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Dive into the research topics where Lieuwe J. Melchers is active.

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Featured researches published by Lieuwe J. Melchers.


International Journal of Oral and Maxillofacial Surgery | 2009

Exercise adherence in patients with trismus due to head and neck oncology: a qualitative study into the use of the Therabite.

Lieuwe J. Melchers; E. van Weert; Carien H. G. Beurskens; Harmannus Reintsema; A. P. Slagter; Jan Roodenburg; Pieter U. Dijkstra

Trismus is a common problem after treatment of head and neck cancer. The Therabite is an effective treatment for trismus. To explore the factors that may influence Therabite exercise adherence, how these interrelate and to provide aims for interventions to increase adherence, the authors conducted a multi-centre, formal-evaluative qualitative retrospective study. 21 patients treated for head-neck cancer were interviewed in semi-structured, in-depth interviews. Internal motivation to exercise, the perceived effect, self-discipline and having a clear exercise goal influenced Therabite exercise adherence positively. Perceiving no effect, limitation in Therabite opening range and reaching the exercise goal or a plateau in mouth opening were negative influences. Pain, anxiety and the physiotherapist could influence adherence both positively and negatively. Based on the results, a model for Therabite exercise adherence was proposed. It is important to signal and assess the factors negatively influencing Therabite adherence, specifically before there is a perceived effect. Research is needed to examine why some patients do not achieve results despite high exercise adherence, to identify effective exercise regimens and to assess proposed interventions aimed to increase Therabite exercise adherence.


Oral Oncology | 2012

Tumour infiltration depth >= 4 mm is an indication for an elective neck dissection in pT1cN0 oral squamous cell carcinoma

Lieuwe J. Melchers; Ed Schuuring; B.A.C. van Dijk; de Truuske Bock; Max J. H. Witjes; van der Bernard Laan; J.E. van der Wal; Jan Roodenburg

Patients with pT1cN0 oral squamous cell carcinomas (OSCC) are generally not treated with a neck dissection (ND). However, in 25% of cN0 patients, nodal metastases become apparent during follow-up. Infiltration depth of the primary tumour has been consistently associated with the presence of nodal metastasis, but proposed cut-off depths for performing a ND vary considerably. The aim of this study was to explore the infiltration depth as predictor for the nodal status and to recommend a cut-off depth for performing a ND. From our database of 351 primary oral carcinomas, we selected all pT1-2 tumours (n=246). Infiltration depth was measured in 212 cases. Neck status was determined by histopathological examination of the dissection specimen, or by at least two years of follow-up. Mean infiltration depth was 5.49 mm (95% CI: 4.86-6.12) in the N0 and 8.40 mm (95% CI: 7.38-9.43) in the N+ group (p<0.001). cN status, lymphovascular invasion and infiltration depth were the only independent predictors for nodal status in multiple logistic regression. ROC-analysis on pT1cN0 tumours resulted in an optimal cut-off for the prediction of the nodal status at a depth of 4.59 mm. This cut-off identified a subgroup of patients at increased risk for nodal metastasis (OR=8.3) and with significantly shorter survival. Tumour infiltration depth is an independent predictor for nodal status in pT1-2 OSCC. In pT1cN0 tumours, a cut-off at 4.59 mm results in the best predictive value. We recommend an infiltration depth of ≥4 mm as an indication to perform a neck dissection in pT1cN0 OSCC.


Oral Oncology | 2013

Lack of claudin-7 is a strong predictor of regional recurrence in oral and oropharyngeal squamous cell carcinoma

Lieuwe J. Melchers; L. Bruine de Bruin; Ulrike Schnell; Lorian Slagter-Menkema; Mirjam F. Mastik; de Truuske Bock; van Boukje Dijk; Ben N. G. Giepmans; van der Bernard Laan; J.E. van der Wal; Jan Roodenburg; Ed Schuuring

OBJECTIVES Adequate treatment of oral and oropharyngeal squamous cell carcinoma (OSCC) is dependent on correctly predicting the presence of lymph node metastases. Current methods to diagnose nodal metastases partly result in overtreatment with associated morbidity and undertreatment with decreased disease-free survival. E-cadherin has been studied extensively as potential marker for lymph node metastases. EpCAM and claudin-7 have a functional relationship with E-cadherin, forming a complex that promotes tumourigenicity in vitro. We hypothesize that the co-expression patterns of these related molecules is a better prognostic marker for nodal status and regional recurrences. MATERIALS AND METHODS We constructed separate tissue microarrays of tumour centre and tumour invasive front of 227 OSCC with complete clinicopathological and follow-up data, including HPV status, and performed immunohistochemistry for these molecules. RESULTS Lack of E-cadherin and presence of cytoplasmic EpCAM expression in the tumour front were predictive for nodal metastasis, but no co-expression pattern was found clinically relevant. Lack of claudin-7 in the tumour centre was highly and independently predictive for shorter regional disease-free survival (HR=0.19; 95%CI: 0.06-0.62) and disease-specific survival (HR=0.43; 95%CI: 0.21-0.87). High-risk HPV was not associated with any marker. CONCLUSIONS The expression of E-cadherin and EpCAM, depending on the specific tumour sublocalization, is predictive for nodal status. However, co-expression did not improve the prediction of nodal status, indicating that the proposed in vitro complex is not functional in clinical samples. Additionally, lack of claudin-7 expression in the tumour centre may be used to identify patients with increased risk for regional recurrence.


Histopathology | 2013

FADD expression is associated with regional and distant metastasis in squamous cell carcinoma of the head and neck

W J Pattje; Lieuwe J. Melchers; Lorian Slagter-Menkema; Mirjam F. Mastik; M L Schrijvers; Johan H. Gibcus; Philippus Kluin; O Hoegen-Chouvalova; van der Bernard Laan; Jan Roodenburg; J.E. van der Wal; Ed Schuuring; Johannes A. Langendijk

The Fas‐associated death domain gene (FADD) is often overexpressed in squamous cell carcinoma of the head and neck (HNSCC), and is considered to be a driver gene in amplification of the chromosomal 11q13.3 region. Amplification of 11q13.3 is associated with increased metastasis in HNSCC and breast cancer. The aim of this study was to investigate the association between FADD protein expression in advanced‐stage HNSCC and clinicopathological features and outcome.


British Journal of Cancer | 2015

Detection of HPV-associated oropharyngeal tumours in a 16-year cohort: more than meets the eye

Lieuwe J. Melchers; Mirjam F. Mastik; B. Samaniego Cameron; van Boukje Dijk; de Truuske Bock; van der Bernard Laan; van der Bert Vegt; Ernst-Jan M. Speel; Jan Roodenburg; Max J. H. Witjes; Ed Schuuring

Background:Accurate assessment of the prevalence of the human papilloma virus (HPV) in oropharyngeal tumours (OpSCC) is important because HPV-positive OpSCC are consistently associated with an improved overall survival. Recently, an algorithm has become available that reliably detects clinically relevant HPV in tumour tissue, however, no complete cohorts have been tested. The aim was to determine the prevalence of active high-risk HPV infection in a complete cohort of OpSCC collected over a 16-year period.Methods:Using a triple algorithm of p16 immunohistochemistry, HPV-BRISH and HPV-PCR, we assessed the prevalence of active HPV infection in all OpSCC diagnosed in our hospital from 1997 to 2012 (n=193) and a random selection of 200 oral tumours (OSCC).Results:Forty-seven OpSCC (24%) were HPVGP PCR-positive; 42 cases were HPV16+, 1 HPV18+, 3 HPV33+ and 1 HPV35+. Brightfield in situ hybridisation did not identify additional HPV-positive cases. Human papilloma virus-associated tumour proportion increased from 13% (1997–2004) to 30% (2005–2012). Human papilloma virus-positivity was an independent predictor for longer disease-specific survival (HR=0.22; 95%CI:0.10–0.47). Only one OSCC was HPV+.Conclusions:In our cohort, the incidence of HPV-associated OpSCC is low but increasing rapidly. The strict detection algorithm, analysis of disease-specific survival and the complete cohort, including palliatively treated patients, may influence the reported prevalence and prognostic value of HPV in OpSCC.


Genes, Chromosomes and Cancer | 2016

Identification and validation of WISP1 as an epigenetic regulator of metastasis in oral squamous cell carcinoma

Martijn J.A.M. Clausen; Lieuwe J. Melchers; Mirjam F. Mastik; Lorian Slagter-Menkema; Harry J.M. Groen; Bernard F. A. M. van der Laan; Wim Van Criekinge; Tim De Meyer; Simon Denil; G. Bea A. Wisman; Jan Roodenburg; Ed Schuuring

Lymph node (LN) metastasis is the most important prognostic factor in oral squamous cell carcinoma (OSCC) patients. However, in approximately one third of OSCC patients nodal metastases remain undetected, and thus are not adequately treated. Therefore, clinical assessment of LN metastasis needs to be improved. The purpose of this study was to identify DNA methylation biomarkers to predict LN metastases in OSCC. Genome wide methylation assessment was performed on six OSCC with (N+) and six without LN metastases (N0). Differentially methylated sequences were selected based on the likelihood of differential methylation and validated using an independent OSCC cohort as well as OSCC from The Cancer Genome Atlas (TCGA). Expression of WISP1 using immunohistochemistry was analyzed on a large OSCC cohort (n = 204). MethylCap‐Seq analysis revealed 268 differentially methylated markers. WISP1 was the highest ranking annotated gene that showed hypomethylation in the N+ group. Bisulfite pyrosequencing confirmed significant hypomethylation within the WISP1 promoter region in N+ OSCC (P = 0.03) and showed an association between WISP1 hypomethylation and high WISP1 expression (P = 0.01). Both these results were confirmed using 148 OSCC retrieved from the TCGA database. In a large OSCC cohort, high WISP1 expression was associated with LN metastasis (P = 0.05), disease‐specific survival (P = 0.022), and regional disease‐free survival (P = 0.027). These data suggest that WISP1 expression is regulated by methylation and WISP1 hypomethylation contributes to LN metastasis in OSCC. WISP1 is a potential biomarker to predict the presence of LN metastases.


Epigenetics | 2015

Identification of methylation markers for the prediction of nodal metastasis in oral and oropharyngeal squamous cell carcinoma

Lieuwe J. Melchers; Martijn J.A.M. Clausen; Mirjam F. Mastik; Lorian Slagter-Menkema; J.E. van der Wal; G. B. A. Wisman; Jan Roodenburg; Ed Schuuring

Hypermethylation is an important mechanism for the dynamic regulation of gene expression, necessary for metastasizing tumour cells. Our aim is to identify methylation tumour markers that have a predictive value for the presence of regional lymph node metastases in patients with oral and oropharyngeal squamous cell carcinoma (OOSCC). Significantly differentially expressed genes were retrieved from four reported microarray expression profiles comparing pN0 and pN+ head-neck tumours, and one expression array identifying functionally hypermethylated genes. Additional metastasis-associated genes were included from the literature. Thus genes were selected that influence the development of nodal metastases and might be regulated by methylation. Methylation-specific PCR (MSP) primers were designed and tested on 8 head-neck squamous cell carcinoma cell lines and technically validated on 10 formalin-fixed paraffin-embedded (FFPE) OOSCC cases. Predictive value was assessed in a clinical series of 70 FFPE OOSCC with pathologically determined nodal status. Five out of 28 methylation markers (OCLN, CDKN2A, MGMT, MLH1 and DAPK1) were frequently differentially methylated in OOSCC. Of these, MGMT methylation was associated with pN0 status (P = 0.02) and with lower immunoexpression (P = 0.02). DAPK1 methylation was associated with pN+ status (P = 0.008) but did not associate with protein expression. In conclusion, out of 28 candidate genes, two (7%) showed a predictive value for the pN status. Both genes, DAPK1 and MGMT, have predictive value for nodal metastasis in a clinical group of OOSCC. Therefore DNA methylation markers are capable of contributing to diagnosis and treatment selection in OOSCC. To efficiently identify additional new methylation markers, genome-wide methods are needed.


Histopathology | 2016

Reproducibility and prognostic value of pattern of invasion scoring in low-stage oral squamous cell carcinoma

Marjolein G. J. Heerema; Lieuwe J. Melchers; Jan Roodenburg; Ed Schuuring; Geertruida H. de Bock; Bert van der Vegt

To evaluate and compare the prognostic value and reproducibility of different methods of pattern of invasion scoring in oral squamous cell carcinomas. The additional prognostic value to established histopathological prognostic factors was also analysed.


International Journal of Radiation Oncology Biology Physics | 2014

Head and Neck Squamous Cell Carcinomas Do Not Express EGFRvIII

Lieuwe J. Melchers; Martijn J.A.M. Clausen; Mirjam F. Mastik; Lorian Slagter-Menkema; Johannes A. Langendijk; Bernard F. A. M. van der Laan; Jacqueline E. van der Wal; Bert van der Vegt; Jan Roodenburg; Ed Schuuring

PURPOSE To assess the prevalence of EGFRvIII, a specific variant of EGFR (epidermal growth factor receptor), in 3 well-defined cohorts of head and neck squamous cell carcinoma (HNSCC). METHODS AND MATERIALS Immunohistochemistry for the specific detection of EGFRvIII using the L8A4 antibody was optimized on formalin-fixed, paraffin-embedded tissue using glioblastoma tissue. It was compared with EGFR and EGFRvIII RNA expression using a specific reverse transcription-polymerase chain reaction also optimized for formalin-fixed, paraffin-embedded tissue. Tissue microarrays including 531 HNSCCs of various stages with complete clinicopathologic and follow-up data were tested for the presence of EGFRvIII. RESULTS None of the 531 cases showed EGFRvIII protein expression. Using an immunohistochemistry protocol reported by others revealed cytoplasmic staining in 8% of cases. Reverse transcription-polymerase chain reaction for the EGFRvIII transcript of the 28 highest cytoplasmic staining cases, as well as 69 negative cases, did not show expression in any of the tested cases, suggesting aspecific staining by a nonoptimal protocol. CONCLUSIONS The EGFRvIII mutation is not present in HNSCC. Therefore, EGFRvIII does not influence treatment response in HNSCC and is not a usable clinical prognostic marker.


Epigenetics | 2016

RAB25 expression is epigenetically downregulated in oral and oropharyngeal squamous cell carcinoma with lymph node metastasis

Martijn J.A.M. Clausen; Lieuwe J. Melchers; Mirjam F. Mastik; Lorian Slagter-Menkema; Harry J.M. Groen; B.F.A.M. van der Laan; W. van Criekinge; T. De Meyer; Simon Denil; B. van der Vegt; G. B. A. Wisman; Jan Roodenburg; Ed Schuuring

ABSTRACT Oral and oropharyngeal squamous cell carcinoma (OOSCC) have a low survival rate, mainly due to metastasis to the regional lymph nodes. For optimal treatment of these metastases, a neck dissection is required; however, inaccurate detection methods results in under- and over-treatment. New DNA prognostic methylation biomarkers might improve lymph node metastases detection. To identify epigenetically regulated genes associated with lymph node metastases, genome-wide methylation analysis was performed on 6 OOSCC with (pN+) and 6 OOSCC without (pN0) lymph node metastases and combined with a gene expression signature predictive for pN+ status in OOSCC. Selected genes were validated using an independent OOSCC cohort by immunohistochemistry and pyrosequencing, and on data retrieved from The Cancer Genome Atlas. A two-step statistical selection of differentially methylated sequences revealed 14 genes with increased methylation status and mRNA downregulation in pN+ OOSCC. RAB25, a known tumor suppressor gene, was the highest-ranking gene in the discovery set. In the validation sets, both RAB25 mRNA (P = 0.015) and protein levels (P = 0.012) were lower in pN+ OOSCC. RAB25 mRNA levels were negatively correlated with RAB25 methylation levels (P < 0.001) but RAB25 protein expression was not. Our data revealed that promoter methylation is a mechanism resulting in downregulation of RAB25 expression in pN+ OOSCC and decreased expression is associated with lymph node metastasis. Detection of RAB25 methylation might contribute to lymph node metastasis diagnosis and serve as a potential new therapeutic target in OOSCC.

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Jan Roodenburg

University Medical Center Groningen

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Ed Schuuring

University Medical Center Groningen

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Mirjam F. Mastik

University Medical Center Groningen

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Lorian Slagter-Menkema

University Medical Center Groningen

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Martijn J.A.M. Clausen

University Medical Center Groningen

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Bert van der Vegt

University Medical Center Groningen

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Harry J.M. Groen

University Medical Center Groningen

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J.E. van der Wal

University Medical Center Groningen

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Max J. H. Witjes

University Medical Center Groningen

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