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ADVANCES IN SOLID TUMOR RESEARCH
Session: Advances in solid tumor research
LECTURES
ctDNA biomarker detection in patients with colorectal cancer
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Remond J.A. Fijneman
1 The Netherlands Cancer Institute, Department of Pathology,
Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
r.fijneman@nki.nl
Background: Biomarkers reflect disease biology and have the potential to improve diagnosis, prognosis,
prediction and monitoring of treatment response. Cell-free circulating tumor DNA (ctDNA) is an example
of a very promising biomarker. Our studies aim to investigate the clinical utility of ctDNA testing to improve
disease management of patients with colorectal cancer (CRC). Patients and methods: We make use of
multicenter clinical trials and clinical studies organized within the Prospective Dutch CRC cohort PLCRC
(www.PLCRC.nl) to arrange informed consent and collect clinical data, tissue and blood samples. Industrial
grade ctDNA biomarker assays are developed and provided by private partners. In the COIN project, ctDNA
study data is used for early health technology assessment towards scenarios for reimbursement and
approval by authorities. Results: We succeeded to establish the efficient logistics for multicenter collection
of clinical samples and data. So far, more than 1500 CRC patients were accrued with stage II (PLCRC-
MEDOCC and -CrEATE), stage III (PLCRC-PROVENC3) and stage IV (PLCRC-ORCA, CAIRO5, CAIRO6) disease.
We compared diagnostic strategies how to apply liquid biopsy ctDNA testing as a predictive biomarker to
determine eligibility for anti-EGFR therapy in patients with liver metastases. We currently investigate ctDNA
prognostic value in post-surgery blood samples to better stratify stage II and stage III colon cancer patients
for adjuvant chemotherapy. Conclusions: Successful translation of disease biology into new diagnostic
applications requires solving scientific, ethical, legal, societal, financial and regulatory problems.
Coordinated and collaborative (inter)national initiatives to establish a clinical framework for biomarker
validation are instrumental to pave the road towards clinical implementation.
Keywords: colorectal cancer; biomarkers; cell-free circulating tumor DNA
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