PM1060: Characteristics and Clinical Impact of Mesenteric Lymph Nodes in Neuroblastoma

Background: Common sites of metastasis in neuroblastoma (NB) include bone marrow, bone, liver, and lymph nodes (LNs). Often retroperitoneal and/or para-aortic LNs are involved depending on the tumor site. Rarely, mesenteric LNs are identified, despite absence of a defined drainage route from the tumor. We aimed to understand the characteristics and clinical impact of mesenteric LN involvement in NB patients.

Methods: We queried the electronic health record for all patients accrued to a NB-specific institutional database between 1/1/2011 and 9/13/2021. Patients who did not have abdominopelvic NB, did not undergo surgery or had insufficient data with regards to operation or LN excision were excluded. Survival data were compared between groups with and without involved mesenteric LNs.

Results: Our cohort included 662 patients, of which 49 (7.4%) had mesenteric LNs excised. Descriptive data is displayed in Table 1. Of the 49 patients with excised LNs, 32 (65.3%) contained NB and 17 (34.7%) were benign. All patients without excised LNs (N=613) were assumed to be negative for this analysis. In the overall cohort and high-risk patients, positive mesenteric LNs did not correlate with survival (p=0.099 and p=0.54, respectively). However, for low and intermediate-risk patients (N=102), positive mesenteric LNs were associated with a significantly decreased 5-year overall survival (48.6% vs. 93.3%, p< 0.0001) (Figure 1).

Conclusion: For patients with low and intermediate-risk abdominopelvic neuroblastoma, positive mesenteric LNs appear to negatively correlate with survival. Prospective evaluation of mesenteric nodes in these patients could further elucidate this finding.