By almost every measure, far fewer cancers are being diagnosed during the coronavirus pandemic, whether the decline shows up in screening mammograms and colonoscopies or in other tests ordered after troubling symptoms prompt a doctor’s visit. A research letter published Tuesday in JAMA Network Open notes a steep downward slope in newly identified cases of six common cancer types, based on weekly numbers from Quest Diagnostics. The clinical laboratory’s data add to similar analyses conducted in May and July from the electronic medical records vendor Epic and a July report from the COVID and Cancer Research Network on trends in cancer-related patient encounters.