Open AccessSignal changes in T2-weighted MRI of liver metastases under bevacizumab—A practical imaging biomarker?
Author(s) -
Johannes Thüring,
Christiane K. Kuhl,
Alexandra Barabasch,
Lea Hitpaß,
Maike Bode,
N Bunting,
Philipp Bruners,
Nils Krämer
Publication year - 2020
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0230553
Subject(s) - bevacizumab , magnetic resonance imaging , medicine , imaging biomarker , nuclear medicine , intensity (physics) , contrast (vision) , biomarker , chemotherapy , radiology , chemistry , physics , quantum mechanics , artificial intelligence , computer science , biochemistry
Objective The purpose of this study was to investigate signal changes in T2-weighted magnetic resonance imaging of liver metastases under treatment with and without bevacizumab-containing chemotherapy and to compare these signal changes to tumor contrast enhancement. Materials and methods Retrospective analysis of 44 patients, aged 36–84 years, who underwent liver magnetic resonance imaging including T2-weighted and dynamic contrast enhancement sequences. Patients received bevacizumab-containing (n = 22) or conventional cytotoxic chemotherapy (n = 22). Magnetic resonance imaging was obtained at baseline and at three follow-ups (on average 3, 6 and 9 months after initial treatment). Three independent readers rated the T2 signal intensity and the relative contrast enhancement of the metastases on a 5-point scale. Results T2 signal intensity of metastases treated with bevacizumab showed a significant (p<0.001) decrease in T2 signal intensity after initial treatment and exhibit compared to conventionally treated metastases significantly ( p <0.001 for each follow-up) hypointense (bevacizumab: 0.70 ± 0.83 before vs. -1.55 ± 0.61, -1.91 ± 0.62, and -1.97 ± 0.52; cytotoxic: 0.73 ± 0.79 before vs. -0.69 ± 0.81, -0.71 ± 0.68, and -0.75 ± 0.65 after 3, 6, and 9 months, respectively). T2 signal intensity was strongly correlated with tumor contrast enhancement (r = 0.71; p <0.001). Intra-observer agreement for T2-signal intensity was substantial ( κ = 0.75). The agreement for tumoral contrast enhancement between the readers was considerably lower ( κ = 0.39). Conclusion Liver metastases exhibit considerably hypointense in T2-weighted imaging after treatment with bevacizumab, in contrast to conventionally treated liver metastases. Therefore, T2-weighted imaging seems to reflect the effect of bevacizumab.