Open Access Open Access  Restricted Access Subscription Access
Open Access Open Access Open Access  Restricted Access Restricted Access Subscription Access

Assessments and Dosimatric Evaluation of Matching Fields Technique in the Treatment Cranio-Spinal Cancers


Affiliations
1 Al-Mustansiriya University, College of Medicine, Iraq
2 Dept. of Physiology, Medical Physics Unit, Al-Mustansiriya University, Medical College, Iraq
3 Director Baghdad Center of Radiotherapy and Nuclear Medicine, Iraq
     

   Subscribe/Renew Journal


Radiotherapy is one of the main methods of cancer treatment (often with chemotherapy and surgery) and is generally assumed to be 50 to 60% of cancer patients will benefit from radiotherapy, where radiation therapy is done using the Linear accelerator device. medulloblastoma, a primitive tumor growing in the cerebellum, is one of the most sensitive tumors in the childhood brain to radiotherapy. The most common malignant tumor in children is cancerous tumor with an overall infection among children aged 0-19 from 16 to 20 percent of all brain tumors in hospitals. Radiotherapy is an essential means of treating these tumors and, after surgery, radiation therapy has a significant impact, This study was conducted to understand the impact of the possibilities that could occur during the process of radiotherapy through systemic and irregular errors when set-up the patient for treatment on the occurrence of cold spots and hot spots and the risk of dose at both the craniospinal at treatment. Objectives: Aim of The Work To evaluate the dosimetry homogeneity abutting junction between photon-photon fields in treatment cranio-spinal cancers. Methodology: The study included ten of patients with medulloblastoma cancer, where the radiation treatment planning do for the medulloblastoma using two adjacent beams photon-photon and take the possibility of error (0, + 1, + 2,-1,-2 mm) in area between the fields which can Occur during the treatment process and caused of overlap or gap between this beams (hot and cold areas), Statistical analysis was performed on; maximum dose percentage received by the planning target volume (PTV max dose %) and matching beams dose percentage and mean volume of the hot area and the cold area. Results and Discussion: Disclose results of radiotherapy planning technique that two matching beams Photon-Photon, the overlap by 1 mm has been causing significant change in dosage in matching area more increase than the dose prescribed by oncologist this increase up to 10% of the prescribed dose and the volume of this hot area more than 8 cubic cm, with increased fields by 2 mm in the dose has increased by 20% of the dose prescribed. The opposite happens when the fields is reduced to (-1, -2 mm) where we find that dose decrease occurring in the region and there didn’t complete coverage of the area to be treated, causing what is called a gap (the region receives a dose of less than 95%). It reveals the result of adjacent of two beams photon-electron in radiation treatment planning for patients with nasopharynx, that an electron might enable us to reduce the dose to organ at risk (OAR) such as the spinal cord but the overlap between the photon and electron by (1, 2 mm) may cause an increase Hot spot in a dose up to 130% and the volume of hot spot is big relative to the size of the PTV. As to reduce the area by (-1, -2 mm) may result in reduced hot area or may cause a gap or cause a gap with stayed the hot area while because of the use of two adjacent photon and electron

Keywords

Three-dimensional Conformal Radiation Therapy (3DCRT), Medulloblastoma Cancer, Radiotherapy Techniques, Matching Field, Adjacent Beams, Cranio-Spinal Cancer Treatment.
Subscription Login to verify subscription
User
Notifications
Font Size


  • L. W. Brady, C. A. Perez, and D. E. Wazer, Perez and Brady's principles and practice of radiation oncology: Lippincott Williams and Wilkins, 2013.
  • R. P. Symonds, C. Deehan, C. Meredith, and J. A. Mills, Walter and Miller's Textbook of Radiotherapy E-book: Radiation Physics, Therapy and Oncology: Elsevier Health Sciences, 2012.
  • A. Skowrońska-Gardas, M. Chojnacka, M. Morawska-Kaczyńska, D. Perek, and M. Perek-Polnik, "Patterns of failure in children with medulloblastoma treated with 3D conformal radiotherapy," Radiotherapy and oncology, vol. 84, pp. 26-33, 2007.
  • A. J. Raimondi and T. Tomita, "Medulloblastoma in childhood," Pediatric Neurosurgery, vol. 5, pp. 310-328, 1979.
  • K. R. Mani, S. Sapru, K. M. Das, and A. Basu, "A supine craniospinal irradiation technique using moving field junctions," Polish Journal of Medical Physics and Engineering, vol. 22, pp. 79-83, 2016.
  • V. Hernández Masgrau, "Optimization of field matching in external photon beam radiation therapy," 2013.
  • C. B. Saw and D. H. Hussey, "Dosimetric assessment of nonperfectly abutted fields using asymmetric collimators," Medical Dosimetry, vol. 25, pp. 23-26, 2000.
  • V. Hernandez and J. Sempau, "The influence of the field setup on the dosimetry of abutted fields in single‐isocenter half‐beam techniques," Medical physics, vol. 38, pp. 1468-1472, 2011.
  • G. J. Kutcher, L. Coia, M. Gillin, W. F. Hanson, S. Leibel, R. J. Morton, et al., "Comprehensive QA for radiation oncology: report of AAPM radiation therapy committee task group 40," Medical physics, vol. 21, pp. 581-618, 1994.
  • E. E. Klein, J. Hanley, J. Bayouth, F. F. Yin, W. Simon, S. Dresser, et al., "Task Group 142 report: quality assurance of medical accelerators," Medical physics, vol. 36, pp. 4197-4212, 2009.
  • A. Barrett, J. Dobbs, and T. Roques, Practical Radiotherapy Planning Fourth Edition: CRC Press, 2009.
  • G. Christ, D. Denninger, O. S. Dohm, B. Weigel, A. Hönes, and F. Paulsen, "Craniospinal radiotherapy in an advanced technique," Strahlentherapie und Onkologie, vol. 184, pp. 530-535, 2008.
  • K. Mah, C. E. Danjoux, S. Manship, N. Makhani, M. Cardoso, and K. E. Sixel, "Computed tomographic simulation of craniospinal fields in pediatric patients: improved treatment accuracy and patient comfort," International Journal of Radiation Oncology• Biology• Physics, vol. 41, pp. 997-1003, 1998.
  • M. Ahmad and R. Nath, "Three‐dimensional radiotherapy of head and neck and esophageal carcinomas: A monoisocentric treatment technique to achieve improved dose distributions," International journal of cancer, vol. 96, pp. 55-65, 2001.
  • P. C. Lee, "Consistent collimator overlaps in field matching with computer-controlled x-ray collimators," Medical Dosimetry, vol. 22, pp. 59-61, 1997.
  • D. I. Rosenthal, J. McDonough, and A. Kassaee, "The effect of independent collimator misalignment on the dosimetry of abutted half-beam blocked fields for the treatment of head and neck cancer," Radiotherapy and oncology, vol. 49, pp. 273-278, 1998.
  • J. C. Stroom and B. J. Heijmen, "Geometrical uncertainties, radiotherapy planning margins, and the ICRU-62 report," Radiotherapy and oncology, vol. 64, pp. 75-83, 2002.
  • E. Hedin, A. Bäck, and R. Chakarova, "Jaw position uncertainty and adjacent fields in breast cancer radiotherapy," Journal of applied clinical medical physics, vol. 16, pp. 240-251, 2015.

Abstract Views: 239

PDF Views: 0




  • Assessments and Dosimatric Evaluation of Matching Fields Technique in the Treatment Cranio-Spinal Cancers

Abstract Views: 239  |  PDF Views: 0

Authors

Ali Ahmed Abulmajeed
Al-Mustansiriya University, College of Medicine, Iraq
Fezaa Shalal Neda
Dept. of Physiology, Medical Physics Unit, Al-Mustansiriya University, Medical College, Iraq
Hayder Hamza Alabidi
Director Baghdad Center of Radiotherapy and Nuclear Medicine, Iraq

Abstract


Radiotherapy is one of the main methods of cancer treatment (often with chemotherapy and surgery) and is generally assumed to be 50 to 60% of cancer patients will benefit from radiotherapy, where radiation therapy is done using the Linear accelerator device. medulloblastoma, a primitive tumor growing in the cerebellum, is one of the most sensitive tumors in the childhood brain to radiotherapy. The most common malignant tumor in children is cancerous tumor with an overall infection among children aged 0-19 from 16 to 20 percent of all brain tumors in hospitals. Radiotherapy is an essential means of treating these tumors and, after surgery, radiation therapy has a significant impact, This study was conducted to understand the impact of the possibilities that could occur during the process of radiotherapy through systemic and irregular errors when set-up the patient for treatment on the occurrence of cold spots and hot spots and the risk of dose at both the craniospinal at treatment. Objectives: Aim of The Work To evaluate the dosimetry homogeneity abutting junction between photon-photon fields in treatment cranio-spinal cancers. Methodology: The study included ten of patients with medulloblastoma cancer, where the radiation treatment planning do for the medulloblastoma using two adjacent beams photon-photon and take the possibility of error (0, + 1, + 2,-1,-2 mm) in area between the fields which can Occur during the treatment process and caused of overlap or gap between this beams (hot and cold areas), Statistical analysis was performed on; maximum dose percentage received by the planning target volume (PTV max dose %) and matching beams dose percentage and mean volume of the hot area and the cold area. Results and Discussion: Disclose results of radiotherapy planning technique that two matching beams Photon-Photon, the overlap by 1 mm has been causing significant change in dosage in matching area more increase than the dose prescribed by oncologist this increase up to 10% of the prescribed dose and the volume of this hot area more than 8 cubic cm, with increased fields by 2 mm in the dose has increased by 20% of the dose prescribed. The opposite happens when the fields is reduced to (-1, -2 mm) where we find that dose decrease occurring in the region and there didn’t complete coverage of the area to be treated, causing what is called a gap (the region receives a dose of less than 95%). It reveals the result of adjacent of two beams photon-electron in radiation treatment planning for patients with nasopharynx, that an electron might enable us to reduce the dose to organ at risk (OAR) such as the spinal cord but the overlap between the photon and electron by (1, 2 mm) may cause an increase Hot spot in a dose up to 130% and the volume of hot spot is big relative to the size of the PTV. As to reduce the area by (-1, -2 mm) may result in reduced hot area or may cause a gap or cause a gap with stayed the hot area while because of the use of two adjacent photon and electron

Keywords


Three-dimensional Conformal Radiation Therapy (3DCRT), Medulloblastoma Cancer, Radiotherapy Techniques, Matching Field, Adjacent Beams, Cranio-Spinal Cancer Treatment.

References