resulted in an 80% detection rate. The detection rate of the panel containing both tumor-specific and less tumor-specific markers was not dependent on age, tumor grade, tumor size, or lymph node status. In search of the minimal panel of targeted probes needed for the highest possible detection rate, we showed that 80% of all breast cancers express at least one of a panel of membrane markers (CD44v6, GLUT1, EGFR, HER2, and IGF1-R) that may therefore be suitable for molecular imaging strategies. This study thereby serves as a starting point for further development of a set of antibody-based optical tracers with a high breast cancer detection rate.
    BMC Cancer 06/2012; 12:240. DOI:10.1186/1471-2407-12-240 · 3.32 Impact Factor
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    ABSTRACT: Background In the MIRROR study, pN0(i + ) and pN1mi were associated with reduced 5-year disease-free survival (DFS) compared with pN0. Nodal status (N-status) was assessed after central pathology review and restaging according to the sixth AJCC classification. We addressed the impact of pathology review. Patients and methods Early favorable primary breast cancer patients, classified pN0, pN0(i + ), or pN1(mi) by local pathologists after sentinel node procedure, were included. We assessed the impact of pathology review on N-status (n = 2842) and 5-year DFS for those without adjuvant therapy (n = 1712). Results In all, 22% of the 1082 original pN0 patients was upstaged. Of the 623 original pN0(i + ) patients, 1% was downstaged, 26% was upstaged. Of 1137 patients staged pN1mi, 15% was downstaged, 11% upstaged. Originally, 5-year DFS was 85% for pN0, 74% for pN0(i + ), and 73% for pN1mi; HR 1.70 [95% confidence interval (CI) 1.27-2.27] and HR 1.57 (95% CI 1.16-2.13), respectively, compared with pN0. By review staging, 5-year DFS was 86% for pN0, 77% for pN0(i + ), 77% for pN1mi, and 74% for pN1 + . Conclusion Pathology review changed the N-classification in 24%, mainly upstaging, with potentially clinical relevance for individual patients. The association of isolated tumor cells and micrometastases with outcome remained unchanged. Quality control should include nodal breast cancer staging.
    Annals of Oncology 04/2012; 23(10):2561-6. DOI:10.1093/annonc/mds072 · 6.58 Impact Factor
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    ABSTRACT: Background The cost-effectiveness of adjuvant systemic therapy in patients with low-risk breast cancer and nodal isolated tumor cells or micrometastases is unknown. Patients and methods A cost-effectiveness analysis of adjuvant systemic therapy was carried out using the costs per 1% event prevented after 5 years of follow-up as incremental cost-effectiveness ratio (ICER). Secondary objective was to establish when adjuvant systemic therapy becomes cost saving. Patients included in the MIRROR study with isolated tumor cells or micrometastases who had a complete 5-year follow-up and who either did or did not receive systemic therapy were eligible. Sensitivity analyses were carried out. Results In the no adjuvant therapy cohort (N = 366), 24.9% of patients had an event within 5 years versus 16.8% of patients in the adjuvant therapy cohort (N = 483) (P < 0.01). The ICER was €363 per 1% event prevented. Beyond 18 years after diagnosis, the extrapolated mean cumulative costs per patient in the no adjuvant therapy cohort exceeded those of the adjuvant therapy cohort. Conclusions In this population of breast cancer patients with isolated tumor cells or micrometastases, €36 300 had to be invested to prevent one event in 5 years of follow-up. Adjuvant systemic therapy was cost saving beyond 18 years after diagnosis.
    Annals of Oncology 03/2012; 23(10):2585-91. DOI:10.1093/annonc/mds051 · 6.58 Impact Factor
  • Cancer Research 02/2012; 71(24 Supplement):PD02-07-PD02-07. DOI:10.1158/0008-5472.SABCS11-PD02-07 · 9.28 Impact Factor
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    ABSTRACT: p53 is a tumor suppressor that is frequently mutated in human cancers. Although alterations in p53 are common in breast cancer, few studies have specifically investigated TP53 mutations in the breast cancer subtype invasive lobular carcinoma (ILC). Recently reported conditional mouse models have indicated that functional p53 inactivation may play a role in ILC development and progression. Since reports on the detection of TP53 mutations in the relatively favorable classic and more aggressive pleomorphic variants of ILC (PILC) are rare and ambiguous, we performed a comprehensive analysis to determine the mutation status of TP53 in these breast cancer subtypes. To increase our understanding of p53-mediated pathways and the roles they may play in the etiology of classic ILC and PILC, we investigated TP53 mutations and p53 accumulation in a cohort of 22 cases of classic and 19 cases of PILC by direct DNA sequencing and immunohistochemistry. We observed 11 potentially pathogenic TP53 mutations, of which three were detected in classic ILC (13.6%) and 8 in PILC (42.1%; p = 0.04). While p53 protein accumulation was not significantly different between classic and pleomorphic ILC, mutations that affected structure and protein function were significantly associated with p53 protein levels. TP53 mutations occur more frequently in PILC than classic ILC.
    02/2012; 35(2):111-8. DOI:10.1007/s13402-012-0071-y

Publication Stats

1k Citations
364.14 Total Impact Points


  • 1999–2015
    • Radboud University Medical Centre (Radboudumc)
      • Department of Human Genetics
      Nymegen, Gelderland, Netherlands
  • 2000–2013
    • Radboud University Nijmegen
      • • Department of Pathology
      • • Department of Surgery
      Nymegen, Gelderland, Netherlands
  • 2009–2012
    • Maastricht Universitair Medisch Centrum
      • Central Diagnostic Laboratory
      Maestricht, Limburg, Netherlands
  • 2008
    • University Medical Center Utrecht
      • Department of Pathology
      Utrecht, Provincie Utrecht, Netherlands
  • 2006
    • Rijnstate Hospital
      Arnheim, Gelderland, Netherlands
  • 2003
    • IJsselland Ziekenhuis
      Kapelle, South Holland, Netherlands