Neuroblastoma stage 4S: Tumor regression rate and risk factors of progressive disease

Background: The clinical course of neuroblastoma stage 4S or MS is characterized by a high rate of spontaneous tumor regression and favorable outcome. However, the clinical course and rate of the regression are poorly understood. Methods: A retrospective cohort study was performed, including all patients with stage 4S neuroblastoma without MYCN amplification, from two Dutch centers between 1972 and 2012. We investigated the clinical characteristics, the biochemical activity reflected in urinary catecholamine excretion, and radiological imaging to describe the kinetics of tumor regression, therapy response and outcome. Results: The cohort of 31 patients reached a 10-year overall survival of 84% ± 7% (median follow-up 16 years; range, 3.3-39). During the regressive phase, liver size normalized in 91% of the patients and catecholamine excretion in 83%, both after a median of two months (liver size: range, 0-131; catecholamines: range, 0-158). The primary tumors completely regressed in 69% after 13 months (range, 6-73), and the liver architecture normaliz

Child abuse and neglect in paediatric burns: The majority is caused by neglect and thus preventable

Introduction: It is complex to distinguish negligent burns from inflicted and non-intentional burns, especially since no deliberate action caused the burn. Its recognition is important to create a safe life without (future) burns for our loved-ones who cannot take care of themselves (yet). Our aim was to investigate the incidence and associated characteristics of negligent burns are among children treated at a burn center. Methods: We retrospectively reviewed medical files of all children attending a Dutch burn center with an acute burn between January 2013–December 2015. The conclusion of the Child Abuse and Neglect team (CAN) was used to define inflicted, negligent or non-intentional burns. The remaining cases were reviewed by an expert panel using a standardized protocol. Demographic and social data as well as clinical information about the burn were collected. Results: In total 330 children were included. Negligent burns accounted for 56%, non-intentional for 42% and inflicted for 2% of the burns. Negligent burns were associated with: hot beverages (OR 4.40, 95%CI 2.75–7.05), a younger age (p < 0.001), occurrence at home (OR 4.87 95%CI 2.80–8.45) and were located at the anterior trunk (OR 2.75, 95%CI 1.73–4.35) and neck (OR 1.98, 95%CI 1.12–3.50). Conclusion: This study shows that neglect is a major factor in the occurrence of burns in young children, therefore we conclude that the majority of paediatric burns are preventable. Educational programs creating awareness and focussing on prevention of these burns should be aimed at households, since the majority of negligent as cause of preventable burns occur at home

Neuroblastoma stage 4S: Tumor regression rate and risk factors of progressive disease

BACKGROUND: The clinical course of neuroblastoma stage 4S or MS is characterized by a high rate of spontaneous tumor regression and favorable outcome. However, the clinical course and rate of the regression are poorly understood. METHODS: A retrospective cohort study was performed, including all patients with stage 4S neuroblastoma without MYCN amplification, from two Dutch centers between 1972 and 2012. We investigated the clinical characteristics, the biochemical activity reflected in urinary catecholamine excretion, and radiological imaging to describe the kinetics of tumor regression, therapy response and outcome. RESULTS: The cohort of 31 patients reached a 10-year overall survival of 84% ± 7% (median follow-up 16 years; range, 3.3-39). During the regressive phase, liver size normalized in 91% of the patients and catecholamine excretion in 83%, both after a median of two months (liver size: range, 0-131; catecholamines: range, 0-158). The primary tumors completely regressed in 69% after 13 months (range, 6-73), and the liver architecture normalized in 52% after 15 months (range, 5-131). Antitumor treatment was given in 52% of the patients. Interestingly, regression rates were similar for treated and untreated patients. Four of seven patients < 4 weeks old died of rapid liver expansion and organ compression. Three patients progressed to stage 4, 3 to 13 months after diagnosis; all had persistently elevated catecholamines. CONCLUSION: Patients < 4 weeks old with neuroblastoma stage 4S are at risk of fatal outcome caused by progression of liver metastases. In other patients, tumor regression is characterized by a rapid biochemical normalization that precedes radiological regression

Neuroblastoma stage 4S: Tumor regression rate and risk factors of progressive disease

Background: The clinical course of neuroblastoma stage 4S or MS is characterized by a high rate of spontaneous tumor regression and favorable outcome. However, the clinical course and rate of the regression are poorly understood. Methods: A retrospective cohort study was performed, including all patients with stage 4S neuroblastoma without MYCN amplification, from two Dutch centers between 1972 and 2012. We investigated the clinical characteristics, the biochemical activity reflected in urinary catecholamine excretion, and radiological imaging to describe the kinetics of tumor regression, therapy response and outcome. Results: The cohort of 31 patients reached a 10-year overall survival of 84% ± 7% (median follow-up 16 years; range, 3.3-39). During the regressive phase, liver size normalized in 91% of the patients and catecholamine excretion in 83%, both after a median of two months (liver size: range, 0-131; catecholamines: range, 0-158). The primary tumors completely regressed in 69% after 13 months (range, 6-73), and the liver architecture normalized in 52% after 15 months (range, 5-131). Antitumor treatment was given in 52% of the patients. Interestingly, regression rates were similar for treated and untreated patients. Four of seven patients < 4 weeks old died of rapid liver expansion and organ compression. Three patients progressed to stage 4, 3 to 13 months after diagnosis; all had persistently elevated catecholamines. Conclusion: Patients < 4 weeks old with neuroblastoma stage 4S are at risk of fatal outcome caused by progression of liver metastases. In other patients, tumor regression is characterized by a rapid biochemical normalization that precedes radiological regression

Multi-frequency radar remote sensing of sea ice. Modelling and interpretation of polarimetric multi-frequency radar signatures of sea ice

This thesis deals with polarimetric multi-frequency radar signatures of sea ice. It presents a thorough background on the topic and three case studies. The first study presents a global sensitivity analysis of the fully polarimetric radar backscatter response from snow covered sea ice. The analysis is global in the sense that it takes into account the observed ranges of sea ice properties that are needed as input, and it attributes a quantitative sensitivity measure to each individual input parameter, such that the most influential one(s) can be identified. Generally it can be concluded that parameters describing roughness of interfaces and dimensions of brine inclusions and snow grains, are more important than parameters describing bulk properties such as salinity, temperature and density. The second study complements the sensitivity analysis by showing that the considered backscatter model compare well to SAR data at both C- and L-band, for ice identified as lead ice and ice floes (which presumably is first year ice). Generally, C-band data compare better than L-band data. Likewise, the ice identified as ice floes is better represented than ice types identified as lead ice. The model primarily deviates from the data in the co-polarised phase difference and the cross-polarised channel. The third study focuses on the backscatter from frazil and grease ice. A model for the dispersion relation of gravity waves in viscous ice slicks is considered and linked to a band ratio. This ratio provides the backscatter relative to a reference radar frequency and can readily be compared to data. The analysis concludes that under certain conditions, ice slicks have strong impact on the spectral behaviour of the radar backscatter. According to the numerical simulation, the damping due to ice slicks is strong at wavelengths relevant to radar remote sensing