71 research outputs found
Ultrasound examination of the head and neck
Structure of this thesis
Part I deals with basic bio-physics and bio-effects of clinical ultrasound of the head and
neck. Furthermore, the ultrasound anatomy of the head and neck is described and
illustrated. In addition, the technique of ultrasound guided fine needle aspiration biopsy
(UGFNAB) is outlined.
In part H the significThe fallibility of palpation and current diagnostic tests to detect subclinical (occult) nodal
disease in patients with upper aero-digestive tract cancer results in imperfect staging,
improper treatment and delayed identification of recurrences in the neck. With continuous
advances in imaging techniques (CT, MRI), the sensitivity for the detection of cervical
lymph nodes is true enough increasing, while the specificity for detecting metastasis with
these techniques remains low. An ideal diagnostic test should be suitable for screening,
demonstrating and excluding cervical metastasis. In addition, the test should have no
morbidity.
The diagnostic work-up of patients with a head and neck mass is another important
diagnostic problem. Although careful history taking and thorough ENT examination may be
sufficiently characteristic to permit diagnosis, every clinical diagnosis will be associated with
a certain degree of uncertainty. This uncertainty is mainly deterntined by the lintitations of
clinical exantination in differentiating between solid and cystic lesions on one hand, and the
establishment of exact anatontic properties on the other. In addition, there is a proportion of
lesions which, despite thorough diagnostic work-up. remain elusive and are subjected to
premature surgical exploration. CT may contribute to the pre-treatment work-up but is
associated with several important drawbacks: high costs, lintited availability, radiation
exposure and the need to use intravenous contrast.
A simple, uniformly reliable, non-invasive and cost-effective test would be beneficial in
these cases.
The low accuracy of current diagnostic methods in the assessment of cervical nodal disease
and the difficulties to evaluate head and neck masses actuated the present study, which
started in 1984. By that time small-parts ultrasound transducers had been developed. These
high-frequency transducers seemed better suited for examination of the superficial tissues in
the head and neck region than earlier ultrasound equipment. In close cooperation between
the departments of Radiology and Otorhinolaryngology and Head and Neck Surgery. a prospective
study on the value of ultrasound examination of the head and neck was designed.
The purpose of this study was to deterntine the values of palpation and ultrasound
examination in the assessment of cervical metastatic disease in patients with upper aerodigestive
tract cancer and in the evaluation of head and neck masses. An additional purpose
of this study was to appraise the adjunctive value of cytologic exantination in the above
mentioned clinical problem
Prioritization of surgical patients during the COVID-19 pandemic and beyond:A qualitative exploration of patients’ perspectives
IntroductionDuring the COVID-19 pandemic, prioritizing certain surgical patients became inevitable due to limited surgical capacity. This study aims to identify which factors patients value in priority setting, and to evaluate their perspective on a decision model for surgical prioritization.MethodsWe enacted a qualitative exploratory study and conducted semi-structured interviews with N = 15 patients. Vignettes were used as guidance. The interviews were transcribed and iteratively analyzed using thematic analysis.ResultsWe unraveled three themes: 1) general attitude towards surgical prioritization: patients showed understanding for the difficult decisions to be made, but demanded greater transparency and objectivity; 2) patient-related factors that some participants considered should, or should not, influence the prioritization: age, physical functioning, cognitive functioning, behavior, waiting time, impact on survival and quality of life, emotional consequences, and resource usage; and 3) patients’ perspective on a decision model: usage of such a model for prioritization decisions is favorable if the model is simple, uses trustworthy data, and its output is supervised by physicians. The model could also be used as a communication tool to explain prioritization dilemmas to patients.ConclusionSupport for the various factors and use of a decision model varied among patients. Therefore, it seems unrealistic to immediately incorporate these factors in decision models. Instead, this study calls for more research to identify feasible avenues and seek consensus
Prediction of survival with alternative modeling techniques using pseudo values
Background: The use of alternative modeling techniques for predicting patient survival is complicated by the fact that some alternative techniques cannot readily deal with censoring, which is essential for analyzing survival data. In the current study, we aimed to demonstrate that pseudo values enable statistically appropriate analyses of survival outcomes when used in seven alternative modeling techniques. Methods: In this case study, we analyzed survival of 1282 Dutch patients with newly diagnosed Head and Neck Squamous Cell Carcinoma (HNSCC) with conventional Kaplan-Meier and Cox regression analysis. We subsequently calculated pseudo values to reflect the individual survival patterns. We used these pseudo values to compare recursive partitioning (RPART), neural nets (NNET), logistic regression (LR) general linear models (GLM) and three variants of support vector machines (SVM) with respect to dichotomous 60-month survival, and continuous pseudo values at 60 months or estimated survival time. We used the area under the ROC curve (AUC) and the root of the mean squared error (RMSE) to compare the performance of these models using bootstrap validation. Results: Of a total of 1282 patients, 986 patients died during a median follow-up of 66 months (60-month survival: 52% [95% CI: 50%-55%]). The L
Surgical prioritization based on decision model outcomes is not sensitive to differences between the health-related quality of life values estimates of physicians and citizens
Purpose: Decision models can be used to support allocation of scarce surgical resources. These models incorporate health-related quality of life (HRQoL) values that can be determined using physician panels. The predominant opinion is that one should use values obtained from citizens. We investigated whether physicians give different HRQoL values to citizens and evaluate whether such differences impact decision model outcomes. Methods: A two-round Delphi study was conducted. Citizens estimated HRQoL of pre- and post-operative health states for ten surgeries using a visual analogue scale. These values were compared using Bland–Altman analysis with HRQoL values previously obtained from physicians. Impact on decision model outcomes was evaluated by calculating the correlation between the rankings of surgeries established using the physicians’ and the citizens’ values.Results: A total of 71 citizens estimated HRQoL. Citizens’ values on the VAS scale were − 0.07 points (95% CI − 0.12 to − 0.01) lower than the physicians’ values. The correlation between the rankings of surgeries based on citizens’ and physicians’ values was 0.96 (p < 0.001). Conclusion: Physicians put higher values on health states than citizens. However, these differences only result in switches between adjacent entries in the ranking. It would seem that HRQoL values obtained from physicians are adequate to inform decision models during crises.</p
Noncompliance to guidelines in head and neck cancer treatment; associated factors for both patient and physician
Background: Decisions on head and neck squamous cell carcinoma (HNSCC) treatment are widely recognized as being difficult, due to high morbidity, often involving vital functions. Some patients may therefore decline standard, curative treatment. In addition doctors may propose alternative, nonstandard treatments. Little attention is devoted, both in literature and in daily practice, to understanding why and when HNSCC patients or their physicians decline standard, curative treatment modalities. Our objective is to determine factors associated with noncompliance in head and neck cancer treatment for both patients and physicians and to assess the influence of patient compliance on prognosis. Methods: We did a retrospective study based on the medical records of 829 patients with primary HNSCC, who were eligible for curative treatment and referred to our hospital between 2010 and 2012. We analyzed treatment choice and reasons for nonstandard treatment decisions, survival, age, gender, social network, tumor site, cTNM classification, and comorbidity (ACE27). Multivariate analysis using logistic regression methods was performed to determine predictive factors associated with non-standard treatment following physician or patient decision. To gain insight in survival of the different groups of patients, we applied a Cox regression analysis. After checking the proportional hazards assumption for each variable, we adjusted the survival analysis for gender, age, tumor site, tumor stage, comorbidity and a history of having a prior tumor. Results: 17 % of all patients with a primary HNSCC did not receive standard curative treatment, either due to nonstandard treatment advice (10 %) or due to the patient choosing an alternative (7 %). A further 3 % of all patients refused any type of therapy, even though they were considered eligible for curative treatment. Elderliness, single marital status, female gender, high tumor stage and severe comorbidity are predictive factors. Patients declining standard treatment have a lower overall 3-year survival (34 % vs. 70 %). Conclusions: Predictive factors for nonstandard treatment decisions in head and neck cancer treatment differed between the treating physician and the patient. Patients who received nonstandard treatment had a lower overall 3-year survival. These findings should be taken into account when counselling patients in whom nonstandard treatment is considered
Head and neck cancer patients' preferences for individualized prognostic information: a focus group study
BACKGROUND: Head and Neck cancer (HNC) is characterized by significant mortality and morbidity. Treatment is often invasive and interferes with vital functions, resulting in a delicate balance between survival benefit and deterioration in quality of life (QoL). Therefore, including prognostic information during patient counseling can be of great importance. The first aim of this study was to explore HNC patients' preferences for receiving prognostic information: both qualitative (general terms like "curable cancer"), and quantitative information (numbers, percentages). The second aim of this study was to explore patients' views on "OncologIQ", a prognostic model developed to estimate overall survival in newly diagnosed HNC patients. METHODS: We conducted a single center qualitative study by organizing five focus groups with HNC patients (n = 21) and their caregivers (n = 19), categorized in: 1) small laryngeal carcinomas treated with radiotherapy or laser, 2) extensive oral cavity procedures, 3) total laryngectomy, 4) chemoradiation, 5) other treatments. The patients' perspective was the main focus. The interview guide consiste
Gene-expression of metastasized versus non-metastasized primary head and neck squamous cell carcinomas: A pathway-based analysis
Background: Regional lymph node metastasis is an important prognostic factor in head and neck squamous cell carcinoma (HNSCC) and plays a decisive role in the choice of treatment. Here, we present an independent gene expression validation study of metastasized versus non-metastasized HNSCC. Methods: We used a dataset recently published by Roepman et al. as reference dataset and an independent gene expression dataset of 11 metastasized and 11 non-metastasized HNSCC tumors as validation dataset. Reference and validation studies were performed on different microarray platforms with different probe sets and probe content. In addition to a supervised gene-based analysis, a supervised pathway-based analysis was performed, evaluating differences in gene expression for predefined tumorigenesis- and metastasis related gene sets. Results: The gene-based analysis showed 26 significant differentially expressed genes in the reference dataset, 21 of which were present on the microarray platform used in the validation study. 7 of these genes appeared to be significantly expressed in the validation dataset, but failed to pass the correction for multiple testing. The pathway-based analysis revealed 23 significant differentially expressed gene sets, 7 of which were statistically validated. These gene sets are involved in extracellular matrix remodeling (MMPs, MMP regulating pathways and the uPA system), hypoxia and angiogenesis (HIF1α regulated angiogenic factors and HIF1α regulated invasion). Conclusion: Pathways that are differentially expressed between metastasized and non-metastasized HNSCC are involved in the processes of extracellular matrix remodeling, hypoxia and angiogenesis. A supervised pathway-based analysis enhances the understanding of the biological context of the results, the comparability of results across different microarray studies, and reduces multiple testing problems by focusing on a limited number of pathways of interest instead of analyzing the large number of probes available on the microarray
Development and validation of Raman spectroscopic classification models to discriminate tongue squamous cell carcinoma from non-tumorous tissue
Background Currently, up to 85% of the oral resection specimens have inadequate resection margins, of which the majority is located in the deeper soft tissue layers. The prognosis of patients with oral cavity squamous cell carcinoma (OCSCC) of the tongue is negatively affected by these inadequate surgical resections. Raman spectroscopy, an optical technique, can potentially be used for intra-operative evaluation of resection margins.
Objective To develop in vitro Raman spectroscopy-based tissue classification models that discriminate OCSCC of the tongue from (subepithelial) non-tumorous tissue.
Materials and methods Tissue classification models were developed using Principal Components Analysis (PCA) followed by (hierarchical) Linear Discriminant Analysis ((h)LDA). The models were based on a training set of 720 histopathologically annotated Raman spectra, obtained from 25 tongue samples (11 OCSCC and 14 normal) of 10 patients, and were validated by means of an independent validation set of 367 spectra, obtained from 19 tongue samples (6 OCSCC and 13 normal) of 11 patients.
Results A PCA-LDA tissue classification model ‘tumor’ versus ‘non-tumorous tissue’ (i.e. surface squamous epithelium, connective tissue, muscle, adipose tissue, gland and nerve) showed an accuracy of 86% (sensitivity: 100%, specificity: 66%). A two-step PCA-hLDA tissue classification model ‘tumor’ versus ‘non-tumorous tissue’ showed an accuracy of 91%
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