Ratio of metastatic to resected lymph nodes enhances to predict survival in patients with stage III colorectal cancer

Lymph Node Ratio as a Predictor of Survival for Colon Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Lymph node ratio is the number of lymph nodes with evidence of metastases on pathological review compared to the total number of lymph nodes harvested during oncologic resection. Lymph node ratio is a proven predictor of long-term survival. These data have not been meta-analyzed to determine the prognosis associated with different lymph node ratio cut-offs in colon cancer.

METHODS

Medline, Embase, and CENTRAL were systematically searched. Articles were included if they compared 5-year overall survival (OS) or disease-free survival (DFS) between different lymph node ratios for patients undergoing oncologic resection for stages I-III colon cancer. Pairwise meta-analyses using inverse variance random effects were performed.

RESULTS

From 2587 citations, nine studies with 97,631 patients (female: 51.9%, median age: 61.65 years) were included. A lymph node ratio above .1 resulted in a 49% decrease in the odds of 5-year OS (2 studies; OR: 0.51, 95% CI: 0.49-.53, P < .00001). A lymph node ratio above .25 resulted in a 56% decrease in the odds of 5-year OS (3 studies; OR: 0.44, 95% CI: 0.43-.45, P < .00001). A lymph node ratio above .5 resulted in a 65% decrease in the odds of 5-year OS (3 studies; OR: 0.35, 95% CI: 0.33-.37, P < .00001).

CONCLUSIONS

Lymph node ratios from .1 to .5 are effective predictors of 5-year OS for colon cancer. There appears to be an inverse dose-response relationship between lymph node ratio and 5-year OS. Further study is required to determine whether there is an optimal lymph node ratio cut-off for prognostication and whether it can inform which patients may benefit from more aggressive adjuvant therapy and follow-up protocols.

A retrospective study analyzing if lymph node ratio carbon nanoparticles predict stage III rectal cancer recurrence

Background

Lymph node ratio has garnered increasing attention as a prognostic marker for rectal cancer; however, few studies have investigated the relationship between lymph node ratio and rectal cancer recurrence. Additionally, Carbon Nanoparticle tracking is a safe and effective strategy for locating tumors and tracking lymph nodes. However, no studies have reported the relationship between Carbon Nanoparticles and rectal cancer recurrence.

Methods

Patients with stage III rectal cancer who underwent radical resection between January 2016 and 2020 were analyzed. The primary outcome was tumor recurrence. 269 patients with stage III rectal cancer were included in this study. The effects of lymph node ratio, Carbon Nanoparticles, and other clinicopathological factors on rectal cancer recurrence were assessed using univariate, multivariate analyses and the t-test.

Results

Univariate analysis determined tumor recurrence using cytokeratin 19 fragment, CA-199, CEA, N-stage, positive lymph nodes, total lymph nodes, and lymph node ratio(positive/total); with the lymph node ratio being the most relevant. Receiver operating characteristic (ROC) analysis determined lymph node ratio =0.38 as the optimal cutoff value. The analysis of lymph node ratio ≥0.38 and <0.38 showed statistical differences in three indicators: tumor recurrence, CEA, and use of Carbon Nanoparticles.

Conclusion

Lymph node ratio is a strong predictor of stage III rectal cancer recurrence and may be considered for inclusion in future tumor-node-metastasis staging and stage III rectal cancer stratification. In addition, we found that Carbon Nanoparticles use significantly increased total lymph nodes and decreased lymph node ratio.

Lymph node ratio-based nomogram for prognosis evaluation and treatment optimization of non-metastatic oral cavity squamous cell carcinoma

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LNR is an independent prognostic factor over N stage in OCSCC.

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LNR-based nomogram surpasses AJCC TNM staging in predicting outcome of OCSCC.

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LNR-based nomogram is valid in guiding post-operative radiotherapy in OCSCC.

Background

Lymph node ratio (LNR) has been increasingly reported as a prognostic factor in oral cavity squamous cell carcinoma (OCSCC). This study aimed to develop and validate a prognostic nomogram integrating LNR and to further assess its role in guiding adjuvant therapy for OCSCC.

Methods

A total of 8703 OCSCC patients treated primarily with surgery in the Surveillance, Epidemiology and End Results (SEER) database were retrieved and randomly divided into training and validation cohorts. The nomogram was created based on the factors identified by Cox model. The value of PORT and chemotherapy was respectively evaluated in each prognostic group according to nomogram-deduced individualized score.

Results

The final nomogram included tumor site, grade, T stage, number of positive lymph nodes and LNR. Calibration plots demonstrated a good match between predicted and observed rates of overall survival (OS). The concordance indexes for training and validation cohorts were 0.720 (95% confidence interval (CI): 0.708, 0.732) and 0.711 (95% CI: 0.687, 0.735), both significantly higher than did TNM stage (p< 0.001). According to individualized nomogram score, patients were stratified into three subgroups with significantly distinct outcome. PORT presented survival benefit among medium- and high-risk groups whereas a near-detrimental effect in low-risk group. Chemotherapy was found to be beneficial only in high-risk group.

Conclusion

This LNR-incorporated nomogram surpassed the conventional TNM stage in predicting prognosis of patients with non-metastatic OCSCC and identified sub-settings that could gain survival benefit from adjuvant thearpy.

Prognostic implications of ENE and LODDS in relation to lymph node-positive colorectal cancer location

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This is the first study on LODDS and ENE together. The current study showed that LODDS and ENE are liable prognostic parameters of CRC or CC.

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ENE is an independent influencing factor on the prognosis of both CRC and CC, and the prognostic impact of ENE was observed in both CRC and CC.

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The frequency of ENE increases from the proximal (right) to the distal (left) colon as well as the rectum.

Background

Extranodal extension (ENE) and log odds of positive lymph nodes (LODDS) are associated with the aggressiveness of both colon and rectal cancers. The current study evaluated the clinicopathological significance and the prognostic impact of ENE and LODDS in the colon and rectal patients independently.

Methods

The clinical and histological records of 389 colorectal cancer (CRC) patients who underwent curative surgery were reviewed.

Results

For the ENE system, 244 patients were in the ENE1 group and 145 in the ENE2 system. Compared with the ENE1 system, the patients included in the ENE2 system were prone to nerve invasion (P < 0.001) and vessel invasion (P < 0.001) with higher TNM (P = 0.009), higher T category (P = 0.003), higher N category (P < 0.001), advanced differentiation (P = 0.013), more number of positive lymph nodes (NPLN) (P < 0.001), more lymph node ratio (LNR) (P < 0.001), and a higher value of LODDS (P < 0.001). ENE was more frequent in patients with left and rectal than right cancer. For the LODDS system, 280 patients were in the LODDS1 group, and 109 in the LODDS2 group. Compared to the LODDS1 group, the patients included in the LODDS2 group were more prone to nerve invasion (P = 0.0351) and vessel invasion (P < 0.001) with a higher rate of N2 stage, less NDLN (P < 0.001), more NPLN (P < 0.001), more LNR (P < 0.001), and a higher value of ENE (P < 0.001). Based on the results in the univariable analysis, the N, NPLN, LNR, LODDS, and ENE were separately incorporated into five different Cox regression models combined with the same confounders. The multivariable Cox regression analysis demonstrated that all the five staging systems were independent prognostic factors for overall survival.

Conclusion

The current study confirmed that the LODDS stage is an independent influence on the prognosis of both CRC and CC patients. ENE is an independent influencing factor on the prognosis of both CRC and CC patients, and the prognostic impact of extracapsular lymph node was observed in both CRC and CC. The frequency of ENE increases from the proximal (right) to the distal (left) colon as well as the rectum. Therefore, combining ENE and LODDS into the current TNM system to compensate for the inadequacy of pN staging needs further investigation.

Development and validation of a prognostic nomogram for colorectal cancer after surgery

BACKGROUND

A nomogram is a diagram that aggregates various predictive factors through multivariate regression analysis, which can be used to predict patient outcomes intuitively. Lymph node (LN) metastasis and tumor deposit (TD) conditions are two critical factors that affect the prognosis of patients with colorectal cancer (CRC) after surgery. At present, few effective tools have been established to predict the overall survival (OS) of CRC patients after surgery.

AIM

To screen out suitable risk factors and to develop a nomogram that predicts the postoperative OS of CRC patients.

METHODS

Data from a total of 3139 patients diagnosed with CRC who underwent surgical removal of tumors and LN resection from 2010 to 2015 were collected from the Surveillance, Epidemiology, and End Results program. The data were divided into a training set (n = 2092) and a validation set (n = 1047) at random. The Harrell concordance index (C-index), Akaike information criterion (AIC), and area under the curve (AUC) were used to assess the predictive performance of the N stage from the American Joint Committee Cancer tumor-node-metastasis classification, LN ratio (LNR), and log odds of positive lymph nodes (LODDS). Univariate and multivariate analyses were utilized to screen out the risk factors significantly correlating with OS. The construction of the nomogram was based on Cox regression analysis. The C-index, receiver operating characteristic (ROC) curve, and calibration curve were employed to evaluate the discrimination and prediction abilities of the model. The likelihood ratio test was used to compare the sensitivity and specificity of the final model to the model with the N stage alone to evaluate LN metastasis.

RESULTS

The predictive efficacy of the LODDS was better than that of the LNR based on the C-index, AIC values, and AUC values of the ROC curve. Seven independent predictive factors, namely, race, age at diagnosis, T stage, M stage, LODDS, TD condition, and serum carcinoembryonic antigen level, were included in the nomogram. The C-index of the nomogram for OS prediction was 0.8002 (95%CI: 0.7839-0.8165) in the training set and 0.7864 (95%CI: 0.7604-0.8124) in the validation set. The AUC values of the ROC curve predicting the 1-, 3-, and 5-year OS were 0.846, 0.841, and 0.825, respectively, in the training set and 0.823, 0.817, and 0.835, respectively, in the validation test. Great consistency between the predicted and actual observed OS for the 1-, 3-, and 5-year OS in the training set and validation set was shown in the calibration curves. The final nomogram showed a better sensitivity and specificity than the nomogram with N stage alone for evaluating LN metastasis in both the training set (-4668.0 vs -4688.3, P < 0.001) and the validation set (-1919.5 vs -1919.8, P < 0.001) through the likelihood ratio test.

CONCLUSION

The nomogram incorporating LODDS, TD, and other risk factors showed great predictive accuracy and better sensitivity and specificity and represents a potential tool for therapeutic decision-making.

The prognostic value of lymph node ratio in patients with surgically resected stage I-III small-cell lung cancer: a propensity score matching analysis of the SEER database

OBJECTIVES

Due to the lack of prospective studies, the role of the lymph node ratio (LNR) in small-cell lung cancer (SCLC) remains unknown. This study aimed to assess the prognostic effect of LNR in surgically resected stage I-III SCLC patients.

METHODS

Clinical data of stage I-III (excluding N3 and NX) SCLC patients diagnosed between 1998 and 2016 were extracted from the Surveillance, Epidemiology and End Results database. Patients were divided into low-risk and high-risk subsets based on the LNR cut-off value of 0.15 using X-tile software. Propensity score matching analysis was employed to reduce bias in baseline characteristics. Kaplan-Meier analysis was performed to determine the overall survival (OS) and lung cancer-specific survival (LCSS). Cox regression analysis was performed to evaluate the effects of multiple variables.

RESULTS

A total of 978 patients were identified, of whom 669 (68.40%) had LNR ≤0.15. Patients with LNR ≤0.15 showed better OS (P < 0.001) and LCSS (P < 0.001) both before and after propensity score matching. Multivariable analyses of the matched population confirmed LNR as an independent prognostic factor. Patients with LNR >0.15 showed poorer OS [hazard ratio (HR) 1.55, 95% confidence interval (CI) 1.09-2.19; P = 0.015] and LCSS (HR 1.65, 95% CI 1.13-2.43; P = 0.010). Subgroup analyses revealed that LNR ≤0.15 was associated with favourable OS (P = 0.009 and 0.197, respectively) and LCSS (P = 0.010 and 0.169, respectively) in N1 and N2 patients.

CONCLUSIONS

LNR was determined as an independent predictor for surgically resected stage I-III SCLC, indicating that higher LNR is associated with reduced survival. The predictive value of LNR should to be further validated in prospective studies.

Metastatic lymph node ratio as a better prognostic tool than the TNM system in colorectal cancer

Background: The minimum number of lymph nodes that should be evaluated in colon cancer to adequately categorize lymph node status is still controversial. The lymph node ratio (LNR) may be a better prognostic indicator. Materials & methods: We studied 1065 patients treated from 1 January 2000 to 31 August 2012. Results: Significant differences in survival were detected according to regional lymph nodes (pN) (p < 0.001) and LNR (p < 0.001). LRN and pN are independent prognostic factors. Spearman correlation analysis showed a significant correlation between the total number of dissected lymph nodes and pN (rs = 0.167; p < 0.001), but the total number of dissected lymph nodes is not significantly correlated with LNR (rs = -0.019; p = 0.550). Interpretation: In this study, LNR seems to demonstrate a superior prognostic value compared with the pN categories, in part due to its greater independence regarding the extent of lymphadenectomy.

Prognosis of colorectal cancer patients is associated with the novel log odds of positive lymph nodes scheme: derivation and external validation

Background and aim: To construct proper and externally validate cut-off points for log odds of positive lymph nodes scheme (LODDS) staging scheme in colorectal cancer (CRC). Patients and methods: The X-tile approach was used to find the cut-off points for the novel LODDS staging scheme in 240,898 patients from the Surveillance, Epidemiology and End Results (SEER) database and externally validated in 1,878 from the international multicenter cohort. Kaplan-Meier plot and multivariate Cox proportional hazard models were performed to investigate the role of the novel LODDS classification. Results: The prognostic cut-off values were determined as -2.18, and -0.23 (P< 0.001). Patients had 5-year cancer-specific survival rates of 83.8%, 57.4% and 24.4% with increasing LODDS (P< 0.001) in the SEER database. Five-year overall survival rates were 77.2%, 55.0% and 26.7% with increasing LODDS (P< 0.001) in the external international multicenter cohort. Multivariate survival analysis identified both the LODDS classification, the patient's age, the T category, the M status, and the tumor grade as independent prognostic factors in both two independent databases. The analyses of the subgroup of patients stratified by tumor location (colon or rectum), number of retrieved lymph node (< 12 or ≥ 12), TNM stage III, lymph node-negative also confirmed the LODDS as independent prognostic factors (P< 0.001) in both two independent databases. Conclusions: The novel LODDS classification was an independent prognostic factor for patients with CRCs and should be calculated for additional risk group stratification with pN scheme.

Prognostic Value of Lymphovascular Invasion in Patients with Stage III Colorectal Cancer: A Retrospective Study

Background

Lymph node metastasis and tumor progression depend on lymphovascular invasion (LVI). This study aimed to investigate the prognostic role of LVI in patients with stage III colorectal cancer (CRC) and to develop a prognostic nomogram.

Material/Methods

A retrospective study included 437 patients with stage III CRC. The impact of LVI on overall survival (OS) was analyzed with the Kaplan-Meier method and Cox regression model. A nomogram was constructed, and its predictive accuracy was evaluated using the concordance index (C-index) and the calibration plot.

Results

LVI was found in 19.7% of cases of stage III CRCs and was significantly correlated with high tumor grade (poor differentiation) and advanced tumor stage (all P<0.05). Patients age, a family history of cancer in a first-degree relative, pre-treatment levels of carcinoembryonic antigen (CEA), prognostic nutritional index (PNI), histological tumor grade, tumor-node-metastasis (TNM) stage, and LVI were independent prognostic indicators (all P<0.05). Compared with the LVI(−) group, patients in the LVI(+) group showed a 1.748-fold increased risk of death (P=0.004) and a significantly reduced OS rate (P<0.001). In the prognostic nomogram, the C-index was significantly increased with LVI compared with the TNM stage alone (0.742 vs. 0.593; P<0.001). Calibration plots showed good fitness of the nomogram for prediction of survival. Comparison of the nomograms with and without LVI showed that inclusion of LVI improved the C-index from 0.715 to 0.742.

Conclusions

LVI was an indicator of more aggressive biological behavior and poor prognosis in patients with stage III CRC.

Comparison of Oncologic Outcomes in Laparoscopic versus Open Surgery for Non-Metastatic Colorectal Cancer: Personal Experience in a Single Institution

The oncologic merits of the laparoscopic technique for colorectal cancer surgery remain debatable. Eligible patients with non-metastatic colorectal cancer who were scheduled for an elective resection by one surgeon in a medical institution were randomized to either laparoscopic or open surgery. During this period, a total of 188 patients received laparoscopic surgery and the other 163 patients received the open approach. The primary endpoint was cancer-free five-year survival after operative treatment, and the secondary endpoint was the tumor recurrence incidence. Besides, surgical complications were also compared. There was no statistically significant difference between open and laparoscopic groups regarding the average number of lymph nodes dissected, ileus, anastomosis leakage, overall mortality rate, cancer recurrence rate, or cancer-free five-year survival. Even though performing a laparoscopic approach used a significantly longer operation time, this technique was more effective for colorectal cancer treatment in terms of shorter hospital stay and less blood loss. Meanwhile, fewer patients receiving the laparoscopic approach developed postoperative urinary tract infection, wound infection, or pneumonia, which reached statistical significance. For non-metastatic colorectal cancer patients, laparoscopic surgery resulted in better short-term outcomes, whether in several surgical complications and intra-operative blood loss. Though there was no significant statistical difference in terms of cancer-free five-year survival and tumor recurrence, it is strongly recommended that patients undergo laparoscopic surgery if not contraindicated.

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.

Survival nomograms for stage III colorectal cancer

The postoperative survival of patients with stage III colorectal cancer (CRC) various obviously. We sought to develop novel nomograms for predicting the survival of these patients after radical surgery and postoperative chemotherapy.A total of 620 consecutive patients with stage III CRC who underwent curative resection and postoperative chemotherapy between January 2009 and December 2015 were retrospectively collected and randomly allocated to the training (n = 372) or validation cohort (n = 248). Clinicopathological factors were collected and analyzed. On the basis of data from 372 patients in the training set, predictive factors for overall survival (OS) and disease-free survival (DFS) were identified using multivariate Cox regression and used to construct nomograms. The predictive performance of the nomograms was assessed by concordance index (C-index) and calibration plots. An external cohort of 248 patients was used to validate the nomograms. Furthermore, nomogram performance was compared with the performance of T and N stage stratification.Tumor differentiation grade, lymph node metastasis ratio, intravascular emboli (IVE), preoperative serum carcinoembryonic antigen (CEA) level, albumin to globulin ratio (AGR), T stage and N stage were significant prognostic factors for OS on multivariate analysis; whereas, Tumor differentiation grade, lymph node metastasis ratio, IVE, AGR and N stage were significant for DFS. Nomograms to predict 3- and 5-year OS and DFS were established that performed well (C-indexes of 0.734 [95% CI, 0.691-0.779] for OS and 0.699 [95% CI, 0.657-0.740] for DFS prediction), and nomogram accuracy was confirmed in the validation cohort. Furthermore, model comparison proved that the nomograms were superior to risk stratification by T and N stage for stage III CRC.We propose 2 practical nomograms for stage III CRC patients that provide more accurate prognostic predictions and should be helpful for guiding individualized treatment and postoperative surveillance.

Evaluation on prognostic efficacy of lymph nodes ratio (LNR) and log odds of positive lymph nodes (LODDS) in complicated colon cancer: the first study in emergency surgery

BACKGROUND

Lymph node involvement is one of the most important prognostic factors in colon cancer. Twelve is considered the minimum number of lymph nodes necessary to retain reliable tumour staging, but several factors can potentially influence the lymph node harvesting. Emergent surgery for complicated colon cancer (perforation, occlusion, bleeding) could represent an obstacle to reach the benchmark of 12 nodes with an accurate lymphadenectomy. So, an efficient classification system of lymphatic involvement is crucial to define the prognosis, the indication to adjuvant therapy and the follow-up. This is the first study with the aim to evaluate the efficacy of lymph nodes ratio (LNR) and log odds of positive lymph nodes (LODDS) in the prognostic assessment of patients who undergo to urgent surgery for complicated colonic cancer.

METHODS

This is a retrospective study carried out on patients who underwent urgent colonic resection for complicated cancer (occlusion, perforation, bleeding, sepsis). We collected clinical, pathological and follow-up data of 320 patients. Two hundred two patients met the inclusion criteria and were distributed into three groups according to parameter N of TNM, LNR and LODDS. Survival analysis was performed by Kaplan-Meier curves, investigating both overall survival (OS) and disease-free survival (DFS).

RESULTS

The median number of harvested lymph nodes was 17. In 78.71% (n = 159) of cases, at least 12 lymph nodes were examined. Regarding OS, significant differences from survival curves emerged for ASA score, surgical indication, tumour grading, T parameter, tumour stage, N parameter, LNR and LODDS. In multivariate analysis, only LODDS was found to be an independent prognostic factor. Concerning DFS, we found significant differences between survival curves of sex, surgical indication, T parameter, tumour stage, N parameter, LNR and LODDS, but none of these confirmed its prognostic power in multivariate analysis.

CONCLUSIONS

We found that N, LNR and LODDS are all related to 5-year OS and DFS with statistical significance, but only LODDS was found to be an independent prognostic factor for OS in multivariate analysis.

The prognostic significance of lymph node size in node-positive colon cancer

OBJECTIVES

To (i) show the outcome benefits of enlarged lymph nodes in node-positive colon cancer cases, as it was shown previously in negative node cases; (ii) disprove the stage migration theory and (iii) list the factors affecting lymph node size and yield.

METHODS

A retrospective study including 234 node-positive colon cancer cases was scheduled and performed. All recovered lymph nodes (6969) from 234 cases were microscopically examined in regard to (a) lymph node size (b) presence of metastasis (c) extent of intra-nodal metastasis. On the basis of resulting data, a statistical analysis was performed.

RESULTS

Metastases occurred in all size categories, though more often in larger lymph nodes. Fifty-one percent of all metastasised nodes were 2 to 6 mm in size. Approximately half of all nodes >10 mm were microscopically free of cancer. Cases with a small lymph node metastasis to lymph node size ratio (MSR) had a better prognosis than others: 85 months (95% CI: 72-97) vs. 67 months (95% CI: 47-88), p <0.001 (mean, overall survival). To differentiate between cases with the same ratio but different absolute lymph nodes sizes, we divided the cases into two groups that differed in their number of moderate to large lymph nodes. The group with more moderate to large lymph nodes showed a clear outcome benefit: 104 months (95% CI: 86-122) vs. 66 months (95% CI: 54-77), p = 0.014 (mean, overall survival).

CONCLUSIONS

Metastasised lymph nodes affect all size categories, and large lymph nodes are not always metastasised. The combination of enlarged lymph nodes and a small lymph node metastasis to lymph node size ratio (MSR) is associated with a better prognosis than others. When enlarged lymph nodes were considered as surrogate markers of an effective local immune response due to nodal hyperplasia, the immune system could be seen as the confounder affecting both lymph node size and prognosis. Our results are pointing in this direction and, along with other reasons, are challenging the stage migration theory.

Impact of lymph node ratio on survival in stage III ovarian high-grade serous cancer: a Turkish Gynecologic Oncology Group study

Objective

The purpose of this study was to investigate the prognostic value of lymph node ratio (LNR) in patients with stage III ovarian high-grade serous carcinoma (HGSC).

Methods

A multicenter, retrospective department database review was performed to identify patients with ovarian HGSC at 6 gynecologic oncology centers in Turkey. A total of 229 node-positive women with stage III ovarian HGSC who had undergone maximal or optimal cytoreductive surgery plus systematic lymphadenectomy followed by paclitaxel plus carboplatin combination chemotherapy were included. LNR, defined as the percentage of positive lymph nodes (LNs) to total nodes recovered, was stratified into 3 groups: LNR1 (<10%), LNR2 (10%≤LNR<50%), and LNR3 (≥50%). Kaplan-Meier method was used to generate survival data. Factors predictive of outcome were analyzed using Cox proportional hazards models.

Results

Thirty-one women (13.6%) were classified as stage IIIA1, 15 (6.6%) as stage IIIB, and 183 (79.9%) as stage IIIC. The median age at diagnosis was 56 (range, 18–87), and the median duration of follow-up was 36 months (range, 1–120 months). For the entire cohort, the 5-year overall survival (OS) was 52.8%. An increased LNR was associated with a decrease in 5-year OS from 65.1% for LNR1, 42.5% for LNR2, and 25.6% for LNR3, respectively (p<0.001). In multivariate analysis, women with LNR≥0.50 were 2.7 times more likely to die of their tumors (hazard ratio [HR]=2.7; 95% confidence interval [CI]=1.42–5.18; p<0.001).

Conclusion

LNR seems to be an independent prognostic factor for decreased OS in stage III ovarian HGSC patients.

Lymph Node Ratio as a Risk Factor for Recurrence After Adjuvant Chemotherapy in Stage III Colorectal Cancer

BACKGROUND

Although several markers, including the lymph node ratio (LNR), have been proposed as a clinically prognostic tool for colorectal cancer (CRC), it remains unclear which markers have the most relevance in determining recurrence following adjuvant chemotherapy for stage III CRC.

METHODS

Independent risk factors for recurrence-free survival (RFS) were retrospectively determined using the Cox proportional hazard model in 360 stage III CRC patients and validated using an independent cohort comprising 172 stage III CRC patients.

RESULTS

The LNR was independently associated with RFS (HR, 1.96; 95% CI, 1.11 to 3.28; P = 0.020). A higher LNR value was significantly associated with recurrence, microsatellite stable, and shorter time to recurrence. A combination of the LNR with pre-chemotherapy CEA and CA19-9, other independent risk factors, provided accurate risk stratification of RFS and conferred additional information on recurrence within each stage III CRC subgroup, which was then validated in an independent cohort. A beneficial effect in patients at risk of recurrence, and a reduced effect in patients at low risk, was exhibited by the addition of oxaliplatin to 5-fluorouracil-based adjuvant chemotherapy.

CONCLUSION

A higher LNR is one of the most aggressive phenotypes with recurrence risk following adjuvant chemotherapy for stage III CRC.

Log odds of positive lymph nodes is superior to the number- and ratio-based lymph node classification systems for colorectal cancer patients undergoing curative (R0) resection

The metastatic lymph node status (N classification) is an important prognostic factor for patients with colorectal cancer (CRC). The aim of the present study was to evaluate and compare the prognostic assessment of three different lymph node staging methods, namely standard lymph node (pN) staging, metastatic lymph node ratio (LNR) and log odds of positive lymph nodes (LODDS) in CRC patients who undergo curative resection (R0). Data were retrospectively collected from 192 patients who had undergone R0 resection. Kaplan-Meier survival curves, Cox proportional hazards model and accuracy of the three methods (pN, LNR and LODDS) were compared to evaluate the prognostic effect. Univariate analysis demonstrated that pN, LNR and LODDS were all significantly correlated with survival (P=0.001, P<0.001 and P<0.001, respectively). The final result of the 3-step multivariate analysis demonstrated that LODDS was superior to the other two N categories. Patients in the same pN or LNR classifications may be classified into different LODDS stages with different prognoses. Thus, LODDS may be a meaningful prognostic indicator and superior to the pN and LNR classifications in CRC patients who undergo curative (R0) resection.

Prognostic significance of lymph node metastasis in esophageal squamous cell carcinoma

Prediction of lymph node metastasis in esophageal squamous cell carcinoma (ESCC) is very important to have prognostic significance. The objective of this study which involved a relatively large number of ESCC patients was to investigate the correlated factors for lymph node metastasis and prognosis in ESCC. We analyzed a retrospective review of 446 patients with ESCC treated by esophagectomy between January 2010 and July 2016. The relationship between lymph node metastasis and clinicopathological parameters were analyzed. The association between overall survival and clinicopathological factors were evaluated using univariate and multivariable Cox regression models. In the present study, 36.8% esophageal squamous cell carcinoma patients were histologically shown to have lymph node metastasis. Lymph node metastasis was closely correlated with tumor differentiation (p=0.016), perineural invasion (p=0.022), advanced stage tumor (p<0.001) and venous invasion (p<0.001). Kaplan-Meier survival analysis revealed that patients with tumor size, higher T stage, perineuronal invasion, lymph node metastasis, N stage and LNR higher than 0.2 had unfavorable prognosis (p<0.05). The univariate analysis revealed for overall survival that tumor size, pathological stage, perineuronal invasion, lymph metastasis, N stage, involved LNR were relevant prognostic indicators. Furthermore, tumor size, lymph metastasis, N stage and LNR could as independent prognostic factors.

Lymph Node Ratio and Liver Metachronous Metastases in Colorectal Cancer

The authors seek to assess whether the lymph node ratio (LNR) could predict the risk of metachronous liver metastases. Using the goal of sampling 12 lymph nodes for a proper staging of colorectal cancer is often “uncommon,” and the LNR is what allows for a better prognosis selection of patients. A homogeneous group of 280 patients, followed up for at least 5 years, was evaluated. To highlight the groups with the highest risk of metachronous liver metastases, patients were divided into 4 quartiles groups in relation to the LNR. The number of lymph nodes sampled in group “Stage I” was significantly lower. Even if statistical significance between the global LNR and the development of liver metastases has not been reached, the subdivision into quartiles has made it possible to highlight that in the more advanced ratio groups, a higher incidence of metachronous liver metastases (P &lt; 0.028) was registered and was a different distribution of patients with or without liver metastasis in function of quartiles (P = 0.01). The LNR has enabled us to prognosticate patients who are at greater risk of developing metachronous liver metastases. The lower lymph node sampling in the patients with less advanced staging (I) and in patients with node-negative cancer (I + II) who developed liver metastases, leads us to believe that some patients have been understaged. We believe that the LNR, especially in cases of adequate lymph node sampling, is a useful gauge to better substratify “node-positive” patients.

Trends in lymph node excision and impact of positive lymph node ratio in patients with colectomy for primary colon adenocarcinoma: Population based study 1988 to 2011

BACKGROUND

Studies suggest increased lymph node excision in patients with colon cancer portends improved survival. Guidelines recommend excising 12 or more lymph nodes during colectomy. There is an inverse correlation between the positive lymph node ratio and survival in patients of these patients.

OBJECTIVE

We sought to determine whether colon cancer patients have adequate lymph node excision and whether positive lymph node ratio can be used as a guiding factor for their treatment plan.

DESIGN

Retrospective, Observational.

SETTINGS

United States, 1988-2011.

PATIENTS

Utilizing the Surveillance, Epidemiology, and End Results registry, we identified 318,323 patients who underwent colectomy for colonic adenocarcinoma. Patients were stratified by age, tumor stage, tumor grade, race, ratio of positive nodes, and year of diagnosis.

MAIN OUTCOME MEASURES

We determined the percentage of patients undergoing lymph node excision and mean number of nodes excised by year of diagnosis. In patients with adequate lymph node excision, positive lymph node ratio versus overall and cancer-specific survival was evaluated.

RESULTS

302,620 patients (95%) had at least 1 lymph node excised and 164,583 patients (52%) had 12 or more lymph nodes excised. This correlates to an increase from approximately 30% in 1988 to 80% by 2011. The mean number of nodes excised doubled from 9 to 18 in the entire cohort over the timeframe studied. On multivariate analysis, the 4 year cluster of diagnosis was the largest predictor of receipt of adequate lymph node excision with a 1.68 times higher odds per 4-year increase from 1988 (95% CI 1.67-1.69, p < 0.001). Higher positive lymph node ratio correlated with significantly worse overall and cancer-specific survival in those who had 12 or more lymph nodes excised. At a positive lymph node ratio of 0.16, there is a 15.7% increased rate of cancer specific mortality.

CONCLUSIONS

Despite improvement in the performance of lymph node excision in patients undergoing colectomy for colon adenocarcinoma since 1988, only 80% of patients had adequate lymph node excision in 2011. Increasing positive lymph node ratio predicts significantly worse cancer-specific survival and a ratio of 0.16 may be considered an indication for a more aggressive therapeutic plan.

CATEGORY

Colorectal/Anal Neoplasia.

A prognostic model to predict survival in stage III colon cancer patients based on histological grade, preoperative carcinoembryonic antigen level and the neutrophil lymphocyte ratio

BACKGROUND

Stage III colon cancer patients demonstrate diverse clinical outcomes. The aim of this study was to develop a prognostic model in order to better predict their survival.

MATERIALS AND METHODS

From 2004 to 2010, 548 patients were retrospectively analyzed, among whom 328 were defined as the study group and the remaining 220 served as a validation group. Clinico-pathologic features, including age, gender, histological grade, T stage, number of positive lymph nodes, number of harvest lymph nodes, pretreatment carcinoembryonic antigen (CEA) levels and pretreatment neutrophil lymphocyte ratio (NLR), were collected. Kaplan-Meier survival curves were used to detect prognostic factors and multivariate analysis was applied to identify independent examples on which to develop a prognostic model. Finally, the model was further validated with the validation group.

RESULTS

Histological grade (p=0.002), T stage (p=0.011), number of positive lymph nodes (p=0.003), number of harvested lymph nodes (p=0.020), CEA (p=0.005), and NLR (p<0.001) were found as prognostic factors while histological grade [RR(relative risk):0.632, 95%CI (Confidence interval) 0.405~0.985, p=0.043], CEA (RR:0.644, 95%CI:0.431~0.964, p=0.033) and NLR (RR:0.384, 95%CI:0.255~0.580, p<0.001) levels were independent. The prognostic model based on these three factors was able to classify patients into high risk, intermediate and low risk groups (p<0.001), both in study and validation groups.

CONCLUSIONS

Histological grade, pretreatment CEA and NLR levels are independent prognostic factors in stage III colon cancer patients. A prognostic model based on these factors merits attention in future clinical practice.

Practice parameters for early colon cancer management: Italian Society of Colorectal Surgery (Società Italiana di Chirurgia Colo-Rettale; SICCR) guidelines

Early colon cancer (ECC) has been defined as a carcinoma with invasion limited to the submucosa regardless of lymph node status and according to the Royal College of Pathologists as TNM stage T1 NX M0. As the potential risk of lymph node metastasis ranges from 6 to 17% and the preoperative assessment of lymph node metastasis is not reliable, the management of ECC is still controversial, varying from endoscopic to radical resection. A meeting on recent advances on the management of colorectal polyps endorsed by the Italian Society of Colorectal Surgery (SICCR) took place in April 2014, in Genoa (Italy). Based on this material the SICCR decided to issue guidelines updating the evidence and to write a position statement paper in order to define the diagnostic and therapeutic strategy for ECC treatment in context of the Italian healthcare system.

The lymph node ratio optimises staging in patients with node positive colon cancer with implications for adjuvant chemotherapy

PURPOSE

The ratio of positive lymph nodes to total retrieved lymph nodes (lymph node ratio, LNR) has been proposed to be the superior prognostic score in colon cancer. This study aimed to validate LNR in a large, multi-centred population, focusing on patients that have undergone adjuvant chemotherapy.

METHODS

Analysis of a prospectively collected database (The West of Scotland Colorectal Cancer Managed Clinical Network) with 1,514 patients with colonic cancer identified that had undergone elective curative surgical resection in the 12 hospitals in the West of Scotland from 2000-2004. Variables recorded were as follows: demographics, adjuvant chemotherapy, number of lymph nodes retrieved, lymph node retrieval ≥12, number of positive lymph nodes and LNR. Follow up continued until June 2009. Univariate and multivariate analyses were performed to determine the influence of LNR on overall survival.

RESULTS

In 673 patients (44.5%), ≥12 lymph nodes were retrieved. Patients had a poorer long-term prognosis with increasing age, T stage and N stage. Retrieval of <12 lymph nodes and increasing LNR were both found to be significantly associated with poorer long-term survival, but on multivariable analysis, LNR was the only independently significant variable. In patients that had received adjuvant chemotherapy, only patients staged in the second lowest LNR group (0.05-0.19) had a significant improvement in long-term survival.

CONCLUSION

Lymph node ratio is the optimal method of assessing lymph node status and highlights the heterogeneity of patients with node positive disease, altering patient stratification with implications for adjuvant chemotherapy.

The prognostic value of lymph node ratio and updated TNM classification in rectal cancer patients with adequate versus inadequate lymph node dissection

BACKGROUND

The aim of this study was to clarify whether the lymph node ratio (LNR) is superior to the updated TNM classification regarding the prognosis of stage III rectal cancer patients who have not undergone neoadjuvant therapy. The TNM system is based on the absolute number of lymph nodes involved, and the LNR takes into account involved and examined nodes.

METHODS

In 237 patients with stage III rectal cancer, we evaluated prognostic factors for 5-year overall survival (OS), disease-free survival (DFS), and risk of distant metastases (DM) using the Kaplan-Meier method, with patients divided based on adequate versus inadequate lymph node dissection (≥12 vs. <12 lymph nodes examined). The updated TNM divides patients into four groups (1, 2-3, 4-6, and ≥7 involved nodes), while LNR divides patients into quartiles. Multivariate Cox regression analyses were performed.

RESULTS

Among patients with adequate lymph node dissection, the distributions within the two systems were in agreement in 141/178 (79.2 %, kappa 0.721), and the predictive values for OS, DFS, and DM were similar. In patients with inadequate lymph node dissection, the classifications of both systems were concordant in only 13/59 (22 %, kappa 0.021). The pN system significantly under-staged patients, while the LNR classification was a better predictor of OS, DFS, and DM.

CONCLUSIONS

In patients with adequate lymph node dissection, LNR staging does not add substantial information to the predictions of updated TNM lymph node staging. However, in patients with inadequate lymph node harvesting, the LNR compensates for the under-staging of the TNM classification and provides a better estimation of prognosis than the updated TNM system.

Colorectal cancer and lymph nodes: The obsession with the number 12

Lymphadenectomy of colorectal cancer is a decisive factor for the prognostic and therapeutic staging of the patient. For over 15 years, we have asked ourselves if the minimum number of 12 examined lymph nodes (LNs) was sufficient for the prevention of understaging. The debate is certainly still open if we consider that a limit of 12 LNs is still not the gold standard mainly because the research methodology of the first studies has been criticized. Moreover many authors report that to date both in the United States and Europe the number “12” target is uncommon, not adequate, or accessible only in highly specialised centres. It should however be noted that both the pressing nature of the debate and the dissemination of guidelines have been responsible for a trend that has allowed for a general increase in the number of LNs examined. There are different variables that can affect the retrieval of LNs. Some, like the surgeon, the surgery, and the pathology exam, are without question modifiable; however, other both patient and disease-related variables are non-modifiable and pose the question of whether the minimum number of examined LNs must be individually assigned. The lymph nodal ratio, the sentinel LNs and the study of the biological aspects of the tumor could find valid application in this field in the near future.

Prognostic value of lymph node ratios in node positive rectal cancer treated with preoperative chemoradiation

BACKGROUND

To investigate the impact of the lymph node ratio (LNR) on the prognosis of patients with locally advanced rectal cancer undergoing pre-operative chemoradiation.

METHODS

Clinicopathologic and follow up data of 128 patients with stage III rectal cancer who underwent curative resection from 1996 to 2007 were reviewed. The patients were divided into two groups according to the lymph node ratio: LNR ≤ 0.2 (n=28), and >0.2 (n=100). Kaplan-Meier and the Cox proportional hazard regression models were used to evaluate the prognostic effects according to LNR.

RESULTS

Median numbers of lymph nodes examined and lymph nodes involved by tumour were 10.3 (range 2-28) and 5.8 (range 1-25), respectively, and the median LNR was 0.5 (range, 0-1.6). The 5-year survival rate significantly differed by LNR (≤ 0.2, 69%; >0.2, 19%; Log-rank p value < 0.001). LNR was also a significant prognostic factor of survival adjusted for age, sex, post-operative chemotherapy, total number of examined lymph nodes, metastasis and local recurrence (≤ 0.2, HR=1; >0.2, HR=4.8, 95%CI=2.1-11.1) and a significant predictor of local recurrence and distant metastasis during follow-up independently of total number of examined lymph node.

CONCLUSIONS

Total number of examined lymph nodes and LNR were significant prognostic factors for survival in patients with stage III rectal cancer undergoing pre-operative chemoradiotherapy.

Proposal of a new classification for stage III colorectal cancer based on the number and ratio of metastatic lymph nodes

BACKGROUND

The objective of this retrospective study was to determine whether the current staging system for stage III colorectal cancer (CRC) is appropriate and to assess the value of the metastatic lymph node ratio (LNR) in predicting the prognosis of patients with stage III CRC.

METHODS

From 2000 to 2006 inclusively, 245 patients with stage III CRC underwent curative resection. The follow-up was closed in March 2012. Kaplan-Meier survival curves and log-rank tests were used for the survival analysis.

RESULTS

Survival time of patients with T3N1M0 was significantly better than that for patients in other subgroups of stage IIIB and similar to that of patients with stage IIIA disease. The greatest survival difference was found with 0.30 as the LNR cutoff point for patients with current stage III CRC. Survival time of patients with LNR ≤ 0.30 was significantly better than that of those with LNR > 0.30. rN1 included stage III patients with LNR ≤ 0.30, and rN2 included patients with LNR > 0.30. Survival time of patients with T4aN1(rN2)M0 staging was significantly worse than that for patients with T4aN1(rN1)M0 staging and similar to that of patients with stage IIIC CRC.

CONCLUSIONS

We propose an algorithm to incorporate LNR into the current American Joint Committee on Cancer staging system. In it the patients with T3N1M0 are excluded from the current stage IIIB and included in the stage IIIA group. Also, patients with T4aN1(rN2)M0 are excluded from the current stage IIIB group and included in the stage IIIC group.

Proposal of a new classification for stage III colorectal cancer based on the number and ratio of metastatic lymph nodes

BACKGROUND

The objective of this retrospective study was to determine whether the current staging system for stage III colorectal cancer (CRC) is appropriate and to assess the value of the metastatic lymph node ratio (LNR) in predicting the prognosis of patients with stage III CRC.

METHODS

From 2000 to 2006 inclusively, 245 patients with stage III CRC underwent curative resection. The follow-up was closed in March 2012. Kaplan-Meier survival curves and log-rank tests were used for the survival analysis.

RESULTS

Survival time of patients with T3N1M0 was significantly better than that for patients in other subgroups of stage IIIB and similar to that of patients with stage IIIA disease. The greatest survival difference was found with 0.30 as the LNR cutoff point for patients with current stage III CRC. Survival time of patients with LNR ≤ 0.30 was significantly better than that of those with LNR > 0.30. rN1 included stage III patients with LNR ≤ 0.30, and rN2 included patients with LNR > 0.30. Survival time of patients with T4aN1(rN2)M0 staging was significantly worse than that for patients with T4aN1(rN1)M0 staging and similar to that of patients with stage IIIC CRC.

CONCLUSIONS

We propose an algorithm to incorporate LNR into the current American Joint Committee on Cancer staging system. In it the patients with T3N1M0 are excluded from the current stage IIIB and included in the stage IIIA group. Also, patients with T4aN1(rN2)M0 are excluded from the current stage IIIB group and included in the stage IIIC group.

An appraisal of lymph node ratio in colon and rectal cancer: not one size fits all

BACKGROUND

Lymph node ratio (LNR) is increasingly accepted as a useful prognostic indicator in colorectal cancer. However, variations in methodology, statistical stringency and cohort composition has led to inconsistency in respect of the optimally prognostic LNR.

OBJECTIVE

The aim was to apply a robust regression-based analysis to generate and appraise LNRs optimally prognostic for colon and rectal cancer, both separately and in combination.

METHODS

LNR was established for all patients undergoing either a colonic (n = 379) or rectal (n = 160) cancer resection with curative intent. The optimal LNR associated with disease-free and overall survival were established using a classification and regression tree technique. This process was repeated separately for patients who underwent either colonic or rectal resection and for the combined cohort. Survival associated with differing LNR was estimated using the Kaplan-Meier method and compared using a log-rank test. Relationships between LNR, disease-free survival (DFS) and overall survival (OS) were further characterised using Cox regression analysis. All statistical analyses were conducted in the R programming environment, with statistical significance was taken at a level of p < 0.05.

RESULTS

Optimal LNRs differed between each cohort, when either overall or disease-free survival was considered. LNRs generated from combined cohorts also differed from those generated by individual cohorts. In relation to DFS, LNR values were obtained and included 0.18 for the colon cancer cohort and 0.19 for the rectal and combined colorectal cancer cohorts. In relation to OS, multiple LNR values were obtained for colon and combined cohorts; however, an optimal LNR was not evident in the rectal cancer cohort. Survival patterns according to LNR closely resembled those associated with standard nodal staging.

CONCLUSION

Application of a data-driven approach based on recursive partitioning generates differing lymph node ratios for colon, rectal and combined colorectal cohorts. In each cohort, LNR was similarly prognostic to standard nodal staging in respect to overall and disease-free survival. Overall survival was associated with a multiplicity of LNR values, whilst disease-free survival was associated with a single LNR only. The paper demonstrates the merits of utilising a data-driven approach to determining lymph node ratios from specific patient cohorts. Utilising such an approach enabled the generation of those LNRs that were most associated with particular survival trends in relation to overall and disease-free survival. These differed markedly for colon cancer, rectal cancer and combined cohorts. In general, the survival patterns associated with LNRs generated were similar to those observed with standard nodal staging.

Comparison of metastatic lymph node ratio staging system with the 7th AJCC system for colorectal cancer

PURPOSE

To evaluate the prognostic value and staging accuracy of the metastatic lymph node ratio (rN) staging system for colorectal cancer.

METHODS

A total of 1,127 patients with colorectal cancer who underwent curative surgery between 2000 and 2011 at our institute were analyzed. Lymph nodes status was assigned according to American Joint Committee on Cancer (AJCC) pN system and rN system. Patients with colon cancer (group 1, n = 652) and rectal cancer (group 2, n = 475) were analyzed separately.

RESULTS

The rN staging system was generated using 0.2 and 0.6 as the cutoff values of lymph node ratio and then compared with AJCC pN stages. Linear regression model revealed that the number of retrieved lymph node was related to number of metastatic lymph nodes. After a median follow-up of 46 months, the 5-year survival rates of patients with more than 12 lymph nodes (LNs) retrieved were better than cases with fewer than 12 LNs, while the differences were not obvious in rN classification.

CONCLUSIONS

The rN category is a better prognostic tool than the AJCC pN category for colorectal cancer patients after curative surgery.

Which is the most suitable classification for colorectal cancer, log odds, the number or the ratio of positive lymph nodes?

Objective

The aim of the current study was to investigate which is the most suitable classification for colorectal cancer, log odds of positive lymph nodes (LODDS) classification or the classifications based on the number of positive lymph nodes (pN) and positive lymph node ratio(LNR) in a Chinese single institutional population.

Design

Clinicopathologic and prognostic data of 1297 patients with colorectal cancer were retrospectively studied. The log-rank statistics, Cox's proportional hazards model, the Nagelkerke R² index and a Harrell's C statistic were used.

Results

Univariate and three-step multivariate analyses identified that LNR was a significant prognostic factor and LNR classification was superior to both the pN and LODDS classifications. Moreover, the results of the Nagelkerke R² index (0.130) and a Harrell's C statistic (0.707) of LNR showed that LNR and LODDS classifications were similar and LNR was a little better than the other two classifications. Furthermore, for patients in each LNR classification, prognosis was homologous between those in different pN or LODDS classifications. However, for patients in pN1a, pN1b, LODDS2 and LODDS3 classifications, significant differences in survival were observed among patients in different LNR classifications.

Conclusions

For patients with colorectal cancer, the LNR classification is more suitable than pN and LODDS classifications for prognostic assessment in a Chinese single institutional population.