Valuation of lymph node dissection in localized high-risk renal cell cancer using X-tile software.

Attempt to group the number of lymph nodes in a more ideal way to assess the value of lymph node dissection (LND) in the treatment of localized high-risk renal cell cancer (LH-RCC).

The Surveillance, Epidemiology, and End Result database (SEER) was used to analyze LH-RCC patients who undergoing radical nephrectomy (RN) from 2011 to 2015. The X-tile software was performed to calculate the optimal grouping cut-off points for the number of removed lymph nodes and positive lymph nodes. The Nomogram model was constructed by R language to visually present survival rates of patients.

Among 4917 cases of LH-RCC patients undergoing RN, there were 1835 patients treated with LND (37.32%) with the average survival time (AST) of 43.10 months (95% CI 41.91-44.29), which was superior than 40.52 months of patients who did not have LND (95% CI 39.26-41.78) (P < 0.01). The mortality risk of patients with ≥ 3 removed nodes was 0.75 times that of patients with 1-2 removed nodes (95% CI 0.62-0.99, P < 0.01). For overall survival (OS), the hazard ratio of ≥ 5 positive nodes, 1-4 positive nodes, and 0 positive node was 3.04, 2.37, and 1.00, respectively. The Nomogram model can evaluate the 1 year, 2 year, and 3 year survival rates of LH-RCC patients undergoing RN with the internal validation C-index of 0.73.

LH-RCC patients with ≥ 3 removed lymph nodes and fewer positive lymph nodes are expected to have better long-term survival. LND is not only helpful for tumor staging of LH-RCC, but also valuable for long-term survival.

International urology and nephrology. 2019 Oct 14 [Epub ahead of print]

Wei Zhuang, Jiabi Chen, Yining Li, Weihui Liu

Department of Urology, The Second Affiliated Hospital of Fujian Medical University, Zhongshan North Road, Licheng District, Quanzhou, 362000, Fujian, China., Department of Urology, The Second Affiliated Hospital of Fujian Medical University, Zhongshan North Road, Licheng District, Quanzhou, 362000, Fujian, China. .