BACKGROUND AND PURPOSE: During cervical cancer treatment, target volumes change position and shape due to organ motion and tumour regression. An MRI-accelerator will provide information on these changes by online magnetic resonance imaging (MRI) guidance throughout each treatment fraction. The purpose of this intensity-modulated radiation therapy (IMRT) planning study is to assess the benefit of online MRI guidance in healthy tissue sparing. MATERIALS AND METHODS: Weekly MRI scans of 11 cervical cancer patients were used. We created four IMRT plans per patient, based on these weekly MRI scans, to simulate an online-IMRT approach. We applied a primary and nodal planning target volume (PTV) margin of 4 mm. As reference, we created an IMRT plan based on the pre-treatment MRI scan (pre-IMRT) using a primary and nodal PTV margin of 15 and 10 mm. The weekly defined bladder, rectum, bowel, and sigmoid contours were evaluated on the online-IMRT and pre-IMRT dose distributions at six dose levels (V10(Gy), V20(Gy), V30(Gy), V40(Gy), V42.8(Gy), and V45(Gy)). RESULTS: Online-IMRT compared to pre-IMRT significantly reduced the volume of healthy tissue irradiated to all dose levels, except V10(Gy). CONCLUSIONS: Online MRI guidance reduces healthy tissue involvement in patients with cervical cancer.
BACKGROUND AND PURPOSE: During cervical cancer treatment, target volumes change position and shape due to organ motion and tumour regression. An MRI-accelerator will provide information on these changes by online magnetic resonance imaging (MRI) guidance throughout each treatment fraction. The purpose of this intensity-modulated radiation therapy (IMRT) planning study is to assess the benefit of online MRI guidance in healthy tissue sparing. MATERIALS AND METHODS: Weekly MRI scans of 11 cervical cancerpatients were used. We created four IMRT plans per patient, based on these weekly MRI scans, to simulate an online-IMRT approach. We applied a primary and nodal planning target volume (PTV) margin of 4 mm. As reference, we created an IMRT plan based on the pre-treatment MRI scan (pre-IMRT) using a primary and nodal PTV margin of 15 and 10 mm. The weekly defined bladder, rectum, bowel, and sigmoid contours were evaluated on the online-IMRT and pre-IMRT dose distributions at six dose levels (V10(Gy), V20(Gy), V30(Gy), V40(Gy), V42.8(Gy), and V45(Gy)). RESULTS: Online-IMRT compared to pre-IMRT significantly reduced the volume of healthy tissue irradiated to all dose levels, except V10(Gy). CONCLUSIONS: Online MRI guidance reduces healthy tissue involvement in patients with cervical cancer.
Authors: Chavelli M Kensen; Tomas M Janssen; Anja Betgen; Lisa Wiersema; Femke P Peters; Peter Remeijer; Corrie A M Marijnen; Uulke A van der Heide Journal: Radiat Oncol Date: 2022-06-21 Impact factor: 4.309
Authors: Peter S N van Rossum; Richard van Hillegersberg; Frederiek M Lever; Irene M Lips; Astrid L H M W van Lier; Gert J Meijer; Maarten S van Leeuwen; Marco van Vulpen; Jelle P Ruurda Journal: Eur Radiol Date: 2013-02-13 Impact factor: 5.315
Authors: Tilman Bostel; Asja Pfaffenberger; Stefan Delorme; Constantin Dreher; Gernot Echner; Peter Haering; Clemens Lang; Mona Splinter; Frederik Laun; Marco Müller; Oliver Jäkel; Jürgen Debus; Peter E Huber; Florian Sterzing; Nils H Nicolay Journal: Strahlenther Onkol Date: 2018-01-18 Impact factor: 3.621