Tumors, a test tells in advance who will not respond to chemotherapy

A test that analyzes a series of tumor markers in a combined manner is able to identify cancer patients who are more likely to not respond to chemotherapy. The test was developed by researchers from the Centro Nacional de Investigaciones Oncológicas in Madrid, together with colleagues from the University of Cambridge and the university spin-off Tailor Bio, who illustrated its characteristics in the journal Nature Genetics.

"Chemotherapy is good for some patients, but it's not effective for everyone. Between 20 and 50 percent of cancer patients don't respond to these drugs," says study coordinator Geoff Macintyre. Researchers have recently helped identify biomarkers that signal the presence of chromosomal instability, an abnormality - common in cancer - that causes entire chromosomes or parts of them to be duplicated, missing or badly assembled. They also found that some of these appear to be associated with response to chemotherapy.

In the new study, the team verified the presence of these markers in 840 patients with different types of cancer (breast, prostate, ovarian and sarcomas) who had undergone chemotherapy, relating it to the effectiveness of the treatment. Patients with positivity for the markers had up to 7 times higher risk of not responding to treatment, even in the absence of other risk indicators. "We were able to demonstrate the effectiveness of our resistance biomarkers for three types of chemotherapy: platinum derivatives, taxanes and anthracyclines," added Macintyre, who anticipated that the team is working on a larger trial to confirm the discovery and evaluate its potential application in other cancers.

If the results are positive, the researchers conclude, it will be possible, on the one hand, to spare the side effects of chemotherapy for those who do not benefit from it, and on the other, to immediately direct these patients towards treatments that have a greater chance of success.