“…Direct intra-luminal spread down the ureter via the pelvicalyceal collecting system is an uncommon event published only in previous case reports. [2][3][4][5][6][7] Due to its uncommon nature, little is known regarding prognostic role of ureteric involvement of RCC, however urinary collecting system invasion has been shown to be significant. 8,9 This has resulted in pelvicalyceal invasion becoming included in the 2018 American Joint Committee on Cancer (AJCC) RCC staging classification as pT3a disease.…”