New research led by the Spanish National Cancer Research Centre and University of Cambridge, in collaboration with startup Tailor Bio, has developed genomic tests using chromosomal instability (CIN) signatures to predict resistance to chemotherapy drugs such as platinum agents, taxanes, and anthracyclines across multiple cancer types. These tests could personalize chemotherapy regimens, minimize exposure to ineffective treatments, and reduce toxicity. The studies analyzed tumor DNA from over 800 patients and demonstrated that CIN patterns correlate with chemoresistance, offering a pathway towards more refined oncology care and cost savings.