10 results on '"Pameijer, Frank A."'
Search Results
2. Systematic review of the diagnostic value of magnetic resonance imaging for early glottic carcinoma.
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van Egmond, Sylvia L., Stegeman, Inge, Pameijer, Frank A., Bluemink, Johanna J., Terhaard, Chris H., and Janssen, Luuk M.
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MAGNETIC resonance imaging ,SQUAMOUS cell carcinoma ,ONCOLOGY ,RADIOTHERAPY ,LARYNGOSCOPY - Abstract
Objective: In early glottic cancer, accurate assessment of tumor extension, including depth infiltration, is of great importance for both staging, therapeutic approach and systematic comparison of data. Our goal was to assess the diagnostic value of MRI in pre‐therapeutic staging of primary early stage (T1 and T2) glottic carcinoma. Study design: Systematic review of literature. Methods: We conducted a systematic search in Pubmed, Embase, and Scopus up to September 23, 2016. Included studies were selected and critically appraised for relevance and validity. Results: Seven out of 938 unique articles were selected, including 64 cases. MRI over‐staged 6% and under‐staged 13% of cT1 and cT2 tumors. However, available data is heterogeneous, very limited and mainly based on subanalysis of a small amount of patients. Reported MRI protocols appear to be suboptimal for small laryngeal lesions. Diagnostic value of MRI for subtle depth infiltration or laryngeal anatomical subsites (eg, laryngeal ventricle, vocal cord, etc.) could not be assessed. Conclusions: More studies are needed to assess the diagnostic value of MRI for small glottic tumors. [ABSTRACT FROM AUTHOR]
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- 2018
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3. GTV delineation in supraglottic laryngeal carcinoma: interobserver agreement of CT versus CT-MR delineation.
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Jager, Elise Anne, Kasperts, Nicolien, Caldas-Magalhaes, Joana, Philippens, Mariëlle E. P., Pameijer, Frank A., Terhaard, Chris H. J., and Raaijmakers, Cornelis P. J.
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RADIOTHERAPY ,MAGNETIC resonance imaging ,BIOPSY ,GADOLINIUM ,LARYNGEAL cancer ,THERAPEUTICS - Abstract
Background: GTV delineation is the first crucial step in radiotherapy and requires high accuracy, especially with the growing use of highly conformal and adaptive radiotherapy techniques. If GTV delineations of observers concord, they are considered to be of high accuracy. The aim of the study is to determine the interobserver agreement for GTV delineations of supraglottic laryngeal carcinoma on CT and on CT combined with MR-images and to determine the effect of adding MR images to CT-based delineation on the delineated volume and the interobserver agreement. Methods: Twenty patients with biopsy proven T1-T4 supraglottic laryngeal cancer, treated with curative intent were included. For all patients a contrast enhanced planning CT and a 1.5-T MRI with gadolinium were acquired in the same head-and-shoulder mask for fixation as used during treatment. For MRI, a two element surface coil was used as a receiver coil. Three dedicated observers independently delineated the GTV on CT. After an interval of 2 weeks, a set of co-registered CT and MR-images was provided to delineate the GTV on CT. Common volumes (C) and encompassing volumes (E) were calculated and C/E ratios were determined for each pair of observers. The conformity index general (CIgen) was used to quantify the interobserver agreement. Results: In general, a large variation in interobserver agreement was found for CT (range: 0.29-0.77) as well as for CT-MR delineations (range: 0.17-0.80). The mean CIgen for CT (0.61) was larger compared to CT-MR (0.57) (p = 0.032). Mean GTV volume delineated on CT-MR (6.6 cm³) was larger compared to CT (5.6 cm³) (p = 0.002). Conclusion: Delineation on CT with co-registered MR-images resulted in a larger mean GTV volume and in a decrease in interobserver agreement compared to CT only delineation for supraglottic laryngeal carcinoma. [ABSTRACT FROM AUTHOR]
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- 2015
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4. Semi-automated primary tumor volume measurements by dynamic contrast-enhanced MRI in patients with head and neck cancer.
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Lodder, Wouter L., Gilhuijs, KENneth G. A., Lange, Charlotte A. H., Pameijer, Frank A., Balm, Alfons J. M., and van dEN Brekel, Michiel W. M.
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HEAD & neck cancer ,STATISTICAL correlation ,TUMORS ,VOLUME measurements ,RADIOTHERAPY ,SQUAMOUS cell carcinoma ,LYMPH nodes - Abstract
Background Tumor volume is a significant prognostic factor in the treatment of malignant head and neck tumors. Unfortunately, it is not routinely measured because of the workload involved. Methods Twenty-one patients, between 2009 and 2010, were studied. Dynamic contrast-enhanced MRI (DCE-MRI) at 3.0T was performed. A workstation previously developed for semi-automated segmentation of breast cancers on DCE-MRI was used to segment the head and neck cancers. The Pearson correlation analysis was used to assess the agreement between volumetric measurements and the manually derived gross tumor volume (GTV). Results In 90.5% of the patients (19 of 21) correlation could be made between DCE-MRI and the manually derived GTV. The Pearson correlation coefficient between the automatically derived tumor volume at DCE-MRI and the manually derived GTVs was R
2 = 0.95 ( p < .001). Conclusion Semi-automated tumor volumes on DCE-MRI were representative of those derived from the manually derived GTV (R2 = 0.95; p < .001). © 2012 Wiley Periodicals, Inc. Head Neck, 2013 [ABSTRACT FROM AUTHOR]- Published
- 2013
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5. Tumor volume as prognostic factor in chemoradiation for advanced head and neck cancer.
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Knegjens, Joost L., Hauptmann, Michael, Pameijer, Frank A., Balm, Alfons J., Hoebers, Frank J., de Bois, Josien A., Kaanders, Johannes H., van Herpen, Carla M., Verhoef, Cornelia G., Wijers, Oda B., Wiggenraad, Ruud G., Buter, Jan, and Rasch, Coen R.
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HEAD & neck cancer ,SQUAMOUS cell carcinoma ,METASTASIS ,RADIOTHERAPY ,MAGNETIC resonance imaging ,MULTIVARIATE analysis ,PATIENTS - Abstract
Background. Tumor volume is an important predictor of outcome in radiotherapy alone. Its significance in concomitant chemoradiation (CCRT) is much less clear. We analyzed the prognostic value of primary tumor volume for advanced head and neck squamous cell carcinoma (HNSCC) treated with CCRT. Methods. Three hundred sixty patients treated with definitive CCRT for advanced HNSCC were selected. The pretreatment MRI or CT scan was used to calculate the primary tumor volume. Median follow-up was 19.8 months. Results. The average primary tumor volume was 37.0 cm
3 (range, 2.1-182.7 cm3 ; median, 28.7 cm3 ). Multivariate analysis showed a significant effect of tumor volume on local control. The hazard ratio for a local recurrence increased by 14% per 10 cm3 volume increase (95% CI, 8% to 21%). There was no significant independent effect of T and N status on local control. Conclusion. For advanced HNSCC, tumor volume is more powerful for predicting outcome after CCRT than TNM status. [ABSTRACT FROM AUTHOR]- Published
- 2011
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6. Prognostic value of primary tumor volume after concurrent chemoradiation with daily low-dose cisplatin for advanced-stage head and neck carcinoma.
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Hoebers, Frank J. P., Pameijer, Frank A., de Bois, Josien, Heemsbergen, Wilma, Balm, Alfons J. M., Schornagel, Jan H., and Rasch, Coen R. N.
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HEAD & neck cancer ,CISPLATIN ,TUMORS ,PROGNOSTIC tests ,SQUAMOUS cell carcinoma - Abstract
Background. The purpose of this study was to evaluate the prognostic value of tumor volume in head and neck squamous cell carcinoma treated with chemoradiation. Methods. Forty-six patients were treated with radiotherapy and cisplatin (6 mg/m
2 IV x20, daily). Baseline primary tumor volume was recorded from MRI scans. The prognostic impact of tumor volume and other factors for locoregional control, disease-free survival (DFS), and overall survival (OS) was tested. Results. Mean tumor volume was 28 cm3 (median 23 cm3 ; range, 3–112). The locoregional control rate at 3 years was 81% for patients with tumor volumes- Published
- 2008
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7. Prospective comparative study of MRI including diffusion-weighted images versus FDG PET-CT for the detection of recurrent head and neck squamous cell carcinomas after (chemo)radiotherapy.
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Driessen, Juliette P., Peltenburg, Boris, Philippens, Marielle E.P., Huijbregts, Julia E., Pameijer, Frank A., de Bree, Remco, Janssen, Luuk M., and Terhaard, Chris H.J.
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HEAD & neck cancer , *SQUAMOUS cell carcinoma , *DIFFUSION magnetic resonance imaging , *LONGITUDINAL method , *RADIOTHERAPY - Abstract
Objective: This prospective study aims to test if MRI including diffusion weighted images can replace FDG PET-CT in the diagnosis of patients with suspicion of local recurrent head and neck squamous cell carcinomas after (chemo)radiation.Methods: Seventy-five patients suspected of local recurrence underwent a MRI and a FDG PET-CT. Qualitative assessment of the images was performed. Reference standard was the results of biopsy or the absence of a recurrence during follow up.Results: Seventy patients were included. Fifty percent had local recurrence. FDG PET-CT had accuracy of 71% compared to 73% for MRI. The sensitivity and specificity were 97% compared to 69% and 46% compared to 77% for FDG PET-CT and MRI respectively.Conclusions: MRI showed similar diagnostic accuracy, superior specificity but inferior sensitivity compared to FDG PET-CT. Based on current results, we consider MRI including diffusion weighted sequences unable to replace FDG PET-CT as a single imaging modality when local recurrent disease of HNSCC after (C)RT is suspected. [ABSTRACT FROM AUTHOR]- Published
- 2019
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8. Prostate tumor delineation using multiparametric magnetic resonance imaging: Inter-observer variability and pathology validation.
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Steenbergen, Peter, Haustermans, Karin, Lerut, Evelyne, Oyen, Raymond, De Wever, Liesbeth, Van den Bergh, Laura, Kerkmeijer, Linda G.W., Pameijer, Frank A., Veldhuis, Wouter B., van der Voort van Zyp, Jochem R.N., Pos, Floris J., Heijmink, Stijn W., Kalisvaart, Robin, Teertstra, Hendrik J., Dinh, Cuong V., Ghobadi, Ghazaleh, and van der Heide, Uulke A.
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PROSTATE tumors treatment , *MAGNETIC resonance imaging , *RADIATION doses , *CANCER radiotherapy , *HEALTH outcome assessment , *ONCOLOGY - Abstract
Background and purpose Boosting the dose to the largest (dominant) lesion in radiotherapy of prostate cancer may improve treatment outcome. The success of this approach relies on the detection and delineation of tumors. The agreement among teams of radiation oncologists and radiologists delineating lesions on multiparametric magnetic resonance imaging (mp-MRI) was assessed by measuring the distances between observer contours. The accuracy of detection and delineation was determined using whole-mount histopathology specimens as reference. Material and methods Six observer teams delineated tumors on mp-MRI of 20 prostate cancer patients who underwent a prostatectomy. To assess the inter-observer agreement, the inter-observer standard deviation (SD) of the contours was calculated for tumor sites which were identified by all teams. Results Eighteen of 89 lesions were identified by all teams, all were dominant lesions. The median histological volume of these was 2.4 cm 3 . The median inter-observer SD of the delineations was 0.23 cm. Sixty-six of 69 satellites were missed by all teams. Conclusion Since all teams identify most dominant lesions, dose escalation to the dominant lesion is feasible. Sufficient dose to the whole prostate may need to be maintained to prevent under treatment of smaller lesions and undetected parts of larger lesions. [ABSTRACT FROM AUTHOR]
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- 2015
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9. Magnetic Resonance Imaging Protocol Optimization for Delineation of Gross Tumor Volume in Hypopharyngeal and Laryngeal Tumors
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Verduijn, Gerda M., Bartels, Lambertus W., Raaijmakers, Cornelis P.J., Terhaard, Chris H.J., Pameijer, Frank A., and van den Berg, Cornelis A.T.
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MAGNETIC resonance imaging , *RADIOTHERAPY , *HYPOPHARYNX diseases , *TOMOGRAPHY , *SIGNAL-to-noise ratio ,LARYNGEAL tumors - Abstract
Purpose: To optimize the use of MRI for delineation of gross tumor volume for radiotherapy treatment planning purposes in hypopharyngeal and laryngeal tumors. Methods and Materials: Magnetic resonance images (T1 weighted and T2 weighted) of a healthy volunteer were acquired using a 1.5 T and 3.0 T MR scanner. Various receiver coils were investigated that were compatible with the immobilization mask needed for reliable coregistration with computed tomography data. For the optimal receiver coil, the influence of resolution, slice thickness, and strength of magnetic field on the signal-to-noise ratio (SNR) was studied. Feasibility of the definitive protocol was tested on patients with hypopharyngeal (n = 19) and laryngeal (n = 42) carcinoma. Results: Large differences in SNR were obtained for the various coils. The SNR values obtained using surface coils that were compatible with the immobilization mask were three times higher than those obtained using a standard head-and-neck coil and five times higher than those obtained using a body coil. High-resolution images (0.4 × 0.4 × 4 mm3) showed superior anatomic detail and resulted in a 4-min scan time. Image quality at 3.0 T was not significantly better compared with 1.5 T. In 3 patients the MR study could not be performed; for 5 patients images were severely deteriorated by motion artefacts. High-quality MR images were obtained in 53 patients. Conclusions: High-resolution MR images of the hypopharynx and larynx can be obtained in the majority of patients using surface receiver coils in combination with the radiotherapy mask. These MR images can be successfully used for tumor delineation in radiotherapy. [Copyright &y& Elsevier]
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- 2009
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10. Dysphagia and aspiration after chemoradiotherapy for head-and-neck cancer: Which anatomic structures are affected and can they be spared by IMRT?
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Eisbruch, Avraham, Schwartz, Marco, Rasch, Coen, Vineberg, Karen, Damen, Eugene, Van As, Corina J., Marsh, Robin, Pameijer, Frank A., and Balm, Alfons J. M.
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DRUG therapy , *VIDEOFLUOROSCOPY , *DIAGNOSTIC imaging , *ANTINEOPLASTIC agents - Abstract
Purpose: To identify the anatomic structures whose damage or malfunction cause late dysphagia and aspiration after intensive chemotherapy and radiotherapy (RT) for head-and-neck cancer, and to explore whether they can be spared by intensity-modulated RT (IMRT) without compromising target RT.Methods and materials: A total of 26 patients receiving RT concurrent with gemcitabine, a regimen associated with a high rate of late dysphagia and aspiration, underwent prospective evaluation of swallowing with videofluoroscopy (VF), direct endoscopy, and CT. To assess whether the VF abnormalities were regimen specific, they were compared with the VF findings of 6 patients presenting with dysphagia after RT concurrent with high-dose intra-arterial cisplatin. The anatomic structures whose malfunction was likely to cause each of the VF abnormalities common to both regimens were determined by literature review. Pre- and posttherapy CT scans were reviewed for evidence of posttherapy damage to each of these structures, and those demonstrating posttherapy changes were deemed dysphagia/aspiration-related structures (DARS). Standard three-dimensional (3D) RT, standard IMRT (stIMRT), and dysphagia-optimized IMRT (doIMRT) plans in which sparing of the DARS was included in the optimization cost function, were produced for each of 20 consecutive patients with advanced head-and-neck cancer.Results: The posttherapy VF abnormalities common to both regimens included weakness of the posterior motion of the base of tongue, prolonged pharyngeal transit time, lack of coordination between the swallowing phases, reduced elevation of the larynx, and reduced laryngeal closure and epiglottic inversion, contributing to a high rate of aspiration. The anatomic structures whose malfunction was the likely cause of each of these abnormalities, and that also demonstrated anatomic changes after RT concurrent with gemcitabine doses associated with dysphagia and aspiration, were the pharyngeal constrictor muscles (median thickness near midline 2.5 mm before therapy vs. 7 mm after therapy; p = 0.001), the supraglottic larynx (median thickness, 2 mm before therapy vs. 4 mm after therapy; p < 0.001), and, similarly, the glottic larynx. The constrictors and the glottic and supraglottic larynx were, therefore, deemed the DARS. The lowest maximal dose delivered to a stricture volume was 50 Gy. Reducing the volumes of the DARS receiving ≥50 Gy (V50) was, therefore, a planning and evaluation goal. Compared with the 3D plans, stIMRT reduced the V50 of the pharyngeal constrictors by 10% on average (range, 0–36%, p < 0.001), and doIMRT reduced these volumes further, by an additional 10% on average (range, 0–38%; p <0.001). The V50 of the larynx (glottic + supraglottic) was reduced marginally by stIMRT compared with 3D (by 7% on average, range, 0–56%; p = 0.054), and doIMRT reduced these volumes by an additional 11%, on average (range, 0–41%; p = 0.002). doIMRT reduced laryngeal V50 compared with 3D, by 18% on average (range 0–61%; p = 0.001). Certain target delineation rules facilitated sparing of the DARS by IMRT. The maximal DARS doses were not reduced by IMRT because of their partial overlap with the targets. stIMRT and doIMRT did not differ in target doses, parotid gland mean dose, spinal cord, or nonspecified tissue maximal dose.Conclusions: The structures whose damage may cause dysphagia and aspiration after intensive chemotherapy and RT are the pharyngeal constrictors and the glottic and supraglottic larynx. Compared with 3D-RT, moderate sparing of these structures was achieved by stIMRT, and an additional benefit, whose extent varied among the patients, was gained by doIMRT, without compromising target doses. Clinical validation is required to determine whether the dosimetric gains are translated into clinical ones. [Copyright &y& Elsevier]
- Published
- 2004
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