Increased tumor marker- is cancer back or is it something else

My mom is 2 years and 3 months post total hysterectomy for endometrial cancer. This past winter she had a perforated bowel which required her to have a temporary colostomy. She is scheduled to have reversal surgery next month. Her oncologist had sent her for regular follow up blood work and a CT scan but that was delayed because she came down with COVID. She did have the blood work done in April and her tumor marker was 30. She had repeat blood work done on Monday and the result is now 61. It this an indication that the cancer is back or can this just be because of inflammation due to her colostomy surgery?