Dataset Information

Effect of radiochemotherapy on T2* MRI in HNSCC and its relation to FMISO PET derived hypoxia and FDG PET.

ABSTRACT:

Background

To assess the effect of radiochemotherapy (RCT) on proposed tumour hypoxia marker transverse relaxation time (T2*) and to analyse the relation between T2* and ¹⁸F-misonidazole PET/CT (FMISO-PET) and ¹⁸F-fluorodeoxyglucose PET/CT (FDG-PET).

Methods

Ten patients undergoing definitive RCT for squamous cell head-and-neck cancer (HNSCC) received repeat FMISO- and 3 Tesla T2*-weighted MRI at weeks 0, 2 and 5 during treatment and FDG-PET at baseline. Gross tumour volumes (GTV) of tumour (T), lymph nodes (LN) and hypoxic subvolumes (HSV, based on FMISO-PET) and complementary non-hypoxic subvolumes (nonHSV) were generated. Mean values for T2* and SUVmean FDG were determined.

Results

During RCT, marked reduction of tumour hypoxia on FMISO-PET was observed (T, LN), while mean T2* did not change significantly. At baseline, mean T2* values within HSV-T (15?±?5 ms) were smaller compared to nonHSV-T (18?±?3 ms; p =?0.051), whereas FDG SUVmean (12?±?6) was significantly higher for HSV-T (12?±?6) than for nonHSV-T (6?±?3; p =?0.026) and higher for HSV-LN (10?±?4) than for nonHSV-LN (5?±?2; p ??0.011). Correlation between FMISO PET and FDG PET was higher than between FMSIO PET and T2* (R² for GTV-T (FMISO/FDG)?=?0.81, R² for GTV-T (FMISO/T2*)?=?0.32).

Conclusions

Marked reduction of tumour hypoxia between week 0, 2 and 5 found on FMISO PET was not accompanied by a significant T2*change within GTVs over time. These results suggest a relation between tumour oxygenation status and T2* at baseline, but no simple correlation over time. Therefore, caution is warranted when using T2* as a substitute for FMISO-PET to monitor tumour hypoxia during RCT in HNSCC patients.

Trial registration

DRKS, DRKS00003830 . Registered 23.04.2012.

SUBMITTER: Wiedenmann N

PROVIDER: S-EPMC6114038 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Publications

Effect of radiochemotherapy on T2* MRI in HNSCC and its relation to FMISO PET derived hypoxia and FDG PET.

Wiedenmann Nicole N Bunea Hatice H Rischke Hans C HC Bunea Andrei A Majerus Liette L Bielak Lars L Protopopov Alexey A Ludwig Ute U Büchert Martin M Stoykow Christian C Nicolay Nils H NH Weber Wolfgang A WA Mix Michael M Meyer Philipp T PT Hennig Jürgen J Bock Michael M Grosu Anca L AL

Radiation oncology (London, England) 20180829 1

<h4>Background</h4>To assess the effect of radiochemotherapy (RCT) on proposed tumour hypoxia marker transverse relaxation time (T2*) and to analyse the relation between T2* and <sup>18</sup>F-misonidazole PET/CT (FMISO-PET) and <sup>18</sup>F-fluorodeoxyglucose PET/CT (FDG-PET).<h4>Methods</h4>Ten patients undergoing definitive RCT for squamous cell head-and-neck cancer (HNSCC) received repeat FMISO- and 3 Tesla T2*-weighted MRI at weeks 0, 2 and 5 during treatment and FDG-PET at baseline. Gros ...[more]

PMID: 30157883

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Dataset Information

Effect of radiochemotherapy on T2* MRI in HNSCC and its relation to FMISO PET derived hypoxia and FDG PET.

Background

Methods

Results

Conclusions

Trial registration

Publications

Effect of radiochemotherapy on T2* MRI in HNSCC and its relation to FMISO PET derived hypoxia and FDG PET.

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