Extended Lymph Node Sampling During Surgery for Pediatric Renal Tumors Concerning for Malignancy Does Not Increase Postoperative Complication Rates

Purpose: Although Children's Oncology Group renal tumor protocols mandate lymph node sampling during extirpative surgery for pediatric renal tumors, lymph node sampling is often omitted or low yield. Concerns over morbidity associated with extended lymph node sampling have led to hesitancy in adopting a formal lymph node sampling template. We hypothesized that complications in children undergoing lymph node sampling for renal tumors would be rare, and not associated with the number of lymph nodes sampled. Materials and Methods: A single-institution, retrospective review of patients aged 0-18 years undergoing extirpative renal surgery with lymph node sampling for a suspected malignancy between 2005 and 2019 was performed. Patients with 0 or an unknown number of lymph nodes sampled or <150 days of follow-up were excluded. A "clinically significant" complication was defined as any Clavien complication >= III, small-bowel obstruction, chylous ascites, organ injury, or wound infection. The number of lymph nodes sampled and its influence on the odds of experiencing a clinically significant complication was examined. Results: A total of 144 patients met inclusion criteria. Median patient age was 38 months. Twenty-one patients (15%) had a clinically significant complication, the most common of which was ileus/small-bowel obstruction (n=16). In a multivariable analysis, increased lymph node yield was not found to influence the odds of experiencing a clinically significant complication (P = .6). Conclusions: In this cohort, there was no statistically significant difference in clinically significant complications in patients who underwent more extensive lymph node sampling during surgery for a suspected malignant pediatric renal tumor. Future studies on protocol adherence, staging accuracy, and survival trends using a lymph node sampling template in these patients should be performed.