Page 19 - 18F-FDG PET as biomarker in aggressive lymphoma; technical and clinical validation

development and maintenance of the shared PETRA database our research group collaborates with Lygature’s TraIT (Translational Research IT) project, currently transitioning into HEALTH-RI infrastructure [49]. This PETRA database consisting of individual patient data enabled us to investigate the above mentioned research questions about the optimal timing and response criteria for interim [18F] FDG PET and to perform necessary steps to validate interim [18F]FDG PET as a biomarker of response in first‐line DLBCL treatment using a meta‐analysis of individual patient data. A KWF/Alpe d’Huzes grant was obtained for performing this research (VU 2012-5848).
HOVON-84 study
HOVON-84 was the first international randomized phase III clinical trial where an observational interim [18F]FDG PET scan was made after 4 cycles of R-CHOP14. This study included 574 newly diagnosed CD20 positive DLBCL patients (18‐80 years) with Ann Arbor stage II‐IV. Interim [18F]FDG PET and CT were performed after 4 cycles of standard R‐CHOP14 or rituximab intensified R-CHOP14, without treatment modification based on the interim scan. Rituximab intensification did not lead to improvement of outcome in patients with untreated DLBCL [50]. Thus, the HOVON-84 study provides excellent data to determine which interim [18F]FDG PET response criteria perform best in this clinical setting. For this purpose, we included the HOVON-84 study in the PETRA database.
Central PET review
For the HOVON-84 study a central [18F]FDG PET review of all interim and end-of-treatment [18F]FDG PET scans was performed. Nuclear medicine physicians who are members from the HOVON imaging group performed this review [51]. An imaging platform for this study was setup in Keosys (Imagys platform) to perform the review in a similar digital environment [52]. This central PET review procedure allowed our research group to investigate the interobserver agreement of interim and end-of-treatment [18F]FDG PET assessment with the Deauville 5-point scale. With HOVON-84 being the first HOVON study that
General introduction
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