Short summary

The aim of the present study is to monitor the RAS and RAF plasma mutation dynamics in metastatic colorectal cancer patients receiving standard first line therapy with FOLFIRI), with or without targeted treatment, independent of mutational status in the tumor tissue.

Rationale

Colorectal cancer is a common cancer with around 4900 new cases per year in Denmark. Twenty-five percent have metastatic disease at the time of diagnosis and of the remaining, 50% will later develop incurable disease. Metastatic CRC patients have poor outcomes with a 5-year survival rate of 13% and a median overall survival of six months without treatment.

Standard mutation analyses in clinical practice are made on tissue samples from the primary tumor in order to select patients for treatment with anti-EGFR monoclonal antibodies (anti-EGFR Mabs). Circulating tumor DNA (ctDNA) has become an interesting alternative when studying the relation to cancer survival and prediction of treatment effect. CtDNA is obtained by a minimally invasive blood sample and gives easily accessible information about mutation status, quantification, and tumor heterogeneity. A liquid biopsy makes it possible to monitor mutation dynamics and treatment effect. Recent studies show good concordance between mutated ctDNA analyses and mutation analyses in tumor tissue.

The exact role of RAS and RAF plasma mutations in mCRC has not yet been established, maybe due to multiple alternative signaling pathways and other mutations. The effect of chemotherapy in combination with anti-EGFR treatment on RAS and RAF mutations during treatment is unknown.   

Description of the cohort

metastatic colorectal cancer patients.

Data and biological material

Blood

Collaborating researchers and departments

Department of Oncology, Vejle Hospital

• Associate Professor Lars Henrik Jensen, MD, PhD

Department of Biochemestry, Vejle Hospital

• Molecular biologist Rikke Fredslund Andersen, PhD