Department of Surgery, Division of Urology, University of Colorado School of Medicine, Aurora, CO, USA.
Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, CO, USA.
J Pediatr Urol. 2018 Apr;14(2):161.e1-161.e8. doi: 10.1016/j.jpurol.2017.09.025. Epub 2017 Oct 31.
There is controversy about the role of lymph node (LN) sampling or dissection in the management of favorable histology (FH) Wilms tumor (WT), specifically how it performed and how it may impact survival.
The objective of this study was to analyze factors affecting LN sampling patterns and the impact of LN yield and density (number of positive LNs/LNs examined) on overall survival (OS) in patients with advanced-stage favorable histology Wilms tumor (FHWT).
The National Cancer Database (NCDB) was queried for patients with FHWT during 2004-2013. Demographic, clinical and OS data were abstracted for those who underwent surgical resection. Poisson regression was performed to analyze how factors influenced LN yield. Patients with positive LNs had LN density calculated and were further analyzed.
A total of 2340 patients met criteria, with a median age at diagnosis of 3 years (range 0-78 years). The median number of LNs examined was three (range 0-87). Lymph node yield was affected by age, race, insurance, tumor size, laterality, advanced stage, LN positivity, and institutional volume. A total of 390 (16.6%) patients had LN-positive disease. Median LN density for these LN-positive patients was 0.38 (range 0.02-1) (Summary Figure). Estimated 5-year OS was significantly improved for those with LN density ≤0.38 vs. >0.38 (94% vs. 84.6%, P = 0.012). In this population, on multivariate analysis, age and LN density were significant predictors of OS.
It is difficult to compile large numbers of cases in rare diseases like WT, and fortunately a large administrative database such as the NCDB can serve as a great resource. However, administrative data come with inherent limitations such as missing data and inability to account for a variety of factors that may influence LN yield and/or OS (specimen designation, pathologist experience, surgeon experience/volume, institutional Children's Oncology Group (COG) association, etc.). In this specific disease, the American Joint Committee on Cancer staging (captured by the NCDB) is different than the COG WT staging system that is used clinically, and the NCDB does not capture oncologic outcomes beyond OS.
In a review of the NCDB, various factors associated with LN yield and observed LN density were identified to be significantly associated with OS in patients with LN-positive FHWT. This reinforces the need for adequate LN sampling at the time of WT surgery, to maximize surgical disease control. It was proposed that LN density as a metric may allow for improved risk-stratification, and possibly allow for therapeutic reduction in a sub-set of patients with low LN density.
在具有良好组织学（FH）的 Wilms 肿瘤（WT）的管理中，淋巴结（LN）取样或解剖的作用存在争议，特别是其作用方式以及对生存的影响。
本研究旨在分析影响 LN 取样模式的因素，以及在晚期 FHWT 患者中，LN 检出量和密度（阳性 LN 数/LN 检查数）对总生存率（OS）的影响。
利用国家癌症数据库（NCDB）查询 2004 年至 2013 年期间具有 FHWT 的患者。对接受手术切除的患者提取人口统计学、临床和 OS 数据。采用泊松回归分析影响 LN 检出量的因素。对有阳性 LN 的患者计算 LN 密度并进行进一步分析。
共有 2340 名患者符合标准，中位诊断年龄为 3 岁（范围 0-78 岁）。中位检查 LN 数为 3 个（范围 0-87 个）。LN 检出量受年龄、种族、保险、肿瘤大小、侧别、分期、LN 阳性和机构容量的影响。共有 390 名（16.6%）患者有 LN 阳性疾病。这些 LN 阳性患者的中位 LN 密度为 0.38（范围 0.02-1）（总结图）。LN 密度≤0.38 与＞0.38 的患者 5 年 OS 估计值有显著差异（94% vs. 84.6%，P=0.012）。在该人群中，多变量分析显示，年龄和 LN 密度是 OS 的显著预测因素。
在 WT 等罕见疾病中，很难汇集大量病例，幸运的是，像 NCDB 这样的大型管理数据库可以成为一个很好的资源。然而，管理数据存在固有局限性，例如数据缺失，以及无法考虑可能影响 LN 检出量和/或 OS 的各种因素（标本指定、病理学家经验、外科医生经验/数量、机构儿童肿瘤学组（COG）关联等）。在这种特定疾病中，美国癌症联合委员会（AJCC）分期（由 NCDB 捕获）与临床上使用的 COG WT 分期系统不同，并且 NCDB 不捕获除 OS 以外的肿瘤学结局。
在对 NCDB 的审查中，确定了与 LN 检出量和观察到的 LN 密度相关的各种因素，这些因素与 LN 阳性 FHWT 患者的 OS 显著相关。这再次强调了在 WT 手术时需要进行足够的 LN 取样，以最大限度地控制手术疾病。有人提出，LN 密度作为一种指标可能有助于改善风险分层，并可能使低 LN 密度亚组患者的治疗得到降低。
