A blood test could provide hints about cancer return

Researchers have unveiled a blood biopsy that that could help track which patients whose cancer has been treated face higher risks of recurrence. To validate their test, the researchers looked back at samples from 142 patients with breast cancer who had had their blood drawn right after surgery and again a year after their operations. The test scanned the blood for “minimal residual disease,” essentially, evidence that some tumor cells had been left behind. The test did not identify every patient whose cancer returned, and performed better when it had more mutations from the tumor to sniff out. Researchers described their study as a demonstration and are working to improve the test.