Dataset Information

Signal changes in T2-weighted MRI of liver metastases under bevacizumab-A practical imaging biomarker?

ABSTRACT:

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 (? = 0.75). The agreement for tumoral contrast enhancement between the readers was considerably lower (? = 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.

SUBMITTER: Thuring J

PROVIDER: S-EPMC7108712 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Publications

Signal changes in T2-weighted MRI of liver metastases under bevacizumab-A practical imaging biomarker?

Thüring Johannes J Kuhl Christiane Katharina CK Barabasch Alexandra A Hitpass Lea L Bode Maike M Bünting Nina N Bruners Philipp P Krämer Nils Andreas NA

PloS one 20200331 3

<h4>Objective</h4>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.<h4>Materials and methods</h4>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 bevaciz ...[more]

PMID: 32231380

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Dataset Information

Signal changes in T2-weighted MRI of liver metastases under bevacizumab-A practical imaging biomarker?

Objective

Materials and methods

Results

Conclusion

Publications

Signal changes in T2-weighted MRI of liver metastases under bevacizumab-A practical imaging biomarker?

Similar Datasets

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