Oncode Investigator Emile Voest and Oncode researcher Joris van de Haar (both NKI) have shown how by using a DNA test, it is possible to predict which patients with metastatic colon cancer will not benefit from the life-extending chemotherapy regimen FTD/TPI. The results are now published in Nature Medicine.
This can lead to patients being carefully selected, sparing the ones insensitive to this type of chemotherapy. It would also be the first time a genetic test is used in daily patient care to predict the outcome of a specific chemotherapy treatment. The results are now published in Nature Medicine.
“Our findings have a significant and immediate impact on patient care, and show the power of combining real life data, computational science and translational research” says Emile Voest.
In their study, the researchers analysed a large colon cancer patients’ DNA database and what they found is that patients with a specific letter change in the 3 billion-letter long tumor DNA (the "KRAS G12 mutation") do not benefit from the life-prolonging chemotherapy given to terminally ill people with colon cancer. As a result, they decided to re-examine a study from 2015 that demonstrated the efficacy of FTD/TPI chemotherapy against colon cancer. In this study, 800 colon cancer patients received this chemotherapy or a placebo, and the ones with a G12 mutation – a group of over 250 patients - were shown to live just as long when receiving a placebo treatment as they did when receiving chemotherapy - which comes with side effects.
A G12 mutation is common in people with colon cancer, with approximately 25% of all patients presenting with this mutation in the tumor DNA. FTD/TPI is a last-resort treatment for patients with metastatic colon cancer.
The DNA-test is specific to FTD/TPI treatment for colon cancer, and does not cover other forms of chemotherapy. It would be easy to introduce this diagnostic test, as all colon cancer patients are tested for KRAS gene mutations in relation to other treatments.
The scientists hope that these results will motivate research for similar tests that better predict the outcome of chemotherapy in other forms of cancer. To make this possible, the researchers believe that large-scale DNA diagnostics of patients undergoing chemotherapy and other treatments is essential. This data must then be made available for this type of research.
This study was funded by Oncode Institute.