Prognostic Significance of the Metastatic Lymph Node Ratio in Gastric Cancer Patients

Background  

Lymph node metastasis is considered one of the most important prognostic factors in gastric cancer. However, the optimal system for accurate staging of lymph node metastasis for patients with gastric cancer remains controversial. This study was designed to investigate the prognostic significance of the metastatic lymph node ratio (MLR), which is calculated by dividing the number of metastatic lymph nodes by the total number of nodes harvested from patients with gastric cancer.     

Prognostic Significance of the Metastatic Lymph Node Ratio in Node-Positive Rectal Cancer

Background  The purpose of the study was to evaluate the prognostic value of metastatic lymph node ratio (LNR) in node-positive rectal cancer. Methods  A retrospective review was performed in 318 rectal cancer patients who received curative anterior resection in a single institution. Clinicopathological variables including LNR were studied in univariate and multivariate analyses by Cox regression. LNR was further studied when stratified by quartiles. Survival analyses were performed using the Kaplan–Meier method and log-rank test. Results  With median follow-up of 41 months, the 5-year disease-free survival (DFS) rate, overall survival (OS) rate, and local recurrence (LR) rate were 56.82%, 59.8%, and 11%, respectively. Multivariate analysis revealed that LNR as a continuous variable was the most significant prognostic factor for DFS, OS, and LR. On quartiles, LNR was stratified into three groups: <0.14, 0.14–0.49, and 0.5–1. The 5-year DFS rate was 72.57%, 58.54%, and 34.75% (P = 0.0001) and the 5-year OS rate was 72.19%, 61.92%, and 38.47% (P = 0.002) in the three groups, respectively. Five-year LR rate was significantly higher with LNR between 0.14 and 1 (3.6% in LNR<0.14 versus 15.6% in LNR 0.14–1, P = 0.019). Conclusions  LNR is an important prognostic factor for node-positive rectal cancers. With a cutoff of 0.14 and 0.5, node-positive rectal cancer patients could be categorized into three subsets with significant different outcomes.     

Prognostic Significance of Metastatic Lymph Node Ratio in T3Gastric Cancer

The fifth International Union Against Cancer tumor node metastasis (UICC TNM) classification, based on the number of metastatic lymph nodes (LN), has proved to be a reliable and objective method for predicting the prognosis of patients with gastric cancer. However, the prognosis of patients with T3 gastric cancer is still heterogeneous. This study was carried out to investigate the validity of metastatic LN ratio as a prognostic factor in T3 gastric cancer. A retrospective analysis was performed on a total of 833 patients that had either T3N1M0 (n = 504) or T3N2M0 (n = 329) gastric cancer by the fifth UICC classification. A preliminary analysis revealed the cutoff values for T3N1M0 to be 10% and for T3N2M0 to be 25%. The mean metastatic LN ratio was 9.0% for T3N1M0 cancer and 26.9% for T3N2M0 cancer. For the T3N1M0 stage, the patients who showed less than 10% of the metastatic LN ratio were grouped as N1-low with the others grouped as N1-high. For the T3N2M0 stage group, those who had less than 25% of the metastatic LN ratio were grouped as N2-low, the remainder as N2-high. The metastatic LN ratio decreased in proportion to the extent of lymphadenectomy and it increased in relation to the increasing scale of the fourth N classification. The rates of recurrence were significantly different according to the metastatic LN ratio in N1 and N2 classification of the fifth UICC classification (p < 0.05). The 5-year survival rates after gastrectomy decreased significantly by increasing the metastatic LN ratio in both T3N1M0 cancers (p =0.0026) and T3N2M0 cancers (p = 0.0057). The metastatic LN ratio was an independent risk factor for recurrence and poor prognosis. Our data suggest that the metastatic LN ratio is a significant prognostic factor for T3 gastric cancer. Furthermore, the application of the metastatic LN ratio can provide information not only about the extent of LN metastasis but also about the extent of lymphadenectomy in T3 gastric cancer.     

Prognostic Significance of the Metastatic Lymph Node Ratio in Patients with Gastric Cancer

Background  

In gastric cancer, the classification of lymph node status is still a controversial prognostic factor. Recent studies have proposed a new prognostic factor (metastatic lymph node ratio: MLR) for gastric cancer patients who undergo curative resection. The present study tested the hypothesis that MLR was better than the current pN staging system by analyzing the correlation between MLR and the International Union Against Cancer/American Joint Committee on Cancer (UICC/AJCC) staging system, by analyzing the correlation between MLR and 5-year overall survival (OS), by comparing area under the curve (AUC), and by performing univariate and multivariate analyses for OS.     

Prognostic Value of Lymph Node Yield and Metastatic Lymph Node Ratio in Medullary Thyroid Carcinoma

Introduction  Lymphadenectomy and thyroidectomy is standard treatment for medullary thyroid carcinoma (MTC), but the prognostic importance of the number of lymph nodes removed (lymph node yield, LNY) and the proportion of metastatic lymph nodes resected (metastatic lymph node ratio, MLNR) is unknown. We hypothesized that MTC survival is influenced by LNY and MLNR. Methods  Patients (N = 534) who underwent thyroidectomy with lymphadenectomy for MTC between 1988 and 2004 were identified in the Surveillance, Epidemiology, and End Results (SEER) database. The Kaplan–Meier method was used for univariate comparisons of survival for LNY and MLNR with a maximum follow-up of 12 years. Cox regression models adjusted for age, sex, extent of disease, tumor size, nodal status, LNY, and MLNR. Results  By univariate analysis, increasing LNY was associated with improved survival in all patients (P < 0.002) and node-positive patients (P < 0.001). In a multivariate analysis using LNY and MLNR as categorical variables, significant factors influencing survival included: age (P < 0.001), tumor size (P < 0.001), LNY (P = 0.007), and MLNR (P < 0.02); in node-negative patients: age (P = 0.002); in node-positive patients: age (P < 0.001), tumor size (P < 0.001), and LNY (P = 0.001). Using LNY and MLNR as continuous variables, significant factors influencing survival included: age (P < 0.001), tumor size (P < 0.001), and MLNR (P = 0.01); in node-negative patients: age (P < 0.001); in node-positive patients: age (P < 0.001) and tumor size (P < 0.001). Conclusion  In patients undergoing thyroidectomy and lymphadenectomy for MTC, LNY and MLNR predict poorer survival, but their impact on survival was limited to node-positive patients and was otherwise dominated by the effects of age and extent of disease. Supported by Grant Number KL2RR024144 from the National Center for Research Resources. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health. Presented in part at the 3rd Annual Academic Surgical Congress, February 12–15, 2008, Huntington Beach, California.     

Prognostic Significance of Metastatic Lymph Node Ratio in Node-Positive Colon Carcinoma

Background The aim of this study was to evaluate the prognostic significance of the lymph node ratio between metastatic and examined lymph nodes (LNR) in patients with stage III colon cancer. Methods A review was made of 201 patients (106 men) with stage III colon cancer of R0 resection. Lymph node (LN) disease was stratified both by the American Joint Committee on Cancer and the International Union Against Cancer nodal staging system (pN) and by quartiles of the LNR. Survival curves were made by Kaplan-Meier analysis and assessed by the log rank test. Multivariate analysis was performed by the Cox proportional hazard model. Patients ranged in age from 22 to 82 (median, 59) years with median follow-up of 52 (range, 13–96) months. Results The LNR increased as a function of the number metastatic LNs (P < .0001; 95% confidence interval [95% CI], .7155–.8265). Cutoff points of LNR quartiles to be the best separating patients with regard to 5-year disease-free survival (DFS) were between quartile 1 and 2, and between 3 and 4 (pNr1, 2, and 3); the 5-year DFS according to such stratification was 83.6%, 61.1%, and 20% in pNr1, pNr2, and pNr3, respectively (P < .0001). The Cox model identified the pNr as the most statistically significant covariate: pNr2 was three times (95% CI, 1.407–6.280) and pNr3 eight times more risky than pNr1 (95% CI, 3.739–18.704). Conclusions Ratio-based LN staging, which reflects the number of LNs examined and the quality of LN dissection, is a potent modality for prognostic stratification in patients with LN-positive colon cancer.     

Positive Lymph Node Ratio Is an Independent Prognostic Factor in Gastric Cancer After D2 Resection Regardless of the Examined Number of Lymph Nodes

The purpose of this study was to clarify the outcome of the ratio between metastatic and examined lymph nodes (N ratio) in gastric cancer patients with ≤15 examined lymph nodes after D2 lymphadenectomy. A retrospective study was performed in 906 patients with gastric cancer who had undergone D2 resection. Patients with ≤15 examined lymph nodes (group 1, n = 729) and those with >15 lymph nodes (group 2, n = 177) were analyzed separately. N ratio categories were identified as follows: N ratio 0, 0%; N ratio 1, 1% to 9%; N ratio 2, 10% to 25%; N ratio 3, >25%. Univariate analysis found that both the tumor, node, metastasis system (N staging system) and N ratio system well classified patients with significantly different prognosis. By multivariate analysis, only the N ratio classification was retained as an independent prognostic factor in both group 1 and 2 compared with the N stage system. Furthermore, when patients were divided into four groups according to the number of lymph nodes examined (1 to 3, 4 to 7, 8 to 11, and 12 to 15), the 5-year survival rates remained similar between groups according to the same N ratio (p > .05). Positive N ratio classification is a better prognostic tool compared with N staging system after D2 resection in patients with gastric cancer. It can prevent stage migration and can be used regardless of the examined number of lymph nodes. Da-zhi Xu and Qi-rong Geng contributed equally to this work.     

Lymph Node Metastasis Density and Growth Pattern as Independent Prognostic Factors in Advanced Esophageal Squamous Cell Carcinoma

BACKGROUND: Esophageal cancer is one of the leading types of cancer, and it is a particularly deadly form of malignancy. TNM classification is the most common staging system, but it has been reported that prognosis is not reflected adequately by this classification. The purpose of this study was to clarify independent prognostic factors in esophageal squamous cell carcinoma (ESCC), a dominant type of esophageal cancer in Japan, to broaden the staging system to improve its predictive value. Thus staging could be expanded to make the prognosis a valuable clinical tool, and to improve knowledge of the biological traits of advanced ESCC. METHODS: The present study included 121 patients with advanced ESCC (stage II to IVA) treated by esophagectomy between 1990 and 2003 at the Kitasato University Higashi Hospital. RESULTS: Univariate prognostic analysis of the disease-specific survival revealed that TNM stage (p < 0.0001), lymph node metastasis density over 10% (ND10; p < 0.0001), R-category (p = 0.003), intramural metastasis within the esophagus (IM; p = 0.009), growth pattern (p = 0.01), and size of tumor (p = 0.02) were significantly associated with a poor outcome in advanced ESCC. Multivariate analysis confirmed that growth pattern (p = 0.02, HR = 3.1) and ND10 (p = 0.02, HR = 2.0) were finally remnant prognostic factors independent of TNM stage. Growth pattern was prominent in stage II, whereas ND10 was directly proportional to stage progression and characteristics to stage IV disease. Interestingly, ND20, the most malignant phenotype of ESCC, was the only prognostic determinant, even in stage IV disease. CONCLUSIONS: From the present study, we concluded that progression of lymph node density is characteristic of a life-threatening phenotype of advanced ESCC, and it should be employed as a therapeutic target to improve patient survival. Growth pattern is an alternative target characteristic of less advanced ESCC. Both of these parameters may be applied as useful clinical tools in the management of patients with advanced esophageal cancer.     

Revisiting the Concept of Lymph Node Metastases of Pancreatic Head Cancer: Number of Metastatic Lymph Nodes and Lymph Node Ratio According to N Stage

Background

Some suggest that metastatic lymph node ratio (LNR) may be prognostic of survival in patients with pancreatic cancer. However, this phenomenon was confused by inclusion of node-negative patients in the analysis. The present study was designed to evaluate the prognostic impact of metastatic LNR and the absolute number of metastatic LNs in patients resected for pancreatic cancer.

Methods

Data were collected from 398 patients who underwent curative surgery for pancreatic head cancer at Seoul National University Hospital. Long-term survival was analyzed according to LNR and absolute number of metastatic LNs.

Results

Of the patients, 227 (57.0 %) had LN metastasis. The mean numbers of total retrieved and metastatic LNs were 19.5 and 1.9, respectively, and the mean LNR was 0.11. Median overall survival (OS) of patients was significantly higher in N0 than in N1 patients after curative resection (25.4 vs. 14.8 months, p < 0.001). Median OS was significantly lower in patients with 1 than in those with 0 positive LNs (17.3 vs. 25.4 months, p = 0.001). Among N1 patients, those with 0 < LNR ≤ 0.2 had comparable prognosis than those with >0.2 LNR (median OS 17.2 vs. 12.8 months, p = 0.096), and the number of metastatic LNs did not correlate with median OS (p = 0.365).

Conclusions

The presence of a single positive metastatic LN was associated with significantly poorer OS in patients with pancreatic cancer. When LN metastasis was present, the number of metastatic LNs and LNR had limited prognostic relevance.     

The Lymph Node Ratio is the Strongest Prognostic Factor after Resection of Pancreatic Cancer

Introduction  Survival after surgery of pancreatic cancer is still poor, even after curative resection. Some prognostic factors like the status of the resection margin, lymph node (LN) status, or tumor grading have been identified. However, only few data have been published regarding the prognostic influence of the LN ratio (number of LN involved to number of examined LN). We, therefore, evaluated potential prognostic factors in 182 patients after resection of pancreatic cancer including assessment of LN ratio. Methods  Since 1994, 204 patients underwent pancreatic resection for ductal pancreatic adenocarcinoma. Survival was evaluated in 182 patients with complete follow-up evaluations. Of those 182 patients, 88% had cancer of the pancreatic head, 5% of the body, and 7% of the pancreatic tail. Patients underwent pancreatoduodenectomy (85%), distal resection (12%), or total pancreatectomy (3%). Survival was analyzed by the Kaplan–Meier and Cox methods. Results  In all 204 resected patients, operative mortality was 3.9% (n = 8). In the 182 patients with follow-up, 70% had free resection margins, 62% had G1- or G2-classified tumors, and 70% positive LN. Median tumor size was 30 (7–80) mm. The median number of examined LN was 16 and median number of involved LN 1 (range 0–22). Median LN ratio was 0.1 (0–0.79). Cumulative 5-year survival (5-year SV) in all patients was 15%. In univariate analysis, a LN ratio ≥ 0.2 (5-year SV 6% vs. 19% with LN ratio < 0.2; p = 0.003), LN ratio ≥ 0.3 (5-year SV 0% vs. 18% with LN ratio < 0.3; p < 0.001), a positive resection margin (p < 0.01) and poor differentiation (G3/G4; p < 0.03) were associated with poorer survival. In multivariate analysis, a LN ratio ≥ 0.2 (p < 0.02; relative risk RR 1.6), LN ratio ≥ 0.3 (p < 0.001; RR 2.2), positive margins (p < 0.02; RR 1.7), and poor differentiation (p < 0.03; RR 1.5) were independent factors predicting a poorer outcome. The conventional nodal status or the number of examined nodes (in all patients and in the subgroups of node positive or negative patients) had no significant influence on survival. Patients with one metastatic LN had the same outcome as patients with negative nodes, but prognosis decreased significantly in patients with two or more LN involved. Conclusions  Not the lymph node involvement per se but especially the LN ratio is an independent prognostic factor after resection of pancreatic cancers. In our series, the LN ratio was even the strongest predictor of survival. The routine estimation of the LN ratio may be helpful not only for the individual prediction of prognosis but also for the indication of adjuvant therapy and herein related outcome and therapy studies. Presented in part at the 49th Annual Meeting of the Society for Surgery of the Alimentary Tract, May 2008 in San Diego and at the Annual Meeting of the German Cancer Society, February 2008 in Berlin, Germany     

Detection of Lymph Node Involvement by Cytokeratin Immunohistochemistry is an Independent Prognostic Factor After Curative Resection of Esophageal Cancer

Background  

Involved lymph nodes (LN) are a negative prognostic factor in esophageal cancers. To assess the role of nodal micrometastases, we performed immunohistochemical analyses of LN after resection of node-negative esophageal cancers and correlated the results with survival.     

淋巴结转移范围较数目能更好地反映食管癌手术治疗的预后

目的为了完善食管癌淋巴结分级,探索食管癌淋巴结转移的理想分级方法。方法回顾性分析1985年1月至1989年12月期间236例胸段食管癌切除,且淋巴结清扫数目≥6枚的患者的临床病理及随访资料,采用Cox风险比例模型筛选风险因子,Log—rank检验对按淋巴结转移数目、距离、范围的分级进行生存分析。结果患者10年随访率为92．3％（218／236）,全组总的1年、5年、10年生存率分别为80．2％、43．1％和34．2％;其中112例（47．4％）有淋巴结转移,其5年生存率低于无淋巴结转移患者（14．8％ vs．66．6％;Х^2=77．18,P=0．000）。Cox回归分析：除了侵及深度、分化程度及有无淋巴结转移外,还有淋巴结转移个数、转移距离及转移范围均为影响预后的独立危险因素。单因素Log—rank检验：按转移淋巴结数分组时,总体生存率差异有统计学意义（Х^2=96．00,P=0．000）,但N2与N3组间生存率差异无统计学意义（P〉0．05）;按淋巴结转移距离分组,总体生存率差异有统计学意义（Х^2=79．29,P=0．000）,但S1,S2,S3组间生存率差异无统计学意义（P〉0．05）;按淋巴结转移范围分组（0,1和≥2野）,总体生存率差异有统计学意义（Х^2=87．47,P=0．000）,并且各组间生存率差异亦有统计学意义（Х^2=5．14,P=0．023）。结论按照淋巴结转移的范围（无转移、1野转移、≥2野转移）来修订食管癌TNM分期的N分级,更为合理并能更好地反映食管癌切除手术患者的预后。     

Lymph Node Size and Metastatic Infiltration in Colon Cancer

Background: Detection of metastatic lymph nodes in colon cancer is essential for determining stage and adjuvant treatment modalities. Lymph node size has been used as one possible criterion for nodal metastasis. Although enlarged regional lymph nodes are generally interpreted as metastases, few data are available that correlate lymph node size with metastatic infiltration in colon cancer.Methods: In a prospective morphometric study, the regional lymph nodes from 30 colon specimens from consecutive patients with primary colon cancer were analyzed. The lymph nodes were counted and the largest diameter of each lymph node was measured and analyzed for metastatic involvement by histological examination.Results: A total of 698 lymph nodes were present in the 30 specimens examined for this study. A mean number of 23 (range, 19–39) lymph nodes was found in each specimen. Of these nodes, 566 (81%) were tumor-free and 132 (19%) contained metastases. The mean diameter of the lymph nodes free of metastases was 3.9 mm, whereas those infiltrated by metastases averaged 5.9 mm in diameter (P< 0.0001). Of the tumor-free lymph nodes, 528 (93%) measured < 5 mm in diameter, whereas 70 (53%) lymph nodes containing metastases measured < 5 mm in diameter.Conclusions: Lymph node size is not a reliable indicator for lymph node metastasis in colon cancer. A careful histological search for small lymph node metastasis in the specimen should be undertaken to avoid false-negative node staging.     

Cervical Lymph Node Dissection for Metastatic Testicular Cancer

Introduction  

Despite high response rates to systemic chemotherapy, 30% of patients with advanced stage testicular carcinoma will have extra-retroperitoneal residual masses that require resection. Most often, these are located in the lungs and mediastinum and neck. Limited data are available concerning the incidence, surgical management, and follow-up of neck metastasis arising from a testicular primary tumor.     

Prognostic Significance of Level and Number of Lymph Node Metastases in Patients with Gastric Cancer

BACKGROUND: To present data that provide some insight into the appropriateness of a nodal grouping category and its relation to survival in patients with gastric cancer. METHODS: We reviewed data of 777 patients with advanced gastric cancer who had undergone curative gastrectomy to investigate the prognostic significance of level and number of lymph node metastases. RESULTS: The prognosis of patients with gastric cancer was well correlated with the level and number of lymph node metastases. Multivariate analysis indicated that the level and number of lymph node metastases were independent prognostic indicators. Moreover, the number of lymph node metastases was an independent prognostic factor in N1, N2, and N3 patients. The most statistically significant difference in disease-specific survival was observed at a threshold of 11 lymph node metastases, yielding a chi2 value of 42.88, a hazard ratio of 2.523, at a 95% confidence interval of 1.913, 3.329 (P < .0001) by Cox proportional hazard model. On the basis of this result, patients were divided into two groups as follows: marked lymph node metastasis group (number of positive nodes > or =11) and slight lymph node metastasis group (number of positive nodes < or =10). The prognosis of patients with marked lymph node metastasis was statistically significantly worse than that with slight lymph node metastasis in N1, N2, and N3 patients. CONCLUSIONS: Both level and number were indispensable for evaluating lymph node metastasis. Therefore, addition of the number of positive nodes to the N category defined by the Japanese Classification of Gastric Carcinoma may be a useful strategy in the N staging classification in gastric cancer.