Early treatment response evaluation using FET PET compared to MRI in glioblastoma patients at first progression treated with bevacizumab plus lomustine.
Eur J Nucl Med Mol Imaging
; 45(13): 2377-2386, 2018 12.
Article
en En
| MEDLINE
| ID: mdl-29982845
ABSTRACT
BACKGROUND:
The goal of this prospective study was to compare the value of both conventional MRI and O-(2-18F-fluoroethyl)-L-tyrosine (FET) PET for response evaluation in glioblastoma patients treated with bevacizumab plus lomustine (BEV/LOM) at first progression.METHODS:
After chemoradiation with concomitant and adjuvant temozolomide, 21 IDH wild-type glioblastoma patients at first progression (age range, 33-75 years; MGMT promoter unmethylated, 81%) were treated with BEV/LOM. Contrast-enhanced MRI and FET-PET scans were performed at baseline and after 8-10 weeks. We obtained FET metabolic tumor volumes (MTV) and tumor/brain ratios. Threshold values of FET-PET parameters for treatment response were established by ROC analyses using the post-progression overall survival (OS) ≤/>9 months as the reference. MRI response assessment was based on RANO criteria. The predictive ability of FET-PET thresholds and MRI changes on early response assessment was evaluated subsequently concerning OS using uni- and multivariate survival estimates.RESULTS:
Early treatment response as assessed by RANO criteria was not predictive for an OS>9 months (P = 0.203), whereas relative reductions of all FET-PET parameters significantly predicted an OS>9 months (P < 0.05). The absolute MTV at follow-up enabled the most significant OS prediction (sensitivity, 85%; specificity, 88%; P = 0.001). Patients with an absolute MTV below 5 ml at follow-up survived significantly longer (12 vs. 6 months, P < 0.001), whereas early responders defined by RANO criteria lived only insignificantly longer (9 vs. 6 months; P = 0.072). The absolute MTV at follow-up remained significant in the multivariate survival analysis (P = 0.006).CONCLUSIONS:
FET-PET appears to be useful for identifying responders to BEV/LOM early after treatment initiation.Palabras clave
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Tirosina
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Imagen por Resonancia Magnética
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Glioblastoma
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Tomografía de Emisión de Positrones
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Bevacizumab
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Lomustina
Tipo de estudio:
Observational_studies
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Prognostic_studies
/
Risk_factors_studies
Límite:
Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Eur J Nucl Med Mol Imaging
Asunto de la revista:
MEDICINA NUCLEAR
Año:
2018
Tipo del documento:
Article
País de afiliación:
Alemania