Potential and limitations of diffusion-weighted magnetic resonance imaging in kidney, prostate, and bladder cancer including pelvic lymph node staging: a critical analysis of the literature

Diagnosis, staging, and treatment monitoring are still suboptimal for most genitourinary tumours. Diffusion-weighted magnetic resonance imaging (DW-MRI) has already shown promise as a noninvasive imaging modality in the early detection of microstructural and functional changes in several pathologies of various organs.

QUALITY OF LIFE: A POTENTIALLY USEFUL MEASURE TO INDICATE SUBCLINICAL FLARES IN CROHN'S DISEASE

While quality of life (QoL) is a well-recognised outcome measure of Crohn disease (CD) activity, its influence on other outcome measures, including exacerbation of CD is poorly understood. If QoL measures were to be associated with intestinal inflammatory activity, they might be useful for early detection of subclinical flares.

Assessment of melanocytic skin lesions with a high-definition laser Doppler imaging system

Early detection is a major goal in the management of malignant melanoma. Besides clinical assessment many noninvasive technologies such as dermoscopy, digital dermoscopy and in vivo laser scanner microscopy are used as additional methods. Herein we tested a system to assess lesional perfusion as a tool for early melanoma detection.

Tumor budding cells, cancer stem cells and epithelial-mesenchymal transition-type cells in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers with a 5-year survival rate of less than 5%. Moreover, PDAC escapes early detection and resists treatment. Multiple combinations of genetic alterations are known to occur in PDAC including mutational activation of KRAS, inactivation of p16/CDKN2A and SMAD4 (DPC4) and dysregulation of PTEN/PI3K/AKT signaling. Through their interaction with Wingless-INT pathway, the downstream molecules of these pathways have been implicated in the promotion of epithelial-mesenchymal transition (EMT). Emerging evidence has demonstrated that cancer stem cells (CSCs), small populations of which have been identified in PDAC, and EMT-type cells play critical roles in drug resistance, invasion, and metastasis in pancreatic cancer. EMT may be histologically represented by the presence of tumor budding which is described as the occurrence of single tumor cells or small clusters (<5) of dedifferentiated cells at the invasive front of gastrointestinal (including colorectal, oesophageal, gastric, and ampullary) carcinomas and is linked to poor prognosis. Tumor budding has recently been shown to occur frequently in PDAC and to be associated with adverse clinicopathological features and decreased disease-free and overall survival. The aim of this review is to present a short overview on the morphological and molecular aspects that underline the relationship between tumor budding cells, CSCs, and EMT-type cells in PDAC.

The Schizophrenia Proneness Instrument, Child and Youth version (SPI-CY): Practicability and discriminative validity

Background Basic symptom (BS) criteria have been suggested to complement ultra-high risk (UHR) criteria in the early detection of psychosis in adults and in children and adolescents. To account for potential developmental particularities and a different clustering of BS in children and adolescents, the Schizophrenia Proneness Instrument, Child and Youth version (SPI-CY) was developed. Aims The SPI-CY was evaluated for its practicability and discriminative validity. Method The SPI-CY was administered to 3 groups of children and adolescents (mean age 16; range=8–18; 61% male): 23 at-risk patients meeting UHR and/or BS criteria (AtRisk), 22 clinical controls (CC), and 19 children and adolescents from the general population (GPS) matched to AtRisk in age, gender, and education. We expected AtRisk to score highest on the SPI-CY, and GPS lowest. Results The groups differed significantly on all 4 SPI-CY subscales. Pairwise post-hoc comparisons confirmed our expectations for all subscales and, at least on a descriptive level, most items. Pairwise subscale differences indicated at least moderate group effects (r≥0.37) which were largest for Adynamia (0.52≤r≥0.70). Adynamia also performed excellent to outstanding in ROC analyses (0.813≤AUC≥0.981). Conclusion The SPI-CY could be a helpful tool for detecting and assessing BS in the psychosis spectrum in children and adolescents, by whom it was well received. Furthermore, its subscales possess good discriminative validity. However, these results require validation in a larger sample, and the psychosis-predictive ability of the subscales in different age groups, especially the role of Adynamia, will have to be explored in longitudinal studies.

The significance of at-risk symptoms for psychosis in children and adolescents

The early detection and treatment of people at risk for psychosis is currently regarded as a promising strategy in fighting the devastating consequences of psychotic disorders. Currently, the 2 most broadly used sets of at-risk criteria, that is, ultra-high risk (UHR) and basic symptom criteria, were developed mainly in adult samples. We review the data regarding the presence and relevance of at-risk symptoms for psychosis in children and adolescents. The few existing studies suggest that attenuated psychotic symptoms (APS) and brief limited intermittent psychotic symptoms (BLIPS) do have some clinical relevance in young adolescents from the general population. Nevertheless, their differentiation from atypical psychotic symptoms or an emerging schizotypal personality disorder, as well as their stability and predictive accuracy for psychosis, are still unclear. Further, standard interviews for UHR criteria do not define a minimum age for the assessment of APS and BLIPS or guidelines as to when and how to include information from parents. APS and basic symptoms may be predictive of conversion to psychosis in help-seeking young adolescents. Nevertheless, the rate and timing, and thus the required observation time, need further study. Moreover, no study has yet addressed the issue of how to treat children and adolescents presenting with at-risk symptoms and criteria. Further research is urgently needed to examine if current at-risk criteria and approaches have to be tailored to the special needs of children and adolescents. A preliminary rationale for how to deal with at-risk symptoms for psychosis in clinical practice is provided.

Comparing the prodrome of schizophrenia-spectrum psychoses and affective disorders with and without psychotic features

Following encouraging results in the early detection of psychotic disorders, interest in the early detection of affective, especially bipolar disorders, has recently been renewed. However, the differentiation between affective disorders with and without psychotic features is often missing, although it has been suggested that affective disorders with psychotic features may be distinct from those without psychotic features and closely linked to non-affective psychoses.

Basic symptoms and the prediction of first-episode psychosis

Recent focus on early detection and intervention in psychosis has renewed interest in subtle psychopathology beyond positive and negative symptoms. Such self-experienced sub-clinical disturbances are described in detail by the basic symptom concept. This review will give an introduction into the concept of basic symptoms and describe the development of the current instruments for their assessment, the Schizophrenia Proneness Instrument, Adult (SPI-A) and Child and Youth version (SPI-CY), as well as of the two at-risk criteria: the at-risk criterion Cognitive-Perceptive Basic Symptoms (COPER) and the high-risk criterion Cognitive Disturbances (COGDIS). Further, an overview of prospective studies using both or either basic symptom criteria and transition rates related to these will be given, and the potential benefit of combining ultra-high risk criteria, particularly attenuated psychotic symptoms, and basic symptom criteria will be discussed. Finally, their prevalence in psychosis patients, i.e. the sensitivity, as well as in general population samples will be described. It is concluded that both COPER and COGDIS are able to identify subjects at a high risk of developing psychosis. Further, they appear to be sufficiently frequent prior to onset of the first psychotic episode as well as sufficiently rare in persons of general population to be considered as valuable for an early detection of psychosis.

Rationale and first results of developing at-risk (prodromal) criteria for bipolar disorder

Bipolar affective disorder (BD) is a severe, recurrent and disabling disorder with devastating consequences for individuals, families and society. Although these hazards and costs provide a compelling rationale for development of early detection and early intervention strategies in BD, the development of at-risk criteria for first episode mania is still in an early stage of development. In this paper we review the literature with respect to the clinical, neuroantomical and neuropsychological data, which support this goal. We also describe our recently developed bipolar at-risk criteria (BAR). This criteria comprises the peak age range of the first onset of bipolar disorder, genetic risk, presenting with sub-threshold mania, cyclothymic features or depressive symptoms. An initial pilot evaluation of the BAR criteria in 22 subjects indicated conversion rates to proxies of first-episode mania of 23% within 265 days on average, and high specificity and sensitivity of the criteria. If prospective studies confirm the validity of the BAR criteria, then the criteria would have the potential to open up new avenues of research for indicated prevention in BD and might therefore offer opportunities to ameliorate the severity of, or even prevent BD.

Diagnostic microchip to assay 3D colony-growth potential of captured circulating tumor cells

Microfluidic technology has been successfully applied to isolate very rare tumor-derived epithelial cells (circulating tumor cells, CTCs) from blood with relatively high yield and purity, opening up exciting prospects for early detection of cancer. However, a major limitation of state-of-the-art CTC-chips is their inability to characterize the behavior and function of captured CTCs, for example to obtain information on proliferative and invasive properties or, ultimately, tumor re-initiating potential. Although CTCs can be efficiently immunostained with markers reporting phenotype or fate (e.g. apoptosis, proliferation), it has not yet been possible to reliably grow captured CTCs over long periods of time and at single cell level. It is challenging to remove CTCs from a microchip after capture, therefore such analyses should ideally be performed directly on-chip. To address this challenge, we merged CTC capture with three-dimensional (3D) tumor cell culture on the same microfluidic platform. PC3 prostate cancer cells were isolated from spiked blood on a transparent PDMS CTC-chip, encapsulated on-chip in a biomimetic hydrogel matrix (QGel™) that was formed in situ, and their clonal 3D spheroid growth potential was assessed by microscopy over one week in culture. The possibility to clonally expand a subset of captured CTCs in a near-physiological in vitro model adds an important element to the expanding CTC-chip toolbox that ultimately should improve prediction of treatment responses and disease progression.

Diffusion-weighted MR imaging in the head and neck

Extracranial applications of diffusion-weighted (DW) magnetic resonance (MR) imaging are gaining increasing importance, including in head and neck radiology. The main indications for performing DW imaging in this relatively small but challenging region of the body are tissue characterization, nodal staging, therapy monitoring, and early detection of treatment failure by differentiating recurrence from posttherapeutic changes. Lower apparent diffusion coefficients (ADCs) have been reported in the head and neck region of adults and children for most malignant lesions, as compared with ADCs of benign lesions. For nodal staging, DW imaging has shown promise in helping detect lymph node metastases, even in small (subcentimeter) nodes with lower ADCs, as compared with normal or reactive nodes. Follow-up of early response to treatment is reflected in an ADC increase in the primary tumor and nodal metastases; whereas nonresponding lesions tend to reveal only a slight increase or even a decrease in ADC during follow-up. Optimization and standardization of DW imaging technical parameters, comparison of DW images with morphologic images, and increasing experience, however, are prerequisites for successful application of this challenging technique in the evaluation of various head and neck pathologic conditions.

Technetium-99m-HDP uptake characteristics in equine fractures: a retrospective study

Bone scintigraphy is a very sensitive diagnostic tool to detect elevated bone metabolism. In cases of fractures and fissure fractures, the radiopharmaceutical uptake in the bone is said to be increased within a few hours after the injury. In this retrospective study, the scintigraphic uptake characteristics at the fracture site of 36 horses with radiographically confirmed fractures or fissure fractures were evaluated. Uptake ratios between the fracture region and adjacent normal bone or soft tissue activity respectively were calculated and compared to different anamnestic and radiographic data. The overall sensitivity of bone scintigraphy was 94.4% (34 positive cases out of 36). In the 36 horses, no correlation between the age of the fracture and the radiopharmaceutical uptake was found. However, there seems to be a lack of sensitivity in early detection of equine pelvic fractures when a standing bone scintigraphy examination protocol is used.

Accuracy of magnetic resonance imaging for the diagnosis of multiple sclerosis: systematic review

OBJECTIVE: To determine the accuracy of magnetic resonance imaging criteria for the early diagnosis of multiple sclerosis in patients with suspected disease. DESIGN: Systematic review. DATA SOURCES: 12 electronic databases, citation searches, and reference lists of included studies. Review methods Studies on accuracy of diagnosis that compared magnetic resonance imaging, or diagnostic criteria incorporating such imaging, to a reference standard for the diagnosis of multiple sclerosis. RESULTS: 29 studies (18 cohort studies, 11 other designs) were included. On average, studies of other designs (mainly diagnostic case-control studies) produced higher estimated diagnostic odds ratios than did cohort studies. Among 15 studies of higher methodological quality (cohort design, clinical follow-up as reference standard), those with longer follow-up produced higher estimates of specificity and lower estimates of sensitivity. Only two such studies followed patients for more than 10 years. Even in the presence of many lesions (> 10 or > 8), magnetic resonance imaging could not accurately rule multiple sclerosis in (likelihood ratio of a positive test result 3.0 and 2.0, respectively). Similarly, the absence of lesions was of limited utility in ruling out a diagnosis of multiple sclerosis (likelihood ratio of a negative test result 0.1 and 0.5). CONCLUSIONS: Many evaluations of the accuracy of magnetic resonance imaging for the early detection of multiple sclerosis have produced inflated estimates of test performance owing to methodological weaknesses. Use of magnetic resonance imaging to confirm multiple sclerosis on the basis of a single attack of neurological dysfunction may lead to over-diagnosis and over-treatment.

Point Process Methodology for On-line Spatio-temporal Disease Surveillance

The AEGISS (Ascertainment and Enhancement of Gastrointestinal Infection Surveillance and Statistics) project aims to use spatio-temporal statistical methods to identify anomalies in the space-time distribution of non-specific, gastrointestinal infections in the UK, using the Southampton area in southern England as a test-case. In this paper, we use the AEGISS project to illustrate how spatio-temporal point process methodology can be used in the development of a rapid-response, spatial surveillance system. Current surveillance of gastroenteric disease in the UK relies on general practitioners reporting cases of suspected food-poisoning through a statutory notification scheme, voluntary laboratory reports of the isolation of gastrointestinal pathogens and standard reports of general outbreaks of infectious intestinal disease by public health and environmental health authorities. However, most statutory notifications are made only after a laboratory reports the isolation of a gastrointestinal pathogen. As a result, detection is delayed and the ability to react to an emerging outbreak is reduced. For more detailed discussion, see Diggle et al. (2003). A new and potentially valuable source of data on the incidence of non-specific gastro-enteric infections in the UK is NHS Direct, a 24-hour phone-in clinical advice service. NHS Direct data are less likely than reports by general practitioners to suffer from spatially and temporally localized inconsistencies in reporting rates. Also, reporting delays by patients are likely to be reduced, as no appointments are needed. Against this, NHS Direct data sacrifice specificity. Each call to NHS Direct is classified only according to the general pattern of reported symptoms (Cooper et al, 2003). The current paper focuses on the use of spatio-temporal statistical analysis for early detection of unexplained variation in the spatio-temporal incidence of non-specific gastroenteric symptoms, as reported to NHS Direct. Section 2 describes our statistical formulation of this problem, the nature of the available data and our approach to predictive inference. Section 3 describes the stochastic model. Section 4 gives the results of fitting the model to NHS Direct data. Section 5 shows how the model is used for spatio-temporal prediction. The paper concludes with a short discussion.

Monotone Constrained Tensor-product B-spline with application to screening studies

When different markers are responsive to different aspects of a disease, combination of multiple markers could provide a better screening test for early detection. It is also resonable to assume that the risk of disease changes smoothly as the biomarker values change and the change in risk is monotone with respect to each biomarker. In this paper, we propose a boundary constrained tensor-product B-spline method to estimate the risk of disease by maximizing a penalized likelihood. To choose the optimal amount of smoothing, two scores are proposed which are extensions of the GCV score (O'Sullivan et al. (1986)) and the GACV score (Ziang and Wahba (1996)) to incorporate linear constraints. Simulation studies are carried out to investigate the performance of the proposed estimator and the selection scores. In addidtion, sensitivities and specificities based ona pproximate leave-one-out estimates are proposed to generate more realisitc ROC curves. Data from a pancreatic cancer study is used for illustration.