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Dive into the research topics where M.L.F. van Velthuysen is active.

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Featured researches published by M.L.F. van Velthuysen.


British Journal of Surgery | 2010

Systematic review of the benefits and risks of neoadjuvant chemoradiation for oesophageal cancer

E.F.W. Courrech Staal; Berthe M.P. Aleman; Henk Boot; M.L.F. van Velthuysen; H. van Tinteren; J.W. van Sandick

Surgery alone for locally advanced oesophageal cancer is associated with low cure rates. The benefits and risks of neoadjuvant chemoradiation for patients with oesophageal cancer were evaluated.


Clinical Cancer Research | 2009

PIK3CA mutations predict local recurrences in rectal cancer patients.

Yudong He; L. J. Van't Veer; I. Mikolajewska-Hanclich; M.L.F. van Velthuysen; Eliane C.M. Zeestraten; Iris D. Nagtegaal; C.J.H. van de Velde; Corrie A.M. Marijnen

Purpose: Identifying rectal cancer patients at risk for local recurrence would allow for refinement in the selection of patients who would benefit from preoperative radiotherapy. PIK3CA, KRAS, and BRAF mutations are commonly found in colon cancers, but their prevalence has not been clearly assessed in rectal cancer. In this study, we aim to determine the mutation frequencies of PIK3CA, KRAS, and BRAF and to investigate whether a mutation may be used as a prognostic parameter in rectal cancer patients. Experimental Design: We evaluated DNA mutations in PIK3CA, KRAS, and BRAF in 240 stage I to III rectal tumors obtained from nonirradiated patients from the Dutch Total Mesorectal Excision trial. Results:PIK3CA, KRAS, and BRAF mutations were identified in 19 (7.9), 81 (33.9), and 5 (2.1) rectal cancers. Patients with PIK3CA mutations developed more local recurrences (5-year risks, 27.8 versus 9.4; P = 0.006) and tended to develop these recurrences more rapidly after surgery (median local recurrence-free interval since surgery: 7.9 versus 19.6 months; P = 0.07) than patients without PIK3CA mutations. In multivariate analysis, PIK3CA mutations remained as an independent predictor for the development of local recurrences (hazard ratio, 3.4; 95 confidence interval, 1.2-9.2; P = 0.017), next to tumor-node-metastasis stage. Conclusion:PIK3CA mutations can be used as a biomarker in identifying rectal cancer patients with an increased risk for local recurrences. Currently, our findings suggest that prospective evaluation of PIK3CA mutation status could reduce overtreatment by preoperative radiotherapy for the low-risk patients who might otherwise only experience the side effects. (Clin Cancer Res 2009;15(22):695662)


Clinical Microbiology Reviews | 2000

Glomerulopathy Associated with Parasitic Infections

M.L.F. van Velthuysen; Sandrine Florquin

Although parasitic infections do not usually present with disturbance in renal function, glomerular lesions can be seen in most of these infections. The glomerular lesions observed in parasitic infections cover the whole range of glomerular lesions known, but most of them are proliferative. Little is known of the exact pathogenic mechanisms. In this review, we try to explain the glomerular lesions associated with parasitic infections in terms of the specific immunologic events observed during these diseases against the background of recent developments in the general knowledge of the pathogenesis of glomerular disease.


Virchows Archiv | 2003

Report of an Amsterdam working group on Barrett esophagus.

G J A Offerhaus; P Correa; S. van Eeden; Karel Geboes; Paul Drillenburg; Michael Vieth; M.L.F. van Velthuysen; Hisashi Watanabe; Pentti Sipponen; F. J. W. Ten Kate; Fredrik T. Bosman; A Bosma; Ari Ristimäki; H. van Dekken; Robert H. Riddell; G N J Tytgat

More than 50 years have passed since Barrett described a case of peptic ulcer disease of the esophagus and the condition that would carry his name [1]. It is now generally accepted that Barrett esophagus is the result of long-standing gastroesophageal reflux disease leading to replacement of the normal stratified squamous epithelial lining of the esophagus by glandular epithelium of various types [24, 32]. The importance of a diagnosis of Barrett esophagus is its association with the development of an esophageal adenocarcinoma. In contrast to what Norman Barrett originally thought, Barrett esophagus is a premalignant condition, and the incidence of Barrett carcinoma has increased dramatically since his publication in 1950 [12]. Barrett adenocarcinoma is preceded by a well-defined premalignant lesion, i.e., dysplasia (intraepithelial neoG. J. A. Offerhaus · S. van Eeden · F. J. W. ten Kate · A. Bosma Department of Pathology, Academic Medical Center Amsterdam, The Netherlands


International Journal of Cancer | 2012

Human papillomavirus status in young patients with head and neck squamous cell carcinoma

H.S. van Monsjou; M.L.F. van Velthuysen; M.W.M. van den Brekel; Ekaterina S. Jordanova; Cornelis J. M. Melief; A. J. M. Balm

The role of human papillomavirus (HPV) in head and neck squamous cell carcinoma (HNSCC) development has been recognized only in the last decade. Although younger patients develop HNSCC associated with HPV, the incidence in young patients has not been studied. Forty‐five young HNSCC patients (<40 years) were tested for HPV and the expression of p16ink4a and p53 in tumor biopsies. The presence of HPV was correlated with the absence and presence of alcohol and tobacco exposure. Paraffin‐embedded, archival biopsy materials from HNSCC of 45 patients younger than 40 years were analyzed. HPV subtypes were identified by PCR followed by genotyping. Expression of p16ink4a and p53 were determined by immunohistochemistry. Fourteen (31%) of the HNSCC specimens from 45 patients unequivocally exhibited HPV16 positivity. Sixty percentage of the oropharyngeal tumors and 5% of the oral cavity tumors were HPV16 positive. P16ink4a overexpression was detected in 93% of the HPV16‐positive tumors. None of the HPV16 tumors showed p53 overexpression. There was no association of HPV positivity with (lack of) exposure to alcohol and smoking. HPV association was not exclusively detected in nonsmoking, nondrinking young HNSCC patients. The presence of p16ink4a accumulation and the absence of p53 overexpression are good surrogate markers for HPV‐associated HNSCC.


Oral Oncology | 2014

The influence of nodal yield in neck dissections on lymph node ratio in head and neck cancer

C.C.M. Marres; M. de Ridder; I. Hegger; M.L.F. van Velthuysen; Michael Hauptmann; Arash Navran; Alfons J. M. Balm

OBJECTIVES Recent studies suggest that lymph node ratio (LNR) is a strong prognostic factor in head and neck cancer. This study aims to determine if the yield of harvested lymph nodes (LNs) influences the LNR. METHODS The study included 522 head and neck cancer patients, undergoing 638 primary and salvage (selective) neck dissections between 2002 and 2012. Before 2007 the neck dissection specimens were macroscopically and microscopically examined by pathologists and after 2007 the macroscopic examination was performed by pathology technicians. For comparison of mean LN yields, univariate and multivariate analyses were performed. RESULTS The mean number of LNs among 374 specimens examined by pathologists was 24 (range 0-89) vs. 32 (range 2-89) among 264 specimens examined by pathology technicians (P<.001). This caused the mean LNR in the non pre-treated patient group to drop from 11.4% to 8.7%. The counts of LNs per type of neck dissection were significantly different and increased with the number of levels involved. However, there was no linear relationship and the higher yields could be mostly ascribed to LNs in level V. The LNR varied from 8.1% to 18.4% among the different types of neck dissections. CONCLUSIONS A significant increase in the number of harvested LNs, but a decrease in LNR was observed after introducing pathology technicians for macroscopic examination. A clear association between the extent of the dissection and the number of harvested LNs was observed. LNR appears to be strongly dependent on the harvesting protocol and the extent of the dissection.


Clinical Cancer Research | 2009

Differential diagnosis of pulmonary carcinoma following head and neck cancer by genetic analysis.

T.W. Geurts; M.L.F. van Velthuysen; F. Broekman; T. Hooft van Huysduynen; M.W.M. van den Brekel; N. van Zandwijk; H. van Tinteren; Petra M. Nederlof; A. J. M. Balm; Ruud H. Brakenhoff

Purpose: Patients with head and neck cancer often develop a lung tumor that can be diagnosed as distant metastasis (DM) or second primary tumor (SPT). In this study, we use TP53 mutation analysis for validation of an allelic loss marker panel and a decision algorithm for distinguishing between DM and SPT. Experimental Design: Tumor pairs of 39 patients were analyzed for TP53 mutations, for patterns of allelic loss and immunohistochemical analysis of p53 expression. Results of these three analyses were compared, using mutation analysis as gold standard. Results: Loss of heterozygosity (LOH) analysis indicated DM in 15 and SPT in 23 cases (one inconclusive). TP53 mutation analysis was informative in 15 cases. Based on the p53 mutation status alone, nine tumors were diagnosed as SPT and six as DM. In all 15 cases the LOH analysis was in concordance with the TP53 mutation analysis. Immunostaining for p53 showed promise as a first scan to diagnose lung tumors as SPT but cannot be used to diagnose DM. Conclusion: The TP53 mutation data validate the suitability of the LOH marker panel and decision algorithm for differential diagnosis of DM and SPT in the lung. LOH analysis can theoretically be exploited in almost all cases and is less laborious than TP53 mutation analysis.


International Journal of Surgical Oncology | 2010

Diagnosis and treatment of a neck node swelling suspicious for a malignancy: an algorithmic approach.

A.J.M. Balm; M.L.F. van Velthuysen; F. Hoebers; Wouter V. Vogel; M.W.M. van den Brekel

Aim. To present an up-to-date algorithm incorporating recent advances regarding its diagnosis and treatment. Method. A Medline/Pubmed search was performed to identify relevant studies published in English from 1990 until 2008. Only clinical studies were identified and were used as basis for the diagnostic algorithm. Results. The eligible literature provided only observational evidence. The vast majority of neck nodes from occult primaries (>90%) represent SCC with a high incidence among middle aged man. Smoking and alcohol abuse are important risk factors. Asiatic and North African patients with neck node metastases are at risk of harbouring an occult nasopharyngeal carcinoma. The remainder are adenocarcinoma, undifferentiated carcinoma, melanoma, thyroid carcinoma and Merkel cell carcinoma. Fine needle aspiration cytology (FNAC) reaches sensitivity and specificity percentages of 81% and 100%, respectively and plays an important role as the second diagnostic step after routine ENT mirror and/or endoscopic examination. FDG-PET/CT has proven to be helpful in identifying occult primary carcinomas of the head and neck, especially when applied as a guiding tool prior to panendoscopy, and may induce treatment related clinical decisions in up to 60% of cases. Conclusion. Although reports on the diagnostic process offer mainly descriptive studies, current information seems sufficient to formulate a diagnostic algorithm to contribute to a more systematic diagnostic approach preventing unnecessary steps.


Journal of Endocrinological Investigation | 2010

Expression and ligand binding of bombesin receptors in pulmonary and intestinal carcinoids

P. Kuiper; Hein W. Verspaget; I. Biemond; E. S. de Jonge-Muller; S. van Eeden; M.L.F. van Velthuysen; Babs G. Taal; C. B. H. W. Lamers

Introduction: Carcinoids are mainly found in the gastrointestinal (65%) and bronchopulmonary tract (25%). These neuroendocrine tumors secrete a wide range of bioactive peptides, including gastrin releasing peptide and neuromedin B, the mammalian analogs of bombesin. The purpose of this study was to investigate the quantity and localization of bombesin receptors in gastrointestinal and pulmonary carcinoids, and to reveal whether bombesin-like peptides (BLP) and their receptors are of any value in distinguishing pulmonary carcinoids from carcinoids of intestinal origin. Methods: Carcinoid tumors with pulmonary (no.=9) or intestinal (no.=15) localizations were analyzed by immunohistochemistry, autoradiography, and radioimmunoassay, to examine the presence of bombesin receptor subtypes and determine BLP levels in these tumors. Results: All 3 bombesin receptor subtypes (GRPR, NM-BR, and BRS-3) were present on pulmonary and intestinal carcinoids by immunohistochemistry. In pulmonary carcinoids, low receptor ligand binding densities together with high and low BLP levels were found. Intestinal carcinoids showed predominantly high receptor ligand binding densities in combination with low BLP levels. Conclusions: The expression of bombesin receptor subtypes is independent from the carcinoid tumor origin, and is therefore not recommended as a distinction marker, although carcinoids of pulmonary and intestinal origin possess different receptor binding affinities for bombesin and dissimilar BLP levels. The combined presence of bombesin and its receptors might suggest the presence of a paracrine or autocrine growth loop in carcinoids.


Lasers in Surgery and Medicine | 2015

Differentiation of healthy and malignant tissue in colon cancer patients using optical spectroscopy: A tool for image-guided surgery

G.C. Langhout; Jarich W. Spliethoff; S.J. Schmitz; Arend G. J. Aalbers; M.L.F. van Velthuysen; Theo J.M. Ruers; Koert Kuhlmann

Surgery for colorectal cancer aims for complete tumor resection. Optical‐based techniques can identify tumor and surrounding tissue through the tissue specific optical properties, absorption and scattering, which are both influenced by the biochemical and morphological composition of the tissue.

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Alfons J. M. Balm

Netherlands Cancer Institute

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Corrie A.M. Marijnen

Leiden University Medical Center

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Theo J.M. Ruers

Netherlands Cancer Institute

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A. J. M. Balm

Netherlands Cancer Institute

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H. van Tinteren

Netherlands Cancer Institute

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Henk Boot

Netherlands Cancer Institute

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V.J. Verwaal

Netherlands Cancer Institute

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Wouter V. Vogel

Netherlands Cancer Institute

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Yudong He

Netherlands Cancer Institute

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