Ontology highlight
ABSTRACT: Objective
Regorafenib demonstrated efficacy in patients with metastatic colorectal cancer (mCRC). Lack of predictive biomarkers, potential toxicities and cost-effectiveness concerns highlight the unmet need for better patient selection.Design
Patients with RAS mutant mCRC with biopsiable metastases were enrolled in this phase II trial. Dynamic contrast-enhanced (DCE) MRI was acquired pretreatment and at day 15 post-treatment. Median values of volume transfer constant (Ktrans), enhancing fraction (EF) and their product KEF (summarised median values of Ktrans× EF) were generated. Circulating tumour (ct) DNA was collected monthly until progressive disease and tested for clonal RAS mutations by digital-droplet PCR. Tumour vasculature (CD-31) was scored by immunohistochemistry on 70 sequential tissue biopsies.Results
Twenty-seven patients with paired DCE-MRI scans were analysed. Median KEF decrease was 58.2%. Of the 23 patients with outcome data, >70% drop in KEF (6/23) was associated with higher disease control rate (p=0.048) measured by RECIST V. 1.1 at 2 months, improved progression-free survival (PFS) (HR 0.16 (95% CI 0.04 to 0.72), p=0.02), 4-month PFS (66.7% vs 23.5%) and overall survival (OS) (HR 0.08 (95% CI 0.01 to 0.63), p=0.02). KEF drop correlated with CD-31 reduction in sequential tissue biopsies (p=0.04). RAS mutant clones decay in ctDNA after 8 weeks of treatment was associated with better PFS (HR 0.21 (95% CI 0.06 to 0.71), p=0.01) and OS (HR 0.28 (95% CI 0.07-1.04), p=0.06).Conclusions
Combining DCE-MRI and ctDNA predicts duration of anti-angiogenic response to regorafenib and may improve patient management with potential health/economic implications.
SUBMITTER: Khan K
PROVIDER: S-EPMC6204951 | biostudies-literature | 2018 Aug
REPOSITORIES: biostudies-literature
Khan Khurum K Rata Mihaela M Cunningham David D Koh Dow-Mu DM Tunariu Nina N Hahne Jens C JC Vlachogiannis George G Hedayat Somaieh S Marchetti Silvia S Lampis Andrea A Damavandi Mahnaz Darvish MD Lote Hazel H Rana Isma I Williams Anja A Eccles Suzanne A SA Fontana Elisa E Collins David D Eltahir Zakaria Z Rao Sheela S Watkins David D Starling Naureen N Thomas Jan J Kalaitzaki Eleftheria E Fotiadis Nicos N Begum Ruwaida R Bali Maria M Rugge Massimo M Temple Eleanor E Fassan Matteo M Chau Ian I Braconi Chiara C Valeri Nicola N
Gut 20170808 8
<h4>Objective</h4>Regorafenib demonstrated efficacy in patients with metastatic colorectal cancer (mCRC). Lack of predictive biomarkers, potential toxicities and cost-effectiveness concerns highlight the unmet need for better patient selection.<h4>Design</h4>Patients with <i>RAS</i> mutant mCRC with biopsiable metastases were enrolled in this phase II trial. Dynamic contrast-enhanced (DCE) MRI was acquired pretreatment and at day 15 post-treatment. Median values of volume transfer constant (K<su ...[more]