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7. Management of vertebral radiotherapy dose in paediatric patients with cancer: consensus recommendations from the SIOPE radiotherapy working group

Author

Hoeben, B.A.W., Carrie, C., Timmermann, B., Mandeville, H.C., Gandola, L., Dieckmann, K., Albiac, M. Ramos, Magelssen, H., Lassen-Ramshad, Y., Ondrova, B., Ajithkumar, T., Alapetite, C., Balgobind, B.V., Bolle, S., Cameron, A.L., Fajardo, R. Davila, Dietzsch, S., Lecomte, D. Dumont, Heuvel-Eibrink, M.M. van den, Kortmann, R.D., Laprie, A., Melchior, P., Padovani, L., Rombi, B., Scarzello, G., Schwarz, R., Seiersen, K., Seravalli, E., Thorp, N., Whitfield, G.A., Boterberg, T., Janssens, G.O., Hoeben, B.A.W., Carrie, C., Timmermann, B., Mandeville, H.C., Gandola, L., Dieckmann, K., Albiac, M. Ramos, Magelssen, H., Lassen-Ramshad, Y., Ondrova, B., Ajithkumar, T., Alapetite, C., Balgobind, B.V., Bolle, S., Cameron, A.L., Fajardo, R. Davila, Dietzsch, S., Lecomte, D. Dumont, Heuvel-Eibrink, M.M. van den, Kortmann, R.D., Laprie, A., Melchior, P., Padovani, L., Rombi, B., Scarzello, G., Schwarz, R., Seiersen, K., Seravalli, E., Thorp, N., Whitfield, G.A., Boterberg, T., and Janssens, G.O.

Abstract

Item does not contain fulltext, Inhomogeneities in radiotherapy dose distributions covering the vertebrae in children can produce long-term spinal problems, including kyphosis, lordosis, scoliosis, and hypoplasia. In the published literature, many often interrelated variables have been reported to affect the extent of potential radiotherapy damage to the spine. Articles published in the 2D and 3D radiotherapy era instructed radiation oncologists to avoid dose inhomogeneity over growing vertebrae. However, in the present era of highly conformal radiotherapy, steep dose gradients over at-risk structures can be generated and thus less harm is caused to patients. In this report, paediatric radiation oncologists from leading centres in 11 European countries have produced recommendations on how to approach dose coverage for target volumes that are adjacent to vertebrae to minimise the risk of long-term spinal problems. Based on available information, it is advised that homogeneous vertebral radiotherapy doses should be delivered in children who have not yet finished the pubertal growth spurt. If dose fall-off within vertebrae cannot be avoided, acceptable dose gradients for different age groups are detailed here. Vertebral delineation should include all primary ossification centres and growth plates, and therefore include at least the vertebral body and arch. For partial spinal radiotherapy, the number of irradiated vertebrae should be restricted as much as achievable, particularly at the thoracic level in young children (<6 years old). There is a need for multicentre research on vertebral radiotherapy dose distributions for children, but until more valid data become available, these recommendations can provide a basis for daily practice for radiation oncologists who have patients that require vertebral radiotherapy.

Published
2019

9. Electron scattering on OH-(H2O)n clusters (n=0–4).

Author

Svendsen, A., Bluhme, H., Seiersen, K., and Andersen, L. H.

Subjects
ELECTRON scattering, HYDRATION, HEAT of hydration, MOLECULES, PHYSICS, DYNAMICS
Abstract

The cross sections for electron scattering on OH-(H2O)n for n=0–4 were measured from threshold to ≈50 eV. All detachment cross sections were found to follow the classical prediction given earlier [Phys. Rev. Lett. 74, 892 (1995)] with a threshold energy for electron-impact detachment that increased upon sequential hydration, yielding values in the range from 4.5 eV±0.2 eV for OH- to 12.10 eV±0.5 eV for OH-(H2O)4. For n>=1, we found that ≈80% of the total reaction events lead to electron detachment plus total dissociation of the clusters into the constituent molecules of OH and H2O. Finally, we observed resonances in the cross sections for OH-(H2O)3 and for OH-(H2O)4. The resonances were located at ≈15 eV and were ascribed to the formation of dianions in excited states. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
2004
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10. Dissociative recombination of dications.

Author

Seiersen, K., Heber, O., Jensen, M. J., Safvan, C. P., and Andersen, L. H.

Subjects
*ION recombination, *CATIONS, *NITROGEN
Abstract

Dissociative recombination (DR) of doubly-charged positive ions has been studied at the heavy ion storage ring ASTRID. Low-energy electrons were scattered on the dication of the N[SUB2] molecule, and the absolute cross section was measured in the energy range of 10[SUP-4] - 50 eV. From the measured cross section, a thermal rate coefficient of 5.8 × 10[SUP-7]cm[SUP3]s[SUP-1] at 300 K was extracted. Furthermore, we present new results on the CO[SUP2+] DR rate, and a summary and comparison of measured DR rate coefficients for both the singly and doubly-charged ions of CO, CO[SUB2], and N[SUB2] is presented. [ABSTRACT FROM AUTHOR]

Published
2003
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14. DR of the cation and dication of CO2

Author

Seiersen, K., Al-Khalili, A., Heber, O., Jensen, M.J., Nielsen, I.B., Pedersen, H.B., Safvan, C.P., and Andersen, L.H.

Published
2003

21. EPENDYMOMA

Author

Zaghloul, M., primary, Elbeltagy, M., additional, Mousa, A., additional, Eldebawy, E., additional, Amin, A., additional, Pavelka, Z., additional, Vranova, V., additional, Valaskova, I., additional, Tomasikova, L., additional, Oltova, A., additional, Ventruba, J., additional, Mackerle, Z., additional, Kren, L., additional, Skotakova, J., additional, Zitterbart, K., additional, Sterba, J., additional, Milde, T., additional, Kleber, S., additional, Korshunov, A., additional, Witt, H., additional, Hielscher, T., additional, Koch, P., additional, Koch, H.-G., additional, Jugold, M., additional, Deubzer, H. E., additional, Oehme, I., additional, Lodrini, M., additional, Grone, H.-J., additional, Benner, A., additional, Brustle, O., additional, Gilbertson, R. J., additional, von Deimling, A., additional, Kulozik, A. E., additional, Pfister, S. M., additional, Ana, M.-V., additional, Witt, O., additional, Kool, M., additional, Mack, S. C., additional, Taylor, M. D., additional, Fouyssac, F., additional, Schmitt, E., additional, Mansuy, L., additional, Marchal, J.-C., additional, Coffinet, L., additional, Bernier, V., additional, Chastagner, P., additional, Sperl, D., additional, Zacharoulis, S., additional, Massimino, M., additional, Schiavello, E., additional, Pizer, B., additional, Piette, C., additional, Kitanovski, L., additional, von Hoff, K., additional, Quehenberger, F., additional, Rutkowski, S., additional, Benesch, M., additional, Tzaridis, T.-D., additional, Bender, S., additional, Pfaff, E., additional, Barbus, S., additional, Bageritz, J., additional, Jones, D.-T.-W., additional, Kulozik, A., additional, Lichter, P., additional, Pfister, S.-M., additional, Song, S.-H., additional, Kang, C.-W., additional, Kim, S.-H., additional, Bandopadhayay, P., additional, Ullrich, N., additional, Goumnerova, L., additional, Scott, R. M., additional, Silvera, V. M., additional, Ligon, K. L., additional, Marcus, K. J., additional, Robison, N., additional, Manley, P. E., additional, Chi, S., additional, Kieran, M. W., additional, Biassoni, V., additional, Pierani, P., additional, Cesaro, S., additional, Maura, M., additional, Mack, S., additional, Jager, N., additional, Jones, D. T. W., additional, Stutz, A., additional, Northcott, P. A., additional, Fults, D. W., additional, Gupta, N., additional, Karajannis, M., additional, Rutka, J. T., additional, Korbel, J., additional, de Rezende, A. C. P., additional, Chen, M. J., additional, da Silva, N. S., additional, Cappellano, A., additional, Cavalheiro, S., additional, Weltman, E., additional, Currle, S., additional, Thiruvenkatam, R., additional, Murugesan, M., additional, Kranenburg, T., additional, Phoenix, T., additional, Gupta, K., additional, Gilbertson, R., additional, Rogers, H., additional, Kilday, J.-P., additional, Mayne, C., additional, Ward, J., additional, Adamowicz-Brice, M., additional, Schwalbe, E., additional, Clifford, S., additional, Coyle, B., additional, Grundy, R., additional, Mitra, B., additional, Domerg, C., additional, Andreiuolo, F., additional, Osteso-Ibanez, T., additional, Mauguen, A., additional, Varlet, P., additional, Le Deley, M.-C., additional, Lowe, J., additional, Ellison, D. W., additional, Grill, J., additional, Grundy, R. G., additional, Fleischhack, G., additional, Pajtler, K., additional, Zimmermann, M., additional, Warmuth-Metz, M., additional, Kortmann, R.-D., additional, Pietsch, T., additional, Faldum, A., additional, Bode, U., additional, Gandola, L., additional, Pecori, E., additional, Scarzello, G., additional, Barra, S., additional, Mascarin, M., additional, Scoccianti, S., additional, Mussano, A., additional, Garre, M. L., additional, Jacopo, S., additional, Viscardi, E., additional, Balter, R., additional, Bertin, D., additional, Giangaspero, F., additional, Pearlman, M., additional, Khatua, S., additional, Van Meter, T., additional, Koul, D., additional, Yung, A., additional, Paulino, A., additional, Su, J., additional, Dauser, R., additional, Whitehead, W., additional, Teh, B., additional, Chintagumpala, M., additional, Perek, D., additional, Drogosiewicz, M., additional, Filipek, I., additional, Polnik, M. P., additional, Baginska, B. D., additional, Wachowiak, J., additional, Kazmierczak, B., additional, Sobol, G., additional, Musiol, K., additional, Kowalczyk, J., additional, Slusarz, H. W., additional, Peregud-Pogorzelski, J., additional, Grajkowska, W., additional, Roszkowski, M., additional, Teo, W.-Y., additional, Okcu, F., additional, Mahajan, A., additional, Adesina, A., additional, Jea, A., additional, Bollo, R., additional, Paulino, A. C., additional, Velez-Char, N., additional, Doerner, E., additional, Muehlen, A. z., additional, Vladimirova, V., additional, Kortmann, R., additional, Friedrich, C., additional, von Bueren, A. O., additional, Barszczyk, M., additional, Buczkowicz, P., additional, Morrison, A., additional, Tabori, U., additional, Hawkins, C., additional, Krajewski, K., additional, Kammler, G., additional, von Bueren, A., additional, Krauss, J., additional, Ferreira, C., additional, Dieffenbach, G., additional, Barbosa, C., additional, Cuny, P., additional, Piccinin, E., additional, Brenca, M., additional, Lorenzetto, E., additional, Sardi, I., additional, Genitori, L., additional, Pollo, B., additional, Maestro, R., additional, Modena, P., additional, MacDonald, S., additional, Ebb, D., additional, Lavally, B., additional, Yeap, B., additional, Marcus, K., additional, Tarbell, N., additional, Yock, T., additional, Schittone, S., additional, Donson, A., additional, Birks, D., additional, Amani, V., additional, Griesinger, A., additional, Handler, M., additional, Madey, M., additional, Merchant, T., additional, Foreman, N., additional, Hukin, J., additional, Ailon, T., additional, Dunham, C., additional, Carret, A.-S., additional, McNeely, P. D., additional, Zelcer, S., additional, Wilson, B., additional, Lafay-Cousin, L., additional, Johnston, D., additional, Eisenstat, D., additional, Silva, M., additional, Jabado, N., additional, Yip, S., additional, Goddard, K., additional, Fryer, C., additional, Hendson, G., additional, Dunn, S., additional, Singhal, A., additional, Lassen-Ramshad, Y., additional, Vestergaard, A., additional, Seiersen, K., additional, Schultz, H. P., additional, Hoeyer, M., additional, Petersen, J. B., additional, Moreno, L., additional, Popov, S., additional, Jury, A., additional, Al Sarraj, S., additional, Jones, C., additional, Bowers, D., additional, Gargan, L., additional, Horton, C. J., additional, Rakheja, D., additional, Margraf, L., additional, Yeung, J., additional, Hamilton, R., additional, Okada, H., additional, Jakacki, R., additional, Pollack, I., additional, Fleming, A., additional, Saint-Martin, C., additional, Freeman, C., additional, Albrecht, S., additional, and Montes, J.-L., additional

Published
2012
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32. Prediction of a CO22+layer in the atmosphere of Mars

Author

Witasse, O., primary, Dutuit, O., additional, Lilensten, J., additional, Thissen, R., additional, Zabka, J., additional, Alcaraz, C., additional, Blelly, P.-L., additional, Bougher, S. W., additional, Engel, S., additional, Andersen, L. H., additional, and Seiersen, K., additional

Published
2002
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38. Electron-impact detachment of O<SUB>3</SUB>−, NO<SUB>3</SUB>− and SO<SUB>2</SUB>− ions

Author

Seiersen, K., Bak, J., Bluhme, H., Jensen, M. J., Nielsen, S. B., and Andersen, L. H.

Abstract

Electron scattering on small negatively charged polyatomic molecules has been studied at the heavy-ion storage ring ASTRID. O3−, NO3− and SO2− ions were merged with a cold electron beam, and the relative reaction cross sections were measured for collision energies in the range from 0 to about 50 eV. The absolute magnitudes of the cross sections are predicted using a classical reaction model, and we compare all previously published detachment thresholds from storage ring experiments to the electron affinities of the corresponding atomic and molecular species. A classical over-the-barrier model predicts the atomic anion thresholds well, whereas Franck–Condon factors play a role for molecular ions. Moreover, branching ratios for molecular break-up into different final channels were determined.

Published
2003

41. Management of vertebral radiotherapy dose in paediatric patients with cancer: consensus recommendations from the SIOPE radiotherapy working group

Author

Geert O. Janssens, Beate Timmermann, Lorenza Gandola, Yasmin Lassen-Ramshad, Henriette Magelssen, Enrica Seravalli, Brian V. Balgobind, Raquel Davila Fajardo, Anne Laprie, Gillian A Whitfield, Patrick Melchior, Rudolf Schwarz, Laetitia Padovani, Barbora Ondrová, Klaus Seiersen, Monica Ramos Albiac, Stefan Dietzsch, Thankamma Ajithkumar, Rolf D. Kortmann, Karin Dieckmann, Tom Boterberg, Delphine Dumont Lecomte, Christian Carrie, Nicola Thorp, Henry Mandeville, Giovanni Scarzello, Claire Alapetite, Stéphanie Bolle, Bianca A.W. Hoeben, Alison Cameron, Marry M. van den Heuvel-Eibrink, Barbara Rombi, Hoeben B.A., Carrie C., Timmermann B., Mandeville H.C., Gandola L., Dieckmann K., Ramos Albiac M., Magelssen H., Lassen-Ramshad Y., Ondrova B., Ajithkumar T., Alapetite C., Balgobind B.V., Bolle S., Cameron A.L., Davila Fajardo R., Dietzsch S., Dumont Lecomte D., van den Heuvel-Eibrink M.M., Kortmann R.D., Laprie A., Melchior P., Padovani L., Rombi B., Scarzello G., Schwarz R., Seiersen K., Seravalli E., Thorp N., Whitfield G.A., Boterberg T., and Janssens G.O.

Subjects
Male, medicine.medical_specialty, Lordosis, medicine.medical_treatment, Medizin, Kyphosis, Review, Scoliosis, Pediatrics, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Neoplasms, Journal Article, medicine, Humans, Radiotherapy dose, Child, conformal radiotherapy, primary ossification vertebral body, Ossification, business.industry, Cancer, Radiotherapy Dosage, medicine.disease, Hypoplasia, Radiation therapy, Oncology, Child, Preschool, 030220 oncology & carcinogenesis, Radiation Oncology, Female, Radiology, Radiotherapy, Conformal, medicine.symptom, business, Rare cancers Radboud Institute for Health Sciences [Radboudumc 9]
Abstract

Item does not contain fulltext Inhomogeneities in radiotherapy dose distributions covering the vertebrae in children can produce long-term spinal problems, including kyphosis, lordosis, scoliosis, and hypoplasia. In the published literature, many often interrelated variables have been reported to affect the extent of potential radiotherapy damage to the spine. Articles published in the 2D and 3D radiotherapy era instructed radiation oncologists to avoid dose inhomogeneity over growing vertebrae. However, in the present era of highly conformal radiotherapy, steep dose gradients over at-risk structures can be generated and thus less harm is caused to patients. In this report, paediatric radiation oncologists from leading centres in 11 European countries have produced recommendations on how to approach dose coverage for target volumes that are adjacent to vertebrae to minimise the risk of long-term spinal problems. Based on available information, it is advised that homogeneous vertebral radiotherapy doses should be delivered in children who have not yet finished the pubertal growth spurt. If dose fall-off within vertebrae cannot be avoided, acceptable dose gradients for different age groups are detailed here. Vertebral delineation should include all primary ossification centres and growth plates, and therefore include at least the vertebral body and arch. For partial spinal radiotherapy, the number of irradiated vertebrae should be restricted as much as achievable, particularly at the thoracic level in young children (

Published
2019
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44. ESTRO ACROP and SIOPE recommendations for myeloablative Total Body Irradiation in children.

Author

Hoeben BAW, Pazos M, Seravalli E, Bosman ME, Losert C, Albert MH, Boterberg T, Ospovat I, Mico Milla S, Demiroz Abakay C, Engellau J, Jóhannesson V, Kos G, Supiot S, Llagostera C, Bierings M, Scarzello G, Seiersen K, Smith E, Ocanto A, Ferrer C, Bentzen SM, Kobyzeva DA, Loginova AA, and Janssens GO

Subjects
Bone Marrow, Child, Child, Preschool, Humans, Retrospective Studies, Transplantation Conditioning methods, Hematopoietic Stem Cell Transplantation adverse effects, Hematopoietic Stem Cell Transplantation methods, Whole-Body Irradiation adverse effects, Whole-Body Irradiation methods
Abstract

Background and Purpose: Myeloablative Total Body Irradiation (TBI) is an important modality in conditioning for allogeneic hematopoietic stem cell transplantation (HSCT), especially in children with high-risk acute lymphoblastic leukemia (ALL). TBI practices are heterogeneous and institution-specific. Since TBI is associated with multiple late adverse effects, recommendations may help to standardize practices and improve the outcome versus toxicity ratio for children., Material and Methods: The European Society for Paediatric Oncology (SIOPE) Radiotherapy TBI Working Group together with ESTRO experts conducted a literature search and evaluation regarding myeloablative TBI techniques and toxicities in children. Findings were discussed in bimonthly virtual meetings and consensus recommendations were established., Results: Myeloablative TBI in HSCT conditioning is mostly performed for high-risk ALL patients or patients with recurring hematologic malignancies. TBI is discouraged in children <3-4 years old because of increased toxicity risk. Publications regarding TBI are mostly retrospective studies with level III-IV evidence. Preferential TBI dose in children is 12-14.4 Gy in 1.6-2 Gy fractions b.i.d. Dose reduction should be considered for the lungs to <8 Gy, for the kidneys to ≤10 Gy, and for the lenses to <12 Gy, for dose rates ≥6 cGy/min. Highly conformal techniques i.e. TomoTherapy and VMAT TBI or Total Marrow (and/or Lymphoid) Irradiation as implemented in several centers, improve dose homogeneity and organ sparing, and should be evaluated in studies., Conclusions: These ESTRO ACROP SIOPE recommendations provide expert consensus for conventional and highly conformal myeloablative TBI in children, as well as a supporting literature overview of TBI techniques and toxicities., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Published
2022
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45. Inter-observer variation in target delineation and dose trade-off for radiotherapy of paediatric ependymoma.

Author

Toussaint L, Brandal P, Embring A, Engellau J, Evensen ME, Griskeviskius R, Hansen J, Hietala H, Wickart Johansson G, Jørgensen M, Kramer PH, Kristensen I, Lehtio K, Magelssen H, Maraldo MV, Marienhagen K, Martinsson U, Nilsson K, Peters S, Plaude S, Seiersen K, Sendiuliene D, Smulders B, Edvardsen T, Søbstad JM, Taheri Z, Vaalavirta L, Vestergaard A, Timmermann B, and Lassen-Ramshad Y

Subjects
Child, Humans, Observer Variation, Radiotherapy Planning, Computer-Assisted, Ependymoma radiotherapy, Radiation Oncology
Published
2022
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46. Advances in radiotherapy technology for pediatric cancer patients and roles of medical physicists: COG and SIOP Europe perspectives.

Author

Hua CH, Mascia AE, Seravalli E, Lomax AJ, Seiersen K, and Ulin K

Subjects
Child, Europe, Humans, Neoplasms radiotherapy, Practice Guidelines as Topic standards, Radiation Oncology organization & administration, Radiation Oncology standards, Radiotherapy methods
Abstract

Over the last two decades, rapid technological advances have dramatically changed radiation delivery to children with cancer, enabling improved normal-tissue sparing. This article describes recent advances in photon and proton therapy technologies, image-guided patient positioning, motion management, and adaptive therapy that are relevant to pediatric cancer patients. For medical physicists who are at the forefront of realizing the promise of technology, challenges remain with respect to ensuring patient safety as new technologies are implemented with increasing treatment complexity. The contributions of medical physicists to meeting these challenges in daily practice, in the conduct of clinical trials, and in pediatric oncology cooperative groups are highlighted. Representing the perspective of the physics committees of the Children's Oncology Group (COG) and the European Society for Paediatric Oncology (SIOP Europe), this paper provides recommendations regarding the safe delivery of pediatric radiotherapy. Emerging innovations are highlighted to encourage pediatric applications with a view to maximizing the therapeutic ratio., (© 2021 Wiley Periodicals LLC.)

Published
2021
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47. Training and education of pediatric radiation oncologists: A survey from the 2019 Pediatric Radiation Oncology Society meeting.

Author

Paulino AC, Dieckmann K, Esiashvili N, Mahajan A, Janssens GO, Halperin EC, Carrie C, Parkes J, Wolden SL, Seiersen K, Awrey S, Dieter-Kortmann R, and Marcus KJ

Subjects
Child, Female, Humans, Male, Surveys and Questionnaires, Attitude of Health Personnel, Education, Medical, Continuing standards, Neoplasms radiotherapy, Pediatrics education, Radiation Oncologists education, Radiation Oncology education
Abstract

To examine the educational background, clinical practice, and preferences regarding continuing medical education (CME) among radiation oncologists who attended the 2019 meeting of the Pediatric Radiation Oncology Society (PROS), a survey consisting of 20 questions was distributed asking for demographic and educational background, clinical practice, and preferences regarding pediatric radiation oncology CME. Of 188 participants, 130 (69.2%) returned the questionnaire. More than 80% reported access to CT simulation, three-dimensional radiotherapy, and general anesthesia while <30% had access to intraoperative radiotherapy, proton, and heavy particle therapy. After residency, 12.1% did further training in pediatric radiation oncology. When asked about further training in pediatrics after residency, 88.8% answered that there should be a formal training program beyond residency in order to treat children. More than 75% acquired knowledge in pediatric radiation oncology through journals, books, live meetings, and tumor boards. The results of this survey may help Pediatric Radiation Oncology Society (PROS) in creating guidelines and recommendations for improvement in pediatric radiation oncology training and practice support as well as the development of CME activities most likely to benefit practitioners., (© 2020 Wiley Periodicals LLC.)

Published
2020
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48. Management of vertebral radiotherapy dose in paediatric patients with cancer: consensus recommendations from the SIOPE radiotherapy working group.

Author

Hoeben BA, Carrie C, Timmermann B, Mandeville HC, Gandola L, Dieckmann K, Ramos Albiac M, Magelssen H, Lassen-Ramshad Y, Ondrová B, Ajithkumar T, Alapetite C, Balgobind BV, Bolle S, Cameron AL, Davila Fajardo R, Dietzsch S, Dumont Lecomte D, van den Heuvel-Eibrink MM, Kortmann RD, Laprie A, Melchior P, Padovani L, Rombi B, Scarzello G, Schwarz R, Seiersen K, Seravalli E, Thorp N, Whitfield GA, Boterberg T, and Janssens GO

Subjects
Child, Child, Preschool, Female, Humans, Male, Neoplasms pathology, Radiation Oncology standards, Neoplasms radiotherapy, Pediatrics standards, Radiotherapy Dosage standards, Radiotherapy, Conformal standards
Abstract

Inhomogeneities in radiotherapy dose distributions covering the vertebrae in children can produce long-term spinal problems, including kyphosis, lordosis, scoliosis, and hypoplasia. In the published literature, many often interrelated variables have been reported to affect the extent of potential radiotherapy damage to the spine. Articles published in the 2D and 3D radiotherapy era instructed radiation oncologists to avoid dose inhomogeneity over growing vertebrae. However, in the present era of highly conformal radiotherapy, steep dose gradients over at-risk structures can be generated and thus less harm is caused to patients. In this report, paediatric radiation oncologists from leading centres in 11 European countries have produced recommendations on how to approach dose coverage for target volumes that are adjacent to vertebrae to minimise the risk of long-term spinal problems. Based on available information, it is advised that homogeneous vertebral radiotherapy doses should be delivered in children who have not yet finished the pubertal growth spurt. If dose fall-off within vertebrae cannot be avoided, acceptable dose gradients for different age groups are detailed here. Vertebral delineation should include all primary ossification centres and growth plates, and therefore include at least the vertebral body and arch. For partial spinal radiotherapy, the number of irradiated vertebrae should be restricted as much as achievable, particularly at the thoracic level in young children (<6 years old). There is a need for multicentre research on vertebral radiotherapy dose distributions for children, but until more valid data become available, these recommendations can provide a basis for daily practice for radiation oncologists who have patients that require vertebral radiotherapy., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Published
2019
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49. Functional image-guided dose escalation in gliomas using of state-of-the-art photon vs. proton therapy.

Author

Holm AIS, Petersen JBB, Muren LP, Seiersen K, Borghammer P, and Lukacova S

Subjects
Adult, Aged, Brain Neoplasms diagnostic imaging, Brain Neoplasms pathology, Female, Glioma diagnostic imaging, Glioma pathology, Humans, Image Processing, Computer-Assisted methods, Male, Middle Aged, Neoplasm Recurrence, Local diagnostic imaging, Neoplasm Recurrence, Local pathology, Organs at Risk radiation effects, Positron-Emission Tomography, Radiotherapy Dosage, Radiotherapy, Intensity-Modulated methods, Brain Neoplasms radiotherapy, Glioma radiotherapy, Neoplasm Recurrence, Local radiotherapy, Photons therapeutic use, Proton Therapy, Radiotherapy Planning, Computer-Assisted methods, Radiotherapy, Image-Guided methods
Abstract

Background: Recurrences of glioma are usually local, suggesting the need for higher tumor dose. We investigated the boundaries for dose escalation of an 18 F-fluoro-ethyl-tyrosine positron emission tomography defined target by intensity-modulated photon therapy (IMRT), volumetric modulated arc therapy (VMAT) and intensity-modulated proton therapy (IMPT)., Materials and Methods: Standard dose (60 Gy) and dose-escalated plans were calculated for seven patients using IMRT, VMAT and IMPT. The achieved boost dose, the dose to the organs at risk (OAR), the dose homogeneity (defined as overdose volume, ODV) and the ratio of the 30 Gy isodose curve and the boost volume (R30) were compared. The risk of radionecrosis was estimated using the ratio of the dose volume histograms of the brain (range 30-60 Gy)., Results: The mean boost dose was 77.1 Gy for IMRT, 79.2 Gy for VMAT and 85.1 GyE for IMPT. Compared with the standard plan, the ODV was unchanged and the R30 increased (17%) for IMRT. For VMAT, the ODV decreased (7%) and the R30 was unchanged whereas IMPT substantially decreased ODV (61%), R30 (22%), OAR doses as well as the risk of radionecrosis., Conclusions: Dose escalation can be achieved with IMRT, VMAT and IMPT while respecting normal tissue constraints, yet with IMPT being most favorable.

Published
2017
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50. Paediatric radiation oncology in the care of childhood cancer: A position paper by the International Paediatric Radiation Oncology Society (PROS).

Author

Kortmann RD, Freeman C, Marcus K, Claude L, Dieckmann K, Halperin E, Esiashvili N, Paulino A, Mahajan A, Seiersen K, Ahern V, Ricardi U, and Carrie C

Subjects
Adolescent, Child, Humans, Intersectoral Collaboration, Neoplasms radiotherapy, Radiation Oncology methods
Abstract

Paediatric malignancies are a challenge for the radiation oncologist due to their rarity, the great variety of histological types, and the complexity of treatment concepts that evolve over time. The Paediatric Radiation Oncology Society (PROS) is the only internationally operating society for paediatric radiation oncology. The objectives of PROS are to set a world-wide standard of excellence with respect to radiation oncology aspects in curing children and adolescents with cancer, to provide a forum for communication between radiation oncologists, and to exchange information with all professionals involved in the management of paediatric and adolescent cancer. Challenges include the need to promote education and support practice in low and middle income countries (LMIC) as well as the cost and availability of modern treatment technologies for all but most especially these countries. Collaborations with other societies that include for example the education programmes provided jointly with ESTRO, and the upgraded technical platform of the PROS web site offer new possibilities to enhance the efficacy of PROS in education and support of paediatric radiation oncology practice world-wide. PROS has made an important contribution to the management of childhood malignancies over the past decade and new and developing collaborations between PROS and other societies or organizations will ultimately lead to a reduction in world-wide health care inequalities., (Copyright © 2016. Published by Elsevier Ireland Ltd.)

Published
2016
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