Journal Article

DKFZ-2024-00619

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Clinical Workflow of Cone Beam Computer Tomography-Based Daily Online Adaptive Radiotherapy with Offline Magnetic Resonance Guidance: The Modular Adaptive Radiotherapy System (MARS).

Kim, J.-Y. (First author)DKFZ* ; Tawk, B.DKFZ* ; Knoll, M.DKFZ* ; Hoegen-Saßmannshausen, P.DKFZ* ; Liermann, J.DKFZ* ; Huber, P. E.DKFZ* ; Lifferth, M.DKFZ* ; Lang, C.DKFZ* ; Häring, P.DKFZ* ; Gnirs, R.DKFZ* ; Jäkel, O.DKFZ* ; Schlemmer, H.-P.DKFZ* ; Debus, J.DKFZ* ; Hörner-Rieber, J.DKFZ* ; Weykamp, F. (Last author)DKFZ*

2024
MDPI Basel

This record in other databases:  

Please use a persistent id in citations: doi:10.3390/cancers16061210

Abstract: The Ethos (Varian Medical Systems) radiotherapy device combines semi-automated anatomy detection and plan generation for cone beam computer tomography (CBCT)-based daily online adaptive radiotherapy (oART). However, CBCT offers less soft tissue contrast than magnetic resonance imaging (MRI). This work aims to present the clinical workflow of CBCT-based oART with shuttle-based offline MR guidance.From February to November 2023, 31 patients underwent radiotherapy on the Ethos (Varian, Palo Alto, CA, USA) system with machine learning (ML)-supported daily oART. Moreover, patients received weekly MRI in treatment position, which was utilized for daily plan adaptation, via a shuttle-based system. Initial and adapted treatment plans were generated using the Ethos treatment planning system. Patient clinical data, fractional session times (MRI + shuttle transport + positioning, adaptation, QA, RT delivery) and plan selection were assessed for all fractions in all patients.In total, 737 oART fractions were applied and 118 MRIs for offline MR guidance were acquired. Primary sites of tumors were prostate (n = 16), lung (n = 7), cervix (n = 5), bladder (n = 1) and endometrium (n = 2). The treatment was completed in all patients. The median MRI acquisition time including shuttle transport and positioning to initiation of the Ethos adaptive session was 53.6 min (IQR 46.5-63.4). The median total treatment time without MRI was 30.7 min (IQR 24.7-39.2). Separately, median adaptation, plan QA and RT times were 24.3 min (IQR 18.6-32.2), 0.4 min (IQR 0.3-1,0) and 5.3 min (IQR 4.5-6.7), respectively. The adapted plan was chosen over the scheduled plan in 97.7% of cases.This study describes the first workflow to date of a CBCT-based oART combined with a shuttle-based offline approach for MR guidance. The oART duration times reported resemble the range shown by previous publications for first clinical experiences with the Ethos system.

Keyword(s): Ethos ; MR-guided radiotherapy ; online adaptive radiotherapy

Note: #EA:E050#LA:E050#

---

Contributing Institute(s):

1. E050 KKE Strahlentherapie (E050)
2. E210 KKE Translationale Radioonkologie (E210)
3. E055 KKE Molekulare Radioonkologie (E055)
4. E040 Med. Physik in der Strahlentherapie (E040)
5. E010 Radiologie (E010)
6. DKTK HD zentral (HD01)

Research Program(s):

1. 315 - Bildgebung und Radioonkologie (POF4-315) (POF4-315)

Appears in the scientific report 2024

---

Database coverage:
; ; ; Article Processing Charges ; BIOSIS Previews ; Biological Abstracts ; Clarivate Analytics Master Journal List ; DOAJ Seal ; Ebsco Academic Search ; Essential Science Indicators ; Fees ; IF >= 5 ; JCR ; PubMed Central ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

---