Upper Urinary Tract Urothelial Carcinoma with Intratubular Spread
Judy Sarungbam, Muhammad Choudhury, Ximing Yang, Minghao Zhong. New York Medical College, Valhalla, NY; Northwestern University Feinberg School of Medicine, Chicago, IL
Background: Upper urinary tract urothelial cell carcinomas (UUT-UCs) are uncommon, accounting 7% to 8% of all renal malignancies and representing 5 to 10% of all urothelial tumors. One of well-known and peculiar histopathological finding in UUT-UC is urothelial carcinoma with (retrograde) intratubular spread. However, this special feature has not been systematically studied.
Design: All cases of UUT-UC with nephrouretrectomy from 2006 to 2012 were retrieved from the archives of pathology department. All clinic-pathological information were evaluated with emphasis on the presence of intratubular spread. A cocktail stain which contains immunohistochemistry stains of PAX8 and P63 with PAS was developed and validated to facilitate the study of intratubular spread.
Results: A total of 54consecutive cases of upper urinary tract urothelial carcinomas were identified. The clinical-pathological features of these cases were similar to those that had been published before. Seventeen cases (31.5%) showed intratubular spread confirmed by either H & E stain or the cocktail stains. All of 17 cases (100%) with intratubular spread had tumor involvement of the renal calyx; 14 of 17 (82.4%) cases were high grade urothelial carcinoma; 13 of 17 cases (76.5%) were invasive urothelial carcinoma. According to diverse pathological patterns, we also further classified intratubular spread into 4 different types: typical; pagetoid; florid and intratubular spread with focal invasion.
|Type||Location||# of tubules involvement||Recognizable on H&E||Architecture||Association of tumor grade||Association of invasion|
|Typical||Close to calyx||Few||Yes||Tubular, pseuglandular||High/Low||Invasion and non-invasion|
|Pagetoid||Close to calyx||Few||Maybe||Pagetoid, few cells||High/Low||Invasion and non-invasion|
|Florid||Extended to medulla/cortex junction||More than 10||Yes||Pseuglandular, solid nest with smooth contour||High||Invasion|
|Invasion from tubular spread||May reach cortex||Mult-focal, more than 10 on each focus||Yes||Solid nest with irregular contour||High||Invasion|