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Dive into the research topics where C.R. Leemans is active.

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Featured researches published by C.R. Leemans.


Journal of Clinical Oncology | 2004

The Additional Value of Chemotherapy to Radiotherapy in Locally Advanced Nasopharyngeal Carcinoma: A Meta-Analysis of the Published Literature

Johannes A. Langendijk; C.R. Leemans; Jan Buter; J Berkhof; B.J. Slotman

PURPOSE The purpose of this meta-analysis was to determine the additional value of neoadjuvant, concurrent, and/or adjuvant chemotherapy to radiation in the treatment of locally advanced nasopharyngeal carcinoma (NPC) with regard to the overall survival (OS) and the incidence of local-regional recurrences (LRR) and distant metastases (DM). PATIENTS AND METHODS To be eligible, full published studies had to deal with biopsy-proven NPC and have patients randomly assigned to receive conventional radiotherapy (66 to 70 Gy in 7 weeks) or radiotherapy combined with chemotherapy. RESULTS Ten randomized clinical studies were identified, including 2,450 patients. The pooled hazard ratio (HR) of death for all studies was 0.82 (95% CI, 0.71 to 0.95; P = .01) corresponding to an absolute survival benefit of 4% after 5 years. Three categories of trials were defined according to the sequence of chemotherapy, including neoadjuvant chemotherapy, at least concomitant chemoradiotherapy, and adjuvant chemotherapy. A significant interaction term (P = .02) was found among these three categories. The largest effect was found for concomitant chemotherapy, with a pooled HR of 0.48 (95% CI, 0.32 to 0.72), which corresponds to a survival benefit of 20% after 5 years. Comparable results were found for the incidence of LRR and DM. CONCLUSION The results of this study indicate that concomitant chemotherapy in addition to radiation is probably the most effective way to improve OS in NPC.


Annals of Oncology | 2013

Human papillomavirus detection and comorbidity: critical issues in selection of patients with oropharyngeal cancer for treatment De-escalation trials

M. M. Rietbergen; Ruud H. Brakenhoff; E. Bloemena; B. I. Witte; P. J. F. Snijders; Daniëlle A.M. Heideman; D. Boon; S. Koljenovic; R. J. Baatenburg-de Jong; C.R. Leemans

BACKGROUND The presence of human papillomavirus (HPV)-infection in oropharyngeal squamous cell carcinoma (OPSCC) is a major determinant in prognostic risk modeling. However, most risk models are based on clinical trials which only include a selected patient population. The clinical significance of HPV and other prognostic factors in patients with OPSCC remains to be evaluated in a large, unselected cohort, which also includes patients with stage I/II disease and patients with severe comorbidity. PATIENTS AND METHODS All patients diagnosed with OPSCC in 2000-2006 in two Dutch university hospitals were included. The presence of an oncogenic HPV infection was determined by p16-immunostaining, followed by a high-risk HPV general primer 5+/6+ DNA PCR on the p16-positive cases. Cox regression analysis was carried out to compare survival rates between HPV-positive and HPV-negative patients and a prognostic model was generated by recursive partitioning. RESULTS In total, 163 of 841 (19.4%) tumors were HPV-positive. Patients with HPV-positive OPSCC had a more favorable overall survival [73.5% versus 40.9% after 5 years; P < 0.001; hazard ratio = 0.34, 95% confidence interval (CI) 0.25-0.48] compared with patients with HPV-negative OPSCC. Patients with p16-positive but HPV DNA-negative tumors showed a significantly less favorable survival than patients with p16-positive and HPV DNA-positive tumors (P < 0.001). A prognostic model was developed in which patients were classified into three risk groups according to HPV status, nodal stage and comorbidity. [Harrells concordance index of 0.68 (95% CI 0.65-0.71)]. CONCLUSIONS Tumor HPV status is a strong and independent prognostic factor for survival among patients with OPSCC. A prognostic risk model was proposed, based on our large, unselected cohort of patients with HPV status, comorbidity and nodal stage being the important prognostic factors. In addition, this study emphasizes the importance of performing an HPV DNA-specific test besides p16-immunostaining.


Nutrition and Cancer | 2013

More than 10% weight loss in head and neck cancer patients during radiotherapy is independently associated with deterioration in quality of life.

J.A.E. Langius; A.M. van Dijk; P.A.H. Doornaert; H.M. Kruizenga; J.A. Langendijk; C.R. Leemans; P.J.M. Weijs; I.M. de Leeuw

The authors prospectively assessed the independent association between weight loss and deterioration in quality of life (QOL) in patients treated by radiotherapy for head and neck cancer. In 533 head and neck cancer patients treated by curative radiotherapy, changes in weight and QOL were assessed between baseline (before radiotherapy) and follow-up (12 wk after the start of radiotherapy). Patients were categorized into 4 weight loss categories: 0%, 0.1%–5.0%, 5.1%–10.0%, and >10% weight loss. The association between weight loss and change in QOL was analyzed by linear regression analysis, adjusted for sociodemographic and tumor-related characteristics, and additionally for disease specific symptoms and tube feeding. Thirty percent of patients lost 0.1%–5.0% weight, 26% lost 5.1%–10.0% weight, and 24% lost >10% weight. Adjusted regression analyses showed a significant association between weight loss and deterioration of global QOL, physical functioning, social functioning, social eating, and social contact. After additional adjustment for disease-specific symptoms and tube feeding, weight loss (>10%) remained significantly associated with global QOL, social eating, and social contact (P < 0.05). More than 10% weight loss during and directly after radiotherapy has a significant impact on social eating, social contact, and QOL in head and neck cancer patients.


Journal of Clinical Pathology | 2006

Expression profiling and prediction of distant metastases in head and neck squamous cell carcinoma

Boudewijn J. M. Braakhuis; Asaf Senft; R de Bree; J de Vries; B Ylstra; Jacqueline Cloos; Dirk J. Kuik; C.R. Leemans; Ruud H. Brakenhoff

Background: For breast and prostate cancer, a gene expression signature of the tumour is associated with the development of distant metastases. Regarding head and neck squamous cell carcinoma (HNSCC), the only known risk factor is the presence of ⩾3 tumour-positive lymph nodes. Aim: To evaluate whether a HNSCC gene expression signature can discriminate between the patients with and without distant metastases. Methods: Patients with HNSCC with and without distant metastases had >3 tumour-positive lymph nodes, and did not differ with respect to other risk factors. Statistical analysis was carried out using Student’s t test, as well as statistical analysis of microarrays (SAM), to assess the false discovery rate for each gene. These analyses were supplemented with a newly developed method that computed deviations from gaussian-order statistics (DEGOS). To validate the platform, normal mucosa of the head and neck was included as control. Results: 2963 genes were differently expressed between HNSCC and normal mucosa (t test; p<0.01). More rigorous statistical analysis with SAM confirmed the differential expression of most genes. The comparison of genes in HNSCC with and without metastases showed 150 differently expressed genes (t test; p<0.01), none of which, however, could be confirmed using SAM or DEGOS. Conclusions: No evidence for a metastasis signature is found, and gene expression profiling of HNSCC has seemingly no value in determining the risk of developing distant metastases. The absence of such a signature can be understood when it is realised that, for HNSCC in contrast with breast cancer, the lymph nodes are a necessary in-between station for haematogenous spread.


Cancer Prevention Research | 2009

Screening for Oral Precancer with Noninvasive Genetic Cytology

Jantine F. Bremmer; A.P. Graveland; Arjen Brink; Boudewijn J. M. Braakhuis; Dirk J. Kuik; C.R. Leemans; Elisabeth Bloemena; I. van der Waal; Ruud H. Brakenhoff

Oral squamous cell carcinomas develop in precancerous fields consisting of genetically altered mucosal epithelial cells. These precancerous fields may appear as clinically visible lesions, in particular, oral leukoplakia, but the large majority remains clinically undetectable. The aim of this study was to assess the potential value of a noninvasive screening approach to detect precancerous fields. As a first step, we developed a suitable assay and investigated 25 leukoplakia patients and 20 noncancer control subjects. Exfoliated cells were removed by a brush from multiple small areas of the oral mucosa, including the leukoplakia. Brushed samples were investigated for allelic imbalance (AI) at chromosomes 3p, 9p, 11q, and 17p using microsatellite markers known to show frequent alterations in oral precancer. AI was absent in all (137) of the samples of the 20 control subjects, yielding a specificity of 100%. AI was detected in exfoliated cell samples of 40% (10 of 25) of the leukoplakia lesions studied. Genetic changes were also found outside the leukoplakia lesions. Most frequent was AI at 9p (9 of 10). The noninvasive assay was validated against the biopsy results of the leukoplakia lesions yielding an estimate of sensitivity of 78% (7 of 9) and a positive predictive value of 100% (7 of 7). Altogether, these results show the feasibility of a noninvasive genetic screening approach for the detection and monitoring of oral precancer. This assay could therefore contribute to the secondary prevention of oral squamous cell carcinoma. The assay also shows promise for the detection of precancerous changes that are not macroscopically visible.


The Journal of Nuclear Medicine | 2013

Pilot Study on the Feasibility of PET/CT Lymphoscintigraphy with 89Zr-Nanocolloidal Albumin for Sentinel Node Identification in Oral Cancer Patients

Derrek A. Heuveling; A. van Schie; Danielle J. Vugts; N.H. Hendrikse; Maqsood Yaqub; Otto S. Hoekstra; K.H. Karagozoglu; C.R. Leemans; G.A.M.S. van Dongen; R. de Bree

With conventional imaging techniques such as planar lymphoscintigraphy and SPECT/CT, preoperative sentinel node (SN) identification can be difficult when the SN is near the primary tumor, as is the case in floor-of-mouth carcinomas. PET/CT lymphoscintigraphy may improve the detection and localization of such SNs. Methods: In this study, the clinical feasibility of PET/CT lymphoscintigraphy using 89Zr-nanocolloidal albumin was evaluated in 5 oral cancer patients. PET/CT lymphoscintigraphy was performed after peritumoral injection of 89Zr-nanocolloidal albumin. The routine SN procedure, including SPECT/CT using 99mTc-nanocolloidal albumin, was performed on the same patients 7–9 d after the injection of 89Zr-nanocolloidal albumin. Results: Comparison of radiocolloid distribution on PET/CT and SPECT/CT showed identical drainage patterns. Moreover, PET/CT was able to identify additional foci near the primary tumor. Conclusion: This pilot PET/CT study on SN detection indicated that lymphoscintigraphy using 89Zr-nanocolloidal albumin is feasible.


Clinical Otolaryngology | 2005

Screening for distant metastases in patients with head and neck cancer: what is the current clinical practice?

Jolijn Brouwer; R. de Bree; Otto Hoekstra; Johannes A. Langendijk; Jonas A. Castelijns; C.R. Leemans

Objectives:  The detection of distant metastases during screening influences the choice of treatment in patients with head and neck squamous cell carcinoma (HNSCC). There is no consensus on the diagnostic technique that has to be used nor on the subgroup of HNSCC patients that may benefit from screening.


Histopathology | 2008

Deregulated expression of p16INK4a and p53 pathway members in benign and malignant myoepithelial tumours of the salivary glands

Hedy Vekony; K. Röser; T. Löning; F.M. Raaphorst; C.R. Leemans; I. van der Waal; Elisabeth Bloemena

Aims:  Myoepithelial salivary gland tumours are uncommon and follow an unpredictable biological course. The aim was to examine their molecular background to acquire a better understanding of their clinical behaviour.


Annals of Oncology | 2014

Best practices in the management of the psycho-oncologic aspects of head and neck cancer patients: recommendations from the European Head and Neck Cancer Society Make Sense Campaign

M. Reich; C.R. Leemans; Jan B. Vermorken; Jacques Bernier; L. Licitra; S. Parmar; W. Golusinski; Jean-Louis Lefebvre

Squamous cell carcinoma of the head and neck (SCCHN) is considered a worldwide health care problem. The majority of patients have a history of alcohol abuse and high-level tobacco consumption; however, SCCHN is also associated with exposure to viruses including human papillomavirus (HPV) and Epstein-Barr virus. A major problem facing SCCHN patients is that their disease is often diagnosed at an advanced stage where treatment options may not be curative, or can have severe post-treatment consequences. Confronted with their diagnosis and treatment options, the patient can express a range of emotional reactions which may lead to maladaptive coping. During the SCCHN patient journey, there are a number of stages where emotional support could be offered. A point of contact should be allocated to help patients navigate these stages and deliver practical emotive support (such as encouraging attendance at hospital appointments, compliance with lifestyle modifications and treatment adherence), and to identify if or when more advanced emotive support, in the form of a mental health professional, might be needed. This role might be carried out by a representative within the multidisciplinary health care team (e.g. a nurse). While optimal care is provided by specialist health care professionals, each with specific roles and responsibilities during the patient journey, all are important in screening for emotional distress and providing referral to the mental health team. This article reviews the key points for delivering emotional support to SCCHN patients at each stage of their care. Emotional problems cannot be ignored in SCCHN patients if optimal outcomes are to be achieved, particularly as therapeutic options extend overall survival for many patients. Health care professionals must be able to implement efficient screening for psychological distress to support patients compliance to their care and treatment. They must also be able to recognize when to refer patients at risk for pharmacological and/or psychotherapeutic interventions.


Oral Oncology | 2014

Patient-reported symptom questionnaires in laryngeal cancer: Voice, speech and swallowing

Rico N. P. M. Rinkel; I.M. Verdonck-de Leeuw; N. van den Brakel; R. de Bree; Simone E. J. Eerenstein; N.K. Aaronson; C.R. Leemans

OBJECTIVES To validate questionnaires on voice, speech, and swallowing among laryngeal cancer patients, to assess the need for and use of rehabilitation services, and to determine the association between voice, speech, and swallowing problems, and quality of life and distress. MATERIALS AND METHODS Laryngeal cancer patients at least three months post-treatment completed the VHI (voice), SHI (speech), SWAL-QOL (swallowing), EORTC QLQ-C30, QLQ-HN35, HADS, and study-specific questions on rehabilitation. RESULTS Eighty-eight patients and 110 healthy controls participated. Cut off scores of 15, 6, and 14 were defined for the VHI, SHI, and SWAL-QOL (sensitivity > 90%; specificity > 80%). Based on these scores, 56% of the patients reported voice, 63% speech, and 54% swallowing problems. VHI, SHI, and SWAL-QOL scores were associated significantly with quality of life (EORTC QLQ-C30 global quality of life scale) (r = .43 (VHI and SHI) and r = .46 (SWAL-QOL)) and distress (r = .50 (VHI and SHI) and r = .58 (SWAL-QOL)). In retrospect, 32% of the patients indicated the need for rehabilitation at time of treatment, and 81% of these patients availed themselves of such services. Post-treatment, 8% of the patients expressed a need for rehabilitation, and 20% of these patients actually made use of such services. CONCLUSION Psychometric characteristics of the VHI, SHI, and SWAL-QOL in laryngeal cancer patients are good. The prevalence of voice, speech, and swallowing problems is high, and clearly related to quality of life and distress. Although higher during than after treatment, the perceived need for and use of rehabilitation services is limited.

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R. de Bree

VU University Medical Center

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P. Doornaert

VU University Medical Center

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Johannes A. Langendijk

University Medical Center Groningen

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B.J. Slotman

VU University Amsterdam

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Elisabeth Bloemena

VU University Medical Center

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Dirk J. Kuik

VU University Medical Center

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D. Rietveld

VU University Medical Center

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Ruud H. Brakenhoff

VU University Medical Center

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