Primary Carcinoma In Situ of the Ureter Without Concurrent Renal Pelvis or Bladder Carcinoma: A Case Report and Literature Review.

Primary carcinoma in situ (CIS) solely affecting the ureter without concurrent involvement of the kidney or bladder is an exceptionally rare condition. This case report presents the clinical management of a 67-year-old male patient with primary ureteral CIS, highlighting the diagnostic workup, surgical approach, and postoperative outcomes. The diagnosis was established through the use of CT and ureteroscopy, leading to the decision for radical laparoscopic nephroureterectomy. Additionally, a comprehensive literature review was conducted to discuss the diagnostic challenges and management options for primary ureteral CIS.