Quantitative Metastatic Lymph Node Burden and Survival in Merkel Cell Carcinoma

Abstract Background Current lymph node (LN) staging for Merkel cell carcinoma (MCC) does not account for number of metastatic LNs, which is a primary driver of survival in multiple cancers. Objective To determine the impact of number of positive LNs on survival in MCC. Methods Patients with MCC undergoing surgery were identified from the NCDB and SEER. The association between LN number and survival was modeled with restricted cubic splines. A novel nodal classification system was derived using recursive partitioning analysis (RPA). Results Among 3670 patients, increasing metastatic LN number was associated with decreased survival (P Limitations Retrospective design Conclusions Number of metastatic LNs is the dominant nodal factor driving survival in patients with MCC.