Measurement of Tumor Hypoxia in Patients With Locally Advanced Cervical Cancer Using Positron Emission Tomography with 18F-Fluoroazomyin Arabinoside.
Int J Radiat Oncol Biol Phys
; 102(4): 1202-1209, 2018 11 15.
Article
em En
| MEDLINE
| ID: mdl-29680257
ABSTRACT
PURPOSE:
To assess cervical tumor hypoxia using the hypoxia tracer 18F-fluoroazomycin arabinoside (18F-FAZA) and compare different reference tissues and thresholds for quantifying tumor hypoxia. METHODS AND MATERIALS Twenty-seven patients with cervical cancer were studied prospectively by positron emission tomography (PET) imaging with 18F-FAZA before starting standard chemoradiation. The hypoxic volume was defined as all voxels within a tumor (T) with standardized uptake values (SUVs) greater than 3 standard deviations from the mean gluteus maximus muscle SUV value (M) or SUVs greater than 1 to 1.4 times the mean SUV value of the left ventricle, a blood (B) surrogate. The hypoxic fraction was defined as the ratio of the number of hypoxic voxels to the total number of tumor voxels.RESULTS:
A 18F-FAZA-PET hypoxic volume could be identified in the majority of cervical tumors (89% when using T/M or T/B > 1.2 as threshold) on the 2-hour static scan. The hypoxic fraction ranged from 0% to 99% (median 31%) when defined using the T/M threshold and from 0% to 78% (median 32%) with the T/B > 1.2 threshold. Hypoxic volumes derived from the different thresholds were highly correlated (Spearman's correlation coefficient ρ between T/M and T/B > 1-1.4 were 0.82-0.91), as were hypoxic fractions (0.75-0.85). Compartmental analysis of the dynamic scans showed k3, the FAZA accumulation constant, to be strongly correlated with hypoxic fraction defined using the T/M (Spearman's ρ=0.72) and T/B > 1.2 thresholds (0.76).CONCLUSIONS:
Hypoxia was detected in the majority of cervical tumors on 18F-FAZA-PET imaging. The extent of hypoxia varied markedly between tumors but not significantly with different reference tissues/thresholds.
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Radioisótopos de Flúor
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Neoplasias do Colo do Útero
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Compostos Radiofarmacêuticos
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Tomografia por Emissão de Pósitrons
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Hipóxia Tumoral
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Nitroimidazóis
Tipo de estudo:
Observational_studies
Limite:
Adult
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Aged
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Aged80
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Female
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Humans
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Middle aged
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article