An Isotropic Light Sensor for Measurements of Visible Actinic Flux in Clouds

A low-cost isotropic light sensor is described consisting of a spherical diffuser connected to a single photodiode by a light conductor. The directional response to light is isotropic to a high degree. The small, lightweight, and rugged construction makes this instrument suitable not only for application on aircraft or under balloons but also on the ground in microclimatological studies. A vertical profile of actinic flux in the visible range (400-750 nm) in Arctic stratus, obtained with this instrument under a tethered balloon during the FIRE experiment in 1998, is presented

Impact of age, tumor characteristics, and treatment on local control and disease outcome in early stage breat cancer : an EORTC translational research project

Dit proefschrift behelst een aantal klinische studies met betrekking tot de behandeling van borstkanker. Zowel aspecten van de locoregionale behandeling, d.w.z. chirurgie en bestraling, als van de systemische behandeling, d.w.z. chemotherapie en hormonale therapie, worden belicht. Het proefschrift bestaat uit drie delen. Het eerste deel behelst de rol van de timing van chemotherapie t.o.v. de operatie bij de behandeling van borstkanker. Hieruit blijkt onder meer dat het geven van chemotherapie voorafgaand aan de operatie leidt tot "krimpen" van het gezwel en derhalve tot een stijging in het aantal borstsparende behandelingen. In deel twee wordt de rol van de locoregionale behandeling, d.w.z. chirurgie en bestraling, bij borstkanker bestudeerd. Tevens worden potenti_le voorspellende factoren voor het optreden van een lokaal recidief bestudeerd. Met name jonge vrouwen die borstsparende therapie ondergaan blijken een verhoogd risico te hebben op het optreden van een lokaal recidief. Het optreden van het lokale recidief lijkt voorspeld te kunnen worden door overexpressie van de tumorcel marker, genaamd PS6K. In deel drie wordt dieper ingegaan op vrouwen jonger dan veertig jaar met borstkanker. Deze groep vrouwen heeft een slechte prognose vergeleken met oudere vrouwen en de oorzaak hiervoor is onduidelijk. Derhalve wordt op dit moment geadviseerd om iedere vrouw jonger dan 35 jaar met borstkanker te behandelen met chemotherapie. In deel 3 wordt aangetoond dat er wel degelijk jonge vrouwen te identificeren zijn met een goede prognose waarbij de vraag gesteld kan worden of het geven van chemotherapie bij deze vrouwen wel noodzakelijk is.LEI Universiteit LeidenChirurgische oncologi

Dysautonomie bij konijnen

Dysautonomie is een storing of beschadiging van het autonome zenuwstelsel. Dit zijn de zenuwen voor de onwillekeurige lichaamsfuncties b.v. de hartslag, de beweging van de darm, de sluiting van de urineblaas, de ademhaling, het speekselen en sommige refl

Surface and Tethered-Balloon Observations of Actinic Flux: Effects of Arctic stratus, Surface Albedo and Solar Zenith Angle

As part of the FIRE III (First ISCCP Regional Experiment) Arctic Cloud Experiment actinic flux measurements were made above the Arctic Sea ice during May 1998. FIRE III was designed to address questions concerning clouds, radiation and chemistry in the Arctic sea ice region. The actinic flux, which is also referred to as the 4p-radiative flux, is the relevant radiative parameter needed to determine photodissociation rates. Moreover, it is discussed that the actinic flux may be used to determine vertical absorption profiles of the net irradiance, provided that the single scattering albedo is known. The diurnal cycle of UV-A (wavelength about 365 nm) and visible (wavelength about 550 nm) actinic fluxes during clear and cloudy conditions was measured by two 4p- radiometers installed just above the ice surface. In addition, vertical profiles of the visible actinic flux through low arctic stratus clouds were observed by means of a tethered balloon. The cloud thermodynamic and microphysical structure was assessed from observations made by the NCAR C-130 aircraft. The liquid water path was retrieved by a microwave radiometer. During clear skies the diurnal variation of the actinic flux was controlled mainly by Rayleigh scattering. Above the cloud layer the actinic flux was found to be almost the same as during clear sky conditions. This could be attributed to the fact that the effective albedo of the arctic sea ice and the cloud is only slightly higher than the ground albedo alone. The observed vertical actinic flux profiles in arctic stratus are discussed and compared with similar measurements made in Atlantic stratocumulus. In the arctic stratus clouds the actinic flux was found to be nearly constant with height, except in a shallow layer near the cloud top where the actinic flux significantly increased with height. The role of the solar zenith angle and ground albedo on in-cloud actinic flux profiles is discussed. It is concluded that the observed strong increase of the actinic flux in the upper part of the arctic stratus layer is a typical feature associated with large solar zenith angles

The impact of loco-regional recurrences on metastatic progression in early-stage breast cancer: a multistate model

To study whether the effects of prognostic factors associated with the occurrence of distant metastases (DM) at primary diagnosis change after the incidence of loco-regional recurrences (LRR) among women treated for invasive stage I or II breast cancer. The study population consisted of 3,601 women, enrolled in EORTC trials 10801, 10854, or 10902 treated for early-stage breast cancer. Data were analysed in a multivariate, multistate model by using multivariate Cox regression models, including a state-dependent covariate. The presence of a LRR in itself is a significant prognostic risk factor (HR: 3.64; 95%-CI: 2.02-6.5) for the occurrence of DM. Main prognostic risk factors for a DM are young age at diagnosis (</=40: HR: 1.79; 95%-CI: 1.28-2.51), larger tumour size (HR: 1.58; 95%-CI: 1.35-1.84) and node positivity (HR: 2.00; 95%-CI: 1.74-2.30). Adjuvant chemotherapy is protective for a DM (HR: 0.66; 95%-CI: 0.55-0.80). After the occurrence of a LRR the latter protective effect has disappeared (P = 0.009). The presence of LRR in itself is a significant risk factor for DM. For patients who are at risk of developing LRR, effective local control should be the main target of therapy

Examiners’ perceptions in surgical education: the blind spot in the assessment of OSCEs

Surgical oncolog

The ESSO core curriculum committee update on surgical oncology

Cancer care; Curriculum; Surgical oncologyCuidado del cancer; Plan de estudios; Oncología quirúrgicaCura del càncer; Pla d'estudis; Oncologia quirúrgicaIntroduction Surgical oncology is a defined specialty within the European Board of Surgery within the European Union of Medical Specialists (UEMS). Variation in training and specialization still occurs across Europe. There is a need to align the core knowledge needed to fulfil the criteria across subspecialities in surgical oncology. Material and methods The core curriculum, established in 2013, was developed with contributions from expert advisors from within the European Society of Surgical Oncology (ESSO), European Society for Radiotherapy and Oncology (ESTRO) and European Society of Medical Oncology (ESMO) and related subspeciality experts. Results The current version reiterates and updates the core curriculum structure needed for current and future candidates who plans to train for and eventually sit the European fellowship exam for the European Board of Surgery in Surgical Oncology. The content included is not intended to be exhaustive but, rather to give the candidate an idea of expectations and areas for in depth study, in addition to the practical requirements. The five elements included are: Basic principles of oncology; Disease site specific oncology; Generic clinical skills; Training recommendations, and, lastly; Eligibility for the EBSQ exam in Surgical Oncology. Conclusions As evidence-based care for cancer patients evolves through research into basic science, translational research and clinical trials, the core curriculum will evolve, mature and adapt to deliver continual improvements in cancer outcomes for patients

Impact of established prognostic factors and molecular subtype in very young breast cancer patients: pooled analysis of four EORTC randomized controlled trials

Young age at the time of diagnosis of breast cancer is an independent factor of poor prognosis. In many treatment guidelines, the recommendation is to treat young patients with adjuvant chemotherapy regardless of tumor characteristics. However, limited data on prognostic factors are available for young breast cancer patients. The purpose of this study was to determine the prognostic value of established clinical and pathological prognostic factors in young breast cancer patients. Data from four European Organisation for Research and Treatment of Cancer (EORTC) clinical trials were pooled, resulting in a dataset consisting of 9,938 early breast cancer patients with a median follow-up of 11 years. For 549 patients aged less than 40 years at the time of diagnosis, including 341 node negative patients who did not receive chemotherapy, paraffin tumor blocks were processed for immunohistochemistry using a tissue microarray. Cox proportional hazard analysis was applied to assess the association of clinical and pathological factors with overall and distant metastasis free survival. For young patients, tumor size (P = 0.01), nodal status (P = 0.006) and molecular subtype (P = 0.02) were independent prognostic factors for overall survival. In the node negative subgroup, only molecular subtype was a prognostic factor for overall survival (P = 0.02). Young node negative patients bearing luminal A tumors had an overall survival rate of 94% at 10 years' follow-up compared to 72% for patients with basal-type tumors. Molecular subtype is a strong independent prognostic factor in breast cancer patients younger than 40 years of age. These data support the use of established prognostic factors as a diagnostic tool to assess disease outcome and to plan systemic treatment strategies in young breast cancer patient

Efficacy of adjuvant chemotherapy according to hormone receptor status in young patients with breast cancer: a pooled analysis

Introduction Breast cancer at a young age is associated with an unfavorable prognosis. Very young patients with breast cancer therefore are advised to undergo adjuvant chemotherapy irrespective of tumor stage or grade. However, chemotherapy alone may not be adequate in young patients with hormone receptor-positive breast cancer. Therefore, we studied the effect of adjuvant chemotherapy in young patients with breast cancer in relation to hormone receptor status. Methods Paraffin-embedded tumor material was collected from 480 early-stage breast cancer patients younger than 41 years who participated in one of four European Organization for Research and Treatment of Cancer trials. Using immunohistochemistry on the whole series of tumors, we assessed estrogen receptor (ER) status and progesterone receptor (PgR) status in a standardized way. Endpoints in this study were overall survival (OS) and distant metastasis-free survival (DMFS). The median follow-up period was 7.3 years. Results Overall, patients with ER-positive tumors had better OS rates (hazard ratio [HR] 0.63; P = 0.02) compared with those with ER-negative tumors. However, in the subgroup of patients who received chemotherapy, no significant difference in OS (HR 0.87; P = 0.63) and DMFS (HR 1.36; P = 0.23) was found between patients with ER-positive tumors or those with ER-negative tumors. These differences were similar for PgR status. Conclusion Young patients with hormone receptor-positive tumors benefit less from adjuvant systemic chemotherapy than patients with hormone receptor-negative tumors. These results confirm that chemotherapy alone cannot be considered optimal adjuvant systemic treatment in breast cancer patients 40 years old or younger with hormone receptor-positive tumors

Anti-Melanoma immunity and local regression of cutaneous metastases in melanoma patients treated with monobenzone and imiquimod; a phase 2 a trial

Vitiligo development in melanoma patients during immunotherapy is a favorable prognostic sign and indicates breakage of tolerance against melanocytic/melanoma antigens. We investigated a novel immunotherapeutic approach of the skin-depigmenting compound monobenzone synergizing with imiquimod in inducing antimelanoma immunity and melanoma regression. Stage III-IV melanoma patients with non-resectable cutaneous melanoma metastases were treated with monobenzone and imiquimod (MI) therapy applied locally to cutaneous metastases and adjacent skin during 12 weeks, or longer. Twenty-one of 25 enrolled patients were evaluable for clinical assessment at 12 weeks. MI therapy was well-tolerated. Partial regression of cutaneous metastases was observed in 8 patients and stable disease in 1 patient, reaching the statistical endpoint of treatment efficacy. Continued treatment induced clinical response in 11 patients, including complete responses in three patients. Seven patients developed vitiligo-like depigmentation on areas of skin that were not treated with MI therapy, indicating a systemic effect of MI therapy. Melanoma-specific antibody responses were induced in 7 of 17 patients tested and melanoma-specific CD8+T-cell responses in 11 of 15 patients tested. These systemic immune responses were significantly increased during therapy as compared to baseline in responding patients. This study shows that MI therapy induces local and systemic anti-melanoma immunity and local regression of cutaneous metastases in 38% of patients, or 52% during prolonged therapy. This study provides proof-of-concept of MI therapy, a low-cost, broadly applicable and well-tolerated treatment for cutaneous melanoma metastases, attractive for further clinical investigation