Transitional Cell Carcinoma in the Horseshoe Kidney: Report of 3 Cases and Review of the Literature

Abstract

Summary— Horseshoe kidney is the most frequent abnormality of renal fusion and can be complicated by urinary stasis, resulting in infection and calculus formation. Adenocarcinoma is not uncommon, but transitional cell carcinoma of the renal pelvis occurs more frequently in horseshoe than in non‐fused kidneys. Twenty‐two cases of carcinoma of the renal pelvis of horseshoe kidneys have been reported. We add 3 more.

Clear cell sarcoma of kidney involving a horseshoe kidney and harboring EGFR internal tandem duplication

“…Horseshoe kidney (HSK) is one of the most common developmental disorders of the genitourinary system, with an estimated incidence of approximately 1 in 400 in the United States . Primary neoplasms have been reported to arise in approximately 12% of HSKs, with Wilms tumor (WT) being the most common among children.…”

“…2). Additional findings included gains of several chromosomes (chromosomes2,5,7,8,9,11,12,17, 19, 20, and 21), with no chromosomal losses detected. Further IHC staining for EGFR was performed with the BenchMark ULTRA slide stainer (Ventana Medical Systems, Inc.) on a 4-m-thick formalin-fixed, paraffin-embedded tissue section using anti-EGFR antibody (incubated for 60 min at 37 • C; clone 31G7; catalog number 081205, Thermo Fisher Scientific).…”

Incidence of Tumoural Pathology in Horseshoe Kidneys

“…The incidence of the tumorous pathology in HK is quite low: 144 cases have been described up to date in the English and in the Spanish literature. On the contrary, HK seems to have a significantly higher risk of developing a nephroblastoma [2] and an up to 3–4 times higher risk of developing an urothelium tumour [3] than normal kidneys, due to possible embryopathogenic mechanisms and the chronic obstruction of urine, respectively. The most common tumour is renal adenocarcinoma, as in other kidneys.…”

Horseshoe Kidney: A Fusion Anomaly

“…Surgical division of the isthmus improves the function of the kidneys whether there is any apparent pathology or not. 5 Numerous other pathologies have been described in horseshoe kidney [6][7][8][9] but correlation of causation of pathologies with this anomaly has not been established. 10,11 Literature also describes numerous other anomalies associated with horseshoe kidney 3,12 ; in our case no other major anomaly was found.…”