There is a pending need for prognostic and predictive biomarkers in the treatment of patients with colorectal cancer.This thesis describes the prognostic and predictive application of the tumor... Show moreThere is a pending need for prognostic and predictive biomarkers in the treatment of patients with colorectal cancer.This thesis describes the prognostic and predictive application of the tumor-stroma ratio (TSR) in colorectal cancer, focusing on expanding current clinical-pathological standards and combining TSR with other diagnostic parameters. The TSR is a microscopy scoring method performed on hematoxylin-eosin stained tissue slides used for routine pathology assessment, and has proven to be a robust prognostic maker. Here, we investigate whether the TSR also exhibits predictive value with regard to adjuvant targeted therapy in stage II and III colon cancer. Moreover, exploring the value of collagen fiber organization in the intratumoral stroma, as well as combining this parameter with the TSR. Finally, expanding the application of the TSR with radiological diagnostics in rectal cancer. Assessing is there is a correlation between TSR and apparent diffusion coefficient values obtained from diagnostically performed MRI-DWI scans, in order to determine if there is potential with regards to neoadjuvant treatment choices or patient follow-up. Show less
Patients with diabetes mellitus have the highest mortality risk within the dialysis population. The presence of chronic kidney disease (CKD) in patients with diabetes is also strongly related to... Show morePatients with diabetes mellitus have the highest mortality risk within the dialysis population. The presence of chronic kidney disease (CKD) in patients with diabetes is also strongly related to impaired quality of life. Research is warranted to prevent progressive diabetic kidney disease, improve quality of life and reduce mortality in this vulnerable population. In order to improve survival, more knowledge about which patients have the highest mortality risk and which risk factors and co-morbid conditions contribute to this increased mortality risk is essential. In this thesis we focussed on clinical aspects of the relation between diabetes mellitus and kidney disease, from hyperfiltration to dialysis. In chapter 2 we assessed many different measures of glucose metabolism and their association with kidney function among Dutch middle-aged adults. In chapter three and four we compared survival of dialysis patients with diabetes mellitus as underlying cause of the renal failure versus dialysis patients with diabetes mellitus as a co-morbid condition only. In chapter five we aimed to develop a prediction model for 1-year mortality in diabetic dialysis patients. Furthermore in chapter six we compared survival after amputation in diabetic dialysis patients to non-diabetic dialysis patients. Show less
This thesis describes the detailed method of scoring the tumor-stroma ratio and the different possibilities to use it in routine clinical diagnostics, for different types of cancer. It can be used... Show moreThis thesis describes the detailed method of scoring the tumor-stroma ratio and the different possibilities to use it in routine clinical diagnostics, for different types of cancer. It can be used not only for prognostic purposes, but it might also be useful for predicting the response on neo-adjuvant therapy. As it is an easy and cheap method, based on routine hematoxylin-eosin stained tissue slides used for daily pathology routine, it can be implemented in clinical diagnostics with little effort. Show less
In this thesis, the transition from a population-based approach to individualized therapy for the prevention of VT following lower-leg cast immobilization and knee arthroscopy is discussed.
One of the main questions in Ewing sarcoma treatment is to identify low-risk patients that can be treated with less intensive treatment so that toxicity and the occurrence of long-term adverse... Show moreOne of the main questions in Ewing sarcoma treatment is to identify low-risk patients that can be treated with less intensive treatment so that toxicity and the occurrence of long-term adverse effects can be limited while still maintaining high cure rates or to identify those patients for whom treatment is expected to have limited benefit. Furthermore, to identify high-risk patients in which treatment needs to be intensified to improve outcome. Selection of risk groups and adjusted treatment allows for early decision making, will help to improve future outcomes and assists in clinical trial design. Additionally, treatment of Ewing sarcoma is multimodal and surgery, if feasible, is crucial for curative management. However, accurate detection and localization of tumor boundaries, especially in anatomical complex locations such as the pelvic is challenging. Inadequate surgical margins lead to a higher risk of local recurrence which has major impact on oncological outcome. Developments in intra-operative imaging, like CT-based navigation systems and near infrared (NIR)fluorescence guided surgery (FGS) make accurate defining and localization of surgical margins possible. They represent a whole new field of precision medicine and provide new treatment options for patients, thereby improving function outcome and healthcare quality. Show less
Postpartum haemorrhage, in this thesis defined as blood loss above 1000mL within the first 24 hours after birth, remains a major cause of maternal morbidity and mortality with an incidence that... Show morePostpartum haemorrhage, in this thesis defined as blood loss above 1000mL within the first 24 hours after birth, remains a major cause of maternal morbidity and mortality with an incidence that seems to be increasing over the last decade. In this thesis we focussed on improvement of prognostic and diagnostic strategies for major obstetric haemorrhage, which may subsequently lead to a reduction of severe maternal morbidity, mortality and need for surgical interventions. In pursuit of this aim, research questions were posed corresponding to all three phases leading up to adverse outcome due to postpartum haemorrhage: pregnancy (prior to childbirth), early postpartum haemorrhage and persistent postpartum haemorrhage. In the first part of this thesis we focused on prediction of postpartum haemorrhage.Bleeding assessment tools were found to have no predictive value for postpartum haemorrhage. The change of coagulation parameters during the course of postpartum haemorrhage was described, and fibrinogen was found to be an early predictor of a worse outcome of postpartum haemorrhage. The association between fibrinogen measured by the Clauss method and ROTEM Fibtem was described in this thesis. Show less
The main aim of this thesis is to explore risk factors associated to an increased risk of adverse outcomes for heart failure (HF) patients and improve the early re-admission or mortality prediction... Show moreThe main aim of this thesis is to explore risk factors associated to an increased risk of adverse outcomes for heart failure (HF) patients and improve the early re-admission or mortality prediction in HF. Data from two studies (OPERA-HF study in the UK and SAPHIRE study in US) has been used to explore a wide range of variables as potential risk factors. We found that depression is a significant and independent predictor of all-cause mortality among HF patients. Depression was also significantly associated with recurrent events: unplanned readmission or mortality. Other psychosocial or non-clinical variables independently associated with increasing risk of recurrent events in the year following discharge after a HF hospital admission were: presence of frailty, moderate-to-severe anxiety, living alone and the presence of cognitive impairment. We then used data from the OPERA-HF study to develop a 30-day composite outcome model and to explore the added predictive value of non-clinical predictors to early outcomes: 30-day unplanned readmission or mortality. The performance of the model improved by including physical frailty and social support next to clinical variables. The transportability of the model to a different geography was proved in the external validation of the model on the SAPHIRE study data. Show less
The scope of this thesis spanned several issues in the measurement and evaluation of OD. The screening, assessment, and treatment effect for OD have been covered,with a special emphasis on... Show moreThe scope of this thesis spanned several issues in the measurement and evaluation of OD. The screening, assessment, and treatment effect for OD have been covered,with a special emphasis on patient self-evaluation. Show less
SDHD-related head and neck paragangliomas are, hereditary and generally benign, neuroendocrine tumors that arise from paraganglionic tissue associated with the parasympathetic nervous system.... Show moreSDHD-related head and neck paragangliomas are, hereditary and generally benign, neuroendocrine tumors that arise from paraganglionic tissue associated with the parasympathetic nervous system. The primary aim of this thesis was to gain more insight in the natural course of SDHD-related head and neck paragangliomas and ultimately improve surveillance and treatment strategies, as well as counseling of both patients and their family members. The risk of occult and metachronous paragangliomas, tumor growth, clinical progression and survival of SDHD germline mutation carriers were addressed. Show less
The work presented in this thesis focuses on methods for the construction of diagnostic rules based on clinical mass spectrometry proteomic data. Mass spectrometry has become one of the key... Show moreThe work presented in this thesis focuses on methods for the construction of diagnostic rules based on clinical mass spectrometry proteomic data. Mass spectrometry has become one of the key technologies for jointly measuring the expression of thousands of proteins in biological samples. However, the development of MS instrumentation gave rise to new statistical challenges in the processing and analysis of the acquired data. This is due to the complex nature of the spectral proteomic signal which is measured, as it consists of high-dimensional functions representing the within-patient proteome expression. This work considers new methods to respond to these challenges. Our main interest focuses on the comparison of mass spectral proteomic profiles collected from healthy individuals and cancer patients in the context of distinct case-control studies. A key objective in such studies is the construction of discriminant rules for distinguishing between individuals as to the presence or absence of the disease as well as for predicting the health status of future patients. We present a series of data analyses for distinct case-control cancer studies where we address these questions through the use of methodology specific for the type of data considered in each of the studies. Show less
The field of rheumatoid arthritis (RA) is moving into identification of patients as early as possible and the ultimate aim is to prevent RA becoming a chronic disease. To this end, we studied the... Show moreThe field of rheumatoid arthritis (RA) is moving into identification of patients as early as possible and the ultimate aim is to prevent RA becoming a chronic disease. To this end, we studied the phase of Clinically Suspect Arthralgia (CSA). Patients with arthralgia that were considered by the rheumatologist to have an increased risk to progress to RA (CSA) had indeed an increased risk of RA. In addition, subclinical MRI-inflammation preceded clinical arthritis with a few months. Future research will shed more light on processes underlying progression from CSA to RA and effectiveness of treatment initiation in the CSA phase. The severity of the course of RA is variable between patients and this cannot be yet accurately predicted. In this thesis, we performed studies that contributed to the understanding of these differences in severity. Three genetic risk factors for more severe joint damage progression (two non-HLA and one HLA variation) and one for arthritis persistence were identified. Further research on functional implications of the identified variants and whether they might be useful as biomarkers to guide treatment decisions is needed. Show less