Seokhwan Bang

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1. Introduction Kidney cancer is a disease that can be treated relatively easily if detected in its early stages, such as T1a (<4 cm), but the survival rate decreases as the disease progresses [1,2]. Therefore, rapid and accurate diagnosis is very important in the treatment of kidney cancer; however, it is not easy. It is particularly difficult to accurately predict the type and subtype of the lesion when the renal mass is small.

1. Introduction Urothelial carcinoma is the fourth most common cancer, and 5~10% of urothelial carcinomas are located in the upper tract [1,2]. The gold standard for the treatment of upper tract urothelial carcinoma is nephroureterectomy (NUx) with excision of the ipsilateral ureteral orifice and a bladder cuff [3,4]. The technique of laparoscopic NUx was first introduced in 1991 [5], and a clinical series was reported in 1993 [6].