A Case of Sigmoid Colon Cancer Recurrence with Intraluminal Ureteral Dissemination

A 74-year-old male patient underwent laparoscopic left nephroureteral surgery for suspected left ureteral carcinoma on follow-up CT after sigmoid colon cancer surgery and lymph node recurrence surgery. Although primary ureteral adenocarcinoma or metastatic ureteral carcinoma was suspected, postoperative histopathological examination and clinical course led to the diagnosis of intraluminal ureteral dissemination of sigmoid colon cancer. Postoperative intraluminal ureteral recurrence of colorectal cancer is extremely rare. This symptom should be ruled out after sigmoid colon cancer surgery.