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Zackrisson, Björn
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Publications (10 of 54) Show all publications
Adjeiwaah, M., Bylund, M., Lundman, J. A., Söderström, K., Zackrisson, B., Jonsson, J. H., . . . Nyholm, T. (2019). Dosimetric Impact of MRI Distortions: A Study on Head and Neck Cancers. International Journal of Radiation Oncology, Biology, Physics, 103(4), 994-1003
Open this publication in new window or tab >>Dosimetric Impact of MRI Distortions: A Study on Head and Neck Cancers
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2019 (English)In: International Journal of Radiation Oncology, Biology, Physics, ISSN 0360-3016, E-ISSN 1879-355X, Vol. 103, no 4, p. 994-1003Article in journal (Refereed) Published
Abstract [en]

Purpose: To evaluate the effect of magnetic resonance (MR) imaging (MRI) geometric distortions on head and neck radiation therapy treatment planning (RTP) for an MRI-only RTP. We also assessed the potential benefits of patient-specific shimming to reduce the magnitude of MR distortions for a 3-T scanner.

Methods and Materials: Using an in-house Matlab algorithm, shimming within entire imaging volumes and user-defined regions of interest were simulated. We deformed 21 patient computed tomography (CT) images with MR distortion fields (gradient nonlinearity and patient-induced susceptibility effects) to create distorted CT (dCT) images using bandwidths of 122 and 488 Hz/mm at 3 T. Field parameters from volumetric modulated arc therapy plans initially optimized on dCT data sets were transferred to CT data to compute a new plan. Both plans were compared to determine the impact of distortions on dose distributions.

Results: Shimming across entire patient volumes decreased the percentage of voxels with distortions of more than 2 mm from 15.4% to 2.0%. Using the user-defined region of interest (ROI) shimming strategy, (here the Planning target volume (PTV) was the chosen ROI volume) led to increased geometric for volumes outside the PTV, as such voxels within the spinal cord with geometric shifts above 2 mm increased from 11.5% to 32.3%. The worst phantom-measured residual system distortions after 3-dimensional gradient nonlinearity correction within a radial distance of 200 mm from the isocenter was 2.17 mm. For all patients, voxels with distortion shifts of more than 2 mm resulting from patient-induced susceptibility effects were 15.4% and 0.0% using bandwidths of 122 Hz/mm and 488 Hz/mm at 3 T. Dose differences between dCT and CT treatment plans in D-50 at the planning target volume were 0.4% +/- 0.6% and 0.3% +/- 0.5% at 122 and 488 Hz/mm, respectively.

Conclusions: The overall effect of MRI geometric distortions on data used for RTP was minimal. Shimming over entire imaging volumes decreased distortions, but user-defined subvolume shimming introduced significant errors in nearby organs and should probably be avoided.

Place, publisher, year, edition, pages
Elsevier, 2019
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:umu:diva-157192 (URN)10.1016/j.ijrobp.2018.11.037 (DOI)000459153600031 ()30496879 (PubMedID)
Available from: 2019-04-15 Created: 2019-04-15 Last updated: 2019-10-31Bibliographically approved
Zborayova, K., Antti, H., Blomqvist, L., Flygare, L., Gebre-Medhin, M., Jonsson, J., . . . Zackrisson, B. (2019). Early changes in multiparametric imaging parameters during radiotherapy of squamous carcinoma. Paper presented at 7th International Congress on Innovative Approaches in Head and Neck Oncology (ICHNO), Barcelona, SPAIN, MAR 14-16, 2019.. Radiotherapy and Oncology, 132, 63-63
Open this publication in new window or tab >>Early changes in multiparametric imaging parameters during radiotherapy of squamous carcinoma
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2019 (English)In: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 132, p. 63-63Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
Elsevier, 2019
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:umu:diva-158753 (URN)10.1016/S0167-8140(19)30289-0 (DOI)000463820400107 ()
Conference
7th International Congress on Innovative Approaches in Head and Neck Oncology (ICHNO), Barcelona, SPAIN, MAR 14-16, 2019.
Note

Supplement 1.

Available from: 2019-05-15 Created: 2019-05-15 Last updated: 2019-05-15Bibliographically approved
Olsson, C., Nyholm, T., Wieslander, E., Zackrisson, B. & Valdman, A. (2019). Initial Experience with Introducing National Swedish Guidelines for CT- and MRI-based Delineation of Organs at Risk in Radiotherapy: The STRONG Project. Paper presented at 61st Annual Meeting of the American Society for Radiation Oncology (ASTRO), Chicago, Sep 15-18, 2019. International Journal of Radiation Oncology, Biology, Physics, 105(1), E620-E620
Open this publication in new window or tab >>Initial Experience with Introducing National Swedish Guidelines for CT- and MRI-based Delineation of Organs at Risk in Radiotherapy: The STRONG Project
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2019 (English)In: International Journal of Radiation Oncology, Biology, Physics, ISSN 0360-3016, E-ISSN 1879-355X, Vol. 105, no 1, p. E620-E620Article in journal, Meeting abstract (Refereed) Published
Place, publisher, year, edition, pages
Elsevier, 2019
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:umu:diva-164420 (URN)10.1016/j.ijrobp.2019.06.1152 (DOI)000485671501714 ()
Conference
61st Annual Meeting of the American Society for Radiation Oncology (ASTRO), Chicago, Sep 15-18, 2019
Note

Supplement S, Meeting Abstract 3435.

Available from: 2019-10-22 Created: 2019-10-22 Last updated: 2019-10-22Bibliographically approved
Widmark, A., Gunnlaugsson, A., Beckman, L., Thellenberg-Karlsson, C., Hoyer, M., Lagerlund, M., . . . Nilsson, P. (2019). Ultra-hypofractionated versus conventionally fractionated radiotherapy for prostate cancer: 5-year outcomes of the HYPO-RT-PC randomised, non-inferiority, phase 3 trial. The Lancet, 394(10196), 385-395
Open this publication in new window or tab >>Ultra-hypofractionated versus conventionally fractionated radiotherapy for prostate cancer: 5-year outcomes of the HYPO-RT-PC randomised, non-inferiority, phase 3 trial
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2019 (English)In: The Lancet, ISSN 0140-6736, E-ISSN 1474-547X, Vol. 394, no 10196, p. 385-395Article in journal (Refereed) Published
Abstract [en]

Background: Hypofractionated radiotherapy for prostate cancer has gained increased attention due to its proposed high radiation-fraction sensitivity. Recent reports from studies comparing moderately hypofractionated and conventionally fractionated radiotherapy support the clinical use of moderate hypofractionation. To date, there are no published randomised studies on ultra-hypofractionated radiotherapy. Here, we report the outcomes of the Scandinavian HYPO-RT-PC phase 3 trial with the aim to show non-inferiority of ultra-hypofractionation compared with conventional fractionation.

Methods: In this open-label, randomised, phase 3 non-inferiority trial done in 12 centres in Sweden and Denmark, we recruited men up to 75 years of age with intermediate-to-high-risk prostate cancer and a WHO performance status between 0 and 2. Patients were randomly assigned to ultra-hypofractionation (42·7 Gy in seven fractions, 3 days per week for 2·5 weeks) or conventional fractionated radiotherapy (78·0 Gy in 39 fractions, 5 days per week for 8 weeks). No androgen deprivation therapy was allowed. The primary endpoint was time to biochemical or clinical failure, analysed in the per-protocol population. The prespecified non-inferiority margin was 4% at 5 years, corresponding to a critical hazard ratio (HR) limit of 1·338. Physician-recorded toxicity was measured according to the Radiation Therapy Oncology Group (RTOG) morbidity scale and patient-reported outcome measurements with the Prostate Cancer Symptom Scale (PCSS) questionnaire. This trial is registered with the ISRCTN registry, number ISRCTN45905321.

Findings: Between July 1, 2005, and Nov 4, 2015, 1200 patients were randomly assigned to conventional fractionation (n=602) or ultra-hypofractionation (n=598), of whom 1180 (591 conventional fractionation and 589 ultra-hypofractionation) constituted the per-protocol population. 1054 (89%) participants were intermediate risk and 126 (11%) were high risk. Median follow-up time was 5·0 years (IQR 3·1–7·0). The estimated failure-free survival at 5 years was 84% (95% CI 80–87) in both treatment groups, with an adjusted HR of 1·002 (95% CI 0·758–1·325; log-rank p=0·99). There was weak evidence of an increased frequency of acute physician-reported RTOG grade 2 or worse urinary toxicity in the ultra-hypofractionation group at end of radiotherapy (158 [28%] of 569 patients vs 132 [23%] of 578 patients; p=0·057). There were no significant differences in grade 2 or worse urinary or bowel late toxicity between the two treatment groups at any point after radiotherapy, except for an increase in urinary toxicity in the ultra-hypofractionation group compared to the conventional fractionation group at 1-year follow-up (32 [6%] of 528 patients vs 13 [2%] of 529 patients; (p=0·0037). We observed no differences between groups in frequencies at 5 years of RTOG grade 2 or worse urinary toxicity (11 [5%] of 243 patients for the ultra-hypofractionation group vs 12 [5%] of 249 for the conventional fractionation group; p=1·00) and bowel toxicity (three [1%] of 244 patients vs nine [4%] of 249 patients; p=0·14). Patient-reported outcomes revealed significantly higher levels of acute urinary and bowel symptoms in the ultra-hypofractionation group compared with the conventional fractionation group but no significant increases in late symptoms were found, except for increased urinary symptoms at 1-year follow-up, consistent with the physician-evaluated toxicity.

Interpretation: Ultra-hypofractionated radiotherapy is non-inferior to conventionally fractionated radiotherapy for intermediate-to-high risk prostate cancer regarding failure-free survival. Early side-effects are more pronounced with ultra-hypofractionation compared with conventional fractionation whereas late toxicity is similar in both treatment groups. The results support the use of ultra-hypofractionation for radiotherapy of prostate cancer.

Funding: The Nordic Cancer Union, the Swedish Cancer Society, and the Swedish Research Council.

Place, publisher, year, edition, pages
Elsevier, 2019
National Category
Nursing
Identifiers
urn:nbn:se:umu:diva-162730 (URN)10.1016/S0140-6736(19)31131-6 (DOI)000478698300023 ()31227373 (PubMedID)2-s2.0-85069673767 (Scopus ID)
Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2019-08-30Bibliographically approved
Nyholm, T., Svensson, S., Andersson, S., Jonsson, J., Sohlin, M., Gustafsson, C., . . . Gunnlaugsson, A. (2018). MR and CT data with multiobserver delineations of organs in the pelvic area: Part of the Gold Atlas project. Medical physics (Lancaster), 45(3), 1295-1300
Open this publication in new window or tab >>MR and CT data with multiobserver delineations of organs in the pelvic area: Part of the Gold Atlas project
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2018 (English)In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 45, no 3, p. 1295-1300Article in journal (Refereed) Published
Abstract [en]

Purpose: We describe a public dataset with MR and CT images of patients performed in the same position with both multiobserver and expert consensus delineations of relevant organs in the male pelvic region. The purpose was to provide means for training and validation of segmentation algorithms and methods to convert MR to CT like data, i.e., so called synthetic CT (sCT).

Acquisition and validation methods: T1- and T2-weighted MR images as well as CT data were collected for 19 patients at three different departments. Five experts delineated nine organs for each patient based on the T2-weighted MR images. An automatic method was used to fuse the delineations. Starting from each fused delineation, a consensus delineation was agreed upon by the five experts for each organ and patient. Segmentation overlap between user delineations with respect to the consensus delineations was measured to describe the spread of the collected data. Finally, an open-source software was used to create deformation vector fields describing the relation between MR and CT images to further increase the usability of the dataset.

Data format and usage notes: The dataset has been made publically available to be used for academic purposes, and can be accessed from . Potential applicationsThe dataset provides a useful source for training and validation of segmentation algorithms as well as methods to convert MR to CT-like data (sCT). To give some examples: The T2-weighted MR images with their consensus delineations can directly be used as a template in an existing atlas-based segmentation engine; the expert delineations are useful to validate the performance of a segmentation algorithm as they provide a way to measure variability among users which can be compared with the result of an automatic segmentation; and the pairwise deformably registered MR and CT images can be a source for an atlas-based sCT algorithm or for validation of sCT algorithm.

Place, publisher, year, edition, pages
John Wiley & Sons, 2018
Keywords
CT, MRI, open dataset, organs at risk, radiotherapy
National Category
Medical Image Processing
Identifiers
urn:nbn:se:umu:diva-146581 (URN)10.1002/mp.12748 (DOI)000427129700032 ()29322528 (PubMedID)
Available from: 2018-06-26 Created: 2018-06-26 Last updated: 2018-06-26Bibliographically approved
Zakeri, K., Rotolo, F., Lacas, B., Vitzthum, L. K., Le, Q.-T., Gregoire, V., . . . Mell, L. K. (2018). Predictor of effectiveness of treatment intensification on overall survival in head and neck cancer (HNC). Paper presented at 43rd ESMO Congress (ESMO), Munich, Germany, 19-23 October, 2018. Annals of Oncology, 29
Open this publication in new window or tab >>Predictor of effectiveness of treatment intensification on overall survival in head and neck cancer (HNC)
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2018 (English)In: Annals of Oncology, ISSN 0923-7534, E-ISSN 1569-8041, Vol. 29Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
Oxford University Press, 2018
National Category
Cancer and Oncology
Identifiers
urn:nbn:se:umu:diva-157239 (URN)10.1093/annonc/mdy287.008 (DOI)000459277302230 ()
Conference
43rd ESMO Congress (ESMO), Munich, Germany, 19-23 October, 2018
Note

Supplement 8

Meeting abstract 1052PD

Available from: 2019-03-18 Created: 2019-03-18 Last updated: 2019-03-18Bibliographically approved
Lassen, P., Lacas, B., Pignon, J. P., Trotti, A., Zackrisson, B., Zhang, Q., . . . Blanchard, P. (2018). Prognostic Impact of HPV-Associated p16 Expression and Smoking Status on Outcomes Following Radiation Therapy for Oropharyngeal Cancer: the MARCH-HPV Project. Paper presented at Multidisciplinary Head and Neck Cancers Symposium, FEB 15-17, 2018, Scottsdale, AZ. International Journal of Radiation Oncology, Biology, Physics, 100(5), 1332-1332
Open this publication in new window or tab >>Prognostic Impact of HPV-Associated p16 Expression and Smoking Status on Outcomes Following Radiation Therapy for Oropharyngeal Cancer: the MARCH-HPV Project
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2018 (English)In: International Journal of Radiation Oncology, Biology, Physics, ISSN 0360-3016, E-ISSN 1879-355X, Vol. 100, no 5, p. 1332-1332Article in journal, Meeting abstract (Other academic) Published
Place, publisher, year, edition, pages
Elsevier, 2018
National Category
Cancer and Oncology
Identifiers
urn:nbn:se:umu:diva-146552 (URN)000428145600097 ()
Conference
Multidisciplinary Head and Neck Cancers Symposium, FEB 15-17, 2018, Scottsdale, AZ
Note

Meeting Abstract: 131

Available from: 2018-08-07 Created: 2018-08-07 Last updated: 2018-08-07Bibliographically approved
Lassen, P., Lacas, B., Pignon, J.-P., Trotti, A., Zackrisson, B., Zhang, Q., . . . Blanchard, P. (2018). Prognostic impact of HPV-associated p16-expression and smoking status on outcomes following radiotherapy for oropharyngeal cancer: the MARCH-HPV project. Paper presented at 15th International Wolfsberg Meeting on Molecular Radiation Biology/Oncology, JUN 17-19, 2017, SWITZERLAND. Radiotherapy and Oncology, 126(1), 107-115
Open this publication in new window or tab >>Prognostic impact of HPV-associated p16-expression and smoking status on outcomes following radiotherapy for oropharyngeal cancer: the MARCH-HPV project
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2018 (English)In: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 126, no 1, p. 107-115Article in journal (Refereed) Published
Abstract [en]

Background and purpose: Evaluate the prognostic and predictive impact of HPV-associated p16 -expression and assess the combined prognostic impact of p16 and smoking on altered fractionated radiotherapy (AFRT) for oropharyngeal cancer (OPC) within the frames of the update of the Meta-Analysis of Radiotherapy in Carcinomas of Head and neck (MARCH). Materials and methods: Patients with OPC, known tumor p16-status and smoking history were identified from the MARCH update, resulting in a dataset of 815 patients from four randomized trials (RTOG9003, DAHANCA6&7, RTOG0129, ARTSCAN). Analysis was performed using a Cox model stratified by trial and adjusted on gender, age, T-stage, N-stage, type of radiotherapy fractionation, p16, smoking. Primary end-point was progression-free survival (PFS). Results: In total, 465 patients (57%) had p16-positive tumors and 350 (43%) p16-negative. Compared to p16-negative, p16-positive patients had significantly better PFS (HR = 0.42 [95% CI: 0.34-0.51], 28.9% absolute increase at 10 years) and OS (HR = 0.40 [0.32-0.49], 32.1% absolute increase at 10 years). No interaction between p16-status and fractionation schedule was detected. Smoking negatively impacted outcome; in the p16-positive subgroup, never smokers had significantly better PFS than former/current smokers (HR = 0.49 [0.33-0.75], 24.2% survival benefit at 10 years). Conclusions: No predictive impact of p16-status on response to AFRT could be detected but the strong prognostic impact of p16-status was confirmed and especially p16-positive never smoking patients have superior outcome after RT. 

Place, publisher, year, edition, pages
ELSEVIER IRELAND LTD, 2018
Keywords
FIPV, Smoking, Oropharynx carcinoma, Prognostic, Radiotherapy, Altered fractionation
National Category
Cancer and Oncology
Identifiers
urn:nbn:se:umu:diva-145808 (URN)10.1016/j.radonc.2017.10.018 (DOI)000425578100014 ()29100700 (PubMedID)
Conference
15th International Wolfsberg Meeting on Molecular Radiation Biology/Oncology, JUN 17-19, 2017, SWITZERLAND
Available from: 2018-03-22 Created: 2018-03-22 Last updated: 2018-06-09Bibliographically approved
Brynolfsson, P., Axelsson, J., Holmberg, A., Jonsson, J., Goldhaber, D., Jian, Y., . . . Nyholm, T. (2018). Technical note: adapting a GE SIGNA PET/MR scanner for radiotherapy. Medical physics (Lancaster), 45(8), 3546-3550
Open this publication in new window or tab >>Technical note: adapting a GE SIGNA PET/MR scanner for radiotherapy
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2018 (English)In: Medical physics (Lancaster), ISSN 0094-2405, Vol. 45, no 8, p. 3546-3550Article in journal (Refereed) Published
Abstract [en]

Purpose: Simultaneous collection of PET and MR data for radiotherapy purposes are useful for, for example, target definition and dose escalations. However, a prerequisite for using PET/MR in the radiotherapy workflow is the ability to image the patient in treatment position. The aim of this work was to adapt a GE SIGNA PET/MR scanner to image patients for radiotherapy treatment planning and evaluate the impact on signal-to-noise (SNR) of the MR images, and the accuracy of the PET attenuation correction. Method: A flat tabletop and a coil holder were developed to image patients in the treatment position, avoid patient contour deformation, and facilitate attenuation correction of flex coils. Attenuation corrections for the developed hardware and an anterior array flex coil were also measured and implemented to the PET/MR system to minimize PET quantitation errors. The reduction of SNR in the MR images due to the added distance between the coils and the patient was evaluated using a large homogenous saline-doped water phantom, and the activity quantitation errors in PET imaging were evaluated with and without the developed attenuation corrections. Result: We showed that the activity quantitation errors in PET imaging were within ±5% when correcting for attenuation of the flat tabletop, coil holder, and flex coil. The SNR of the MRI images were reduced to 74% using the tabletop, and 66% using the tabletop and coil holders. Conclusion: We present a tabletop and coil holder for an anterior array coil to be used with a GE SIGNA PET/MR scanner, for scanning patients in the radiotherapy work flow. Implementing attenuation correction of the added hardware from the radiotherapy setup leads to acceptable PET image quantitation. The drop in SNR in MR images may require adjustment of the imaging protocols.

Place, publisher, year, edition, pages
Wiley-Blackwell Publishing Inc., 2018
Keywords
MRI, PET, PET, MR, quality assurance, radiotherapy
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:umu:diva-151405 (URN)10.1002/mp.13032 (DOI)000441292000009 ()29862522 (PubMedID)
Funder
VINNOVA
Available from: 2018-09-03 Created: 2018-09-03 Last updated: 2018-09-04Bibliographically approved
Mäkitie, A., Ruuskanen, M., Bentzen, J., Brun, E., Gebre-Medhin, M., Friesland, S., . . . Saarilahti, K. (2018). The management and survival outcomes of nasopharyngeal cancer in the Nordic countries [Letter to the editor]. Acta Oncologica, 57(4), 557-560
Open this publication in new window or tab >>The management and survival outcomes of nasopharyngeal cancer in the Nordic countries
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2018 (English)In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 57, no 4, p. 557-560Article in journal, Letter (Refereed) Published
Place, publisher, year, edition, pages
Taylor & Francis, 2018
National Category
Cancer and Oncology
Identifiers
urn:nbn:se:umu:diva-146596 (URN)10.1080/0284186X.2017.1408961 (DOI)000427934300017 ()29202641 (PubMedID)
Available from: 2018-05-08 Created: 2018-05-08 Last updated: 2018-06-09Bibliographically approved
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