Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Tine Bjørn Nielsen is active.

Publication


Featured researches published by Tine Bjørn Nielsen.


Acta Oncologica | 2014

Pattern of loco-regional failure after definitive radiotherapy for non-small cell lung cancer

Tine Schytte; Tine Bjørn Nielsen; Carsten Brink; Olfred Hansen

Abstract Non-small cell lung cancer (NSCLC) is associated with poor survival even though patients are treated with curatively intended radiotherapy. Survival is affected negatively by lack of loco-regional tumour control, but survival is also influenced by comorbidity caused by age and smoking, and occurrence of distant metastasis. It is challenging to evaluate loco-regional control after definitive radiotherapy for NSCLC since it is difficult to distinguish between radiation-induced damage to the lung tissue and tumour progression/recurrence. In addition it may be useful to distinguish between intrapulmonary failure and mediastinal failure to be able to optimize radiotherapy in order to improve loco-regional control even though it is not easy to discriminate between the two sites of failure. Material and methods. This study is a retrospective analysis of 331 NSCLC patients treated with definitive radiotherapy from 2002 to 2011. The patients were treated consecutively at the Department of Oncology, Odense University Hospital, Denmark with at least 60 Gy. All patients were followed in a planned follow-up schedule and no patients were lost for follow-up. Results. At the time of the analysis 93 patients had loco-regional failure only. Of these patients, 68 had intrapulmonary failure only, one patient had failure in mediastinum only, and 24 patients had intrapulmonary failure as well as mediastinal failure. Of the patients which had lung failure only, 78% had mediastinal involvement at treatment start. The only covariate with significant impact on developing intrapulmonary failure only was gross tumour volume. Median survival for the total group of 331 patients was 19 months. The median survival for patients with intrapulmonary failure only was 19 months, and it was 20 months for the patients with mediastinal relapse. Conclusion. We conclude that focus should be on increasing doses to intrapulmonary tumour volume, when dose escalation is applied to improve local tumour control in NSCLC patients treated with definitive radiotherapy, since most recurrences are located here.


Medical Physics | 2011

Influence of dose calculation algorithms on the predicted dose distributions and NTCP values for NSCLC patients

Tine Bjørn Nielsen; Elinore Wieslander; Antonella Fogliata; Morten Nielsen; O. Hansen; Carsten Brink

PURPOSE To investigate differences in calculated doses and normal tissue complication probability (NTCP) values between different dose algorithms. METHODS Six dose algorithms from four different treatment planning systems were investigated: Eclipse AAA, Oncentra MasterPlan Collapsed Cone and Pencil Beam, Pinnacle Collapsed Cone and XiO Multigrid Superposition, and Fast Fourier Transform Convolution. Twenty NSCLC patients treated in the period 2001-2006 at the same accelerator were included and the accelerator used for treatments were modeled in the different systems. The treatment plans were recalculated with the same number of monitor units and beam arrangements across the dose algorithms. Dose volume histograms of the GTV, PTV, combined lungs (excluding the GTV), and heart were exported and evaluated. NTCP values for heart and lungs were calculated using the relative seriality model and the LKB model, respectively. Furthermore, NTCP for the lungs were calculated from two different model parameter sets. Calculations and evaluations were performed both including and excluding density corrections. RESULTS There are found statistical significant differences between the calculated dose to heart, lung, and targets across the algorithms. Mean lung dose and V20 are not very sensitive to change between the investigated dose calculation algorithms. However, the different dose levels for the PTV averaged over the patient population are varying up to 11%. The predicted NTCP values for pneumonitis vary between 0.20 and 0.24 or 0.35 and 0.48 across the investigated dose algorithms depending on the chosen model parameter set. The influence of the use of density correction in the dose calculation on the predicted NTCP values depends on the specific dose calculation algorithm and the model parameter set. For fixed values of these, the changes in NTCP can be up to 45%. CONCLUSIONS Calculated NTCP values for pneumonitis are more sensitive to the choice of algorithm than mean lung dose and V20 which are also commonly used for plan evaluation. The NTCP values for heart complication are, in this study, not very sensitive to the choice of algorithm. Dose calculations based on density corrections result in quite different NTCP values than calculations without density corrections. It is therefore important when working with NTCP planning to use NTCP parameter values based on calculations and treatments similar to those for which the NTCP is of interest.


Radiotherapy and Oncology | 2012

A dual centre study of setup accuracy for thoracic patients based on Cone-Beam CT data

Tine Bjørn Nielsen; Vibeke N. Hansen; Jonas Westberg; O. Hansen; Carsten Brink

BACKGROUND AND PURPOSE To compare setup uncertainties at two different institutions by using identical imaging and analysis techniques for thoracic patients with different fixation equipments. METHODS AND MATERIALS Patient registration results from Cone-Beam CT (CBCT) scans of 174 patients were evaluated (1068 CBCT scans). Patients were fixated using a standard or custom made fixation at Royal Marsden Hospital and Odense University Hospital, respectively. Five imaging protocols were retrospectively simulated to compare the fixation equipments. Systematic and random setup uncertainties were calculated to estimate sufficient treatment margins. RESULTS The setup uncertainties are of similar sizes at the two institutions and there is no observable drift in the precision of the fixation equipments during the treatment course. When a correcting imaging protocol is performed there is a significant increase of the systematic setup uncertainties in between imaging fractions. A margin reduction of ≥0.2 cm can be achieved for patients with peak-to-peak respiration amplitudes of ≥1.2 cm when changing from 4D-CT to Active Breathing Coordinator™ (ABC). CONCLUSIONS The setup uncertainties at the two institutions are the same despite different fixation equipments. Hence margins cannot be reduced by changing fixating equipment.


Acta Oncologica | 2014

Inhomogeneous dose escalation increases expected local control for NSCLC patients with lymph node involvement without increased mean lung dose.

Tine Bjørn Nielsen; Olfred Hansen; Tine Schytte; Carsten Brink

Abstract Background. Higher doses to NSCLC tumours are required to increase the low control rates obtained with conventional dose prescriptions. This study presents the concept of inhomogeneous dose distributions as a general way to increase local control probability, not only for isolated lung tumours but also for patients with involved lymph nodes. Material and methods. Highly modulated IMRT plans with homogeneous dose distributions with a prescribed dose of 66Gy/33F were created for 20 NSCLC patients, staged T1b-T4 N0-N3, using standard PTV dose coverage of 95–107%. For each patient, an inhomogeneous dose distribution was created with dose constraints of: PTV-coverage ≥ 95%, same mean lung dose as obtained in the homogeneous dose plan, maximum doses of 45 and 66 Gy to spinal canal and oesophagus, respectively, and V74Gy < 1 cm3 for each of: aorta, trachea + bronchi, the connective tissue in mediastinum, and the thorax wall. The dose was escalated using a TCP model implemented into the planning system. The difference in TCP values between the homogeneous and inhomogeneous plans were evaluated using two different TCP models. Results. Dose escalation was possible for all patients. TCP values based on assumed homogeneous distribution of clonogenic cells either in the GTV, CTV or PTV showed absolute TCP increases of approximately 15, 10 and 5 percentage points, respectively. This increase in local control was obtained without increasing the mean lung dose. However, small increases in maximum doses to the mediastinum were observed: 2.5 Gy for aorta, 4.4 Gy for the connective tissue, 1.6 Gy for the heart, and 2.6 Gy for trachea + bronchi. Conclusion. Increased target doses and TCP values using inhomogeneous dose distributions could be achieved for all patients, regardless of lymph node involvement, tumour stage, location, and size. These new treatment plans have the potential to increase the local tumour control by 10–15 percentage points without compromising the clinically acceptable lung toxicity level.


Radiotherapy and Oncology | 2017

Heterogeneous FDG-guided dose-escalation for locally advanced NSCLC (the NARLAL2 trial): Design and early dosimetric results of a randomized, multi-centre phase-III study

D.S. Møller; Tine Bjørn Nielsen; Carsten Brink; L. Hoffmann; Christina Maria Lutz; Mikkel D Lund; O. Hansen; Tine Schytte; Azza A. Khalil; M.M. Knap; Christa Haugaard Nyhus; Wiviann Ottosson; Patrik Sibolt; Svetlana Borissova; Mirjana Josipovic; Gitte Fredberg Persson; Ane L Appelt

BACKGROUND AND PURPOSE Local recurrence is frequent in locally advanced NSCLC and is primarily located in FDG-avid parts of tumour and lymph nodes. Aiming at improving local control without increasing toxicity, we designed a multi-centre phase-III trial delivering inhomogeneous dose-escalation driven by FDG-avid volumes, while respecting normal tissue constraints and requiring no increase in mean lung dose. Dose-escalation driven by FDG-avid volumes, delivering mean doses of 95Gy (tumour) and 74Gy (lymph nodes), was pursued and compared to standard 66Gy/33F plans. MATERIAL AND METHODS Dose plans for the first thirty patients enroled were analysed. Standard and escalated plans were created for all patients, blinded to randomization, and compared for each patient in terms of the ability to escalate while protecting normal tissue. RESULTS The median dose-escalation in FDG-avid areas was 93.9Gy (tumour) and 73.0Gy (lymph nodes). Escalation drove the GTV and CTV to mean doses for the tumour of 87.5Gy (GTV-T) and 81.3Gy (CTV-T) in median. No significant differences in mean dose to lung and heart between standard and escalated were found, but small volumes of e.g. the bronchi received doses between 66 and 74Gy due to escalation. CONCLUSIONS FDG-driven inhomogeneous dose-escalation achieves large increment in tumour and lymph node dose, while delivering similar doses to normal tissue as homogenous standard plans.


8th International Conference on 3D Radiation Dosimetry | 2015

Multicentre knowledge sharing and planning/dose audit on flattening filter free beams for SBRT lung

Christian Hansen; J. Sykes; Jeffrey Barber; K. West; R. Bromley; K. Szymura; S. Fisher; J. Sim; Michael Bailey; D. Chrystal; S. Deshpande; I. Franji; Tine Bjørn Nielsen; Carsten Brink; D.I. Thwaites

When implementing new technology into clinical practice, there will always be a need for large knowledge gain. The aim of this study was twofold, (I) audit the treatment planning and dose delivery of Flattening Filter Free (FFF) beam technology for Stereotactic Body Radiation Therapy (SBRT) of lung tumours across a range of treatment planning systems compared to the conventional Flatting Filter (FF) beams, (II) investigate how sharing knowledge between centres of different experience can improve plan quality. All vendor/treatment planning system (TPS) combinations investigated were able to produce acceptable treatment plans and the dose accuracy was clinically acceptable for all plans. By sharing knowledge between the different centres, the minor protocol violations (MPV) could be significantly reduced, from an average of 1.9 MPV per plan to 0.6 after such sharing of treatment planning knowledge. In particular, for the centres with less SBRT and/or volumetric- modulated arc therapy (VMAT) experience the MPV average per plan improved. All vendor/TPS combinations were also able to successfully deliver the FF and FFF SBRT VMAT plans. The plan quality and dose accuracy were found to be clinically acceptable.


Acta Oncologica | 2014

Four-dimensional dose evaluation of inhomogeneous dose distributions planned for non-small cell lung cancer patients with lymph node involvement.

Tine Bjørn Nielsen; Olfred Hansen; Tine Schytte; Carsten Brink

Standard three-dimensional (3D) planning studies have shown that dose escalation by use of inhomogeneous dose distribution may increase the local tumour control by more than 10 percentage points for advanced non-small cell lung cancer (NSCLC) patients [1 – 4]. Nevertheless, only a few clinical studies investigating dose escalation have been initiated [5,6]. There have been concerns regarding the dose distributions with steep gradients within the planned volume. One concern is how the respiratory motion affects the calculated 3D dose to the tumour. Another issue is whether the 3D dose to the organs at risk is representative for actual delivered dose when position uncertainties are included, or whether the steep dose gradients within the tumour might shift towards the organs at risk causing unexpected toxicity. Some studies have investigated the dosimetric effect of geometric uncertainties, e.g. respiratory motion and setup uncertainties [7 – 9]. Previously, 3D calculations of homogeneous dose distributions and dose-escalated inhomogeneous dose distributions have been studied by Nielsen et al. [1] to evaluate the potential of inhomogeneous dose escalations for NSCLC patients with involved lymph nodes. In the current study, recalculations of the same treatment plans accounting for systematic and random uncertainties (4D calculations [10,11]) were performed in order to validate dose to organs at risk and the reported tumour control probability (TCP) values.


Radiotherapy and Oncology | 2016

EP-1239: Clinical outcome of SBRT of central, apical or paracostal tumors in the lung, a retrospective study

C. Kristiansen; S.S. Jeppesen; Morten Nielsen; Tine Bjørn Nielsen; Tine Schytte; O. Hansen

S587 ________________________________________________________________________________ Material and Methods: Using the institutional databases of 3 large UK Cancer Centres (Belfast, Glasgow and Leeds), patients who had curative intent thoracic radiation for NSCLC during 2010 were identified. Baseline demographics were collated, along with details of initial irradiation, relapse and subsequent management. Summary statistics were generated detailing the incidence of re-irradiation, treatment intent of re-irradiation and dose fractionation used.


Radiotherapy and Oncology | 2016

PO-0684: Does the dose to heart affect survival in NSCLC patient treated with definitive Radiotherapy?

Tine Schytte; Tine Bjørn Nielsen; T. Stolberg-Rohr; Carsten Brink; O. Hansen

Peter MacCallum Cancer Centre, Radiation Oncology, Melbourne, Australia University Hospital Tübingen, Radiation Oncology, Tübingen, Germany Netherlands Cancer Institute Antoni van Leeuwenhoek Hospital, Radiation Oncology, Amsterdam, The Netherlands International Atomic Energy Agency, Nuclear Sciences and Application, Vienna, Austria Centre for Cancer Research and Cell Biology, Radiation Oncology, Belfast, United Kingdom


Journal of Thoracic Oncology | 2015

The NARAL" Phase III Trial: Heterogeneous FDG-GUided Dose Escalation of Advanced NSCLC: A Clinical Trial by the Danish Lung Cancer Group

D.S. Møller; Jon A. Lykkegaard Andersen; Ane L Appelt; Carsten Brink; Olfred Hansen; L. Hoffmann; Nikolaj K.G. Jensen; Mirjana Josipovic; Azza A. Khalil; M.M. Knap; Mikkel D Lund; Christina Maria Lutz; Martin Skovmos Nielsen; Svetlana Kunwald Nielsen; Tine Bjørn Nielsen; Christina H Nyhus; Wiviann Ottoson; Gitte Fredberg Persson; Patrik Sibolt; Kim Wedervang; Tine Schytte

Collaboration


Dive into the Tine Bjørn Nielsen's collaboration.

Top Co-Authors

Avatar

Carsten Brink

University of Southern Denmark

View shared research outputs
Top Co-Authors

Avatar

Tine Schytte

Odense University Hospital

View shared research outputs
Top Co-Authors

Avatar

O. Hansen

Odense University Hospital

View shared research outputs
Top Co-Authors

Avatar

Olfred Hansen

Odense University Hospital

View shared research outputs
Top Co-Authors

Avatar

Morten Nielsen

Odense University Hospital

View shared research outputs
Top Co-Authors

Avatar

Ane L Appelt

University of Southern Denmark

View shared research outputs
Top Co-Authors

Avatar

Christian Hansen

Odense University Hospital

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge