Clear Cell Renal Cell Carcinoma with a Ureteral Thrombus

Abstract

Introduction: Cancers of the kidney, arising from either the renal parenchymal tissue or the renal pelvis, is among the 13 commonest types of malignancy globally, accounting for between 3% and 4% of all newly diagnosed cancers. Renal cell carcinoma (RCC) accounts for 85% of all malignant renal neoplasms. We present a rare case of an RCC directly extending into the renal pelvicalyceal system and with a thrombus within the ureter.Case Presentation: A 39-year-old woman presented with a long-standing history of worsening left flank pain, intermittent visible hematuria, and a fullness in the left flank. Apart from an ill-defined left flank mass with pain on palpation, there was nothing remarkable on clinical examination. Contrast-enhanced abdominal CT scan images showed a large, heterogeneously enhancing soft tissue mass arising from the lower pole of the left kidney. The collecting system and the left proximal ureter were poorly visualized. A tentative diagnosis of RCC, cT3aN0M0 was made. Intraoperatively, we identified a large, left lower pole renal mass, displacing the pedicle superiorly. In addition, we found a bulky, dilated proximal ureter. A decision was made intraoperatively to proceed with radical nephrectomy and ureterectomy.Conclusion: We report a rare case of RCC directly invading from the renal pelvis and down the ureter as a thrombus mass, with no microscopic individual tumor implants in the ureter wall, invasion of the renal vein, or invasion of adjacent organs. To our knowledge, only four such cases have been reported in English literature, and as a result, very few theories explaining renal pelvic invasion and direct growth down the ureter have been postulated. This highlights the significance of adding invasion of the pelvicalyceal system as part of the most recent, updated tumor node metastases classification. In future, consideration needs to be given to include the extension of RCC into the ureter and/or bladder.

Renal cell carcinoma with intra-operatively identified encapsulated intra-luminal tumour extension throughout the entire ureter

“…Following literature review, only six previous case reports have been identified. 2–7 These reports do however describe similar histological characteristics. All cases appear to involve extensive pelvicalyceal and renal sinus involvement with an absence of urothelial invasion.…”

“…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.…”

“…10 Terminology regarding intra-ureteric tumour extension requires clearer definition with a distinction to be made from the misnomer ‘tumour thrombus’ as described in existing case reports which should be replaced instead with ‘encapsulated intra-luminal tumour extension’. 2–7…”

KIF20B promotes the progression of clear cell renal cell carcinoma by stimulating cell proliferation

“…According to the investigation, renal tumor occupies the second place in the urogenital system tumors in China, only second to bladder cancer, accounting for nearly 2% adult cancers (Mlot, Szczylik, & Rzepecki, ). ccRCC is a highly metastatic tumor, accounting for about 85% of RCC (John, Aldera, Sinha, & Lazarus, ). Recently, targeted therapy became a promising treatment for ccRCC, and drugs on the basis of several therapeutic targets, such as BAP1 and PBRM1, have been demonstrated by clinical proof (da Costa et al, ).…”

Prevalence of Kidney, Renal Pelvis, and Ureter Cancers in Isfahan Province, Iran

“…The prevalence of RCC has risen steadily and it has the highest mortality (around 40%) among the genitourinary cancers. Its maximum incidence was reported in the sixth decade of life with more frequency in Afro-American people (1)(2)(3). Among men and women, this malignancy takes the tenth and fourteenth places, respectively (4).…”