Expected impact of MRI-related interreader variability on ProScreen prostate cancer screening trial: a pre-trial validation study.

BACKGROUND: The aim of this study is to investigate the potential impact of prostate magnetic resonance imaging (MRI) -related interreader variability on a population-based randomized prostate cancer screening trial (ProScreen). METHODS: From January 2014 to January 2018, 100 men aged 50-63 years with clinical suspicion of prostate cancer (PCa) in Helsinki University Hospital underwent MRI. Nine radiologists individually reviewed the pseudonymized MRI scans of all 100 men in two ProScreen trial centers. All 100 men were biopsied according to a histological composite variable comprising radical prostatectomy histology (N = 38) or biopsy result within 1 year from the imaging (N = 62). Fleiss' kappa (κ) was used to estimate the combined agreement between all individual radiologists. Sample data were subsequently extrapolated to 1000-men subgroups of the ProScreen cohort. RESULTS: Altogether 89% men of the 100-men sample were diagnosed with PCa within a median of 2.4 years of follow-up. Clinically significant PCa (csPCa) was identified in 76% men. For all PCa, mean sensitivity was 79% (SD ±10%, range 62-96%), and mean specificity 60% (SD ±22%, range 27-82%). For csPCa (Gleason Grade 2-5) MRI was equally sensitive (mean 82%, SD ±9%, range 67-97%) but less specific (mean 47%, SD ±20%, range 21-75%). Interreader agreement for any lesion was fair (κ 0.40) and for PI-RADS 4-5 lesions it was moderate (κ 0.60). Upon extrapolating these data, the average sensitivity and specificity to a screening positive subgroup of 1000 men from ProScreen with a 30% prevalence of csPCa, 639 would be biopsied. Of these, 244 men would be true positive, and 395 false positive. Moreover, 361 men would not be referred to biopsy and among these, 56 csPCas would be missed. The variation among the radiologists was broad as the least sensitive radiologist would have twice as many men biopsied and almost three times more men would undergo unnecessary biopsies. Although the most sensitive radiologist would miss only 2.6% of csPCa (false negatives), the least sensitive radiologist would miss every third. CONCLUSIONS: Interreader agreement was fair to moderate. The role of MRI in the ongoing ProScreen trial is crucial and has a substantial impact on the screening process.

Asthma as aetiology of bronchiectasis in Finland.

BACKGROUND: By definition bronchiectasis (BE) means destructed structure of normal bronchus as a consequence of frequent bacterial infections and inflammation. In many senses, BE is a neglected orphan disease. A recent pan-European registry study, EMBARC, has been set up in order to better understand its pathophysiology, better phenotype patients, and to individualize their management. AIM: To examine the aetiology and co-morbidity of BE in the capital area in Finland. METHODS: Two hundred five patients with BE diagnosis and follow up visits between 2016 and 2017 in Helsinki University Hospital were invited to participate in the study. Baseline demographics, lung functions, imaging, microbiological, and therapeutic data, together with co-morbidities were entered into EMBARC database. Clinical characteristics, aetiologic factors, co-morbidities, and risk factors for extensive BE were explored. RESULTS: To the study included 95 adult patients and seventy nine percent of the BE patients were women. The mean age was 69 years (SD ±â€¯13). Asthma was a comorbid condition in 68% of the patients but in 26% it was estimated to be the cause of BE. Asthma was aetiological factor for BE if it had been diagnosed earlier than BE. As 41% BE were idiopathic, in 11% the disorder was postinfectious and others were associated to rheumatic disease, Alpha-1-antitrypsin deficiency, IgG deficiency and Kartagener syndrome. The most common co-morbidities in addition to asthma were cardiovascular disease (30%), gastroesophageal reflux disease (26%), overweight (22%), diabetes (16%), inactive neoplasia (15%), and immunodeficiency (12%). Extensive BE was found in 68% of BE patients in whom four or more lobes were affected. Risk factors for extensive BE were asthma (OR 2.7), asthma as aetiology for BE (OR 4.3), and rhinosinusitis (OR 3.1). CONCLUSIONS: Asthma was associated to BE in 68% and it was estimated as aetiology in every fourth patient. However, retrospectively, it is difficult to exclude asthma as a background cause in patients with asthma-like symptoms and respiratory infections. We propose asthma as an aetiology factor for BE if it is diagnosed earlier than BE. Asthma and rhinosinusitis were predictive for extensive BE.

Simultaneous Comparison of Two Roller Compaction Techniques and Two Particle Size Analysis Methods.

A new dry granulation technique, gas-assisted roller compaction (GARC), was compared with conventional roller compaction (CRC) by manufacturing 34 granulation batches. The process variables studied were roll pressure, roll speed, and sieve size of the conical mill. The main quality attributes measured were granule size and flow characteristics. Within granulations also the real applicability of two particle size analysis techniques, sieve analysis (SA) and fast imaging technique (Flashsizer, FS), was tested. All granules obtained were acceptable. In general, the particle size of GARC granules was slightly larger than that of CRC granules. In addition, the GARC granules had better flowability. For example, the tablet weight variation of GARC granules was close to 2%, indicating good flowing and packing characteristics. The comparison of the two particle size analysis techniques showed that SA was more accurate in determining wide and bimodal size distributions while FS showed narrower and mono-modal distributions. However, both techniques gave good estimates for mean granule sizes. Overall, SA was a time-consuming but accurate technique that provided reliable information for the entire granule size distribution. By contrast, FS oversimplified the shape of the size distribution, but nevertheless yielded acceptable estimates for mean particle size. In general, FS was two to three orders of magnitude faster than SA.

Transport of particle-associated elements in two agriculture-dominated boreal river systems.

Transport of particulate pollutants in fluvial systems can contribute greatly to total loads. Understanding transport mechanics under different hydrological conditions is key in successful load estimation. This study analysed trace elements and physico-chemical parameters in time-integrated suspended sediment samples, together with dissolved and total concentrations of pollutants, along two agriculture- and peatland-dominated boreal river systems. The samples were taken in a spatially and temporally comprehensive sampling programme during the ice-free seasons of 2010 and 2011. The hydrochemistry and transport of particle-bound elements in the rivers were strongly linked to intense land use and acid sulphate soils in the catchment area, with arable, pasture and peat areas in particular being main diffuse sources. There were significant seasonal and temporal variations in dissolved and particulate fluxes, but spatial variations were small. Continuous measurements of EC, turbidity and discharge proved to be an accurate indicator of dissolved and particulate fluxes. Overall, the results show that transport of particle-bound elements makes a major contribution to total transport fluxes in agriculture-dominated boreal rivers.

Past and future seasonal variation in pH and metal concentrations in runoff from river basins on acid sulphate soils in Western Finland.

Drainage of acid sulphate soils (ASS) increases oxidation, leading to extensive leaching of acidity and metals to rivers (Al, Cd, Cr, Fe, Ni and Zn). This is often apparent during high runoff periods in spring and autumn after long dry periods with low groundwater levels and associated ASS oxidation. Regression models were used to study changes in these water quality variables according to various discharge scenarios. The knowledge of seasonal patterns of water quality variables in future is important for planning land use of the catchments in relation to WFD of European Union. The data showed that river water acidity (pH and metals) increased with discharge, with the correlation being strongest in low runoff periods in winter and summer and less clear in spring. With future climate change, river acidity can increase radically, especially during winters following extremely dry summers, and pH and metal peaks may occur even during winter.

Long-term trends and variation of acidity, COD(Mn) and colour in coastal rivers of Western Finland in relation to climate and hydrology.

High acidity caused by geochemical processes and intensive land use of acid sulphate (AS) soils have continuously degraded the status of water bodies in Western Finland. Despite this, research on the long-term pattern and dynamics of acidification in rivers affected by acid sulphate soils is scarce. This study examined changes in alkalinity and pH value during the period 1913-2007 in nine large Finnish rivers discharging into the Gulf of Bothnia. In addition, patterns of COD(Mn) and colour were analysed during the period 1961-2007. Relationships between pH, alkalinity, COD(Mn) and colour and climate variables were also studied. In four rivers with no AS soil impact (Kokemäenjoki, Kemijoki, Iijoki and Oulujoki), critically low pH levels did not occur during the study period, whereas three rivers exposed to minor or moderate levels of runoff from AS soils (Lestijoki, Kalajoki, and Siikajoki) had all periods with critically low pH and alkalinity. The most severe acidity problems occurred in the rivers Kyrönjoki and Lapuanjoki, with extensive drainage of AS soils being the main reason for the low pH status. Maximum discharge was clearly related to the acidity status of many rivers during the autumn-winter runoff period, when a significant negative linear correlation was found between maximum discharge and minimum pH in the rivers affected by AS soils. There was also a more distinct relationship between maximum chemical oxygen demand (COD(Mn)) and minimum pH in autumn runoff than in spring. COD(Mn) levels significantly increased with increasing discharge in the rivers with no or minor AS soil impact. Climate change is predicted to increase river flow in general and winter discharge in particular, and therefore the acidity problems in affected rivers may increase in a future climate.

Non-Hodgkin lymphoma response evaluation with MRI texture classification.

BACKGROUND: To show magnetic resonance imaging (MRI) texture appearance change in non-Hodgkin lymphoma (NHL) during treatment with response controlled by quantitative volume analysis. METHODS: A total of 19 patients having NHL with an evaluable lymphoma lesion were scanned at three imaging timepoints with 1.5T device during clinical treatment evaluation. Texture characteristics of images were analyzed and classified with MaZda application and statistical tests. RESULTS: NHL tissue MRI texture imaged before treatment and under chemotherapy was classified within several subgroups, showing best discrimination with 96% correct classification in non-linear discriminant analysis of T2-weighted images.Texture parameters of MRI data were successfully tested with statistical tests to assess the impact of the separability of the parameters in evaluating chemotherapy response in lymphoma tissue. CONCLUSION: Texture characteristics of MRI data were classified successfully; this proved texture analysis to be potential quantitative means of representing lymphoma tissue changes during chemotherapy response monitoring.