Factors related to lymph node sampling at the time of surgery in children, adolescents, and young adults with unilateral non-metastatic renal cell carcinoma.

Renal cell carcinoma (RCC) is rare in the pediatric, adolescent, and young adult (PAYA) population. PAYA patients with RCC have a high rate of lymph node (LN) involvement, regardless of primary tumor size, yet data to guide surgical LN management in this group are limited.

The objective of this study was to determine what factors are associated with LN sampling (protocol adherence) in PAYAs with RCC.

The National Cancer Database (NCDB) between 2004 and 2013 was queried for patients aged ≤30 yrs with non-metastatic, unilateral RCC managed with surgery. Logistic regression analyses were performed to evaluate factors associated with LN sampling.

A total of 2857 patients met study criteria. Pathologically, 2510 (87.8%) patients were Nx, 278 (9.7%) N0, and 69 (2.4%) N1. Older age was associated with omission of LN sampling (odds ration [OR]: 1.065, 95% confidence interval [CI]: 1.04-1.1, P < 0.001). Higher institutional volume (OR: 0.971, 95% CI: 0.96-0.99, P < 0.001), stage 3 tumors (OR: 0.19, 95% CI: 0.11-0.33, P < 0.001), pre-operative clinical node involvement (OR: 0.32, 95% CI: 0.12-0.86, P = 0.024), tumor size >10 cm (OR: 0.27, 95% CI: 0.12-0.57, P = 0.001), and radical nephrectomy (OR: 0.245, 95% CI: 0.16-0.38, P < 0.001) were associated with patients undergoing LN sampling.

Lymph node sampling is performed in <15% of PAYA patients with RCC. Given the higher rate of translocation RCC pathology in younger patients, which leads to a higher prevalence of nodal involvement (especially with small masses), and the subsequent need for aggressive surgical control of disease, LN sampling and protocol adherence are potentially underutilized in this population and may present a unique opportunity for urologists to improve the care of PAYAs. Data from administrative databases are helpful for rare diseases such as PAYA RCC, but comes with limitations such as missing data. There are several factors that could contribute to LN sampling utilization (National comprehensive cancer network (NCCN) or Children's Oncology Group institution designation, surgeon experience, annual volume, specialty, operative approach, etc.) that cannot be further examined using the NCDB.

Pediatric, adolescent, and young adult patients with localized RCC are less likely to undergo surgical LN sampling if they are older, have tumors <10 cm or of less advanced stage, have no pre-operative clinical suspicion of LN involvement, are treated with partial nephrectomy, or are treated at lower volume centers. It appears that approaches from adults with RCC are being applied to PAYAs despite evidence that PAYAs with RCC experience a significant rate of LN involvement even with small tumors.

Journal of pediatric urology. 2019 Feb 01 [Epub ahead of print]

A F Saltzman, W Stokes, J Walker, N G Cost

University of Kentucky, Department of Urology, Lexington, KY, USA., University of Colorado, Department of Radiation Oncology, Aurora, CO, USA., University of Colorado, Department of Surgery, Division of Urology, Children's Hospital of Colorado, Aurora, CO, USA., University of Colorado, Department of Surgery, Division of Urology, Children's Hospital of Colorado, Aurora, CO, USA. Electronic address: .