Bilateral Wilms' Tumor With Different Responses to Preoperative Chemotherapy.

Wilms' tumor (WT) is a common type of primary renal tumor in the pediatric population that can equally affect both sides. Herein, we describe a case of bilateral Wilms' tumor (BWT) in a three-year-old male with different responses to preoperative chemotherapy in the two kidneys. The left kidney mass responded poorly to chemotherapy than the right kidney, which raised the suspicion of coexisting benign disease or congenital anomaly. However, it was ruled out by preoperative nuclear scan and ultrasound-guided frozen section biopsy taken from the left kidney mass. The report of a frozen section on hematoxylin and eosin (H&E) stain was positive for the small blue cell tumor. The patient was managed successfully with a total nephrectomy of the right kidney and nephron-sparing surgery (NSS) on the left kidney. The postoperative period was uneventful and was managed successfully with radiotherapy. Despite many challenges faced in the management of bilateral Wilms' tumor, surgery is the most preferable mode of therapy with chemotherapy and radiotherapy being effective in certain cases. The patient was followed up till no signs of recurrence or metastasis were observed.