% IMPORTANT: The following is UTF-8 encoded. This means that in the presence % of non-ASCII characters, it will not work with BibTeX 0.99 or older. % Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or % “biber”. @ARTICLE{Serrano:275647, author = {C. Serrano and S. Bauer$^*$ and D. Gómez-Peregrina and Y.-K. Kang and R. L. Jones and P. Rutkowski and O. Mir and M. C. Heinrich and W. D. Tap and K. Newberry and A. Grassian and H. Shi and S. Bialick and P. Schöffski and M. A. Pantaleo and M. von Mehren and J. C. Trent and S. George}, title = {{C}irculating tumor {DNA} analysis of the phase {III} {VOYAGER} trial: {KIT} mutational landscape and outcomes in patients with advanced gastrointestinal stromal tumor treated with avapritinib or regorafenib.}, journal = {Annals of oncology}, volume = {34}, number = {7}, issn = {0923-7534}, address = {Amsterdam [u.a.}, publisher = {Elsevier}, reportid = {DKFZ-2023-00835}, pages = {615-625}, year = {2023}, note = {2023 Jul;34(7):615-625}, abstract = {The current treatment paradigm of imatinib-resistant metastatic gastrointestinal stromal tumor (GIST) does not incorporate KIT/PDGFRA genotypes in therapeutic drug sequencing, except for PDGFRA exon 18-mutant GIST that are indicated for avapritinib treatment. Here, ctDNA sequencing was used to analyze plasma samples prospectively collected in the phase III VOYAGER trial to understand how the KIT/PDGFRA mutational landscape contributes to tyrosine-kinase inhibitor (TKI) resistance and to determine its clinical validity and utility.VOYAGER (N=476) compared avapritinib with regorafenib in patients with KIT/PDGFRA-mutant GIST previously treated with imatinib and 1 or 2 additional TKIs (NCT03465722). KIT/PDGFRA ctDNA mutation profiling of plasma samples at baseline and end-of-treatment was assessed with 74-gene Guardant360® CDx. Molecular subgroups were determined and correlated with outcomes.386/476 patients with KIT/PDGFRA-mutant tumors underwent baseline (pre-trial treatment) ctDNA analysis; 196 received avapritinib, and 190 received regorafenib. KIT and PDGFRA mutations were detected in $75.1\%$ and $5.4\%,$ respectively. KIT resistance mutations were found in the activation loop (A-loop; $80.4\%)$ and ATP-binding pocket (ATP-BP; $40.8\%);$ $23.4\%$ had both. An average of 2.6 KIT mutations were detected per patient; $17.2\%$ showed 4-14 different KIT resistance mutations. Of all pathogenic KIT variants, $28.0\%$ were novel, including alterations in exons/codons previously unreported. PDGFRA mutations showed similar patterns. ctDNA-detected KIT ATP-BP mutations negatively prognosticated avapritinib activity, with a median progression-free survival (mPFS) of 1.9 versus 5.6 months for regorafenib. mPFS for regorafenib did not vary regardless of the presence or absence of ATP-BP/A-loop mutants and was greater than mPFS with avapritinib in this population. Secondary KIT ATP-BP pocket mutation variants, particularly V654A, were enriched upon disease progression with avapritinib.CtDNA sequencing efficiently detects KIT/PDGFRA mutations and prognosticates outcomes in patients with TKI-resistant GIST treated with avapritinib. ctDNA analysis can be used to monitor disease progression and provide more personalized treatment.}, keywords = {Avapritinib (Other) / GIST (Other) / KIT (Other) / PDGFRA (Other) / ctDNA (Other) / regorafenib (Other)}, cin = {ED01}, ddc = {610}, cid = {I:(DE-He78)ED01-20160331}, pnm = {899 - ohne Topic (POF4-899)}, pid = {G:(DE-HGF)POF4-899}, typ = {PUB:(DE-HGF)16}, pubmed = {pmid:37105265}, doi = {10.1016/j.annonc.2023.04.006}, url = {https://inrepo02.dkfz.de/record/275647}, }