A new method to estimate doses to the normal tissues after past extended and involved field radiotherapy for Hodgkin lymphoma

TY - JOUR

T1 - A new method to estimate doses to the normal tissues after past extended and involved field radiotherapy for Hodgkin lymphoma

AU - Maraldo, Maja V

AU - Lundemann, Michael

AU - Vogelius, Ivan R

AU - Specht, Lena

N1 - Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

PY - 2015/2/1

Y1 - 2015/2/1

N2 - INTRODUCTION: Reconstruction of radiotherapy (RT) performed decades ago is challenging, but is necessary to address dose-response questions from epidemiological data and may be relevant in re-irradiation scenarios. Here, a novel method to reconstruct extended and involved field RT for patients with Hodgkin lymphoma was used.MATERIALS AND METHODS: For 46 model patients, 29 organs at risk (OARs) were contoured and seven treatment fields reconstructed (mantle, mediastinal, right/left neck, right/left axillary, and spleen field). Extended and involved field RT were simulated by generating RT plans by superpositions of the seven individual fields. The mean (standard deviation) of the 46 individual mean organ doses were extracted as percent of prescribed dose for each field superposition.RESULTS: The estimated mean doses to the OARs from 17 field combinations were presented. The inter-patient variability was found to be a larger contributor to the uncertainty than the field simulation process. The inter-patient variability depended on the OAR and primarily affected the estimates for OARs located at the edge of the RT field.CONCLUSIONS: Dose estimates for 29 OARs were reported from extended and involved field RT. These estimates could be employed when individual reconstruction is not feasible and estimated doses from past treatments are needed.

AB - INTRODUCTION: Reconstruction of radiotherapy (RT) performed decades ago is challenging, but is necessary to address dose-response questions from epidemiological data and may be relevant in re-irradiation scenarios. Here, a novel method to reconstruct extended and involved field RT for patients with Hodgkin lymphoma was used.MATERIALS AND METHODS: For 46 model patients, 29 organs at risk (OARs) were contoured and seven treatment fields reconstructed (mantle, mediastinal, right/left neck, right/left axillary, and spleen field). Extended and involved field RT were simulated by generating RT plans by superpositions of the seven individual fields. The mean (standard deviation) of the 46 individual mean organ doses were extracted as percent of prescribed dose for each field superposition.RESULTS: The estimated mean doses to the OARs from 17 field combinations were presented. The inter-patient variability was found to be a larger contributor to the uncertainty than the field simulation process. The inter-patient variability depended on the OAR and primarily affected the estimates for OARs located at the edge of the RT field.CONCLUSIONS: Dose estimates for 29 OARs were reported from extended and involved field RT. These estimates could be employed when individual reconstruction is not feasible and estimated doses from past treatments are needed.

KW - Adolescent

KW - Adult

KW - Aged

KW - Dose-Response Relationship, Radiation

KW - Female

KW - Hodgkin Disease

KW - Humans

KW - Mediastinum

KW - Middle Aged

KW - Organs at Risk

KW - Radiation Dosage

KW - Radiotherapy Planning, Computer-Assisted

KW - Young Adult

U2 - 10.1016/j.radonc.2015.01.008

DO - 10.1016/j.radonc.2015.01.008

M3 - Journal article

C2 - 25620063

SN - 0167-8140

VL - 114

SP - 206

EP - 211

JO - Radiotherapy & Oncology

JF - Radiotherapy & Oncology

IS - 2

ER -