Chicago Archbishop Cardinal Francis George is again battling cancer.
According to a statement posted Friday on the Chicago Archdiocese's website, George underwent a procedure to have cancerous cells removed from his kidney and liver on Wednesday.
"His doctors will work with the Cardinal to plan a course of treatment," the statement reads. "The Cardinal will be resting at home this weekend and will be on retreat next week."
The Chicago Tribune notes that George, 75, underwent surgery for bladder cancer six years ago. According to the Chicago Sun-Times, he left Loyola University Medical Center cancer-free after spending 19 days there following surgery.
Earlier this year, George submitted his letter of resignation to the pope, a formality that set into motion the early stages of transitioning the city's archdiocese to a new archbishop.