Poster (Other)

DKFZ-2025-02746

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png 3870 Towards MRI-based biomarkers for prognostic response assessment of adaptive radiotherapy in non-small cell lung cancer (NSCLC)

Niklas, M. (Corresponding author)DKFZ* ; Giske, K.DKFZ* ; Gnirs, R.DKFZ* ; Sedlaczek, O.DKFZ* ; Jende, J.DKFZ* ; Ziener, C.DKFZ* ; Saßmannshausen, P. H.DKFZ* ; Huber, P.DKFZ* ; Regnery, S. ; Hörner-Rieber, J. ; Jäkel, O.DKFZ* ; Schlemmer, H.-P.DKFZ* ; Debus, J.DKFZ* ; Weykamp, F.DKFZ*

2025

Abstract: Towards MRI-based biomarkers for prognostic response assessment of adaptive radiotherapy in non-small cell lung cancer (NSCLC)Introduction:Daily online adaptive radiotherapy (oART) offers superior target coverage whilst sparing organs at risk. Due to its superior soft tissue contrast, magnetic resonance imaging (MRI) might further improve oART. Moreover, MRI can additionally provide functional imaging, e.g. diffusion weighted imaging (DWI) which could allow for early tumor response assessment and functions as the basis of future dose tailoring approaches. Evidence for oART in lung cancer is scarce and to the best of our knowledge non-existent for the combination with offline diagnostic MR-guidance.Methods:From June 2023 to February 2024, 13 patients with locally advanced NSCLC underwent chemoradiotherapy (CRT) at the ETHOS linear accelerator (Varian Medical Systems) for daily oART. All patients received weekly 3T MRI (T1, T2, DWI) in treatment position using a shuttle (CQ Medical Limited), which is utilized for plan adaptation (i.e. offline diagnostic MR-guidance). Target volumes were segmented in the daily cone beam computed tomography aided by the weekly co-registered MRI sequences. Results:The 3dim volume change of the NSCLC could be quantified by different MRI sequences (Figure 1). First results showed an increase in the calculated mean apparent diffusion coefficient (ADC) in the 3dim tumor volume of NSCLC in parallel to a volume shrinkage characterized by T2 imaging, which could be interpreted as successful response to CRT by the adaptive ETHOS workflow. The ADC map could thus be a potential morphological and functional biomarker for prognostic response assessment next to dynamic contrast-enhanced MRI. Still, due to artifacts, arising from respiratory and cardiac movements as well as differences in the susceptibility of neighboring organs, the target volume might not be defined by the DWI MRI alone. It could yet serve for strategy adaptation in oART. Sub-regions of very low ADC values (corresponding to high cell density) in the heterogenous ADC map of the tumor volume were observed and could act as potential target volumes in boost strategies in oART. Conclusion:This ongoing study will address the characterization of NSCLC by offline 3T MRI. It will also address the value of thoracic DWI for defining morphological and functional biomarkers for possible boost strategies in oART, early risk stratification and for prognosis assessment of NSCLC.

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Contributing Institute(s):

1. E010 Radiologie (E010)
2. E040 Med. Physik in der Strahlentherapie (E040)
3. E055 KKE Molekulare Radioonkologie (E055)
4. E050 KKE Strahlentherapie (E050)

Research Program(s):

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

Appears in the scientific report 2025

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Database coverage:
; BIOSIS Previews ; Biological Abstracts ; Clarivate Analytics Master Journal List ; Current Contents - Clinical Medicine ; Ebsco Academic Search ; Essential Science Indicators ; IF >= 5 ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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