Technical Considerations for Nephron-Sparing Surgery in Children: What Is Needed to Preserve Renal Units?

Background: Chemotherapy is used preoperatively for children with bilateral Wilms tumor (BWT) or unilateral high-risk Wilms tumor (UHRWT) to promote tumor regression to facilitate renal preservation with nephron-sparing surgery (NSS). In adults, various surgical techniques have been described to preserve renal tissue. Few studies have examined the use of surgical adjuncts in NSS in children with renal tumors.

Methods: We performed a multi-institutional retrospective review of patients with BWT or UHRWT. Patient demographics, tumor size at diagnosis, following neoadjuvant chemotherapy, utilization of surgical adjuncts including intraoperative ultrasound (IOUS), margin status, complications, renal function, and follow-up were recorded.

Results: The cohort comprised 23 patients: 18 BWT, 3 UHRWT, and 2 patients with solitary kidney. Twenty-two of the 23 patients had successful NSS. IOUS was used 19 times, and seven had positive margins after surgery. Cooling/vascular isolation was used six times. At a median follow-up of 18 mo, median estimated glomerular filtration rate Schwartz was 126 mL/min/1.73 m² and median serum creatinine 0.39 mg/dL in the 22 patients who had successful NSS. There have been no tumor recurrences.

Conclusions: In patients with BWT and UHRWT, surgical adjuncts such as cooling/vascular isolation are uncommonly performed. IOUS may be helpful but does not guarantee negative microscopic margins.

Level of evidence: Level 4, Case series with no comparison group.