Number of Positive Lymph Nodes Combined with the Logarithmic Ratio of Positive Lymph Nodes predicts Survival in Patients with Non-Metastatic Larynx Squamous Cell Carcinoma

Abstract

Background: Logarithmic ratio of positive lymph nodes (LODDS), number of positive lymph nodes (NPLN), and number of lymph nodes to positive lymph nodes (pLNR) are three lymph node classifications; however, their function in prognosis is unclear. Purpose: To establish and validate an optimal nomogram according to the comparison among the 7 th TNM stage of American Joint Committee on Cancer (AJCC) and the three lymph node classifications. Methods: A total of 881 patients from the Surveillance, Epidemiology and End Result (SEER database) with T1-4N1-3M0 in laryngeal squamous cell carcinoma from 2000 to 2018 were involved. The enrolled patients were allocated randomly into a training cohort and a validation cohort. Univariate cox regression analysis and multivariable cox regression analysis were applied to explore the predictors. The Akaike Information Criterion (AIC) and Harrell's concordance index (C-index) were to measure the predictive value and the accuracy of the prognostic models. Moreover, integrated discrimination improvement (IDI) and net reclassification index (NRI) were also used to assess the predictive abilities to models. According to the optimal model, nomograms were established and compared with 7 th TNM stage of AJCC via the decision curve analysis. Results: NPLN, LODDS, and pLNR were three predictors for the overall and cancer-specific survival in the larynx squamous cell carcinoma. According to the AIC, C-index, IDI, and NRI, the model of NPLN combined with LODDS was assumed as the optimal prognostic model. Moreover, the decision curve analysis suggested that the nomogram demonstrated a better predictive performance, compared with the 7 th AJCC TNM stage. Conclusion:The proposed nomograms we constructed for larynx squamous cell carcinoma has potential in the prediction of patients after surgery.

Impact of lymph node ratio and number of lymph node metastases on survival and recurrence in laryngeal squamous cell carcinoma

“…AJCC nodal staging of the larynx is mainly based on the anatomical location of the lymph nodes (single or multiple, site, and size), without considering the absolute number and ratio of positive lymph nodes 22 . The limitations of the current laryngeal TNM staging system are highlighted by the data reported in our case study, which agrees with those published in similar studies 18,21,23,25,26 . In particular, the comparison of our patients based on pTNM revealed that there were no significant differences in terms of DSS and DFS in patients with stages I–III disease and that the only significant differences were observed for stages IVA and IVB.…”

“…22 The limitations of the current laryngeal TNM staging system are highlighted by the data reported in our case study, which agrees with those published in similar studies. 18,21,23,25,26 In particular, the comparison of our patients based on pTNM revealed that there were no significant differences in terms of DSS and DFS in patients with stages I-III disease and that the only significant differences were observed for stages IVA and IVB.…”

“…Interesting findings on the impact of lymph node metastasis have been reported by Wang et al 26 who conducted a complex analysis of overall and cancer‐specific survival in patients with laryngeal cancer, considering three parameters: LNR, logarithmic ratio of positive lymph nodes (LODDS), and NPLN. The authors also developed improved prognostic models and demonstrated that NPLN combined with LODDS was the optimal prognostic choice.…”

“…Several earlier studies have attempted to identify specific cut‐offs for both LNR and NPLN to better estimate survival in head and neck cancer. A limited number of studies have conducted this analysis exclusively on patients with laryngeal cancer 18–21,25–28 . Currently, there is no consensus about the significant values for LNR and NPLN that could be used in clinical practice for oncological staging and prognosis.…”

“…A limited number of studies have conducted this analysis exclusively on patients with laryngeal cancer. [18][19][20][21][25][26][27][28] Currently, there is no consensus about the significant values for LNR and NPLN that could be used in clinical practice for 20 on 101 patients showed that the LNR cut-off value for a meaningful separation was 0.09. The presence of an LNR > 0.09 was the only significant independent prognostic factor for OS and DFS.…”