Pope Leo XIV is set to undergo surgery to remove a lung nodule, a procedure that will determine if the lesion is malignant. The Vatican has canceled all his audiences through Oct. 20. The pope revealed the nodule's discovery during his Sunday noon prayer, emphasizing its early detection. Experts say the surgery, which includes a biopsy, is minimally invasive and carries a low risk. If the nodule is cancerous, the prognosis is excellent due to early removal. Leo's openness about his health is a shift from the Vatican's traditionally guarded approach to papal health issues.