Metastatic lymph node ratio can further stratify prognosis in rectal cancer patients treated with preoperative radiotherapy: a population-based analysis

Prognostic value of lymph node ratio in resectable rectal cancer after preoperative short-course radiotherapy-results from randomized clinical trial

PURPOSE

The value of the lymph node ratio (LNR) in patients with rectal cancer has not yet been unequivocally established. This study aims to assess the effect of the lymph node ratio on the prognosis of rectal cancer in patients operated after short-course preoperative 25 Gy radiotherapy, at 10-year follow-up.

METHODS

This is a substudy based on data from a prospective randomized clinical trial. A total of 141 patients with resectable rectal cancer were included. Lymph node yield was compared in patients with short and long time intervals between radiotherapy and surgery. Survival curves were compared between patients with different ypN and LNR categories. Univariate and multivariate analyses were performed to identify independent prognostic factors for overall survival and disease-free survival.

RESULTS

Survival and recurrence data were available for a median follow-up of 11.6 years. The lymph node yield did not differ significantly between the patients in the short- and long-interval groups. A greater difference in 10-year survival was observed in patients with LNR ≤ 0.41 and > 0.41 when compared to the ypN categories. Separate prognostic factor analyses were performed for the entire population and for subgroups that had < 12 and 12 lymph nodes resected. LNR was identified as an independent prognostic factor for overall survival, in multivariate analyses, for all patients and those with less than 12 retrieved lymph nodes.

CONCLUSION

The lymph node yield is comparable in patients with different time intervals between radiation therapy and surgery. LNR better discriminates patients in terms of overall survival than ypN categories.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT01444495, date of registration: September 30, 2011.

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.

Multislice spiral CT images combined with CEA and lymphocyte-to-neutrophil ratio predict recurrence and post-operative metastasis of rectal cancer

To explore the early predictors of post-operative recurrence and metastasis of rectal cancer, analyse the associated risk, and construct a model. Retrospective collection. Four hundred patients with rectal cancer underwent surgical resection and pathological diagnosis from September 2013 to September 2014. During the post-operative period, the patients were tested by imaging examination, serum tumour markers, and routine blood follow-up for at least 3 years. Preoperative CT examination of tumour size, lymphocyte-to-neutrophil ratio, and CEA were significant biomarkers for predicting recurrence and/or metastasis of post-operative rectal cancer. The stratified threshold of the lesion size cut-off point in CT images of patients with rectal cancer was 18.75 cm³, the cut-off point value of the lymphocyte-to-neutrophil ratio was 0.33, and the CEA cut-off point value was 16.97 ng/ml. We used the cut-off point to perform stratified survival analysis to obtain two K-M curves and conduct a log-rank test. The Cox multivariate risk regression results were as follows: preoperative CT images of lesion size, lymphocyte-to-neutrophil ratio, and CEA. The AUC of the normogram model for the prediction of post-operative recurrence and metastasis of rectal cancer is 0.939. Preoperative CT examination of tumour size can predict post-operative recurrence and metastasis of rectal cancer and can be used to analyse its risk. The lymphocyte-to-neutrophil ratio and CEA can also predict post-operative tumour recurrence and metastasis risk.

Nomograms for predicting the survival rate for cervical cancer patients who undergo radiation therapy: a SEER analysis

Aim: To integrate multiple independent risk factors to establish prognostic nomograms for better predicting overall survival and disease-specific survival in patients with cervical cancer receiving radiation therapy. Materials & methods: Cox analysis used to construct nomograms. The C-index, time-dependent receiver operating characteristic and calibration plots were used to evaluate the performance. The discrimination abilities were compared using the decision curve analysis, net reclassification improvement and integrated discrimination improvement. Results: After randomization, 2869 and 1230 cervical cancer patients were included in the training and validation sets, respectively. Nomograms that incorporated all of the significant independent factors for predicting the 3- and 5-year overall survival and disease-specific survival in the training cohort were established. Conclusion: Compared with the International Federation of Gynecology and Obstetrics staging system, the proposed nomograms exhibit superior prognostic discrimination and survival prediction.

Lymph node ratio is an independent prognostic factor for rectal cancer after neoadjuvant therapy: A meta-analysis

OBJECTIVE

With neoadjuvant therapy increasingly used in advanced rectal cancer, the lymph node ratio (LNR) has been strongly considered to indicate cancer-specific survival in recent years, and a comprehensive evaluation of a large number of studies is deficient. The objective of our study is to pool enough eligible studies to assess the relationship between LNR and prognosis of advanced rectal cancer after neoadjuvant therapy.

METHODS

A systematic search was done in the PubMed and EmBase databases (through 1 March 2017) that reported LNR in colorectal cancer after neoadjuvant therapy. The first two authors independently conducted the study selection and data extraction. All statistical analyses were conducted using STATA 13.0 (College Station, Texas).

RESULTS

Thirteen studies with 4023 participants were included in the meta-analysis, and all were published after 2011. A high LNR was assessed to be a predictor of poor overall survival in rectal cancer after neoadjuvant therapy (HR: 2.94, 95% CI:1.97 to 3.91, P < 0.001). Similarly, a high LNR was related to poor disease-free survival (HR: 2.83, 95% CI: 1.82 to 3.85, P < 0.001). With respect to recurrence, the HRs of 3.25, 1.93, and 2.11 also showed a strong relationship between high LNR and poor local, distant, and total recurrences.

CONCLUSIONS

Our present study demonstrates that a high LNR can predict poor survival in advanced rectal cancer. We suggest well-designed clinical trials to prospectively assess LNR as an independent predictor of rectal cancer survival.

The impact of the lymph node density on overall survival in patients with Wilms' tumor: a SEER analysis

OBJECTIVE

The objective of this study was to determine the impact of the lymph node density (LND) on overall survival of patients with Wilms' tumor (WT) using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Data from the SEER database were extracted from patients with WT in whom the LND could be obtained. Patients were divided into a low LND group and high LND group. Survival curves based on the LND stratification were plotted using the Kaplan-Meier method and compared with the log-rank test. The impact of prognostic factors on overall survival was analyzed using Cox regression models.

RESULTS

A total of 1,924 patients were identified from the database. Overall survival for the low LND group at 5, 10, and 20 years was significantly better than the high LND group (5-year survival: 94.1% vs 81.4%; 10-year survival: 92.6% vs 80.8%; 20-year survival: 90.6% vs 79.1%; P<0.001). In multivariate analysis, LND was a significant predictor of overall survival, regardless of whether it was a categorical variable or a continuous variable. Other significant predictors included age, race, SEER stage, and tumor laterality.

CONCLUSION

LND was a significant risk factor for overall survival of patients with WT. LND may provide a better prediction of the prognosis of WT patients and may be helpful for designing better treatments.

Preoperative lymph node size is helpful to predict the prognosis of patients with stage III gastric cancer after radical resection

OBJECTIVE

To investigate the association between preoperative lymph node size (Ns) and prognosis of radical gastrectomy for gastric cancer.

METHODS

The clinical and pathological data of 970 patients undergoing radical gastrectomy for gastric cancer were retrospectively analyzed. The correlation between Ns and the identified variables for the prediction of overall survival (OS) and disease-free survival (DFS) was examined.

RESULTS

Three hundred and thirty-one (34.1%) of 970 patients developed recurrence, which was most commonly in local lymph nodes. The average Ns was 1.52 cm in patients with recurrence, which was significantly higher than the 1.14 cm observed in patients without recurrence (p < 0.001). Patients were categorized into three groups as follows (Ns category):Ns0:≤1.10 cm, Ns1:1.10-1.70 cm, and Ns2:>1.70 cm, determined using the X-tile program. In univariate and multivariate analyses, Ns category, age, tumor size, lymphadenectomy, adjuvant chemotherapy and TNM stage were independent prognostic factors for DFS. Stratified analysis only in stage III was there a significant difference in the Ns category based on TNM stage. Furthermore, in the stage III subgroup, univariate and multivariate analyses revealed that Ns category, lymphadenectomy, and TNM stage was independent prognostic factors for DFS. A nomogram were developed to predict the 3-year DFS rate.

CONCLUSIONS

Preoperative Ns is an independent prognostic factor for DFS of patients after radical surgery for gastric cancer. The proposed nomogram combined with Ns could be a simple and effective approach to predict the 3-year DFS of stage III patients.

The prognostic value of lymph nodes count on survival of patients with node-negative gastric cancer

The retrieved lymph node (LN) count has been validated as a prognostic factor in various cancers. However, the interaction between LN counts and patients' prognosis in gastric cancer with negative-LN metastasis is not fully studied. Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer patients were used for analysis in this study. Patients operated on for gastric cancer at N0 stage between 2004 and 2012 were identified from the SEER database. The association between the LN counts and survival was assessed using the Cox proportional hazards model. Patients were stratified into 1–4, 5−13, and > 13 subgroups according to LN count cut-off values determined by X-tile program, with the 5-year cause specific survival (CSS) rate of 64.8%, 72.5%, and 79.4%, respectively. LN count was also validated as an independently prognostic factor in multivariate Cox analysis (P < 0.001). In addition, nomograms including LN counts on CSS were established according to all significant factors, and the c-index was 0.703 (95% CI: 0.672−0.734). Further study indicated that patients with no LN metastasis had a decreased risk of death for each patient with LN examined up to approximately 14 LNs. Collectively, our study firmly demonstrated that the number of the retrieved LNs count was an independent prognostic factor for gastric cancer with no LN metastasis. The higher the LN count, the better the survival would be; the best CSS was observed on the LN count more than 14.

Increased number of negative lymph nodes is associated with improved survival outcome in node positive gastric cancer following radical gastrectomy

The concept of negative lymph node (NLN) counts has recently attracted attention as a prognostic indicator in various cancer. However, the correlation between NLN counts and patient prognosis in the setting of gastric cancer is not fully studied. Surveillance, Epidemiology, and End Results Program (SEER)-registered gastric cancer patients were used for analysis in this study. Clinicopathological characteristics, including race, age, gender, and tumor stage, grade, and cause specific survival were collected. Univariate and multivariate Cox proportional hazards model were used to assess the risk factors for survival. As results, X-tile plots identified 3 and 9 as the optimal cutoff value to divide the patients into high, middle and low risk subsets in terms of cause specific survival, and NLN was validated as independently prognostic factor in mulivariate Cox analysis (P < 0.001). Further analysis showed that NLN was a prognosis factor in each N stage. Collectively, our study results firmly demonstrated that the number of NLNs was an independent prognostic factor for gastric cancer patients, and together with the N stage, it could provide more accurate prognostic information than the N stage alone.

The lymph node ratio does not provide additional prognostic information compared with the N1/N2 classification in Stage III colon cancer

AIM

The ratio of positive nodes to total nodes, the lymph node ratio (LNR), is a proposed alternative to the current N1/N2 classification of nodal disease. The true clinical benefit of adopting the LNR, however, has not been definitively demonstrated. This study compared the LNR with the current N1/N2 classification of Stage III colon cancer.

METHOD

Patients with Stage III colon cancer were identified from a prospectively maintained database (1996-2012). The specificity and sensitivity of the N1/N2 classification in the prediction of overall survival were determined using R. A cut-off point for the LNR was determined by setting the specificity the same as for the N1/N2 classification. The sensitivity of the two methods was then compared, and bootstrapping 1000-fold was performed. This was then repeated for disease-specific survival.

RESULTS

The specificity and sensitivity of the N1/N2 classification in predicting 3-year overall survival in this cohort (n = 402) was 62.2% and 52.1%, respectively. The cut-off point for the LNR was determined to be 0.27 for these data. On comparing LNR with the N1/N2 classification showed that for a given specificity, the LNR did not provide a statistically significant improvement in sensitivity (52.8% vs 52.1%, P = 0.31). For disease-specific death at 3 years, the specificity and sensitivity were 60.8% and 54.6%, respectively. The LNR did not provide a statistically significant improvement (55.4% vs 54.6%, P = 0.44).

CONCLUSION

Both the N1/N2 system and the LNR predict survival in colon cancer, but both have low specificity and sensitivity. The LNR does not provide additional prognostic value to current staging for overall or disease-specific survival for a given cut-off point.

LODDS is superior to lymph node ratio for the prognosis of node-positive rectal cancer patients treated with preoperative radiotherapy

PURPOSE

Yielding pathologic-lymph node ratio (yp-LNR) was considered to be a better staging system than yp-N stage in rectal cancer patients treated with preoperative radiotherapy (pre-RT). We aimed to compare the predictive ability of yielding pathologic log odds of positive lymph nodes (yp-LODDS) with that of yp-LNR for cancer-specific survival (CSS) in stage III rectal cancer patients treated with pre-RT.

METHODS

We analyzed stage III rectal cancer patients treated with pre-RT in the Surveillance, Epidemiology and End Results (SEER) database. Patients were classified into 4 groups, yp-LNR1 to 4, based on the LNR cutoff points 0.25, 0.50, and 0.75. Subjects were categorized into 5 groups, yp-LODDS1 to yp-LODDS5, based on the LODDS cutoff points -1, 0, 1, and 2. Univariate and multivariate Cox proportional hazards models were performed to analyze the risk factors for survival outcome.

RESULTS

A total of 4,612 patients were included from the SEER database. Patients in the yp-LNR4 group could be further divided into yp-LODDS4 and yp-LODDS5 groups with 5-year CSS of 47.6% and 31.5%, respectively (p&lt;0.001). In the multivariate analysis without yp-LODDS, yp-LNR was an independent prognostic factor (hazard ratio [HR] 2.006, 95% confidence interval [CI] 1.619-2.484, p&lt;0.001). However, after adjusting for yp-LODDS, yp-LNR was no longer associated with CSS (p = 0.393), and yp-LODDS was identified as an independent prognostic factor (HR 1.274, 95% CI 1.069-1.520, p = 0.007).

CONCLUSIONS

The prognostic value of yp-LNR can be confounded by yp-LODDS. In stage III rectal cancer patients treated with pre-RT, yp-LODDS has superior discrimination power over yp-LNR and can more accurately evaluate CSS.

LINE-1 hypomethylation in normal colon mucosa is associated with poor survival in Chinese patients with sporadic colon cancer

Genetic and epigenetic pathways are not independent in colorectal cancer (CRC) carcinogenesis. We aimed to determine the influence of various molecular features on Chinese patients' colon cancer-specific survival (CCSS). Various genetic and epigenetic modifications were detected in paired tumor and normal mucosa tissue samples. The prognostic variables regarding patient CCSS were determined. Overall, 127 patients, including 83 males and 44 females, completed a median follow-up of 65 (3–85) months. A mean LINE-1 methylation rate of 64.62% (range, 9.45–86.93) was observed. Hypermethylation at the hMLH1 gene promoter was detected in 26 (20.47%) patients. KRAS was mutated in 52 (40.94%) patients. Sixteen (12.60%) patients were confirmed as microsatellite instability (MSI)-High, and 76 (59.84%) were found to have loss of heterozygosity at 18q. The LINE-1 methylation level, MSI status, perineural invasion and distant metastases were confirmed as independent prognostic factors for patient CCSS. A stratified survival analysis further revealed that certain subgroups of patients with LINE-1 hypomethylation had significantly worse survival (all p < 0.05). Our data revealed that both genetic and epigenetic abnormalities can concurrently exist during colonic tumorigenesis. As a global epigenetic change, LINE-1 hypomethylation in normal colon mucosa might be associated with a worse outcome in certain Chinese patients with colon cancer.

The prognostic value of lymph node ratio in a national cohort of rectal cancer patients

OBJECTIVE

To analyze the prognostic implications of the lymph node ratio (LNR) in curative resected rectal cancer.

SUMMARY BACKGROUND DATA

It has been proposed that the LNR has a high prognostic impact in colorectal cancer, but the lymph node ratio has not been evaluated exclusively for rectal cancer in a large national cohort study.

METHODS

All 6793 patients in Denmark diagnosed with stage I to III adenocarcinoma of the rectum, and so treated in the period from 2003 to 2011, were included in the analysis. The cohort was divided into two groups according to whether or not neo-adjuvant treatment had been given.

RESULTS

In a multivariate analysis the pN status, ypN status and lymph node yield were found to be independent prognostic factors for overall survival, irrespective of neo-adjuvant therapy. The LNR was also found to be a significant prognostic factor with a Hazard Ratio ranging from 1.154 (95% CI: 0.930-1.432) (LNR: 0.01-0.08) to 2.974 (95% CI: 2.452-3.606) (LNR > 0.5) in the group of patients who had surgery to begin with and from 1.381 (95% CI: 0.891-2.139) (LNR: 0.01-0.08) to 2.915 (95% CI: 2.244-3.787) (LNR > 0.5) in the group of patients who had neo-adjuvant treatment.

CONCLUSIONS

The LNR reflects the influence on survival from N-status and the lymph node yield and since LNR was shown to be a significant prognostic predictor for overall survival in patients with curatively resected stage III rectal cancer irrespective of neo-adjuvant therapy we recommend that the introduction of LNR should be considered for rectal cancer in a revised TNM classification.

Increased number of negative lymph nodes is associated with improved cancer specific survival in pathological IIIB and IIIC rectal cancer treated with preoperative radiotherapy

Preoperative radiation significantly decreases the number of retrieved lymph nodes (LNs) in rectal cancer, but little is known with respect to the prognostic significance of negative LN (NLN) counts under these circumstances. In this study, Surveillance, Epidemiology, and End Results Program (SEER)-registered ypIII stage rectal cancer patients, and patients from Fudan University Shanghai Cancer Center (FDSCC) were combined and analyzed. The results showed that the survival rate of patients with n (cutoff) or more NLNs increased gradually when n ranged from two to nine. After n reached 10 or greater, survival rates were approximately equivalent. Furthermore, the optimal cutoff value of 10 was validated as an independent prognostic factor in stage ypIIIB and ypIIIC patients by both univariate and multivariate analysis (P < 0.001); the number of NLNs could also stratify the prognosis of ypN(+) patients in more detail. Patients in the FDSCC set validated these findings and confirmed that NLN count was not decreased in the good tumor regression group relative to the poor tumor regression group. These results suggest that NLN count is an independent prognostic factor for ypIIIB and ypIIIC rectal cancer patients, and, together with the number of positive LNs, this will provide better prognostic information than the number of positive LNs alone.