Urine sensors could replace needles for cancer monitoring

This study tested a new way to monitor chemotherapy effects in 16 people with advanced colorectal cancer. Instead of repeated blood draws or scans, researchers measured special substances in urine samples collected daily before and after treatment. The goal was to see if these urine markers could track cancer activity non-invasively. The study was small and observational, so it does not prove the method works yet, but it lays groundwork for simpler cancer monitoring.