Significance of examined lymph-node count in accurate staging and long-term survival in patients undergoing radical
Cheng Chen1, Jie Shen1, Zhaoyu Xing1
1Department of Urology, The Third Affiliated Hospital of Soochow University, 185 Juqian Street, Changzhou, 213003, People's Republic of China.
Purpose:
The number of examined lymph node (ELN) is regarded as the critical quality index for cancer care. We scrutinize the relationship among ELN number, accurate staging, and long-term survival in prostate cancer (Pca).
Methods:
Population-based data on Pca patients in 2004-2015 from the US SEER database were investigated. The connection among ELN number and stage migration, overall survival (OS), and prostate cancer-specific survival (CSS) were evaluated by performing multivariable-adjusted logistic, Cox proportional hazards, and fine-gray competing-risk regression models, respectively. LOWESS smoother was used to fit the series of ELN number, odds ratios (OR), and hazard ratios (HR), while the Chow test was used to resolve the structural breakpoints. Subgroup and interaction analyses were performed in different risk populations.
Results:
Overall, 84,838 patients were analyzed. Serial improvements were seen in stage migration (OR, 1.072, P < 0.001), OS (HR, 0.991; P < 0.001), and CSS (HR, 0.983; P < 0.001) per additional ELN after adjusting for confounders. Subgroup analysis revealed that the ELN number gains the most staging and survival benefits in high-risk population (P for interaction < 0.001). Cut-point analyses suggested that an optimal number of 12 ELNs, which was verified by the cumulative incidence curve, had a strong capability to distinguish different probabilities of CSS.
Conclusions:
Higher quantities of ELNs are related to more-accurate nodal staging and long-term survival of Pca patients undergoing RP. We highlight that 12 ELNs are the optimal cut-point for the high-risk population to investigate the quality of LN detection and stratifying postoperative prognosis.
