TY - JOUR
T1 - Toward PET/MRI as one-stop shop for radiotherapy planning in cervical cancer patients
AU - Ahangari, Sahar
AU - Hansen, Naja Liv
AU - Olin, Anders Beck
AU - Nøttrup, Trine Jakobi
AU - Ryssel, Heidi
AU - Berthelsen, Anne Kiil
AU - Löfgren, Johan
AU - Loft, Annika
AU - Vogelius, Ivan Richter
AU - Schnack, Tine
AU - Jakoby, Bjoern
AU - Kjaer, Andreas
AU - Andersen, Flemming Littrup
AU - Fischer, Barbara Malene
AU - Hansen, Adam Espe
PY - 2021/8
Y1 - 2021/8
N2 - BACKGROUND: Radiotherapy (RT) planning for cervical cancer patients entails the acquisition of both Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). Further, molecular imaging by Positron Emission Tomography (PET) could contribute to target volume delineation as well as treatment response monitoring. The objective of this study was to investigate the feasibility of a PET/MRI-only RT planning workflow of patients with cervical cancer. This includes attenuation correction (AC) of MRI hardware and dedicated positioning equipment as well as evaluating MRI-derived synthetic CT (sCT) of the pelvic region for positioning verification and dose calculation to enable a PET/MRI-only setup.MATERIAL AND METHODS: 16 patients underwent PET/MRI using a dedicated RT setup after the routine CT (or PET/CT), including eight pilot patients and eight cervical cancer patients who were subsequently referred for RT. Data from 18 patients with gynecological cancer were added for training a deep convolutional neural network to generate sCT from Dixon MRI. The mean absolute difference between the dose distributions calculated on sCT and a reference CT was measured in the RT target volume and organs at risk. PET AC by sCT and a reference CT were compared in the tumor volume.RESULTS: All patients completed the examination. sCT was inferred for each patient in less than 5 s. The dosimetric analysis of the sCT-based dose planning showed a mean absolute error (MAE) of 0.17 ± 0.12 Gy inside the planning target volumes (PTV). PET images reconstructed with sCT and CT had no significant difference in quantification for all patients.CONCLUSIONS: These results suggest that multiparametric PET/MRI can be successfully integrated as a one-stop-shop in the RT workflow of patients with cervical cancer.
AB - BACKGROUND: Radiotherapy (RT) planning for cervical cancer patients entails the acquisition of both Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). Further, molecular imaging by Positron Emission Tomography (PET) could contribute to target volume delineation as well as treatment response monitoring. The objective of this study was to investigate the feasibility of a PET/MRI-only RT planning workflow of patients with cervical cancer. This includes attenuation correction (AC) of MRI hardware and dedicated positioning equipment as well as evaluating MRI-derived synthetic CT (sCT) of the pelvic region for positioning verification and dose calculation to enable a PET/MRI-only setup.MATERIAL AND METHODS: 16 patients underwent PET/MRI using a dedicated RT setup after the routine CT (or PET/CT), including eight pilot patients and eight cervical cancer patients who were subsequently referred for RT. Data from 18 patients with gynecological cancer were added for training a deep convolutional neural network to generate sCT from Dixon MRI. The mean absolute difference between the dose distributions calculated on sCT and a reference CT was measured in the RT target volume and organs at risk. PET AC by sCT and a reference CT were compared in the tumor volume.RESULTS: All patients completed the examination. sCT was inferred for each patient in less than 5 s. The dosimetric analysis of the sCT-based dose planning showed a mean absolute error (MAE) of 0.17 ± 0.12 Gy inside the planning target volumes (PTV). PET images reconstructed with sCT and CT had no significant difference in quantification for all patients.CONCLUSIONS: These results suggest that multiparametric PET/MRI can be successfully integrated as a one-stop-shop in the RT workflow of patients with cervical cancer.
KW - Female
KW - Humans
KW - Magnetic Resonance Imaging
KW - Positron Emission Tomography Computed Tomography
KW - Positron-Emission Tomography
KW - Radiotherapy Dosage
KW - Radiotherapy Planning, Computer-Assisted
KW - Tomography, X-Ray Computed
KW - Uterine Cervical Neoplasms/diagnostic imaging
UR - http://www.scopus.com/inward/record.url?scp=85107813541&partnerID=8YFLogxK
U2 - 10.1080/0284186X.2021.1936164
DO - 10.1080/0284186X.2021.1936164
M3 - Journal article
C2 - 34107847
SN - 0284-186X
VL - 60
SP - 1045
EP - 1053
JO - Acta Oncologica
JF - Acta Oncologica
IS - 8
ER -