N0/N1, PNL, or LNR? The effect of lymph node number on accurate survival prediction in pancreatic ductal adenocarcinoma

INTRODUCTION

We evaluated the prognostic accuracy of LN variables (N0/N1), numbers of positive lymph nodes (PLN), and lymph node ratio (LNR) in the context of the total number of examined lymph nodes (ELN).

METHODS

Patients from SEER and a single institution (MGH) were reviewed and survival analyses performed in subgroups based on numbers of ELN to calculate excess risk of death (hazard ratio, HR).

RESULTS

In SEER and MGH, higher numbers of ELN improved the overall survival for N0 patients. The prognostic significance (N0/N1) and PLN were too variable as the importance of a single PLN depended on the total number of LN dissected. LNR consistently correlated with survival once a certain number of lymph nodes were dissected (≥13 in SEER and ≥17 in the MGH dataset).

CONCLUSIONS

Better survival for N0 patients with increasing ELN likely represents improved staging. PLN have some predictive value but the ELN strongly influence their impact on survival, suggesting the need for a ratio-based classification. LNR strongly correlates with outcome provided that a certain number of lymph nodes is evaluated, suggesting that the prognostic accuracy of any LN variable depends on the total number of ELN.

Validation of the lymph node ratio as a prognostic factor in patients with N1 nonsmall cell lung cancer

BACKGROUND

The number of positive lymph nodes (LNs) has been proposed as a prognostic indicator in N1 nonsmall cell lung cancer (NSCLC). However, the number of positive LNs is confounded by the number of LNs resected during surgery. The lymph node ratio (LNR) (the ratio of the number of positive LNs divided by the number of LNs resected) can circumvent this limitation. The prognostic significance of the LNR has been demonstrated in elderly patients with NSCLC. The objective of the current study was to evaluate whether a higher LNR is a marker of worse survival in patients with NSCLC aged ≤65 years who have N1 disease.

METHODS

The Surveillance, Epidemiology, and End Results database was used to identify 4004 patients who underwent resection for N1 NSCLC. Patients were classified into 3 groups according to LNR (≤0.15, 0.16-0.5, and >0.5). Associations of the LNR with lung cancer-specific and overall mortality were evaluated using the Kaplan-Meier method. Stratified and Cox regression analyses were used to assess correlations between the LNR and survival after adjusting for other prognostic factors.

RESULTS

Unadjusted analysis indicated that a higher LNR was associated with worse lung cancer-specific survival (P < .0001) and overall survival (P < .0001). Stratified and multivariate analyses also indicated that the LNR was an independent predictor of survival after controlling for potential confounders.

CONCLUSIONS

The current results confirmed that the LNR is an independent prognostic factor for survival in patients with N1 NSCLC. This information may be used to identify patients who are at greater risk of cancer recurrence.

Nodal status, number of lymph nodes examined, and lymph node ratio: what defines prognosis after resection of colon adenocarcinoma?

BACKGROUND

Lymph node ratio (LNR) has been proposed as an optimal staging variable for colorectal cancer. However, the interactive effect of total number of lymph nodes examined (TNLE) and the number of metastatic lymph nodes (NMLN) on survival has not been well characterized.

STUDY DESIGN

Patients operated on for colon cancer between 1998 and 2007 were identified from the Surveillance, Epidemiology, and End Results database (n = 154,208) and randomly divided into development (75%) and validation (25%) datasets. The association of the TNLE and NMLN on survival was assessed using the Cox proportional hazards model with terms for interaction and nonlinearity with restricted cubic spline functions. Findings were confirmed in the validation dataset.

RESULTS

Both TNLE and NMLN were nonlinearly associated with survival. Patients with no lymph node metastasis had a decrease in the risk of death for each lymph node examined up to approximately 25 lymph nodes, while the effect of TNLE was negligible after approximately 10 negative lymph nodes (NNLN) in those with lymph node metastasis. The hazard ratio varied considerably according to the TNLE for a given LNR when LNR ≥ 0.5, ranging from 2.88 to 7.16 in those with an LNR = 1. The independent effects of NMLN and NNLN on survival were summarized in a model-based score, the N score. When patients in the validation set were categorized according to the N stage, the LNR, and the N score, only the N score was unaffected by differences in the TNLE.

CONCLUSIONS

The effect of the TNLE on survival does not have a unique, strong threshold (ie, 12 lymph nodes). The combined effect of NMLN and TNLE is complex and is not appropriately represented by the LNR. The N score may be an alternative to the N stage for prognostication of patients with colon cancer because it accounts for differences in nodal samples.

Prognostic significance of lymph node density in squamous cell carcinoma of the tongue

BACKGROUND

The prognostic significance of lymph node density in oral squamous cell carcinoma (OSCC) has been well recognized. However, its use in a specific subsite of the tongue has not been evaluated. The purpose of this study was to determine the prognostic significance of lymph node density in tongue squamous cell carcinoma (SCC).

METHODS

A retrospective analysis of 99 patients with tongue SCC who underwent primary curative resection and neck dissection was conducted. Overall survival (OS) and disease-specific survival (DSS) was used to evaluate the prognostic significance of lymph node density.

RESULTS

Lymph node density (using a cutoff of 0.06) was shown to be an independent predictor of OS and DSS. The impact of lymph node density on OS and DSS remained significant on multivariate analysis, whereas conventional nodal staging was not. An alternative staging strategy incorporating depth of invasion and lymph node density performs better than conventional TNM staging in predicting survival.

CONCLUSION

Our data suggest that lymph node density is a reliable and applicable predictor of prognosis in patients with tongue SCC. © 2015 Wiley Periodicals, Inc. Head Neck 38: E859-E866, 2016.

Galectin-4 expression is associated with reduced lymph node metastasis and modulation of Wnt/β-catenin signalling in pancreatic adenocarcinoma

Galectin-4 (Gal-4) has been recently identified as a pivotal factor in the migratory capabilities of a set of defined pancreatic ductal adenocarcinoma (PDAC) cell lines using zebrafish as a model system. Here we evaluated the expression of Gal-4 in PDAC tissues selected according to their lymph node metastatic status (N0 vs. N1), and investigated the therapeutic potential of targeting the cross-link with the Wnt signaling pathway in primary PDAC cells. Analysis of Gal-4 expression in PDACs showed high expression of Gal-4 in 80% of patients without lymph node metastasis, whereas 70% of patients with lymph node metastases had low Gal-4 expression. Accordingly, in primary PDAC cells high Gal-4 expression was negatively associated with migratory and invasive ability in vitro and in vivo. Knockdown of Gal-4 in primary PDAC cells with high Gal-4 expression resulted in significant increase of invasion (40%) and migration (50%, P<0.05), whereas enforced expression of Gal-4 in primary cells with low Gal-4 expression reduced the migratory and invasive behavior compared to the control cells. Gal-4 markedly reduces β-catenin levels in the cell, counteracting the function of Wnt signaling, as was assessed by down-regulation of survivin and cyclin D1. Furthermore, Gal-4 sensitizes PDAC cells to the Wnt inhibitor ICG-001, which interferes with the interaction between CREB binding protein (CBP) and β-catenin. Collectively, our data suggest that Gal-4 lowers the levels of cytoplasmic β-catenin, which may lead to lowered availability of nuclear β-catenin, and consequently diminished levels of nuclear CBP-β-catenin complex and reduced activation of the Wnt target genes. Our findings provide novel insights into the role of Gal-4 in PDAC migration and invasion, and support the analysis of Gal-4 for rational targeting of Wnt/β-catenin signaling in the treatment of PDAC.

Lymph node ratio predicts disease-specific survival in melanoma patients

BACKGROUND

The objectives of this analysis were to compare various measures associated with lymph node (LN) dissection and to identify threshold values associated with disease-specific survival (DSS) outcomes in patients with melanoma.

METHODS

Patients with lymph node-positive melanoma who underwent therapeutic LN dissection of the neck, axilla, and inguinal region were identified from the SEER database (1988-2005). We performed Cox multivariate analyses to determine the impact of the total number of LNs removed, number of negative LNs removed, and LN ratio on DSS. Multivariate cut-point analyses were conducted for each anatomic region to identify the threshold values associated with the largest improvement in DSS.

RESULTS

The LN ratio was significantly associated with DSS for all LN regions. The LN ratio thresholds resulting in the greatest difference in 5-year DSS were .07, .13, and .18 for neck, axillary, and inguinal regions, respectively, corresponding to 15, 8, and 6 LNs removed per positive lymph node. After adjustment for other clinicopathologic factors, the hazard ratios (HRs) were .53 (95% confidence interval [CI], .40 to .71) in the neck, .52 (95% CI, .42 to .65) in the axillary, and .47 (95% CI, .36 to .61) in the inguinal regions for patients who met the LN ratio threshold.

CONCLUSIONS

Among the prognostic factors examined, LN ratio was the best indicator of the extent of LN dissection, regardless of anatomic nodal region. These data provide evidence-based guidelines for defining adequate LN dissections in melanoma patients.

Impact of Number of Positive Lymph Nodes and Lymph Node Ratio on Survival of Women with Node-Positive Breast Cancer

Objective

This study aimed to evaluate the association of axillary lymph node ratio (LNR) and number of positive lymph nodes (pN) with the risk of breast cancer recurrence and death.

Materials and Methods

A retrospective cohort study of node-positive stage II and III breast cancer patients diagnosed and treated between 2008 and 2009 at the Brazilian National Cancer Institute (INCA), Brazil. Overall and disease-free survival curves for number of positive lymph nodes (pN) and lymph node ratio (LNR) risk groups were constructed using the Kaplan-Meier method and compared by the log-rank test. Multivariate analysis was performed using stepwise forward Cox regression models.

Results

In total, 628 women with node-positive breast cancer were included. Most patients (69.5%) had advanced clinical stage tumors (≥IIB). The median follow-up was 58 months (range: 3-92 months). The adjusted recurrence hazard of pN2 and pN3 patients was 2.47 (95% Confidence Interval [CI] 1.72-3.56) and 2.42 (1.62-3.60), respectively, compared to pN1 patients (p<0.001), while the hazard of intermediate (0.21-0.65) and high-risk (>0.65) LNR was 2.11 (1.49-3.00) and 3.19 (2.12-4.80), respectively, compared to low-risk LNR (≤0.20) patients (p<0.001). On the other hand, the hazard of death of pN2 and pN3 patients was 2.17 (1.42-3.30) and 2.41 (1.53-3.78), respectively (p<0.001), and the hazard of intermediate (0.21-0.65) and high-risk (>0.65) LNR patients was 1.70 (1.13-2.56) and 2.74 (1.75-4.28), respectively (p≤0.001).

Conclusion

Higher pN and LNR were associated with shorter disease-free survival and overall survival times.

Does the mechanism of lymph node invasion affect survival in patients with pancreatic ductal adenocarcinoma?

BACKGROUND

Lymph node metastases are prognostically significant in pancreatic ductal adenocarcinoma. Little is known about the significance of direct lymph node invasion.

AIM

The aim of this study is to find out whether direct lymph node invasion has the same prognostic significance as regional nodal metastases.

METHODS

Retrospective review of patients resected between 1/1/1993 and 7/31/2008. "Direct" was defined as tumor extension into adjacent nodes, and "regional" was defined as metastases to peripancreatic nodes.

RESULTS

Overall, 517 patients underwent pancreatic resection for adenocarcinoma, of whom 89 had one positive node (direct 26, regional 63), and 79 had two positive nodes (direct 6, regional 68, both 5). Overall, survival of node-negative patients was improved compared to patients with positive nodes (N0 30.8 months vs. N1 16.4 months; p < 0.001). There was no survival difference for patients with direct vs. regional lymph node invasion (p = 0.67). Patients with one positive node had a better overall survival compared to patients with >/=2 positive nodes (22.3 and 15 months, respectively; p < 0.001). The lymph node ratio (+LN/total LN) was prognostically significant after Cox regression (p < 0.001).

CONCLUSIONS

Isolated direct invasion occurs in 20% of patients with one to two positive nodes. Node involvement by metastasis or by direct invasion are equally significant predictors of reduced survival. Both the number of positive nodes and the lymph node ratio are significant prognostic factors.

The number and ratio of positive lymph nodes affect pancreatic cancer patient survival after neoadjuvant therapy and pancreaticoduodenectomy

AIMS

This study is to examine the significance of the number and ratio of positive nodes in post-neoadjuvant therapy pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC).

METHODS AND RESULTS

Our study population consisted of 398 consecutive PDAC patients, who completed neoadjuvant therapy and PD between 1999 and 2012. Lymph node status was classified as ypN0 (node-negative), ypN1 (1-2 positive nodes) and ypN2 (≥3 positive nodes) and correlated with disease-free survival (DFS) and overall survival (OS). The ypN0, ypN1 and ypN2 was present in 183 (46.0%), 117 (29.4%) and 98 (24.6%) patients, respectively. Additionally, 162 (40.7%) had a lymph node ratio (LNR) ≤0.19 and 53 (13.3%) had a LNR >0.19. Patients with ypN1 disease had shorter DFS and OS than those with ypN0 disease, but better DFS and OS than those with ypN2 disease (P < 0.05). Similarly, patients with a LNR ≤ 0.19 had better DFS and OS than those with a LNR > 0.19 (P < 0.001). In multivariate analysis, both the number of positive nodes and LNR were independent prognostic factors for DFS and OS.

CONCLUSIONS

Subclassification of post-therapy node-positive group into ypN1 (1-2 positive nodes) and ypN2 (≥3 positive nodes) should be incorporated into the American Joint Committee on Cancer (AJCC) staging of PDAC patients.

Prognostic value of lymph node ratio in head and neck squamous cell carcinoma

BACKGROUND

Lymph node ratio (LNR) is increasingly reported as a potential prognostic tool. The purpose of this review was to analyze the available literature on the prognostic significance of LNR in head and neck squamous cell carcinoma (HNSCC).

METHODS

A PubMed internet search was performed and articles meeting selection criteria were reviewed.

RESULTS

Twenty-eight studies were identified in the literature dealing with the prognostic value of LNR. The published results are variable with a range of cutoff values of LNR associated with prognosis (overall survival [OS] and/or disease-specific survival [DSS]) between 0.02 and 0.20, with an average of 0.09.

CONCLUSION

The LNR is reported to be of value in assessing prognosis in the patients with HNSCC. Although it is easy to calculate and could be considered in the staging of these patients, the currently available evidence in the literature does not yet provide a solid base for implementation.

Multi-institutional analysis of pancreatic adenocarcinoma demonstrating the effect of diabetes status on survival after resection

BACKGROUND

The effect of diabetes on survival after resection pancreatic ductal carcinoma (PDAC) is unclear. The present study was undertaken to determine whether pre-operative diabetes has any predictive value for survival.

METHODS

A retrospective review from seven centres was performed. Metabolic factors, tumour characteristics and outcomes of patients undergoing resection for PDAC were collected. Univariate and multivariable analyses were performed to determine factors associated with disease-free (DFS) and overall survival (OS).

RESULTS

Of the 509 patients in the present study, 31.2% had diabetes. Scoring systems were devised to predict OS and DFS based on a training set (n= 245) and were subsequently tested on an independent set (n= 264). Pre-operative diabetes (P < 0.001), tumour size >2 cm (P= 0.001), metastatic nodal ratio >0.1 (P < 0.001) and R1 margin (P < 0.001) all correlated with DFS and OS on univariate analysis. Scoring systems were devised based on multivariable analysis of the above factors. Diabetes and the metastatic nodal ratio were the most important factors in each system, earning two points for OS and four points for DFS. These scoring systems significantly correlated with both DFS (P < 0.001) and OS (P < 0.001).

CONCLUSION

Pre-operative diabetes status provides useful information that can help to stratify patients in terms of predicted post-operative OS and DFS.

Nodal Factors Predictive of Recurrence After Thyroidectomy and Neck Dissection for Papillary Thyroid Carcinoma

BACKGROUND

Lymph node (LN) yield and ratio are considered important predictors of post-treatment outcomes for several human cancers. This study examined the association between nodal factors, including the LN yield and ratio, with recurrence after thyroidectomy plus central compartment neck dissection (ND) for papillary thyroid carcinoma (PTC).

MATERIALS AND METHODS

This retrospective study involved 2384 consecutive patients who underwent a thyroidectomy plus central compartment ND combined with (n = 440) or without lateral compartment ND at the authors' tertiary referral center between 2006 and 2012. The number of harvested LNs, as well as other tumor and nodal findings, were carefully reviewed. Univariable and multivariable Cox proportional hazards regression models were conducted to predict recurrence and its association with clinicopathologic variables.

RESULTS

All nodal factors, including the positive number of LNs, ratio, and extranodal extension, were significantly associated with nodal and any-site recurrence after thyroidectomy, as well as the tumor size and multifocality (p < 0.01). The multivariable analysis showed that tumor size, multifocality, LN ratio, and extranodal extension were independent factors predictive of post-treatment recurrence (p < 0.05). The LN yield was higher in patients with nodal recurrence but did not significantly affect the nodal recurrence. Patients with a LN ratio >0.3 exhibited a 1.7-fold higher risk of post-treatment nodal recurrence than their counterparts (p < 0.01).

CONCLUSIONS

LN ratio is an independent determinant predictive of nodal and any-site recurrence following thyroidectomy for PTC.

Comparison of prognostic prediction between nomogram based on lymph node ratio and AJCC 8th staging system for patients with resected pancreatic head carcinoma: a SEER analysis

Background

The prognosis of pancreatic carcinoma (PC) remains poor and the American Joint Committee on Cancer (AJCC) 8th staging system for survival prediction in PC patients after curative resection is still limited. Thus, the aim of this study is to refine a valuable prognostic model and novel staging system for PC with curative resection.

Methods

The data of 3,458 patients used in this study were retrieved from the Surveillance, Epidemiology, and End Results database registry of National Cancer Institute. The prognostic value of lymph node ratio (LNR) was analyzed in the primary cohort and prognostic nomogram based on the LNR was established to create a novel staging system. Then, analyses were conducted to evaluate the application of the formulated nomogram staging system and the AJCC 8th staging system. The predictive performance of model was further validated in the internal validation cohort.

Results

Significant positive correlations were found between LNR and all factors except for surgical procedures. The results of univariate and multivariate analyses showed that LNR was identified as an independent prognostic indicator for overall survival (OS) in both primary and validation cohorts (all P < 0.001). A prognostic nomogram based on the LNR was formulated to obtain superior discriminatory abilities. Compared with the AJCC 8th staging system, the formulated nomogram staging system showed higher hazard ratios of stage II, III, and IV disease (reference to stage I disease) that were 1.637, 2.300, and 3.521, respectively, by univariate analyses in the primary cohort and the distinction between stage I, II, and III disease at the beginning or end of the survival curves was more apparent. All these results were further verified in the validation cohort.

Conclusion

LNR can be considered as a useful independent prognostic indicator for PC patients after curative resection regardless of the surgical procedures. Compared with the AJCC 8th staging system, the formulated nomogram showed superior predictive accuracy for OS and its novel staging system revealed better risk stratification.

The Prognostic Impact of the Metastatic Lymph Nodes Ratio in Colorectal Cancer

Background: This study was designed to validate the prognostic significance of the ratio of positive to examined lymph nodes (LNR) in patients with colorectal cancer. Methods: 218,314 patients from the SEER database and 1,811 patients from the three independent multicenter were included in this study. The patients were divided into 5 groups on a basis of previous published LNR: LNR0, patients with no metastatic lymph nodes; LNR1, patients with the LNR between 0.1 and 0.17; LNR2, patients with the LNR between 0.18 and 0.41; LNR3, patients with the LNR between 0.42 and 0.69; LNR4, patients with the LNR >0.7. The 5-year OS and CSS rate were estimated using Kaplan-Meier method and the survival difference was tested using log-rank test. Multivariate Cox analysis was used to further assess the influence of the LNR on patients' outcome. Results: The 5-year OS rate of patients within LNR0 to LNR4 group was 71.2, 55.8, 39.3, 22.6, and 14.6%, respectively (p < 0.001) in the SEER database. While the 5-year OS rate of those with LNR0 to LNR4 was 75.2, 66.1, 48.0, 34.0, and 17.7%, respectively (p < 0.001) in the international multicenter cohort. In the multivariate analysis, LNR was demonstrated to be a strong prognostic factor in patients with < 12 and ≥12 metastatic lymph nodes. Furthermore, the LNR had a similar impact on the patients' prognosis in colon cancer and rectal cancer. Conclusion: The LNR allowed better prognostic stratification than the positive node (pN) in patients with colorectal cancer and the cut-off values were well validated.

Patterns and prognostic value of lymph node dissection for resected perihilar cholangiocarcinoma

BACKGROUND AND AIM

Lymph node metastasis is a major prognostic factor for perihilar cholangiocarcinoma (PHC). However, prognostic significance of extent of node dissection, lymph node ratio (LNR), and number and location of positive nodes remain unclear. We aimed to evaluate whether node status, LNR, or number or location of positive nodes are independent factors for staging in PHC and to determine the minimum requirements for node examination.

METHODS

The Surveillance, Epidemiology, and End Results database was used to identify 1116 resected PHCs from 1998 to 2008. The correlation between nodal status and survival was analyzed retrospectively.

RESULTS

Lymph node metastasis occurred in 43.4% patients and was an independent predictor for overall survival and cancer-specific survival. No survival benefit was observed for an increasing number of node retrieval in node-positive patients. However, in node-negative patients, ≥13 node dissection was of more survival benefit than 3 ≤ total lymph node count (TLNC) ≤ 12 and TLNC < 3 (5-year overall survival: 52.8% vs 39.7% vs 26.3%, P = 0.001; 5-year cancer-specific survival: 60.6% vs 46.3% vs 30.0%, P = 0.001). No difference in survival between patients with regional and distant node involvement was found. Survival for patients with greater than three positive nodes was significantly worse than that for those with three or less (relative ratio: 1.466, P = 0.001). And patients with LNR > 0.27 also had unfavorable prognosis (relative ratio: 1.376, P = 0.001).

CONCLUSIONS

We determined that to adequately assess nodal status of this life-threatening disease, 13 or more nodes retrieval should be considered. Number of positive nodes and LNR rather than location of metastatic nodes may be defined as parameters for staging of PHC.

Association Between Age and Nodal Metastasis in Papillary Thyroid Carcinoma

OBJECTIVE

To determine the relationship between age and rate of lymph node metastasis, nodal burden of disease, as well as rate of lateral neck disease in papillary thyroid cancer, especially in patients aged <30 years.

STUDY DESIGN

Population-based cross-sectional study.

SETTING

Population-based cancer database.

METHODS

Data were extracted from the SEER 18 database (Surveillance, Epidemiology, and End Results) of the National Cancer Institute. The study cohort included 59,330 patients diagnosed with papillary thyroid cancer between 1988 and 2015. Patients aged 0 to 10 years, 11 to 20 years, and 21 to 30 years old were compared with those >30 years. All analyses were adjusted for sex, race, and T classification.

RESULTS

The overall rate of lymph node metastasis was 26.11%, which increased with decreasing age. Adjusted odds ratios of lymph node metastasis were 7.19 (95% CI, 3.76-13.75) for the 0- to 10-year-old group, 3.45 (95% CI, 3.08-3.87) for the 11- to 20-year-old group, and 2.28 (95% CI, 2.15-2.41) for the 21- to 30-year-old group, relative to the group >30 years old. Decreased age was also associated with increased total positive nodes, increased lymph node ratio, and increased risk of lateral neck disease.

CONCLUSION

Pediatric and early young adult patients with papillary thyroid carcinoma have a greater risk of lymph node metastasis, greater burden of nodal disease, and a greater risk of lateral neck metastases.

Prognostic markers in metastatic cutaneous squamous cell carcinoma of the head and neck

BACKGROUND

The minority of head and neck cutaneous squamous cell carcinomas (SCC) metastasize to regional lymph nodes. The purpose of this study was to describe the clinical outcomes and prognostic factors for patients with node-positive head and neck cutaneous SCC who underwent lymphadenectomy.

METHODS

We conducted a retrospective single center study using the Kaplan-Meier method for the investigation of the overall survival (OS) and locoregional control rates. The Cox proportional hazards model was evaluated to identify prognostic factors.

RESULTS

The median number of positive lymph nodes from 149 lymphadenectomies was 2 in the neck and 1 in the parotid gland. The 5-year OS and locoregional control rates were 50% and 77%, respectively. OS was worse among older patients (hazard ratio [HR], 1.04; p = .015), immunosuppressed patients (HR, 2.06; p = .034), and patients with a high total lymph node ratio (calculated from the number of positive lymph nodes divided by the total number of nodes; multivariate analysis [MVA]; HR, 1.13; p = .019).

CONCLUSION

Low total lymph node ratio is associated with improved outcomes in node-positive head and neck cutaneous SCC. © 2017 Wiley Periodicals, Inc. Head Neck 39: 772-778, 2017.

Prognostic role of the lymph node ratio in node positive colorectal cancer: a meta-analysis

The lymph node ratio (LNR) (i.e. the number of metastatic lymph nodes divided by the number of totally resected lymph nodes) has recently emerged as an important prognostic factor in colorectal cancer (CRC). However, the tumor node metastasis (TNM) staging system for colorectal cancer does not consider it as a prognostic parameter. Therefore, we conducted a meta-analysis to evaluate the prognostic role of the LNR in node positive CRC. A systematic search was performed in PubMed, Embase and the Cochrane Library for relevant studies up to November 2015. As a result, a total of 75,838 node positive patients in 33 studies were included in this meta-analysis. Higher LNR was significantly associated with shorter overall survival (OS) (HR = 1.91; 95% CI 1.71–2.14; P = 0.0000) and disease free survival (DFS) (HR = 2.75; 95% CI: 2.14–3.53; P = 0.0000). Subgroup analysis showed similar results. Based on these results, LNR was an independent predictor of survival in colorectal cancer patients and should be considered as a parameter in future oncologic staging systems.

The H19-PEG10/IGF2BP3 axis promotes gastric cancer progression in patients with high lymph node ratios

We previously demonstrated that the lymph node ratio (LNR) is a prognostic factor associated with EGFR expression, among first priority genes amplified or overexpressed in cancer. Here, we investigated the associations between high LNR and second, third, and fourth priority genes. We performed mRNA expression microarray analysis of tumor tissue from patients with stage III gastric cancer and high or low LNRs. Candidate high LNR-associated genes were further evaluated in 39 patients with stage III gastric cancer. The functional relevance of these genes was evaluated in gastric cancer cell lines. We focused on five genes: H19,PEG10, IGF2BP3, CD177, and PGA3. H19 and PEG10 were confirmed as high LNR-associated genes. H19, PEG10, and IGF2BP3 were found to promote each other’s expression. Knocking down H19 or PEG10 using RNAi decreased cell proliferation, invasion, anchorage-independent growth, and chemoresistance. These genes had a mutual relationship in MKN7 cells. H19 knockdown decreased expression of epithelial-mesenchymal transition-associated genes in MKN74 cells to suppress transformation. Thus, H19 promotes epithelial-mesenchymal transition in gastric cancer and is a potential therapeutic target.

Prognosis of patients with esophageal squamous cell carcinoma after esophagectomy using the log odds of positive lymph nodes

To compare the log odds of positive lymph nodes (LODDS) with the number of positive lymph nodes (pN), lymph node ratio (LNR), removed lymph node (RLN) count, and negative lymph node (NLN) count in determining the prognosis of patients with esophageal squamous cell carcinoma (ESCC) after esophagectomy. The records of patients with ESCC who received esophagectomy were retrospectively reviewed. The log-rank test was used to compare curves for overall survival (OS), and Cox regression analysis was performed to identify prognostic factors. The prognostic performance of the different lymph node staging systems were compared using the linear trend chi-square test, likelihood ratio chi-square test, and Akaike information criterion. A total of 589 patients were enrolled. Univariate Cox analysis showed that pN stage, LNR, RLN count, NLN count, and the LODDS were significantly associated with OS (p < 0.05 for all). Multivariate Cox analysis adjusted for significant factors indicated that LODDS was independent risk factor on overall survival (OS), and a higher LODDS was associated with worse OS (hazard ratio = 3.297, 95% confidence interval: 2.684–4.050, p < 0.001). The modified Tumor-LODDS-Metastasis staging system had better discriminatory ability, monotonicity, and homogeneity, and better optimistic prognostic stratification than the Tumor-Node-Metastasis staging system in determining the prognosis of patients with ESCC. The LODDS staging system was superior to other lymph node classifications in determining the prognosis of patients with ESCC after esophagectomy. LODDS may be incorporated into esophageal staging system if these results are eventually confirmed by other studies.

The importance of lymph node retrieval and lymph node ratio following preoperative chemoradiation of rectal cancer

AIM

Preoperative chemoradiation (CRT) for rectal cancer decreases the number of examined lymph nodes (NELN) found in the resected specimen. However, the prognostic role of lymph node evaluation including overall numbers and the lymph node ratio (LNR) in patients having preoperative CRT have not yet been defined. The study has assessed the influence of CRT on the NELN and on lymph node number and LNR on the survival of patients with rectal cancer.

METHOD

Between 2003 and 2011, 508 patients with nonmetastatic rectal cancer underwent mesorectal excision. Of these 123 (24.2%) received preoperative CRT. Univariate and multivariate analysis was performed to define the role of NELN and LNR as prognostic indicators of survival.

RESULTS

Neoadjuvant CRT significantly reduced the NELN (P < 0.0001). Disease-free survival (DFS) and overall survival (OS) of patients with fewer or more than 12 nodes retrieved did not differ statistically. Node-negative patients with six or fewer lymph nodes were significantly associated with a poor DFS and OS on univariate analysis (P = 0.03 and P = 0.03). LNR significantly influenced the DFS and OS on multivariate analysis [DFS, P = 0.0473, hazard ratio (HR) 2.4980, 95% confidence interval (CI) 1.2631-9.4097; OS, P = 0.0419, HR 1.1820, 95% CI 1.1812-10,710].

CONCLUSION

The cut-off of 12 lymph nodes does not influence survival and should not be considered for cancer-specific prediction of patients having neoadjuvant CRT. In contrast LNR is an independent prognostic predictor of DFS and OS in such patients.

Clinical relevance of lymph node ratio in breast cancer patients with one to three positive lymph nodes

BACKGROUND

To test the hypotheses that breast cancer patients with one to three positive lymph nodes (pN1) consist of heterogeneous prognostic subsets and that the ratio of positive nodes to total nodes dissected (lymph node ratio, LNR) might discriminate patients with a higher risk as candidates for post-mastectomy radiation therapy (PMRT).

METHODS

Using information from 7741 node-positive patients, we first identified cutoff values of the LNR using the nonparametric bootstrap method. Focusing on 3477 patients with pN1 disease, we then evaluated the clinical relevance of the LNR categorised by the estimated cutoff values (categorised LNR, cLNR).

RESULTS

Among 3477 patients with pN1 disease, 3059 and 418 patients were assigned into the low and intermediate cLNR groups, respectively, based on a cutoff value of 0.18. The prognostic factors associated with poor overall survival (OS) included younger age, T2 stage, negative oestrogen/progesterone receptors, high histologic grade, and intermediate cLNR. Post-mastectomy radiation therapy significantly increased OS in patients assigned to the intermediate cLNR (hazard ratio, 0.39; 95% confidence interval, 0.17-0.89; P=0.0248), whereas patients in the low cLNR group derived no additional survival benefit from PMRT.

CONCLUSION

This study suggests that PMRT should be recommended for patients with pN1 disease and an intermediate cLNR.

Predictive Value of the Number of Harvested Lymph Nodes and Cut-Off for Lymph Node Ratio in the Prognosis of Stage II and III Colorectal Cancer Patients

Purpose/aim: The appropriate staging of colorectal cancer requires at least 12 lymph nodes to be sampled. We evaluated whether lymph node sampling (LNS) and lymph node ratio (LNR) can predict the prognosis of stage II-III patients.

MATERIALS AND METHODS

This is a retrospective study on 432 patients classified in LNS ≥12 and LNS <12. Disease-free survival (DFS) was computed using the Kaplan-Meier method. We stratified stage III patients into 4 quartiles base on LNR values. To determine the optimal LNR cut-off, receiver operating characteristic (ROC) curve analysis was performed.

RESULTS

There was a positive association between the number of lymph node sampled and the number of metastatic lymph nodes (p < 0.01). Among stage II patients, the DFS was 81% for LNS ≥ 12 and 72% for LNS < 12 (p = 0.158). Among stage III patients, the DFS was 58% (p < 0.001). We found a significant association between LNR quartiles and relapse in stage III patients but only in the LNS ≥ 12 group. ROC curve analysis indicated an ideal LNR cut-off value at 0.194 (sensitivity 65% and specificity 61%). The DFS of patients with LNR below 0.194 was 71%, and that of patients with LNR above 0.194 was 45% (log-rank test, p < 0.001). In the patients with LNS ≥ 12, the cut-off of 0.257 could predict recurrence (specificity 86%).

CONCLUSIONS

Stage II patients with LNS < 12 tend to have shorter DFS than stage II patients with LNS ≥ 12. In stage III patients, an appropriate LNR cut-off is a better prognostic predictor than LNR quartile, especially in patients with LNS ≥ 12.

A high positive lymph node ratio is associated with distant recurrence after surgical resection of ampullary carcinoma

BACKGROUND

For ampullary carcinoma (AC), the lymph node ratio (LNR) has been associated with overall survival. However, the use of the LNR to predict distant recurrence risk remains unknown. The purpose of this study was to determine if the LNR is associated with distant recurrence risk.

METHODS

One hundred forty three patients with AC who underwent pancreaticoduodenectomy between 1989 and 2011 were identified from a single-institution prospective database. Data on clinicopathologic factors and recurrence were analyzed.

RESULTS

At a median follow-up of 43 months (62 months for survivors), 55 patients (38 %) had developed recurrent disease, with a median time to recurrence of 13 months. Patients with a LNR ≥ 0.15 were more likely to have T3/4 tumors, advanced stage lymphovascular (LVI), or perineural invasion (PNI) and develop recurrent disease. Univariate analysis demonstrated that T-stage, lymph node status, AJCC stage, LVI, PNI, and LNR were significantly associated with decreased time to distant recurrence (TTDR). In multivariate stepwise regression, only LNR and LVI were significantly associated with decreased TTDR.

CONCLUSIONS

A high positive LNR is associated with distant recurrence after surgical resection of AC. Given the high risk of disease recurrence, consideration for adjuvant therapy is warranted in patients with a LNR ≥ 0.15.