Lymph Node Ratio Rather Than Positive Lymph Node Counts Has Better Prognostic Value in Patients With Testicular Germ Cell Tumors

Abstract

Background: Testicular cancer represents the most common malignancy in young adult men. In the current study, we sought to analyze and compare the prognostic value of lymph node ratio (LNR) as well as positive lymph node counts (LNC) to understand its clinical significance in testicular germ cell tumors. Methods: We employed eligibility criteria to recruit a total of 931 patients, with testicular cancer, from 2010 to 2015 from The Surveillance, Epidemiology, and End Results (SEER) database. We then used the X-Tile program to calculate LNR and LNC cutoff values and discriminate survival. We then calculated the overall and cancer specific survival rates and analyzed the association between LNR/LNC and clinical pathological characteristics using the χ2 test. Finally, we assessed the relationships between clinical pathological factors and patient survival using univariate Cox proportional hazard analysis. Results: Univariate analysis revealed a significant association between prognosis with age (HR, 5.169; 95% CI, 1.758-15.200; P = 0.003), AJCC stage (III vs I: HR, 9.298; 95% CI, 2.691-32.131; P < 0.001), M stage (HR, 7.897; 95% CI, 3.417-18.251; P < 0.001) and LNR (HR, 3.009; 95% CI, 1.275-7.098; P = 0.012). On the other hand, LNC (HR, 1.743; 95% CI, 0.687-4.420; P = 0.242) was not significantly associated with prognosis. Analysis of the association between LNR/LNC and clinical pathological characteristics showed that high LNR patients tended to have significantly larger tumor sizes (χ2 = 7.877, P = 0.005), as well as advanced T (χ2 = 13.195, P = 0.004), N ( χ2 = 86.775, P < 0.001), M (χ2 = 19.948, P < 0.001) and 7th AJCC (χ2 = 103.074, P < 0.001) stages. In addition, high LNC patients were significantly associated with T (χ2 = 8.799, P = 0.032), N (χ2 = 74.390, P < 0.001) and 7th AJCC (χ2 = 111.759, P < 0.001) stages. Conclusion: LNR was a better predictor for long-term prognosis and was closely associated with clinical pathological characteristics than LNC in patients with testicular germ cell tumors.