May 13 (UPI) -- A routine medical physical revealed a small nodule in former President Joe Biden 's prostate, but its cause is unknown. "In a routine physical exam, a small nodule was found in the prostate, which necessitated further evaluation," a Biden spokesperson told ABC News on Tuesday. The nodule might be benign and could have many potential causes, but additional testing is underway to determine if it is harmless or cancerous. Doctors removed a cancerous skin lesion from his chest while