Korean J Urol.  2012 Aug;53(8):577-580.

Wilms' Tumor in a Horseshoe Kidney

• Lee SH
• Bae MH
• Choi SH
• Lee JS
• Cho YS
• Joo KJ
• Kwon CH
• Park HJ

Abstract

The incidence of horseshoe kidney is about 1 in 400 cases. The presence of Wilms' tumor with a horseshoe kidney is unusual, and the occurrence of Wilms' tumor in a horseshoe kidney is estimated at 0.4 to 0.9% of all Wilms' tumors. We report the case of a 5-year-old boy who presented with a stage IV Wilms' tumor in a horseshoe kidney. The patient was treated with preoperative chemotherapy followed by surgical resection and adjuvant chemotherapy. This case illustrates the role of preoperative chemotherapy for preserving renal function and aims to highlight the multimodality treatment of Wilms' tumor.

Keyword

Adjuvant chemotherapy; Neoadjuvant therapy; Wilms tumor

MeSH Terms

Chemotherapy, Adjuvant
Humans
Incidence
Kidney
Neoadjuvant Therapy
Preschool Child
Wilms Tumor

Figure

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  FIG. 1 (A) Computed tomography (CT) scan of the abdomen showing a large heterogenous mass arising from the isthmus of a horseshoe kidney with a parenchymal band extending across the midline (before chemotherapy). (B) CT scan of the abdomen after neoadjuvant chemotherapy showing a decrease in tumor size and central necrotic changes.

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  FIG. 2 (A) Computed tomography scan of the chest before chemotherapy showing metastatic small nodules (black arrows). (B) After chemotherapy, the metastatic small nodules disappeared.

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  FIG. 3 Histopathological findings. (A) Grossly, the excised mass originated from the isthmus of the horseshoe kidney and surrounded the lower poles of both kidneys. (B) Microscopic findings. Typical Wilms' tumor with blastemal, epithelial, and stromal components (H&E, ×40).

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  FIG. 4 Follow-up computed tomography scan of the abdomen (coronal view) after the completion of adjuvant chemotherapy in 25 weeks.

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  FIG. 5 Reconstructed computed tomography angiogram showing multiple renal arteries and aberrant vascular supplies (white arrow) to the isthmus and tumor.

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