Ureteroscopic biopsy of upper tract urothelial carcinoma: Improved diagnostic accuracy and histopathological considerations using a multi-biopsy approach

Purpose: We assessed the diagnostic accuracy of a ureteroscopic multi-biops y approach to upper tract urothelial carcinoma compared with subsequently r esected surgical specimens. Materials and Methods: From 1990 to 1998, 45 upper tract lesions were urete roscopically evaluated and biopsied with 3Fr cup forceps and/or an 11.5Fr r esectoscope before nephroureterectomy or ureterectomy. A definitive diagnos is of urothelial carcinoma was made by biopsy in 40 lesions (89%). Each tum or was histopathologically graded but only staged if the lamina propria wer e uninvolved (Ta), and if the lamina propria were invaded by tumor (T1+). Results: Of the 40 urothelial tumors 16 (40%) were in the renal pelvis, and 8 (20%) in the proximal and 16 (40%) in the distal ureter. Of the lesions 95% were papillary and 65% were grade 2. Ureteroscopic biopsy grade matched surgical pathological grade in 31 of the 40 cases (78%), and was less than surgical pathological grade in the remainder. Lamina propria was detected in 27 of the 40 biopsies, including 21 of the 34 cup (62%) and all 6 resect ion loop (100%) biopsies. Ureteroscopic biopsy staging in 27 cases revealed Ta and T1+ disease in 22 and 5, respectively. In the 5 cases in which uret eroscopic biopsy stage was T1+ surgical pathological stage was also pT1+ (r ange pT1 to pT3). Tumors were pathologically up staged to pT1+ (range pT1 t o pT3) in 10 of the 22 cases (45%) in which ureteroscopic biopsy stage was Ta. Tumor location did not affect diagnostic accuracy. Conclusions: This multi-biopsy ureteroscopic approach provided the tissue d iagnosis of urothelial carcinoma in 89% of cases and predicted exact histop athological grade in 78%. Although it is not accurate as a staging modality , multi-biopsy ureteroscopy may assess lamina propria invasion in two-third s of cases.