Number Of Examined Nodes Research Articles

A Novel Criterion for Lymph Nodes Dissection in Distal Pancreatectomy for Ductal Adenocarcinoma: A Population Study of the US SEER Database

The aim of this study was to clarify the minimum number of examined lymph nodes (MNELNs) required to ensure the quality of lymph node detection and its impact on long-term survival in distal pancreatectomy for pancreatic ductal adenocarcinoma. Clinicopathological characteristics and survival data of patients with resectable pancreatic cancer who underwent distal pancreatectomy between 2004 and 2017 were collected from the Surveillance, Epidemiology, and End Results database. The associations between the number of examined lymph nodes (ELNs) and number of positive lymph nodes (PLNs), stage migration, and overall survival were investigated through adjusted multivariate models with locally weighted scatterplot smoothing smoothing fitting curves and estimation of the structural breakpoints. Kaplan-Meier survival analysis and X-tile software were used to identify the ideal cut-off value for ELNs. In total, 2610 consecutive patients who underwent distal pancreatectomy between 2004 and 2017 were included in this study. The optimal ELN count according to the associations between the number of ELNs and number of PLNs, odds ratio for stage migration, or hazard ratio for overall survival were 19, 17, and 19, respectively. Furthermore, the optimal division of ELN count for maximum overall survival was divided into three populations (ELN≤8, ELN 9-18, ELN≥19) based on X-tile software. A minimal count of 19 lymph nodes was demanded to guarantee the quality of lymph node examination in patients with distal pancreatectomy. Long-term survival could be delimited by MNELNs. A sufficient number of ELNs could improve the accuracy of cancer staging and reflect a better overall survival.

Novel Trocars and Suspension System Application in Gasless Transoral Endoscopic Thyroidectomy Vestibular Approach Oral Endoscopic Surgery.

In the current study, we reported our initial experience of gasless transoral endoscopic thyroidectomy vestibular approach (TOETVA) by novel trocars and a suspension system. Between February 2019 to September 2020, thyroid cancer patients with indicated central lymph node metastasis by imaging examination who had received gasless TOETVA by our designed trocars and suspension system in The First Affiliated Hospital of University of Science and Technology of China were reviewed. A total of 95 thyroid cancer patients that received gasless TOETVA were included in this analysis. Of note, 73 cases underwent one-sided lobectomy and the remaining 22 cases underwent total thyroidectomy. All thyroid cancer patients underwent central lymph node dissection (CND). The average total examined lymph nodes number was 8.55 ± 5.67 per individual. No serious complications occurred during or after the operation besides one patient who had a short-term recurrent laryngeal nerve (RLN) deficit and one patient who had delayed postoperative bleeding. In conclusion, the use of novel trocars and a suspension system can effectively improve the safety and efficacy of TOETVA.

Optimal Examined Lymph Node Count in Node-Negative Colon Cancer Should be Determined

Background: We aimed to investigate the association between optimal examined lymph node (ELNs) and overall survival to determine the optimal cutoff point. Methods: Cox models and locally weighted scatterplot smoothing were used to fit hazard ratios and explore an optimal cutoff point based on the Chow test. Results: Overall survival increased significantly with the corresponding increase in the number of ELNs after adjusting for covariates. In Chow's test, the optimal cutoff point for node-negative colon cancer was 15, which was validated in both cohorts after controlling for confounders (Surveillance, Epidemiology, and End Results database: hazard ratio: 0.701, p < 0.001; single-center: HR: 0.563; p = 0.031). Conclusions: We conservatively suggest that the optimal number of ELNs for prognostic stratification is 15 in node-negative colon cancer.

Exceeding 30 ELNs is strongly recommended for pT3-4N0 patients with gastric cancer: A multicenter study of survival, recurrence, and prediction model.

The argument concerning the exact minimum number of examined lymph nodes (ELNs) has continued for a long time among various regions, and no consensus has been reached for stratified pathological T stages for data to date. Data from 4607 pN0 patients with gastric cancer were analyzed. Kaplan‐Meier analysis showed the similar overall survival (OS) outcomes among the 3 groups (ELNs ≤ 15, 16 ≤ ELNs ≤ 29 and ELNs ≥ 30, P = .171). However, the ELNs ≥ 30 group had a better disease‐free survival (DFS) outcome compared with the others (all P < .05). An increased ELN group (ELNs ≥ 30) showed an improved OS only for pT3 patients (hazard ratio [HR] = 0.397, 95% confidence interval (CI): 0.182‐0.866, P = .020), while an improved DFS for pT3 patients (HR = 0.362, 95%CI: 0.152‐0.860, P = .021) and pT4 patients (HR = 0.484, 95%CI: 0.277‐0.844, P = .011) in the multivariate analysis. A well discriminated and calibrated nomogram was constructed to predict the probability of the OS and DFS, with the C‐index for OS and DFS prediction of 0.782 (95%CI: 0.735 to 0.829) and 0.738 (95%CI: 0.685 to 0.791), respectively. This study provides new and useful insights into the impact of ELN count on reducing stage migration and postoperative recurrence of pN0 patients with gastric cancer in 2000‐2017. In conclusion, a larger number of ELNs is suggested for surgeons to prolong the prognosis of pN0 gastric cancer, especially for pT3 patients.

A New Nomogram for Predicting Overall Survival and Assisting Postoperative Adjuvant Treatment Decision-Making in Stage II Oral Tongue Squamous Cell Carcinoma: A Surveillance, Epidemiology and End Results (SEER) Database Analysis

The survival benefit of postoperative adjuvant treatment (POAT) for stage II oral tongue squamous cell carcinoma (OTSCC) remains controversial. This large SEER-based study aims to establish a prognostic nomogram to visualize the overall survival of these patients and to aid in POAT decision making. The cut-off points of age at diagnosis and examined lymph node number (ELN) were determined using the population-based data from the SEER database. Univariate and multivariate Cox hazards regression models were utilized to identify prognostic factors that were integrated into the establishment of the prognostic nomogram. Patients with stage II OTSCC were then stratified into 3 cohorts based on this nomogram. The survival benefit of POAT was evaluated in these cohorts. Age at diagnosis (with cutoff points of 50 and 75 years) and ELN (with cutoff points of 0 and 22) was significantly associated with the survival outcomes in patients with stage II OTSCC. After the multivariate analysis, 4 factors, including age at diagnosis, sex, ELN, and differentiation grade, were identified as independent prognostic factors. Additionally, a prognostic nomogram with these factors was constructed to predict overall survival and to stratify these patients. Only patients in the high-risk cohort could significantly benefit from postoperative adjuvant treatment. This prognostic nomogram could accurately predict the overall survival of stage II OTSCC patients after curative surgery. Notably, this model could also assist the decision-making of postoperative adjuvant treatment for patients with stage II OTSCC.

Comprehensive analysis of prognostic value of lymph node staging classifications in patients with head and neck squamous cell carcinoma after cervical lymph node dissection

PurposeTo determine the optimal threshold of examined lymph node (ELN) number from cervical lymph node dissection for head and neck squamous cell carcinoma (HNSCC). Further to compare the prognostic value of multiple lymph node classification systems and to determine the most suitable scheme to predict survival. MethodsA total of 20991 HNSCC patients were included. Odds ratios (ORs) for negative-to-positive node stage migration and hazard ratios (HRs) for survival were fitted using the LOWESS smoother. Structural breakpoints were determined by the Chow test. The R square, C-index, likelihood ratio, and Akaike information criterion (AIC) were used to compare the prognostic abilities among AJCC N stage, number of positive lymph nodes (pN), positive lymph node ratio (LNR) and log odds of positive lymph nodes (LODDS) stages. ResultsA minimal threshold ELN number of fifteen had the discriminatory capacities for both stage migration and survival. LODDS stages had the highest R square value (0.208), C-index (0.736) and likelihood ratio (2467) and the smallest AIC value (65874). LODDS stages also showed prognostic value in estimating patients with AJCC N0 stage. A novel staging system was proposed and showed good prognostic performance when stratified by different primary sites. ConclusionFifteen lymph nodes should be examined for HNSCC patients. LODDS stage allows better prognostic stratification, especially in N0 stage. The proposed staging system may serve as precise evaluation tools to estimate postoperative prognoses.

Impact of the Extent of Lymph Node Dissection on Precise Staging and Survival in Clinical I-II Pure-Solid Lung Cancer Undergoing Lobectomy.

This study sought to determine the optimal number of examined lymph nodes (ELNs) and examined node stations (ENSs) in patients with radiologically pure-solid non-small cell lung cancer (NSCLC) who underwent lobectomy and ipsilateral lymphadenectomy by investigating the impact of ELNs and ENSs on accurate staging and long-term survival. Data from 6 institutions in China on resected clinical stage I-II (cI-II) NSCLCs presenting as pure-solid tumors were analyzed for the impact of ELNs and ENSs on nodal upstaging, stage migration, recurrence-free survival (RFS), and overall survival (OS). Correlations between different endpoints and ELNs or ENSs were fitted with a LOWESS smoother, and the structural break points were determined by Chow test. Both ELNs and ENSs were identified as independent prognostic factors for OS (ENS hazard ratio [HR], 0.690; 95% CI, 0.597-0.797; P<.001; ELN HR, 0.950; 95% CI, 0.917-0.983; P=.004) and RFS (ENS HR, 0.859; 95% CI, 0.793-0.931; P<.001; ELN HR, 0.960; 95% CI, 0.942-0.962; P<.001), which were also associated with postoperative nodal upstaging (ENS odds ratio [OR], 1.057; 95% CI, 1.002-1.187; P=.004; ELN OR, 1.186; 95% CI, 1.148-1.226; P<.001). A greater number of ELNs and ENSs correlated with a higher accuracy of nodal staging and a lower probability of stage migration. Cut-point analysis revealed an optimal cutoff of 18 LNs and 6 node stations for stage cI-II pure-solid NSCLCs, which were validated in our multi-institutional cohort. Extensive examination of LNs and node stations seemed crucial to predicting accurate staging and survival outcomes. A threshold of 18 LNs and 6 node stations might be considered for evaluating the quality of LN examination in patients with stage cI-II radiologically pure-solid NSCLCs.

Importance of Examined Lymph Node Number in Accurate Staging and Enhanced Survival in Resected Gastric Adenocarcinoma-The More, the Better? A Cohort Study of 8,696 Cases From the US and China, 2010-2016.

BackgroundWhile most guidelines advocate D2 lymphadenectomy for non-metastatic gastric adenocarcinoma (nmGaC), it is not always performed as standard of care outside East Asia. The recommended minimal examined lymph node (ELN) count in nmGaC to stage cancer accurately varies largely across guidelines, and the optimal count to satisfactorily stratify patient survival has yet to be determined. This large cohort study aimed at robustly defining the minimal and optimal thresholds of examined lymph node (ELN) number in non-metastatic gastric adenocarcinoma (nmGaC).MethodsData on nmGaC patients operated in 2010–2016 and surviving ≥3 months were retrieved from the US SEER-18 Program and a Chinese multi-institutional gastric cancer database (MIGC). The correlation of ELN count with stage migration and patient survival were quantified with the use of the multivariable-adjusted logistic and proportional hazards Cox models, respectively. The sequences of odds ratios (ORs) and hazard ratios (HRs) for each additional ELN were smoothed, and the structural breakpoints were determined.ResultsTogether 7,228 patients from the US and 1,468 from China were analyzed, encompassing 23,114 person-years of follow-up. The mean ELN count was 20 in the US and 30 in China. With more ELNs, both cohorts significantly showed proportional increases from lower to higher nodal stage (ORSEER = 1.03, 95%-CI = 1.03–1.04; ORMIGC = 1.02, 95%-CI = 1.02–1.03) and sequential enhancements in postoperative survival (HRSEER = 0.97, 95%-CI = 0.97–0.97; HRMIGC = 0.98, 95%-CI = 0.97–0.99). Correlations for both stage migration and survival were still significant in most subgroups by patient, cancer, and management factors. Breakpoint analyses revealed a minimum threshold ELN count of 17 and an optimum count of 33, which were validated in both cohorts with good efficacy to differentiate probabilities of both stage migration and survival.ConclusionIn resected nmGaC patients with anticipated survival ≥3 months, more ELNs are correlated with more accurate staging, which may partly explain the survival correlation. This observational investigation does not indicate causality. Our findings robustly conclude 17 ELNs as the minimum and propose 33 ELNs as the optimum thresholds, to assess the quality of lymph node examination and to stratify postsurgical survival.

The number of lymph nodes examined is associated with survival outcomes and nodal upstaging in patients with stage I small cell lung cancer

Objective(s)Lymph node status is vital for patients with small cell lung cancer (SCLC). We sought to evaluate the association between the number of lymph nodes examined (NLNE) and prognosis and nodal upstaging in stage I SCLC patients. MethodsWe queried the Surveillance, Epidemiology and End Results (SEER) database and our department for surgically treated patients with pathologic stage I SCLC to evaluate the correlation between NLNE and overall survival (OS). We further investigated the association between the NLNE and nodal upstaging in clinical stage I SCLC. ResultsA total of 878 patients with pathologic stage I SCLC were enrolled from the SEER database. Univariate and multivariate Cox regression analysis revealed that removing more than 6 lymph nodes was associated with significantly improved OS. We validated the prognostic impact from examining more than 6 nodes in pathologic stage I SCLC patients from our department. Logistic regression analysis found that removing more than 6 nodes increased the odds of nodal upstaging for clinical stage I SCLC. ConclusionsAdequate nodal examination leads to survival benefits and accurate nodal staging. Our analysis indicated that examining more than 6 lymph nodes could confer better OS and predict nodal upstaging for stage I SCLC patients.

Value of N1 Lymph Node Examination in the Prognosis of Patients With pT1-3N0M0 Non-Small Cell Lung Cancer.

ObjectiveThis study aimed to analyze the relationship between the number of examined lymph nodes (ELNs) at the N1 station and the postoperative clinicopathological features and prognosis of patients with pT1-3N0M0 non-small cell lung cancer (NSCLC).MethodsThe cut-off value of the number of ELNs at the N1 station was obtained using X-tile software analysis. Kaplan-Meier survival curve analysis and the Cox proportional hazard model were used to study the impact of the number of ELNs at the N1 station on the prognosis of postoperative patients with pT1-3N0M0 NSCLC.ResultsThe median survival time and 1-, 3- and 5-year survival rates of 0 ELNs at the N1 station were 28.0 months and 74.8%, 45.4%, and 21.2%, respectively. The median survival time and 1-, 3-, and 5-year survival rates of 1–4 ELNs at the N1 station were 45.0 months and 85.5%, 55.4%, and 39.1%, respectively. In the group with ≥ 5 ELNs at the N1 station, the median survival time and the 1-, 3- and 5-year survival rates were 59.0 months and 94.0%, 62.7%, and 48.2%, respectively. Both univariate and multivariate Cox regression analyses showed that the number of ELNs at the N1 station, T stage and operation type were independent factors affecting the prognosis of patients with pT1-3N0M0 NSCLC.ConclusionIncreasing the number of ELNs at the N1 station is positively correlated with the long-term survival rate of patients with T1-3N0M0 NSCLC. At least 5 LNs at the N1 station should be examined in pathological examination.

Stage migration resulting from inadequate number of examined lymph nodes impacts prognosis in stage II colon cancer after radical surgery.

We evaluated the impact of examined lymph node (ELN) number on the prognosis of stage II colon cancer after radical surgery and developed a novel prognostic scoring system by combining primary tumor extension (pT) and ELN number for reclassification of stage II colon cancer. Three cohorts of patients diagnosed with colon cancer between 2004 and 2010 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate analyses were performed to evaluate the relationship between factors and patients' survival including cause-specific survival (CSS) and overall survival (OS). Survival curves from subgroups were plotted by the Kaplan-Meier method and compared by the log-rank test. Cohort 1 and cohort 2 consisted of 13,960 and 5312 stage II colon cancer patients, respectively. Cohort 3 consisted of 4713 stage III patients. Factors including ELN, age, and pT were found to be associated with patients' survival in cohorts 1 and 2. Patients who were older or with smaller tumors were more likely to experience inadequate ELN. Patients with a higher score, as calculated by the novel scoring system, showed worse survival. Compared with stage III colon cancer patients, stage II patients with high scores had a comparable or even worse survival than stage IIIA and IIIB patients. Inadequate ELN leads to understaging in stage II colon cancer and predicts inferior prognosis. Our analyses show that the novel prognostic scoring system, consisting of combined pT and ELN, quantified stage migration effect and can be applied to the reclassification of stage II colon cancer.

Reassessment of the Optimal Number of Examined Lymph Nodes in Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma

The aim of this study was to reappraise the optimal number of examined lymph nodes (ELNs) in pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC). The well-established threshold of 15 ELNs in PD for PDAC is optimized for detecting 1 positive node (PLN) per the previous 7th edition of the American Joint Committee on Cancer (AJCC) staging manual. In the framework of the 8th edition, where at least 4 PLN are needed for an N2 diagnosis, this threshold may be inadequate for accurate staging. Patients who underwent upfront PD at 2 academic institutions between 2000 and 2016 were analyzed. The optimal ELN threshold was defined as the cut-point associated with a 95% probability of identifying at least 4 PLNs in N2 patients. The results were validated addressing the N-status distribution and stage migration. Overall, 1218 patients were included. The median number of ELN was 26 (IQR 17-37). ELN was independently associated with N2-status (OR 1.27, P < 0.001). The estimated optimal threshold of ELN was 28. This cut-point enabled improved detection of N2 patients and stage III disease (58% vs 37%, P = 0.001). The median survival was 28.6 months. There was an improved survival in N0/N1 patients when ELN exceeded 28, suggesting a stage migration effect (47 vs 29 months, adjusted HR 0.649, P < 0.001). In N2 patients, this threshold was not associated with survival on multivariable analysis. Examining at least 28 LN in PD for PDAC ensures optimal staging through improved detection of N2/stage III disease. This may have relevant implications for benchmarking processes and quality implementation.

Novel Approaches To Precisely Estimate Prognostic Significance Of Metastatic Lymph Nodes And Adequacy Of Lymphadenectomy On Esophageal Squamous Cell Carcinoma Patients: Beyond The Tip Of The Iceberg

Positive lymph node (PLN) has been proved to be an important prognostic factor for esophageal squamous cell carcinoma (ESCC), but the risk of occult metastatic disease in unexamined lymph nodes needs to be factored into decision making and the impact of the sufficiency of lymphadenectomy for these patients on prognosis has not yet been considered in the existing prognostic models. In this study, we aimed to precisely estimate the prognostic significance of PLN and adequacy of lymphadenectomy on ESCC patients by building a novel web-based application (app). 3674 ESCC patients underwent surgery without preoperative therapy from a multi-institutional cohort served as the training dataset and 2209 patients from the SEER database as the validation dataset. LOWESS smoother and Chow tests were used to identify the threshold for the examined lymph node (ELN) number during lymphadenectomy. Probability-based positive lymph node risk index (prPLN index) and lymph node adequately examined index (LNAE index) were created based on the Bayes’ theorem. Two Cox proportional hazards models integrating the novel indices and clinicopathological features were constructed and validated. The structural breakpoint of fifteen LNs was determined as the threshold ELN number. Multivariate Cox analysis showed the prPLN model combining the prPLN index with other parameters was significantly correlated with survival of ESCC patients. The “Adjusted LN Model,” based on the LNAE index and prPLN model was developed. In both training and validation sets, novel indices and models had better C-indices than AJCC N stage classifications and models (p < 0.001 for all). Finally, a web-based app was established to estimate the individual distribution of PLN, LNAE index and probability of postoperative prognoses. The web-based is novel, robust, and reliable which predicts survival rates and comprehensively reflects the influence of the precise PLN number and the adequacy of lymphadenectomy on prognosis for ESCC. From a clinical standpoint, this an effectively serve as a precise evaluation approach to estimate the prognosis for each individual patient.

Impact of Examined Lymph Node Count for Esophageal Squamous Cell Carcinoma in Patients who Underwent Right Transthoracic Esophagectomy.

The impact of the number of examined lymph nodes (ELNs) on stage correction and prognostication in patients with esophageal squamous cell carcinoma (ESCC) who underwent right transthoracic esophagectomy is still unclear. Patients with ESCC who underwent right transthoracic esophagectomy at Sun Yat-sen University Cancer Center between January 1997 and December 2013 were retrospectively enrolled. The Cox proportional hazards regression model was used to determine the effect of ELN count on overall survival. The impact of ELN count on stage correction was evaluated using the hypergeometric distribution and Bayes theorem and β-binomial distribution estimation, respectively. The threshold of ELNs was determined using the LOWESS smoother and piecewise linear regression. Among the 875 included patients, greater ELNs were associated with a higher rate of nodal metastasis. Significant association between staging bias and the number of ELNs is only observed through the Bayes method. The ELN count did not impact 90-day mortality but significantly impacted long-term survival (adjusted hazard ratio [aHR] 0.986), especially in those patients with node-negative disease (aHR 0.972). In patients with node-negative disease, cut-point analysis showed a threshold ELN count of 21. A greater number of ELNs is associated with more accurate node staging and better long-term survival in resected ESCC patients. We recommended harvesting at least 21 LNs to acquire accurate staging and long-term survival information for patients with declared node-negative disease using the right thoracic approach.

Evaluating the adequacy of nodal status in node-negative gallbladder cancer with T1b-T2 stages: use of nodal staging score

BackgroundThe study aimed at establishing a nodal staging score (NSS) to quantify the likelihood that pathologic node-negative gallbladder cancer (GBC) patients are indeed free of lymph node (LN) metastasis. MethodsClinicopathological data of 1374 GBC patients with T1b-T2 stages were collected from the Surveillance, Epidemiology and End Result database (design cohort [DC], n = 1289) and the First Affiliated Hospital of Sun Yat-sen University (validation cohort [VC], n = 85). NSS was derived from the count of examined LNs (ELNs) and T stage by using a beta-binomial model, and represented the probability that a node-negative patient is correctly staged. The prognostic value of NSS in node-negative GBC was evaluated by survival analysis. ResultsThe probability of missing a nodal disease in node-negative GBC patients with T1b-T2 stages (pT1bN0 and pT2N0) decreased as the number of ELNs increased. NSS increased as the number of ELNs increased. For pT1bN0 and pT2N0 patients, examination of 5 and 27 lymph nodes could ensure an NSS of 90.0%, respectively. Multivariate analysis revealed that NSS was an independent predictor for overall survival in pT1bN0 and pT2N0 GBC patients (DC, HR:0.53, 95%CI: 0.42–0.66, p < 0.001; VC, HR: 0.33, 95%CI: 0.14–0.76, p = 0.009). ConclusionNSS could evaluate the adequacy of nodal staging and predict the prognosis in pT1bN0 and pT2N0 GBC patients, and hence was helpful to guide their treatment strategies.

Impact of examined lymph node count on staging and long-term survival of patients with node-negative stage III gastric cancer: a retrospective study using a Chinese multi-institutional registry with Surveillance, Epidemiology, and End Results (SEER) data validation.

BackgroundAccumulating evidence has confirmed the potential prognostic value of examined lymph nodes (ELNs) in patients with gastric cancer (GC). However, there is currently no consensus on the threshold ELN number for predicting both stage migration and long-term survival, especially in patients with stage III GC. This study aimed to validate the need to increase the ELN count to improve its prognostic accuracy in node-negative patients with stage III GC after curative gastrectomy.MethodsThis retrospective, population-based study analyzed the clinical data of 84 patients with node-negative stage III GC from three high-volume institutions in China and 196 cases from the Surveillance, Epidemiology and End Results (SEER) program registry. The optimal number of ELNs was determined by receiver operating characteristic (ROC) curve analysis. Clinicopathological characteristics significantly related to survival were evaluated using the Kaplan-Meier method and Cox proportional hazards analysis. Stratified analyses were adopted to assess the prognostic predictive ability of the identified optimal number of ELNs in different populations. Survival differences among subgroups were analyzed to assess the impact of ELN count on stage migration according to overall survival (OS) among GC patients.ResultsThe optimal number of ELNs was >31 according to ROC analysis of patients with node-negative stage III GC who underwent gastrectomy. Multivariate analysis identified ELNs as an independent predictor of postoperative OS in patients with node-negative stage III GC in both the Chinese cohort [hazard ratio (HR) 0.235; P<0.001] and the SEER cohort (HR 0.421; P<0.010). Stratified analysis demonstrated that >31 ELNs was a prerequisite for accurate prognostic evaluation of patients with node-negative stage III GC, regardless of sex, tumor size, and other factors. Stage migration between pT4bN0M0 and pT4bN1M0 was detected in patients with >31 ELNs. A nomogram was created to predict OS among patients with node-negative stage III GC. These results were validated using data from the SEER cohort.ConclusionsThe number of ELNs was significantly associated with prognosis in patients with stage III GC after gastrectomy with systemic lymphadenectomy in both the Chinese and SEER cohorts. The results suggest that >31 ELNs are required for an accurate prognostic evaluation in patients with GC, especially those with node-negative stage III GC.

The assessment of the optimal number of examined lymph nodes and prognostic models based on lymph nodes for predicting survival outcome in patients with stage N3b gastric cancer.

The optimal number of examined lymph nodes (ELNs) and the prognostic value of different nodal staging systems remain unclear in the context of N3b gastric cancer. To evaluate the optimal number of ELNs and compare the predictive ability of the ELN number, LN ratio (LNR), and log odds of metastatic LNs (LODDS) for overall survival (OS) in patients with resected stage N3b gastric adenocarcinoma in an international database. A total of 868 patients diagnosed between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database (training cohort) and 144 patients diagnosed between 2011 and 2016 at the Liaoning Cancer Hospital (validation cohort) were identified. Cutoff values were established with X-tile. The 5-year OS rates were compared using Kaplan-Meier curves. Multivariate analysis was conducted with a Cox regression model. The Harrell's concordance index and Akaike's information criterion were used to compare the predictive accuracy of different nodal staging systems. The ELN number, LNR, and LODDS were independent prognostic factors for both the training and validation cohorts in the multivariate analysis. Patient with ≤26 ELNs, LNR of more than 0.9, and LODDS of more than 1.0 were associated with decrease OS. The LNR and LODDS had similar discriminatory ability for OS and performed better than the ELN number in the Eastern and Western populations. The optimal number of ELN may be 27 or more because LNs retrieved ≤26 was an independent risk factor for the prognosis. The prognostic prediction efficacy of LNR and LODDS was similar and better than that of ELN. Thus, LNR and LODDS could both serve as valid tools to predict OS for stage N3b patients.

Impact of examined lymph node count on prognosis in patients with lymph node-negative pancreatic body/tail ductal adenocarcinoma.

Because the overall prognosis remains dismal for patients with resected pancreatic cancer (PC), we aimed to explore the prognostic impact of examined lymph node (ELN) count on lymph node (LN)-negative pancreatic body/tail ductal adenocarcinoma. Patients' data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database (National Cancer Institute, USA) to investigate the relationship between ELN count and survival outcomes of LN-negative pancreatic body/tail ductal adenocarcinoma. A total of 700 patients were included, and the median number of ELNs was 11. The respective 1-, 3-, 5-year overall survival (OS) rates were 75.3%, 37.7%, 30.3%, and the 1-, 3-, 5-year cancer-specific survival (CSS) were 78.3%, 41.7%, 34.5%. The X-tile analysis showed that 14 was the most optimal cutoff for both OS and CSS. Kaplan-Meier survival analysis indicated that patients with ELNs >14 had better OS and CSS than ELNs ≤14. Multivariate Cox analysis showed ELNs ≤14 was an independent risk factor for both OS [hazard ratio (HR), 1.357; 95% confidence interval (CI), 1.080-1.704; P=0.009] and CSS (HR, 1.394; 95% CI, 1.092-1.778; P=0.008). ELN count is associated with the survival rate in patients with LN-negative pancreatic body/tail ductal adenocarcinoma. Accurate nodal staging for these patients requires more than 14 ELNs.

Prognostic Impact of the Number of Examined Lymph Nodes in Stage II Colorectal Adenocarcinoma: A Retrospective Study.

Background Evaluation of lymph node status is critical in colorectal carcinoma (CRC) treatment. However, as patients with node involvement may be incorrectly classified into earlier stages if the examined lymph node (ELN) number is too small and escape adjuvant therapy, especially for stage II CRC. The aims of this study were to assess the impact of the ELN on the survival of patients with stage II colorectal cancer and to determine the optimal number. Methods Data from the US Surveillance, Epidemiology, and End Results (SEER) database on stage II resected CRC (1988-2013) were extracted for mathematical modeling as ELN was available since 1988. Relationship between ELN count and stage migration and disease-specific survival was analyzed by using multivariable models. The series of the mean positive LNs, odds ratios (ORs), and hazard ratios (HRs) were fitted with a LOWESS (Locally Weighted Scatterplot Smoothing) smoother, and the structural break points were determined by the Chow test. An independent cohort of cases from 2014 was retrieved for validation in 5-year disease-specific survival (DSS). Results An increased ELN count was associated with a higher possibility of metastasis LN detection (OR 1.010, CI 1.009-1.011, p < 0.001) and better DSS in LN negative patients (OR 0.976, CI 0.975-0.977, p < 0.001). The cut-off point analysis showed a threshold ELN count of 21 nodes (HR 0.692, CI 0.667-0.719, p < 0.001) and was validated with significantly better DSS in the SEER 2009 cohort CRC (OR 0.657, CI 0.522-0.827, p < 0.001). The cut-off value of the ELN count in site-specific surgeries was analyzed as 20 nodes in the right hemicolectomy (HR 0.674, CI 0.638-0.713, p < 0.001), 19 nodes in left hemicolectomy (HR 0.691, CI 0.639-0.749, p < 0.001), and 20 nodes in rectal resection patients (HR 0.671, CI 0.604-0.746, p < 0.001), respectively. Conclusions A higher number of ELNs are associated with more-accurate node staging and better prognosis in stage II CRCs. We recommend that at least 21 lymph nodes be examined for accurate diagnosis of stage II colorectal cancer.

Impact of examined lymph node count for oesophageal squamous cell carcinoma in patients who underwent left transthoracic oesophagectomy

BackgroundThe impact of the number of examined lymph nodes (ELNs) on stage correction and prognostication in patients with oesophageal squamous cell carcinoma (ESCC) who underwent left transthoracic oesophagectomy is still unclear. MethodsPatients with ESCC who underwent left transthoracic oesophagectomy at Sun Yat-sen University Cancer Center between January 1997 and December 2013 were retrospectively enrolled. The Cox proportional hazards regression model was used to determine the effect of ELN count on overall survival (OS). The association between ELN count and nodal status was investigated through scatter plot and binary logistic regression analyses. The impact of ELN count on stage correction was evaluated using the hypergeometric distribution and Bayes theorem. The threshold of ELNs was determined using the LOWESS smoother and piecewise linear regression. ResultsAmong the 1826 included patients, greater ELNs were associated with a higher rate of nodal metastasis (adjusted OR = 1.018). When the ELN count increased, the omission rate of positive lymph nodes (LNs) decreased. The ELN count did not impact 90-day mortality but significantly impacted long-term survival (adjusted HR = 0.983), especially in those with node-negative disease (adjust HR = 0.972). In patients with node-negative disease, cut point analysis showed a threshold ELN count of 18. ConclusionsA greater number of ELNs is associated with more accurate node staging and better long-term survival in resected ESCC patients. We recommended harvesting at least 18 LNs to acquire accurate staging and long-term survival information for patients with declared node-negative disease in the left thoracic approach.