XELOCEL 500 mg (Capecitabine tablets) is a prescription oral chemotherapy medication used in the treatment of cancers such as colorectal (colon/rectal) cancer and breast cancer. Capecitabine works by converting to an active anticancer agent inside the body, helping to slow the growth and spread of cancer cells. XELOCEL is taken by mouth under medical supervision and requires regular blood monitoring throughout treatment to check blood counts and organ function.