Metastatic lymph node ratio versus number of metastatic lymph nodes as a prognostic factor in gastric cancer

Positive lymph node ratio as a prognostic factor for gastric cancer patients: Is it going to supersede positive lymph node number in guidelines?

Gastric malignancies constitute the sixth most common cancer with regards to incidence and have the fifth most mortality rates. Extended lymph-node dissection is the surgical modality of choice while treating advanced stage gastric cancer. It is yet a topic of debate, whether or not the amount of positive lymph nodes after a pathological examination following the surgical intervention is of prognostic value. In this study, it is aimed to evaluate the prognostic significance of positive lymph nodes following the surgery. A total of 193 patients who underwent curative gastrectomy between January 2011 and December 2015 have been considered for a retrospective data collection. The cases with R1-R2 resections, palliative or emergent surgeries are excluded. Metastatic to total number of lymph nodes, corresponded a ratio which was analyzed in this survey and practiced as a predictive parameter of disease outcome. This survey includes 138 male (71.5%) and 55 female (28.5%) patients treated between 2011 and 2015 in our clinic. The survey follow-up duration of the cases range between 0, 2, and 72 months, corresponding an average of 23.24 ± 16.99 months. We calculated cutoff value of 0.09 with, sensitivity is 76.32% for positive to total number of lymph nodes ratio, whereas specivity applies for 64.10%, positive predictive value for 58% and negative predictive value for 80.6%. Positive lymph node ratio has a prognostic value in terms of predicting the prognosis of the patients with gastric adenocarcinoma following a curative gastrectomy. This might in long term contribute to the prognostic analysis of patients if integrated in the current staging system.

Prognostic significance of the metastatic lymph node ratio compared to the TNM classification in stage III gastric cancer

Background

We aimed to evaluate a comparative analysis of the prognostic value of the metastatic lymph node ratio (LNR) and pN (TNM) in stage III gastric cancer.

Patients and Methods

A total of 159 stage III gastric cancer patients with curative gastrectomy were retrospectively analyzed. Cutoff values for LNR were designated according to 25%, 50% and 75% percentiles, 0.07, 0.20 and 0.44 respectively. The LNR was divided into four groups as 0 > LNR1 ≤ 0.07; 0.07 > LNR2 ≤0.20; 0.20 > LNR3 ≤0.44; 0.44 > LNR4 ≤1.

Results

The mean age of the patients was 61.1 ± 11.3 years. Male predominance was apparent (73.6%). The 1-year overall survival and recurrence rates were 73.6% and 33.6%, respectively. The univariate cox regression analysis demonstrated age and LNR were the main variables that affected overall survival (OS) (p < 0.05). Harvested lymph nodes less than 16 did not affect OS (p = 0.255). The results of the multivariate cox regression analysis revealed that only LNR was an independent prognostic factor (P < 0.001), while pN was not (p > 0.05). Similar results, as with overall survival, could not be revealed clearly for disease free survival (DFS).

Conclusions

LNR was an independent significant prognostic factor and superior to pN staging in predicting OS but not for DFS in stage III gastric cancer patients. The high LNR levels in our research were found to be associated with poor survival rates. The percentile system we used to determine cutoff values may be considered as a reliable method. Similarly, LNR also provides a reliable prognostic parameter in future staging systems to help guide treatment algorithm plans.

Pathologic Lymph Node Staging of Gastric Cancer

OBJECTIVES

The TNM classification is the main tool for lymph node (LN) staging in gastric cancer (GC). However, alternative LN staging systems have been proposed, and the role of features other than the number of metastatic LNs is being investigated. Our aim is to discuss the main challenges of LN assessment in GC.

METHODS

Comprehensive review of the literature on alternative LN staging systems, examined LNs, sentinel LN (SLN) biopsy, LN micrometastases (LNMIs), extracapsular extension (ECE), and tumor deposits (TDs) in GC.

RESULTS

Many controversies exist regarding LN assessment in GC. The TNM classification shows excellent prognostic performance, but alternative prognostic methods such as the LN ratio or log odds of positive LNs have demonstrated to be better than the TNM system in terms of prognostic accuracy. The value of SLN biopsy and LNMIs in GC is still unclear, and several challenges concerning their clinical impact and pathologic analysis must be overcome before their introduction in clinical practice. Most authors have identified ECE and TDs as independent prognostic factors for survival in GC.

CONCLUSIONS

Further studies should be performed to evaluate the impact of these features on the TNM classification and patient outcomes, as well as to standardize alternative LN staging systems.

Which Lymph Node Staging System Better Predicts Prognosis in Patients With Gastric Carcinoma? A Comparative Study Between 3 Different Lymph Node Classifications for Resected Gastric Cancer in a Western Tertiary Center

INTRODUCTION

Gastric cancer (GC) is an aggressive disease with high mortality rates. Lymph node (LN) staging of GC is a major source of controversy. The aim of this study is to compare the prognostic value of 3 different LN classifications for patients with resected GC: the eighth TNM staging system, lymph node ratio (LNR, ratio between positive and total LN) and a new anatomic-based classification (Choi classification).

MATERIALS AND METHODS

A retrospective study of all cases of GC resected in a tertiary hospital in Spain (n=377). Clinical data were collected; histologic slides were reviewed; and univariate and multivariate analyses of disease-free survival (DFS) and overall survival (OS) were performed.

RESULTS

In all, 315 patients fulfilled inclusion criteria. Univariate analysis showed that all classifications were significantly associated with tumor death and progression (P<0.001). All staging systems were independent prognostic factors for DFS. Area under the curve ratios for Choi, N stage, and LNR classifications were 0.738, 0.730, and 0.735, respectively. TNM and LNR classifications were independent prognosticators for OS, while Choi classification was an independent factor only in patients with ≥16 LN resected. Area under the curve ratios for Choi, N stage, and LNR classifications were 0.707, 0.728, and 0.732, respectively. Kaplan-Meier curves depending on LNR classification showed the best patient stratification for both OS and DFS.

CONCLUSIONS

The 3-staging systems had similar prognostic performance, but LNR-based classification stratified patients better. Further studies are needed to evaluate the impact of the number of LN examined, cutoff values, and anatomic extent of LN disease in GC.

Critical number of lymph node involvement in esophageal and gastric cancer and its impact on long-term survival-A single-center 8-year study

BACKGROUND

Nodal disease in esophageal and gastric cancer is associated with poor survival.

OBJECTIVES

To determine the critical level of lymph node involvement where survival becomes significantly compromised.

METHODS

Survival analyses using multivariable Cox regression and receiver operator characteristics (ROC) were undertaken to determine what number of positive lymph nodes were most sensitive and specific in predicting survival.

RESULTS

A total of 317 patients underwent esophagectomy (n = 190, 59.9%) and gastrectomy (n = 127, 40.1%) for adenocarcinoma. At multivariable analyses, four nodes positivity (irrespective of T-category) was associated with nearly a fivefold increased risk of mortality when compared to node-negative patients (hazard ratio [HR], 4.9; interquartile range 2.0-11.5; P < .001). A positive ratio of up to 50.0% was not associated with worse survival than having four nodes positive (HR, 4.6; 95% confidence interval, 2.6-8.1; P < .001). ROC analysis demonstrated four lymph nodes positive to have a sensitivity of 80.5%, a specificity of 60.1%, and an accuracy of 77.8 (P < .001).

CONCLUSION

The absolute number of nodes positive for cancer is more important than the proportion of positive nodes in predicting survival in esophageal/gastric cancer. Four positive lymph nodes are associated with a fivefold increase in mortality. Beyond this, increasing numbers of positive lymph nodes make no appreciable difference to survival.

Association of Lymph Node Density With Survival of Patients With Papillary Thyroid Cancer

Importance

Lymph node metastases are common in papillary thyroid cancer (PTC), yet the impact of nodal metastases on survival remains unclear. Lymph node density (LND) is the ratio between the number of positive lymph nodes excised and the total number of excised lymph nodes. Lymph node density has been suggested as a prognostic factor in many types of cancer.

Objective

To evaluate the prognostic role of LND in PTC.

Design, Setting, and Participants

This cohort study reviewed medical records of patients with PTC who were treated at the University of Texas MD Anderson Cancer Center between January 1, 2000, and December 31, 2015. Survival and recurrence outcomes were calculated by using the Kaplan-Meier method. Significant variables on univariate analysis were subjected to a Cox proportional hazards regression multivariate model.

Main Outcomes and Measures

Primary study outcome was disease-specific survival (DSS); other measurements included overall survival (OS).

Results

The study cohort included data for 2542 patients (1801 [71%] male; median age, 48 years [range, 18-97 years]) with a median follow-up of 55 months (range, 4-192 months). The 10-year disease-specific survival rate was 98% for patients with LND of 0.19 or less, compared with 90% for those with LND greater than 0.19 (effect size, 8%; 95% CI, 4%-15%). The 10-year overall survival was 87% for patients with LND of 0.19 or less, compared with 79% for patients with LND greater than 0.19 (effect size, 8%; 95% CI, 3%-15%). Multivariable analysis revealed that LND greater than 0.19 was independently associated with an adverse DSS (hazard ratio [HR], 4.11; 95% CI, 2.11-8.97) and OS (HR, 1.96; 95% CI, 1.24-4.11). Subgroup analysis of patients with 18 or more lymph nodes analyzed revealed that LND greater than 0.19 remained a significant marker for DSS (HR, 2.94; 95% CI, 1.36-9.81) and OS (HR, 2.26; 95% CI, 1.12-5.34). Incorporating LND into the current American Joint Committee on Cancer staging system successfully stratified risk groups compared with the traditional TNM staging system.

Conclusions and Relevance

This single-institute study demonstrates the reproducibility of LND as a predictor of outcomes in PTC. Lymph node density can potentially assist in identifying patients with poorer survival who may benefit from more aggressive adjuvant therapy.

Definition of Prognosis Based on Lymph Node Metastasis and Elevation of Serum C-Reactive Protein for Patients with Gastric Carcinoma Treated with Curative Resection

PURPOSE

The aim of this study was to develop prognostic criteria based on the combination of nodal metastasis and preoperative elevation of serum C-reactive protein (CRP) for patients with gastric carcinoma that have been treated with curative resection.

METHODS

Three hundred and twenty patients with gastric carcinoma who had been treated with curative resection were enrolled. One point was provided for each incidence of nodal metastasis and preoperative elevation of serum CRP and we examined whether this cumulative score system could provide a strict stratification of survival.

RESULTS

Significant differences regarding survival were observed both between patients with scores of 0 and 1 (P < 0.0001) and between patients with scores of 1 and 2 (P < 0.0001). Multivariate analysis showed that the cumulative score (P = 0.0003) and the depth of the tumor (P = 0.016) were independent prognostic indicators.

CONCLUSIONS

Criteria for the prediction of prognosis in gastric carcinoma treated with curative resection based on tumor-related and host-related factors could provide a strict stratification. J. Med. Invest. 65:191-194, August, 2018.

Metastatic lymph node ratio and Lauren classification are independent prognostic markers for survival rates of patients with gastric cancer

The long-term prognosis for patients with gastric cancer (GC) following radical resection remains poor. It is important to identify prognostic markers to predict survival. In the present retrospective study, the association between the metastatic lymph node ratio (rN) and the Lauren classification on predicting overall survival (OS) was investigated. Furthermore, a subgroup analysis was performed on the Lauren classification, using rN score as an independent prognostic marker. In total, 261 pathologically confirmed patients with GC were retrospectively reviewed. Kaplan-Meier curves and Cox's proportional hazards modeling were applied to analyze the OS of patients, and were utilized in the subgroup analysis. Receiver operating characteristic (ROC) curves were used to compare the accuracy of prognosis between the rN score and lymph node staging (N stage). The χ² test was used to analyze the association between the rN score and Lauren classification. Univariate survival and multivariate analysis demonstrated that the rN score and Lauren classification were significant prognostic markers for patients with GC. The ROC analysis confirmed that the rN score was more effective than N staging for OS prediction. Subgroup analysis indicated that rN was more accurate at predicting OS time in patients with diffuse type GC. The rN score and the Lauren classification were independent prognostic factors for the OS of patients with GC following radical resection, and the rN score was more accurate than the N stage for predicting the prognosis. Overall, the rN may be suitable as an independent predictor for OS in patients with diffuse type GC.

Nomogram and recursive partitioning analysis to predict overall survival in patients with stage IIB-III thoracic esophageal squamous cell carcinoma after esophagectomy

We have developed statistical models for predicting survival in patients with stage IIB-III thoracic esophageal squamous cell carcinoma (ESCC) and assessing the efficacy of adjuvant treatment. From a retrospective review of 3,636 patients, we created a database of 1,004 patients with stage IIB-III thoracic ESCC who underwent esophagectomy with or without postoperative radiation. Using a multivariate Cox regression model, we assessed the prognostic impact of clinical and histological factors on overall survival (OS). Logistic analysis was performed to identify factors to include in a recursive partitioning analysis (RPA) to predict 5-year OS. The nomogram was evaluated internally based on the concordance index (C-index) and a calibration plot. The median survival time in the training dataset was 30.9 months, and the 5-year survival rate was 33.9%. T stage, differentiated grade, adjuvant treatment, tumor location, lymph node metastatic ratio (LNMR), and the presence of vascular carcinomatous thrombi were statistically significant predictors of 5-year OS. The C-index of the nomogram was 0.70 (95% CI 0.67-0.73). RPA resulted in a three-class stratification: class 1, LNMR ≤ 0.15 with adjuvant treatment; class 2, LNMR ≤ 0.15 without adjuvant treatment and LNMR > 0.15 with adjuvant treatment; and class 3, LNMR > 0.15 without adjuvant treatment. The three classes were statistically significant for OS (P < 0.001). Thus, the nomogram and RPA models predicted the prognosis of stage IIB-III ESCC patients and could be used in decision-making and clinical trials.

Superiority of lymph node ratio-based staging system for prognostic prediction in 2575 patients with gastric cancer: validation analysis in a large single center

This study aimed to evaluate the prognostic significance of node ratio (Nr), the ratio of metastatic to retrieved lymph nodes, and to investigate whether a modified staging system based on Nr can improve prognostic ability for gastric cancer patients following gastrectomy. A total of 2572 patients were randomly divided into training set and validation set, and the cutoff points for Nr were produced using X-tile. The relationships between Nr and other clinicopathologic factors were analyzed, while survival prognostic discriminatory ability and accuracy were compared among different staging systems by AIC and C-index in R program. Patients were categorized into four groups as follows: Nr0, Nr1: 0.00–0.15, Nr2: 0.15–0.40 and Nr3: > 0.40. Nr was significantly associated with clinicopathologic factors including macroscopic type, tumor differentiation, lymphovascular invasion, perineural invasion, tumor size, T stage, N stage and TNM stage. Besides, for all patients, Nr and TNrM staging system showed a smaller AIC and a larger C-index than that of N and TNM staging system, respectively. Moreover, in subgroup analysis for patients with retrieved lymph nodes < 15, Nr was demonstrated to have a smaller AIC and a larger C-index than N staging system. Furthermore, in validation analysis, Nr, categorized by our cutoff points, showed a larger C-index and a smaller AIC value than those produced in previous studies. Nr could be considered as a reliable prognostic factor, even in patients with insufficient (< 15) retrieved lymph nodes, and TNrM staging system may improve the prognostic discriminatory ability and accuracy for gastric cancer patients undergoing radical gastrectomy.

Alternative staging of regional lymph nodes in gastric cancer

The TNM pN stage based on the number of metastatic lymph nodes is an independent prognostic factor in gastric cancer. Many studies have highlighted the phenomenon of stage migration and problems in comparing groups of patients with different numbers of total lymph nodes harvested within TNM staging. The current version of UICC/AJCC and JGCA TNM classifications postulates a minimal number of 16 lymph nodes as the base for N stage determination. Alternative systems such as lymph node ratio (LNR), positive to negative lymph node ratio (PNLNR), and LOGODDS (or LODDS), were implemented to increase the quality of LN assessment. These methods have reached the background in the literature, but to date no standard approach according to the cut-offs for the stages has been implemented. LOGODDS is the method that most reflects the number of harvested lymph nodes. The rationale for alternative staging methods, their correlations, and limitations are presented.

Lymph node ratio as a novel and simple prognostic factor in advanced gastric cancer

TNM staging is no doubt the most critical prognostic factors, representing tumor (T)/lymph node metastasis (N)/distant metastasis (M) in gastric cancer. Lymph node ratio-based N system (Nr) has been repeatedly reported to be of prognostic relevance in advanced gastric cancer independent of stage in the multivariate analysis world-wide, and proposed as more sophisticated than N with regard to predicting accurate prognosis. As a result, proposed TNrM system may predict survival more accurately than the present TNM staging system for patients undergoing limited lymph node analysis. It could adjust stage migration when the lymph node number was used as staging factor. Although correlation of the number of metastatic lymph nodes and lymph node ratio is obvious, biological characteristics other than that could also have been reflected on. It may indicate how successful the operation of lymph node dissection was, or it may be revealing the potential of the patient's lymph node immune-reaction. Recently, high lymph node ratio is closely associated with EGFR expression in advanced gastric cancer. When efficiency of applying lymph node ratio as a biomarker is verified and confirmed in an expansive research, and when cancer causing molecules are identified, as well as the competence as a treatment target is studied, the new biomarker, namely, lymph node ratio, could find itself in a limelight in gastric cancer treatment in the future.

The Prognostic Importance of the Number of Metastatic Lymph Nodes for Patients Undergoing Curative Resection Followed by Adjuvant Chemoradiotherapy for Extrahepatic Bile Duct Cancer

BACKGROUND

Current nodal staging system for extrahepatic bile duct (EHBD) cancer is controversial. The number of metastatic lymph nodes (mLN) and lymph node ratio (LNR) has been studied for the assessment of the nodal status in many other gastrointestinal cancers, but there are few studies on assessing the prognostic impact of these parameters in EHBD cancer.

METHODS

We retrospectively reviewed 239 consecutive patients who underwent curative resection followed by adjuvant chemoradiotherapy for adenocarcinoma of EHBD from 1995 to 2009 in our institution. The prognostic value of the number of mLN and LNR was evaluated by adjusting for other known factors. Optimal cutoff points were determined using maximally selected chi-square test.

RESULTS

Lymph node metastasis was found in 77 (32 %) patients. Univariate analysis for overall survival (OS) revealed both the number of mLN (0 vs. 1-3 vs. ≥4; p < 0.001) and LNR (<0.2 vs. ≥0.2; p < 0.001) as significant prognosticators. Multivariate analysis demonstrated that the number of mLN was an independent prognostic factor, whereas LNR was not. The estimated 5-year OS was 48.7 % for patients with negative nodes, 33.4 % for patients with 1-3 mLN, and 9.1 % for patients with 4 or more mLN (p < 0.001).

CONCLUSIONS

The number of mLN is a powerful parameter to predict survival in the EHBD cancer, which is more reliable than LNR. As for many other gastrointestinal cancers, further classification of node positive patients based on the number of mLN seems to be useful and may provide precise information.

Ratio and log odds of positive lymph nodes in breast cancer patients with mastectomy

PURPOSE

This study aimed to investigate the predictive role of lymph nodes (LNs) and assess the prognostic significance of the ratio of positive LNs (LNR) and log odds of positive LNs (LODDS) in breast cancer patients who have undergone a mastectomy.

PATIENTS AND METHODS

All of the breast cancer patients in the Taiwan Cancer Database during 2002-2006 were considered. We excluded patients who had inflammatory breast cancer, stage 0 and IV disease, breast conservative surgery or survival <1 month. The primary end point was overall survival (OS). A Cox hazards model was constructed and compared via Nagelkerke R(2) (R(2)N) and receiver operating characteristics (ROC).

RESULTS

A total of 11,349 (6042 node-negative, 5307 node-positive) patients were enrolled, and 10.5% patients had a limited number of LNs harvested. In a multivariate Cox model, LNR and LODDS demonstrated prognostic significance (<0.001). For node-positive patients, a model with LNR showed the best fit (P < 0.001; R(2)N = 18.2%) when sufficient LNs were examined. However, a model with LODDS showed the best fit in patients with a limited number of LNs harvested (P < 0.001; R(2)N = 21.1%), even in node-negative patients (P = 0.004; R(2)N = 13.5%). The area under the ROC curve (AUC) was highest for LODDS (AUC: 0.761), followed by LNR (AUC: 0.757). A limited LN harvest induced an AUC value for an approximate 3.6% loss (LNR) or 3.1% loss (LODDS).

CONCLUSION

The prognostic superiority of LNR is confounded by a limited LN harvest, thus making LODDS the most powerful and unified prognostic classifier in breast cancer patients who have had a mastectomy.

Correlation between metastatic lymph node ratio and prognosis in patients with extrahepatic cholangiocarcinoma

AIM: To investigate the prognostic value of metastatic lymph node ratio (MLNR) in extrahepatic cholangiocarcinoma (ECC) patients undergoing radical resection.

METHODS: Seventy-eight patients with ECC were enrolled. Associations between various clinicopathologic factors and prognosis were investigated by Kaplan-Meier analyses. The Cox proportional-hazards model was used for multivariate survival analysis.

RESULTS: The overall three- and five-year survival rates were 47.26% and 23.99%, respectively. MLNR of 0, 0-0.2, 0.2-0.5, and > 0.5 corresponded to five-year survival rates of 28.59%, 21.60%, 18.84%, and 10.03%, respectively. Univariate analysis showed that degree of tumor differentiation, lymph node metastasis, MLNR, tumor-node-metastasis (TNM) stage, and margin status were closely associated with postoperative survival in ECC patients (P < 0.05). Multivariate analysis showed that MLNR and TNM stage were independent prognostic factors after pancreaticoduodenectomy (HR = 2.13, 95%CI: 1.45-3.11; P < 0.01; and HR = 1.97, 95%CI: 1.17-3.31; P = 0.01, respectively). The median survival time for MLNR > 0.5, 0.2-0.5, 0-0.2, and 0 was 15 mo, 24 mo, 23 mo, and 35.5 mo, respectively. There were statistical differences in survival time between patients with different MLNR (χ² = 15.38; P < 0.01).

CONCLUSION: MLNR is an independent prognostic factor for ECC patients after radical resection and is useful for predicting postoperative survival.

Prognostic significance of metastatic lymph node number, ratio and station in gastric neuroendocrine carcinoma

The objective of this study was to analyze the prognostic significance of metastatic lymph node status in gastric neuroendocrine carcinoma (GNEC) patients following radical gastrectomy. A consecutive series of 73 patients who underwent gastrectomy between 1999 and 2011 for GNEC was retrospectively reviewed. Indexes of lymph node involvement (the pN classification, metastatic lymph node number [MLNn], ratio [MLNr], and station [MLNs]) and other clinicopathological data were analyzed. Fifty-four patients met the inclusion criteria and were enrolled in the study. Among them, 44 patients (81 %) were found to have lymph node metastases. The median survival time of the entire cohort was 63.2 (range, 14-153) months with 3- and 5-year survival rates of 88.9 and 47.9 %, respectively. The median total number of lymph nodes, MLNn, and MLNr were 19 (range, 10-56), 5 (range, 1-21), and 25 % (6-100 %), respectively. Cox regression analysis revealed pN classification = 1, MLNn >2, MLNr >0.1, and MLNs = 2, and distant metastases influenced prognosis independently (P = 0.0266, 0.0091, 0.0031, 0.0119, and 0.0021, respectively). In addition to the pN classification, indexes of metastatic lymph node involvement, including MLNn, MLNr, and MLNs, were all significant predictors of survival in GNEC patients. Distant metastasis was also a significant prognostic factor. These indexes proved to be accurate and important supplements to survival factors, which may improve risk classification of GNEC patients.

Recursive partitioning analysis of lymph node ratio in breast cancer patients

Lymph node ratio (LNR) is a powerful prognostic factor for breast cancer. We conducted a recursive partitioning analysis (RPA) of the LNR to identify the prognostic risk groups in breast cancer patients. Records of newly diagnosed breast cancer patients between 2002 and 2006 were searched in the Taiwan Cancer Database. The end of follow-up was December 31, 2009. We excluded patients with distant metastases, inflammatory breast cancer, survival <1 month, no mastectomy, or missing lymph node status. Primary outcome was 5-year overall survival (OS). For univariate significant predictors, RPA were used to determine the risk groups. Among the 11,349 eligible patients, we identified 4 prognostic factors (including LNR) for survival, resulting in 8 terminal nodes. The LNR cutoffs were 0.038, 0.259, and 0.738, which divided LNR into 4 categories: very low (LNR ≤ 0.038), low (0.038 < LNR ≤ 0.259), moderate (0.259 < LNR ≤ 0.738), and high (0.738 < LNR). Then, 4 risk groups were determined as follows: Class 1 (very low risk, 8,265 patients), Class 2 (low risk, 1,901 patients), Class 3 (moderate risk, 274 patients), and Class 4 (high risk, 900 patients). The 5-year OS for Class 1, 2, 3, and 4 were 93.2%, 83.1%, 72.3%, and 56.9%, respectively (P< 0.001). The hazard ratio of death was 2.70, 4.52, and 8.59 (95% confidence interval 2.32-3.13, 3.49-5.86, and 7.48-9.88, respectively) times for Class 2, 3, and 4 compared with Class 1 (P < 0.001). In conclusion, we identified the optimal cutoff LNR values based on RPA and determined the related risk groups, which successfully predict 5-year OS in breast cancer patients.

Does the extent of lymphadenectomy, number of lymph nodes, positive lymph node ratio and neutrophil-lymphocyte ratio impact surgical outcome of perihilar cholangiocarcinoma?

BACKGROUND

Lymph node (LN) status is an important predictor of survival following resection of perihilar cholangiocarcinoma (PHCCA). Controversies still exist with regard to the prognostic value of optimum extent of lymphadenectomy, total number of nodes removed, LN ratio (LNR) and neutrophil-lymphocyte ratio (NLR) on overall survival (OS) and disease-free survival (DFS) following PHCCA resection.

METHODS

From 1994 to 2010, 84 PHCCAs were resected; 78 are included in this analysis. Kaplan-Meier survival curves were studied using log-rank statistics to assess which variables affected OS and DFS. The variables that showed statistical significance (P<0.05) on Kaplan-Meier univariate analysis were subjected to multivariate analysis using Cox proportional hazards model.

RESULTS

Five-year OS for node-positive status (n=45) was 10%, whereas node-negative (n=33) OS was 41% (P<0.001). Similarly, 5-year DFS was worse in the node-positive group (8%) than in the node-negative group (36%, P=0.001). There was no difference in 5-year OS (31 vs. 12%, P=0.135) and DFS (22 vs. 16%, P=0.518) between those with regional lymphadenectomy and those who underwent regional plus para-aortic lymphadenectomy, respectively. On univariate analysis, patients with 20 or more LNs removed had worse 5-year OS (0%) when compared with those with less than 20 LNs removed (29%, P=0.047). Moderate/poor tumour differentiation, distant metastasis and LN involvement were independent predictors of OS. Positive LNR had no effect on OS. Vascular invasion and an LNR of at least 0.37 were independent predictors of DFS. NLR had no effect on OS and DFS.

CONCLUSION

Extended lymphadenectomy patients (≥20 LNs) had worse OS when compared with those with more limited (<20 LNs) resection. An LNR of at least 0.37 is an independent predictor of DFS.

Identification of EGFR expression status association with metastatic lymph node density (ND) by expression microarray analysis of advanced gastric cancer

Metastatic lymph node density (ND) has been reproducibly proven to be a prognostic factor in gastric cancer. The molecular mechanisms that underlie this aggressiveness are underexplored. Here, we aimed to identify molecules associated with this unique phenotype. Tumor specimens from patients with stage III gastric cancer with high or low ND (n = 4 for both) were compared at the mRNA level using Affymetrix microarray (harboring 54,675 genes). The expression data were prioritized, and genes that correlated with ND were selected. Ultimately, the EGFR was validated as such a candidate molecule in patients with primary advanced gastric cancer who underwent standard treatment (n = 167). Expression data of the microarray were prioritized based on gene expression ratio and frequency of gene expression. The first priority genes to be selected were genes that are known to be amplified in cancer, which included NKX2.1, CHST9, CTNND2, SLC25A27, FGFR2, EGFR, and PTGER1. Of these genes, the EGFR gene was of particular interest. EGFR expression in primary gastric cancer was examined using immunohistochemistry (IHC). The Student's t-test elucidated a significant difference in EGFR expression between IHC 2+/3+ and IHC 1+ according to ND (P = 0.0035). The Chi-square test also indicated a significant difference between high and low levels of EGFR immunohistochemical staining (IHC2+/3+ and IHC1+, respectively) and ND status (P = 0.0023). According to the least squares method, as ND increased, the risk that EGFR staining levels changed from IHC 1+ to IHC 2+ also increased. In this study, we determined that high EGFR expression may underlie the aggressive mechanism of advanced gastric cancer with high ND.

Profiling the prognosis of gastric cancer patients: is it worth correlating the survival with the clinical/pathological and molecular features of gastric cancers?

BACKGROUND

The prognosis of gastric cancer patients still remains poor. The aim of this study was investigating the prognostic value of several clinical/pathological/molecular features in a consecutive series of gastric cancers.

METHODS

150 R0 gastrectomies plus 77 gastric cancer patients evaluated for the HER2 overexpression were selected. Survival was calculated and patients stratified according to the stage, the T-stage, the LNRs, the LNH, and the HER2 scoring system. ROC curves were calculated in order to compare the performance of the LRN and LNH systems.

RESULTS

Prognosis correlated with the stage and with the T-stage. We documented a statistical correlation between the LNRs and the survival. Conversely, a LNH > 15 did not correlate with the outcomes. The ROC curves documented a significant performance of the LRN system, whereas a statistical correlation was documented for the LNH exclusively with the endpoint of disease-free survival. We documented a trend of worse prognosis for patients with an HER2 overexpression, even though it was not of statistical value.

CONCLUSION

The LNR and the evaluation of the HER2 overexpression might be useful since they correlate with survival, might identify patients with a higher risk of recurrence, and might select patients for a tailored medical treatment.

Lymph node density in oral cavity cancer: results of the International Consortium for Outcomes Research

Background:

Lymph node density (LND) has previously been reported to reliably predict recurrence risk and survival in oral cavity squamous cell carcinoma (OSCC). This multicenter international study was designed to validate the concept of LND in OSCC.

Methods:

The study included 4254 patients diagnosed as having OSCC. The median follow-up was 41 months. Five-year overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS), locoregional control and distant metastasis rates were calculated using the Kaplan–Meier method. Lymph node density (number of positive lymph nodes/total number of excised lymph nodes) was subjected to multivariate analysis.

Results:

The OS was 49% for patients with LND⩽0.07 compared with 35% for patients with LND>0.07 (P<0.001). Similarly, the DSS was 60% for patients with LND⩽0.07 compared with 41% for those with LND>0.07 (P<0.001). Lymph node density reliably stratified patients according to their risk of failure within the individual N subgroups (P=0.03). A modified TNM staging system based on LND ratio was consistently superior to the traditional system in estimating survival measures.

Conclusion:

This multi-institutional study validates the reliability and applicability of LND as a predictor of outcomes in OSCC. Lymph node density can potentially assist in identifying patients with poor outcomes and therefore for whom more aggressive adjuvant treatment is needed.

Prognostic assessment of different metastatic lymph node staging methods for gastric cancer after D2 resection

AIM

To compare the prognostic assessment of lymph node ratio and absolute number based staging system for gastric cancer after D2 resection.

METHODS

The clinical, pathologic, and long-term follow-up data of 427 patients with gastric cancer that underwent D2 curative gastrectomy were retrospectively analyzed. The relationships between the metastatic lymph node ratio (MLR), log odds of positive lymph nodes (LODDS), and positive lymph nodes (pN) staging methods and the long-term prognoses of the patients were compared. In addition, the survival curves, accuracy, and homogeneity were compared with stratification to evaluate the prognostic assessment of the 3 methods when the number of tested lymph nodes was insufficient (< 10 and 10-15).

RESULTS

MLR [hazard ratio (HR) = 1.401, P = 0.012], LODDS (HR = 1.012, P = 0.034), and pN (HR = 1.376, P = 0.005) were independent risk factors for gastric cancer patients. The receiver operating characteristic (ROC) curves showed that the prognostic accuracy of the 3 methods was comparable (P > 0.05). Spearman correlation analysis confirmed that MLR, LODDS, and pN were all positively correlated with the total number of tested lymph nodes. When the number of tested lymph node was < 10, the value of survival curves staged by MLR and LODDS was superior to those of pN staging. However, the difference in survival curves between adjacent stages was not significant. In addition, the survival rate of stage 4 patients using the MLR and LODDS staging methods was 26.7% and 27.3% with < 10 lymph node, respectively which were significantly higher than the survival rate of patients with > 15 tested lymph nodes (< 4%). The ROC curve showed that the accuracy of the prognostic assessment of MLR, LODDS, and pN staging methods was comparable (P > 0.05), and the area under the ROC curve of all 3 methods were increased progressively with the enhanced levels of examined lymph nodes. In addition, the homogeneity of the 3 methods in patients with ≤ 15 tested lymph nodes also showed no significant difference.

CONCLUSION

Neither MLR or LODDS could reduce the staging bias. A sufficient number of tested lymph nodes is key to ensure an accurate prognosis for patients underwent D2 radical gastrectomy.

The prognostic value of harvested lymph nodes and the metastatic lymph node ratio for gastric cancer patients: results of a study of 1,101 patients

AIM

To investigate whether the recommendation to remove 15 lymph nodes that is used in the staging system is necessary to assess gastric cancer progression and to evaluate whether our metastatic lymph node ratio dividing method, adapted from the AJCC's (American Joint Committee on Cancer) 7(th) TNM staging system, is helpful for the patients with fewer than 15 harvested lymph nodes.

METHODS

We performed a retrospective study of 1101 patients with histologically diagnosed gastric cancer who underwent a D2 gastrectomy at the Sun Yat-sen University Cancer Center between January 2001 and December 2010. The Kappa and Chi-squared tests were employed to compare the clinicopathological variables. The Kaplan-Meier method and Cox regression were employed for the univariate and multivariate survival analyses.

RESULTS

In the trial, 346, 601 and 154 patients had 0-14, 15-30 and more than 30 lymph nodes harvested, respectively. The median survival times of patients with different lymph nodes harvested in N0, N1, N2 and N3a groups were 45.43, 54.28 and 66.95 months (p=0.068); 49.22, 44.25 and 56.72 months (p<0.001), 43.94, 47.97 and 35.19 months (p=0.042); 32.88, 42.76 and 23.50 months (p=0.016). Dividing the patients who had fewer than 15 lymph nodes harvested by the metastatic lymph node ratio at 0, 0.13 and 0.40, the median survival times of these 4 groups were 70.6, 50.5, 53.5 and 30.7 months (p<0.001). After re-categorising these 4 groups into the N0, N1, N2, N3a groups, the histological grade, T staging, premier N staging, and restaged N staging were the independent prognostic factors.

CONCLUSIONS

Large numbers of lymph nodes harvested in radical gastrectomy do not cause stage migration. For those patients with a small number of harvested lymph nodes, their stage should be divided by the metastatic lymph node ratio, referred to in the TNM staging system, to assign them an accurate stage.

The prognostic value of harvested lymph nodes and the metastatic lymph node ratio for gastric cancer patients: results of a study of 1,101 patients

Aim

To investigate whether the recommendation to remove 15 lymph nodes that is used in the staging system is necessary to assess gastric cancer progression and to evaluate whether our metastatic lymph node ratio dividing method, adapted from the AJCC’s (American Joint Committee on Cancer) 7^th TNM staging system, is helpful for the patients with fewer than 15 harvested lymph nodes.

Methods

We performed a retrospective study of 1101 patients with histologically diagnosed gastric cancer who underwent a D2 gastrectomy at the Sun Yat-sen University Cancer Center between January 2001 and December 2010. The Kappa and Chi-squared tests were employed to compare the clinicopathological variables. The Kaplan-Meier method and Cox regression were employed for the univariate and multivariate survival analyses.

Results

In the trial, 346, 601 and 154 patients had 0–14, 15–30 and more than 30 lymph nodes harvested, respectively. The median survival times of patients with different lymph nodes harvested in N0, N1, N2 and N3a groups were 45.43, 54.28 and 66.95 months (p = 0.068); 49.22, 44.25 and 56.72 months (p<0.001), 43.94, 47.97 and 35.19 months (p = 0.042); 32.88, 42.76 and 23.50 months (p = 0.016). Dividing the patients who had fewer than 15 lymph nodes harvested by the metastatic lymph node ratio at 0, 0.13 and 0.40, the median survival times of these 4 groups were 70.6, 50.5, 53.5 and 30.7 months (p<0.001). After re-categorising these 4 groups into the N0, N1, N2, N3a groups, the histological grade, T staging, premier N staging, and restaged N staging were the independent prognostic factors.

Conclusions

Large numbers of lymph nodes harvested in radical gastrectomy do not cause stage migration. For those patients with a small number of harvested lymph nodes, their stage should be divided by the metastatic lymph node ratio, referred to in the TNM staging system, to assign them an accurate stage.

Using the K-nearest neighbor algorithm for the classification of lymph node metastasis in gastric cancer

Accurate tumor, node, and metastasis (TNM) staging, especially N staging in gastric cancer or the metastasis on lymph node diagnosis, is a popular issue in clinical medical image analysis in which gemstone spectral imaging (GSI) can provide more information to doctors than conventional computed tomography (CT) does. In this paper, we apply machine learning methods on the GSI analysis of lymph node metastasis in gastric cancer. First, we use some feature selection or metric learning methods to reduce data dimension and feature space. We then employ the K-nearest neighbor classifier to distinguish lymph node metastasis from nonlymph node metastasis. The experiment involved 38 lymph node samples in gastric cancer, showing an overall accuracy of 96.33%. Compared with that of traditional diagnostic methods, such as helical CT (sensitivity 75.2% and specificity 41.8%) and multidetector computed tomography (82.09%), the diagnostic accuracy of lymph node metastasis is high. GSI-CT can then be the optimal choice for the preoperative diagnosis of patients with gastric cancer in the N staging.