{Reference Type}: Case Reports {Title}: Endoscopic Ablation of Upper Tract Urothelial Carcinoma: A Report of Two Cases with Long Disease Recurrence-Free Periods. {Author}: Yamane H;Honda M;Shimizu R;Teraoka S;Kimura Y;Yumioka T;Iwamoto H;Morizane S;Hikita K;Takenaka A; {Journal}: Yonago Acta Med {Volume}: 65 {Issue}: 2 {Year}: May 2022 {Factor}: 1.371 {DOI}: 10.33160/yam.2022.05.005 {Abstract}: Upper tract urothelial carcinoma (UTUC) is a relatively rare disease that accounts for 5% to 10% of all urothelial carcinomas (UCs). Radical nephroureterectomy (RNU) with a bladder cuff is the current gold standard for the management of UTUC; however, endoscopic ablation is also an option for low-risk UTUC to preserve kidney function. Herein, we present two cases of solitary kidney with a right lower ureteral tumor. Both patients underwent left RNU in the past. An 82-year-old man with a right ureteral tumor whose histopathological examination revealed low-grade UC. Laser ablation was performed with ureteroscopy, and there was no recurrence for 7 years after treatment. A 67-year-old woman with a right lower ureteral tumor whose histopathological examination also revealed low-grade UC. Laser ablation was performed, and there was no recurrence for 5 years after the treatment. We closely followed-up our two patients after RNU. This allowed for early detection of tumor recurrence, after which we could perform laser ablation therapy.