Dose painting in radiotherapy for head and neck squamous cell carcinoma : value of repeated functional imaging with <script type="math/tex">^{18}F-FDG</script> PET, <script type="math/tex">^{18}F</script>-fluoromisonidazole PET, diffusion-weighted MRI, and dynamic contrast-enhanced MRI

Dirix, Piet; Vandecaveye, Vincent; De Keyzer, Frederik; Stroobants, Sigrid; Hermans, Robert; Nuyts, Sandra

doi:10.2967/JNUMED.109.062638

Publication

Title

Dose painting in radiotherapy for head and neck squamous cell carcinoma : value of repeated functional imaging with $^{18}F-FDG$ PET, $^{18}F$ -fluoromisonidazole PET, diffusion-weighted MRI, and dynamic contrast-enhanced MRI

Author

Dirix, Piet

Vandecaveye, Vincent

De Keyzer, Frederik

Stroobants, Sigrid

Hermans, Robert

Nuyts, Sandra

Abstract

The purpose of this work was to evaluate the potential of functional imaging with 18F-FDG PET, 18F-fluoromisonidazole PET, diffusion-weighted MRI, and dynamic contrast-enhanced MRI to provide an appropriate and reliable biologic target for dose painting in radiotherapy for head and neck squamous cell carcinoma (HNSCC). Methods: Fifteen patients with locally advanced HNSCC, treated with concomitant chemoradiotherapy, were prospectively enrolled in a bioimaging protocol. Sequential PET (18F-FDG and 18F-fluoromisonidazole) and MRI (T1, T2, dynamic enhanced, and diffusion-weighted sequences) were performed before, during, and after radiotherapy. Results: Median follow-up was 30.7 mo (range, 6.356.3 mo); in 7 patients, disease recurred. Disease-free survival correlated negatively with the maximum tissue-to-blood 18F-fluoromisonidazole ratio (T/Bmax) on the baseline 18F-fluoromisonidazole scan (P = 0.04), with the size of the initial hypoxic volume (P = 0.04), and with T/Bmax on the 18F-fluoromisonidazole scan during treatment (P = 0.02). All locoregional recurrences were within the 18F-FDGavid regions on baseline 18F-FDG PET; 3 recurrences mapped outside the hypoxic volume on baseline 18F-fluoromisonidazole PET. Lesions (primary tumor and lymph nodes) where a locoregional recurrence developed during follow-up had significantly lower apparent diffusion coefficients on diffusion-weighted MRI during week 4 of radiotherapy (0.0013 vs. 0.0018 mm2/s, P = 0.01) and at 3 wk after treatment (0.0014 vs. 0.0018 mm2/s, P = 0.01) and a significantly higher initial slope on baseline dynamic enhanced MRI (26.2 vs. 17.5/s, P = 0.03) than did lesions that remained controlled. Conclusion: These results confirm the added value of 18F-FDG PET and 18F-fluoromisonidazole PET for radiotherapy planning of HNSCC and suggest the potential of diffusion-weighted and dynamic enhanced MRI for dose painting and early response assessment.

Language

English

Source (journal)

The Journal of nuclear medicine. - New York

Publication

New York : 2009

ISSN

0161-5505

Volume/pages

50 :7 (2009) , p. 1020-1027

ISI

000272547100010