Inadequacy of lymph node staging in gastric cancer patients: a population-based study

Textbook Neoadjuvant Outcome-Novel Composite Measure of Oncological Outcomes among Gastric Cancer Patients Undergoing Multimodal Treatment

The incidence of gastric cancer (GC) is expected to increase to 1.77 million cases by 2040. To improve treatment outcomes, GC patients are increasingly treated with neoadjuvant chemotherapy (NAC) prior to curative-intent resection. Although NAC enhances locoregional control and comprehensive patient care, survival rates remain poor, and further investigations should establish outcomes assessment of current clinical pathways. Individually assessed parameters have served as benchmarks for treatment quality in the past decades. The Outcome4Medicine Consensus Conference underscores the inadequacy of isolated metrics, leading to increased recognition and adoption of composite measures. One of the most simple and comprehensive is the "All or None" method, which refers to an approach where a specific set of criteria must be fulfilled for an individual to achieve the overall measure. This narrative review aims to present the rationale for the implementation of a novel composite measure, Textbook Neoadjuvant Outcome (TNO). TNO integrates five objective and well-established components: Treatment Toxicity, Laboratory Tests, Imaging, Time to Surgery, and Nutrition. It represents a desired, multidisciplinary care and hospitalization of GC patients undergoing NAC to identify the treatment- and patient-related data required to establish high-quality oncological care further. A key strength of this narrative review is the clinical feasibility and research background supporting the implementation of the first and novel composite measure representing the "ideal" and holistic care among patients with locally advanced esophago-gastric junction (EGJ) and GC in the preoperative period after NAC. Further analysis will correlate clinical outcomes with the prognostic factors evaluated within the TNO framework.

Evaluation of Nationwide Trends in Nodal Sampling Guideline Adherence for Gastric Cancer: 2005-2017

INTRODUCTION

Surgical resection is the primary curative treatment for localized gastric cancer. A multitude of research supports surgical nodal sampling guidelines. Though there are known disparities in adherence to nodal sampling, it is unclear how hospital program-level disparities have changed over time. The purpose of this study is to evaluate trends in program-level disparities in adherence to gastric cancer nodal sampling guidelines.

METHODS

Patients who underwent resection of gastric cancer from 2005 to 2017 were identified in the National Cancer Database. Patients treated at academic programs were compared to those treated at nonacademic programs, and rates and trends of adherence to nodal sampling guidelines (defined as ≥15 lymph nodes) were determined. Adjusted multivariable analysis was used to determine likelihood of nodal sampling adherence while controlling for sociodemographic, clinical, hospital, and travel distance characteristics.

RESULTS

A total of 55,421 patients were included with 27,201 (49.1%) of patients meeting adherence criteria for lymph node sampling. Academic programs treated 44.4% of the total cohort. Overall, lymph node sampling criteria were met in 59.2% of patients treated at high-volume academic programs and 37.0% of patients treated at low-volume nonacademic programs (incidence rate ratios 0.67, 95% confidence interval 0.63-0.72 versus high-volume academic programs). Adherence rates improved from 2005 to 2017 for both low-volume nonacademic programs (27.8% in 2005 to 50.1% in 2017) and high-volume academic programs (46.0% in 2005 to 69.8% in 2017, P < 0.001).

CONCLUSIONS

Though adherence rates have improved from 2005 to 2017, high-volume academic programs were more likely to adhere to lymph node sampling guidelines for gastric cancer.

Short-term outcomes of D2 lymphadenectomy plus complete mesogastric excision for gastric cancer: a propensity score matching analysis

BACKGROUND

Our previous study has demonstrated the surgical advantages of D2 lymphadenectomy plus complete mesogastric excision (D2 + CME) in gastric cancer surgery. To further verify the safety of D2 + CME procedure, we conducted this large-scale, observational cohort study and applied propensity score matching (PSM) approach to compare D2 + CME with conventional D2 in terms of short-term outcomes in gastric cancer patients.

METHODS

Data on 855 patients from Tongji Hospital who underwent laparoscopic-assisted distal gastrectomy (LADG) with R0 resection (496 in the conventional D2 cohort and 359 in the D2 + CME cohort) between Dec 12, 2013 and Dec 28, 2017 were retrieved from prospectively maintained clinical database. After PSM analysis at a 1:1 ratio, each cohort included 219-matched patients. Short-term outcomes, including surgical results, morbidity, and mortality within 30 days after the operation, were collected and analyzed.

RESULTS

In this large-scale, observational cohort study based on PSM analysis, the D2 + CME procedure showed less intra-laparoscopic blood loss, more lymph node harvest, and faster postoperative flatus than the conventional D2 procedure. However, both the overall and severe postoperative adverse events (Clavien-Dindo classification grade ≥ III a) seemed comparable between two cohorts.

CONCLUSION

The present study showed that D2 + CME was associated with better short-term outcomes than conventional D2 dissection for patients with resectable gastric cancer.

Comparison of 4 lymph node staging systems for the prognostic prediction of esophagogastric junction adenocarcinoma with ≤15 retrieved lymph nodes

BACKGROUND

Directly applying the 8th American Joint Committee on Cancer (AJCC) Tumor Node Metastasis (TNM) staging system to evaluate the prognosis of patients with esophagogastric junction adenocarcinoma (AEG) might lead to under-staging, when insufficient lymph nodes were retrieved during surgery. The prognostic value of 4 lymph nodes staging systems, 8th AJCC TNM N stage, lymph node ratio (LNR), log odds of positive lymph nodes (LODDS), and negative lymph nodes (NLN), in AEG patients having ≤15 retrieved lymph nodes were compared.

METHODS

869 AEG patients diagnosed between 2004 and 2012 with ≤15 retrieved lymph nodes were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox regression analyses were conducted to assess the association of cancer-specific survival (CSS) and overall survival (OS) with 8th AJCC TNM N stage, LNR, LODDS, and NLN respectively. Predictive survival ability was assessed and compared using linear trend χ2 score, likelihood ratio (LR) test, Akaike information criterion (AIC), Harrell concordance index (C-index), and Receiver Operative Curve (ROC).

RESULTS

The N stage, LNR, LODDS, and NLN were all independent prognostic predictors for CSS and OS in multivariate Cox models. Comparatively, LODDS demonstrated higher linear trend χ2 score, LR test score, C-index and integrated area under the curve (iAUC) value, and lower AIC in CSS compared to the other three systems. Moreover, for patients without regional lymph node metastasis, NLN showed higher C-index and lower AIC.

CONCLUSIONS

LODDS showed better predictive performance than N, LNR, and NLN among patients with node-positive patients while NLN performed better in node-negative patients. A combination of LODDS and NLN has the potential to provide more prognostic information than the current AJCC TNM classification.

Role of carbon nanotracers in lymph node dissection of advanced gastric cancer and the selection of preoperative labeling time

BACKGROUND

The incidence of gastric cancer is high. The number of dissected lymph nodes was an independent factor affecting prognosis. Although preoperative labeling is helpful in lymph nodes resection, there are no guidelines for when to perform preoperative labeling.

AIM

To investigate the role of nanocarbon in lymph node dissection during gastrectomy, and to discuss the relationship between the timing of preoperative injection of carbon nanoparticles and the extent of lymph node dissection.

METHODS

A prospective analysis was performed on the clinical data of 307 patients with advanced gastric cancer who underwent laparoscopic surgery in the General Surgery Department of Weifang People’s Hospital between June 2018 and February 2021. The patients were randomly divided into experimental group and control group based on whether they received preoperative nanocarbon injection or not. The experimental group was divided into different groups according to the preoperative labeling time. The number of dissected lymph nodes and the number of lymph nodes with black staining were compared in each group after surgery, and the role of nanocarbon in the number of dissected lymph nodes, pathological staging, and the relationship with prognosis were discussed.

RESULTS

The average number of dissected lymph nodes in the experimental group was higher than that in the control group. In the experimental group, the number of lymph node dissections and number of black-staining lymph nodes in the nanocarbon-labeling group at 2 d and 1 d before surgery were higher than in the labeling group on the day before surgery (P < 0.05).

CONCLUSION

Preoperative nanocarbon labeling can safely and effectively guide lymph node dissection. To improve the detection rate of lymph nodes is conducive to subsequent comprehensive anti-tumor therapy.

Long-term survival of patients with stage II and III gastric cancer who underwent gastrectomy with inadequate nodal assessment

BACKGROUND

Gastric cancer is an aggressive disease with frequent lymph node (LN) involvement. The NCCN recommends a D2 lymphadenectomy and the harvesting of at least 16 LNs. This threshold has been the subject of great debate, not only for the extent of surgery but also for more appropriate staging. The reclassification of stage IIB through IIIC based on N3b nodal staging in the eighth edition of the American Joint Committee on Cancer (AJCC) staging system highlights the efforts to more accurately discriminate survival expectancy based on nodal number. Furthermore, studies have suggested that pathologic assessment of 30 or more LNs improve prognostic accuracy and is required for proper staging of gastric cancer.

AIM

To evaluate the long-term survival of advanced gastric cancer patients who deviated from expected survival curves because of inadequate nodal evaluation.

METHODS

Eligible patients were identified from the Surveillance, Epidemiology, and End Results database. Those with stage II–III gastric cancer were considered for inclusion. Three groups were compared based on the number of analyzed LNs. They were inadequate LN assessment (ILA, < 16 LNs), adequate LN assessment (ALA, 16-29 LNs), and optimal LN assessment (OLA, ≥ 30 LNs). The main outcomes were overall survival (OS) and cancer-specific survival. Data were analyzed by the Kaplan-Meier product-limit method, log-rank test, hazard risk, and Cox proportional univariate and multivariate models. Propensity score matching (PSM) was used to compare the ALA and OLA groups.

RESULTS

The analysis included 11607 patients. Most had advanced T stages (T3 = 48%; T4 = 42%). The pathological AJCC stage distribution was IIA = 22%, IIB = 18%, IIIA = 26%, IIIB = 22%, and IIIC = 12%. The overall sample divided by the study objective included ILA (50%), ALA (35%), and OLA (15%). Median OS was 24 mo for the ILA group, 29 mo for the ALA group, and 34 mo for the OLA group (P < 0.001). Univariate analysis showed that the ALA and OLA groups had better OS than the ILA group [ALA hazard ratio (HR) = 0.84, 95% confidence interval (CI): 0.79–0.88, P < 0.001 and OLA HR = 0.73, 95%CI: 0.68–0.79, P < 0.001]. The OS outcome was confirmed by multivariate analysis (ALA HR = 0.68, 95%CI: 0.64–0.71, P < 0.001 and OLA: HR = 0.48, 95%CI: 0.44–0.52, P < 0.001). A 1:1 PSM analysis in 3428 patients found that the OLA group had better survival than the ALA group (OS: OLA median = 34 mo vs ALA median = 26 mo, P < 0.001, which was confirmed by univariate analysis (HR = 0.81, 95%CI: 0.75–0.89, P < 0.001) and multivariate analysis: (HR = 0.71, 95%CI: 0.65–0.78, P < 0.001).

CONCLUSION

Proper nodal staging is a critical issue in gastric cancer. Assessment of an inadequate number of LNs places patients at high risk of adverse long-term survival outcomes.

Neoadjuvant versus Postoperative Chemoradiotherapy is Associated with Improved Survival for Patients with Resectable Gastric and Gastroesophageal Cancer

BACKGROUND

The optimal timing of chemoradiotherapy (CRT) for patients with localized gastric cancer remains unclear. This study aimed to compare the survival outcomes between neoadjuvant and postoperative CRT for patients with gastric and gastroesophageal junction (GEJ) cancer.

METHODS

This retrospective study analyzed 152 patients with gastric (42%) or GEJ (58%) adenocarcinoma who underwent definitive surgical resection and received either neoadjuvant or postoperative CRT between 2005 and 2017 at the authors' institution. The primary end point of the study was overall survival (OS).

RESULTS

The median follow-up period was 37.5 months. Neoadjuvant CRT was performed for 102 patients (67%) and postoperative CRT for 50 patients (33%). The patients who received neoadjuvant CRT were more likely to be male and to have a GEJ tumor, positive lymph nodes, and a higher clinical stage. The median radiotherapy (RT) dose was 50.4 Gy for neoadjuvant RT and 45.0 Gy for postoperative RT (p < 0.001). The neoadjuvant CRT group had a pathologic complete response (pCR) rate of 26% and a greater rate of R0 resection than the postoperative CRT group (95% vs. 76%; p = 0.002). Neoadjuvant versus postoperative CRT was associated with a lower rate of any grade 3+ toxicity (10% vs. 54%; p < 0.001). The multivariable analysis of OS showed lower hazards of death to be independently associated neoadjuvant versus postoperative CRT (hazard ratio [HR] 0.57; 95% confidence interval [CI] 0.36-0.91; p = 0.020) and R0 resection (HR 0.50; 95% CI 0.27-0.90; p = 0.021).

CONCLUSIONS

Neoadjuvant CRT was associated with a longer OS, a higher rate of R0 resection, and a lower treatment-related toxicity than postoperative CRT. The findings suggest that neoadjuvant CRT is superior to postoperative CRT in the treatment of gastric and GEJ cancer.

Surgical Treatment for Gastric Cancer

Surgery is an essential component of curative-intent treatment strategies for gastric cancer. However, the care of each patient with gastric cancer must be individualized based on patient and tumor characteristics. It is important that all physicians who will be caring for patient with gastric cancer understand the current best practices of surgical management to provide patients with the highest quality of care. This article aims to provide this information while acknowledging areas of surgical management that are still controversial.

Surgical Management of Gastric Cancer: A Systematic Review

Gastric cancer is the fifth most common cancer worldwide, and it is responsible for 7.7% of all cancer deaths. Despite advances in the field of oncology, where radiotherapy, neo and adjuvant chemotherapy may improve the outcome, the only treatment with curative intent is represented by surgery as part of a multimodal therapy. Two concepts may be adopted in appropriate cases, neoadjuvant treatment before gastrectomy (G) or primary surgical resection followed by chemotherapy. Such an approach, combined with early detection and better screening, has led to a decrease in the overall incidence of gastric cancer. Unfortunately, malignant tumors of the stomach are often diagnosed in locally advanced or metastatic stages when the median overall survival remains poor. Surgical care in these cases must be provided by a multidisciplinary team in a high-volume center. Important surgical aspects such as optimum resection margins, surgical technique, and number of harvested lymph nodes are important factors for patient outcomes. The standardization of surgical treatment of gastric cancer in accordance with the patient’s profile is of decisive importance for a better outcome. This review aims to summarize the current standards in the surgical treatment of gastric cancer.

A greater lymph node yield is required during pathological examination in microsatellite instability-high gastric cancer

Background

The impact of microsatellite status on lymph node (LN) yield during lymphadenectomy and pathological examination has never been assessed in gastric cancer (GC). In this study, we aimed to appraise the association between microsatellite instability-high (MSI-H) and LN yield after curative gastrectomy.

Methods

We retrospectively analyzed 1757 patients with GC undergoing curative gastrectomy and divided them into two groups: MSI-H (n = 185(10.5%)) and microsatellite stability (MSS) (n = 1572(89.5%)), using a five-Bethesda-marker (NR-24, BAT-25, BAT-26, CAT-25, MONO-27) panel. The median LN count and the percentage of specimens with a minimum of 16 LNs (adequate LN ratio) were compared between the two groups. The log odds (LODDS) of positive LN count (PLNC) to negative LN count (NLNC) and the target LN examined threshold (TLNT_(x%)) were calculated in both groups.

Results

Statistically significant differences were found in the median LN count between MSI-H and MSS groups for the complete cohort (30 vs. 28, p = 0.031), for patients undergoing distal gastrectomy (DG) (30 vs. 27, p = 0.002), for stage II patients undergoing DG (34 vs. 28, p = 0.005), and for LN-negative patients undergoing DG (28 vs. 24, p = 0.002). MSI-H was an independent factor for higher total LN count in patients undergoing DG (p = 0.011), but it was not statistically correlated to the adequate LN ratio. Statistically significant differences in PLNC, NLNC and LODDS were found between MSI-H GC and MSS GC (all p < 0.001). The TLNT_(90%) for MSI-H and MSS groups were 31 and 25, respectively. TLNT_(X%) of MSI-H GC was always higher than that of MSS GC regardless of the given value of X%.

Conclusions

MSI-H was associated with higher LN yield in patients undergoing gastrectomy for GC. Although MSI-H did not affect the adequacy of LN harvest, we speculate that a greater lymph node yield is required during pathological examination in MSI-H GC.

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

BACKGROUND

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Variation in Adequate Lymph Node Yield for Gastric, Lung, and Bladder Cancer: Attributable to the Surgeon, Pathologist, or Hospital?

BACKGROUND

The Commission on Cancer recently released quality-of-care measures regarding adequate lymphadenectomy for colon, gastric, lung, and bladder cancer. There is currently little information regarding variation in adequate lymph node yield (ALNY) for gastric, lung, and bladder cancer.

METHODS

The New York State Cancer Registry and Statewide Planning and Research Cooperative System were queried for stage I-III gastric, stage I-II lung, and stage II-III bladder cancer resections from 2004 to 2014. Hierarchical models assessed factors associated with ALNY (gastric ≥ 15; lung ≥ 10; bladder ≥ 2). Additionally, the proportions of variation attributable to surgeons, pathologists, and hospitals were estimated among Medicare patients.

RESULTS

Among 3716 gastric, 18,328 lung, and 1512 bladder cancer resections, there were low rates of ALNY (gastric = 53%, lung = 36%, bladder = 67%). When comparing 2004-2006 and 2012-2014, there was significant improvement in ALNY for gastric cancer (39% vs. 68%), but more modest improvement for lung (33% vs. 38%) and bladder (65% vs. 71%) cancer. Large provider-level variation existed for each organ system. After controlling for patient-level factors/variation, the majority of variation was attributable to hospitals (gastric: surgeon = 4%, pathologist = 2.8%, hospital = 40%; lung: surgeon = 13.8%, pathologist = 1.5%, hospital = 18.3%) for gastric and lung cancer. For bladder cancer, most of the variation was attributable to pathologists (surgeon = 3.3%, pathologist = 10.5%, hospital = 6.2%).

CONCLUSIONS

ALNY rates are low for gastric, lung, and bladder cancer, with only modest improvement over time for lung and bladder cancer. Given that the proportion of variation attributable to the surgeon, pathologist, and hospital is different for each organ system, future quality improvement initiatives should target the underlying causes, which vary by individual organ system.

Gastrectomy case volume and textbook outcome: an analysis of the Population Registry of Esophageal and Stomach Tumours of Ontario (PRESTO)

OBJECTIVE

To determine the association between gastric cancer surgery case-volume and Textbook Outcome, a new composite quality measurement.

BACKGROUND

Textbook Outcome included (a) negative resection margin, (b) greater than 15 lymph nodes sampled, (c) no severe complication, (d) no re-intervention, (e) no unplanned ICU admission, (f) length of stay of 21 days or less, (g) no 30-day readmission and (h) no 30-day mortality following surgery.

METHODS

All patients undergoing gastrectomy for non-metastatic gastric adenocarcinoma registered in the Population Registry of Esophageal and Stomach Tumours of Ontario between 2004 and 2015 were included. We used multivariable generalized estimating equation (GEE) logistic regression modelling to estimate the association between gastrectomy volume (surgeon and hospital annual volumes) and Textbook Outcome. Volumes were considered as continuous variables and quintiles.

RESULTS

Textbook Outcome was achieved in 378 of 1660 patients (22.8%). The quality metrics least often achieved were inadequate lymph node sampling and presence of severe complications, which occurred in 46.1% and 31.7% of patients, respectively. Accounting for covariates and clustering, neither surgeon volume nor hospital volume were significantly associated with Textbook Outcome. However, hospital volume was associated with adequate lymphadenectomy and fewer unplanned ICU admissions.

CONCLUSIONS

Higher case volume can impact certain measures of quality of care but may not address all care structures necessary for ideal Textbook recovery. Future quality improvement strategies should consider using case-mix adjusted Textbook Outcome rates as a surgical quality metric.

Intraoperative Surrogate Indicators of Gastric Cancer Patients' Long-Term Prognosis: The Number of Lymph Nodes Examined Relates to the Lymph Node Noncompliance Rate

BACKGROUND

The number of examined lymph nodes (ExLNs) and the rate of lymph node (LN) noncompliance are two independent indicators for evaluating the oncological efficacy for radical gastric cancer (GC) surgery. There are no studies to prove the relationship between these two indicators and their influence on the long-term prognosis of GC patients.

METHODS

The clinicopathological data of 1872 patients with radical GC resection with pathological stage pT2-4N0-3M0 from June 2007 to June 2013 were retrospectively analyzed. Noncompliance was defined as patients with more than one or more LN stations absence as described in the protocol for lymphadenectomy in the Japanese Gastric Cancer Association.

RESULTS

Among 1872 patients, 941 (50.3%) had complete LN compliance, 469 (25.1%) had minor LN noncompliance, and 462 (24.6%) had major LN noncompliance. Logistic regression analysis showed that cT staging and ExLNs were independent risk factors for LN noncompliance. In the whole group, Kaplan-Meier survival curve elucidated that overall survival (OS) differences of ExLNs ≤ 25 and ExLNs > 25 were statistically significant (p < 0.001). Stratified analysis of LN noncompliance elucidated no statistically significant difference in OS of these two group. Multivariate COX regression analysis suggested that LN noncompliance was an independent prognostic factor for OS, whereas ExLNs was no longer an independent prognostic factor for OS.

CONCLUSIONS

The increase number of ExLNs can improve the OS of GC patients, which depends on the decrease of LN noncompliance rate. As surrogate indicators for long-term prognosis of GC patients, LN noncompliance rate was better than ExLNs number.

Evaluating Dissemination of Adequate Lymphadenectomy for Gastric Cancer in the USA

BACKGROUND

Adequate lymphadenectomy (AL) of 15+ lymph nodes comprises an important component of gastric cancer surgical therapy. Despite endorsement by the National Comprehensive Cancer Network and the Committee on Cancer, initial adoption of this paradigm has been relatively slow. The current analysis sought to perform an adjusted time-trend evaluation of the factors associated with AL and its dissemination.

METHODS

Utilizing the 2004-2015 National Cancer Database, 28,985 patients were identified who underwent gastrectomy for adenocarcinoma. An adjusted time-trend analysis was performed to estimate the adoption of AL overall. Multivariable logistic regression was utilized to assess factors associated with these observed trends. Interactions and stratified models determined disparate effects in vulnerable populations (older adults, ethnic minorities, low socioeconomic status).

RESULTS

The adjusted time-trend analysis demonstrated an overall 30% increase (28.8 to 58.7%) in receipt of AL (OR 1.10 increase/year; 95%CI 1.09-1.10) from 2004 to 2015. This trend persisted even after stratifying the models by age, race/ethnicity, and income (OR 1.07-1.12; p < 0.05). Slowest rates of adoption were seen amongst hospitals in the Midwest census region (OR 1.08, CI 1.06-1.90) and comprehensive community hospitals (OR 1.08, CI 1.06-1.91) and with African-American patients (OR 1.09, CI 1.06-1.11) (all p < 0.05).

CONCLUSION

This multi-center evaluation demonstrates increased adoption of AL during gastric cancer surgery in the USA overall and amongst vulnerable populations, although regional and racial disparities were observed. Future studies are needed to investigate reasons underlying racial and regional differences in receipt of AL.

Insufficient lymph node assessment in gastric adenocarcinoma

BACKGROUND

This study aimed to investigate the sufficient (≥ 16) lymph node assessment in 449 patients with gastric adenocarcinoma and literature review.

METHODS

Four hundred and forty-nine patients with pathologically confirmed locoregional invasive gastric adenocarcinoma from 2004 to 2013 were included. A standard surgical resection was performed for all the patients with (n = 16) or without (n = 433) neoadjuvant treatment.

RESULTS

In this study, 301 men and 148 women with a median age of 58 (range 21-88) years were included. The median total numbers of examined lymph nodes were 9 (range 0-55). Ninety-five patients (21.2%) had adequate (≥ 16) lymph node examination, and 70 patients (15.6%) had no examined lymph nodes. In univariate analysis, total or near total gastrectomy (P <  0.001), advanced node stage (P < 0.001), primary tumor size > 6 cm (P < 0.001), and the presence of perineural invasion (P = 0.039) were associated with more average number of examined lymph nodes. On multivariate analysis, node stage (P < 0.001) and type of surgery (P = 0.008) were independent predictive factors.

CONCLUSION

In this study, approximately one in five patients with gastric adenocarcinoma had sufficient lymph node assessment. More studies are suggested for identifying a true inadequate lymph node dissection from insufficient lymph node assessment.

Prognostic analysis of stage III gastric cancer after curative surgery according to the newest TNM classification

AIM

To study the prognostic factors of gastric cancer (GC) patients who were classified with stage III disease according to the newest TNM classification.

METHODS

This study retrospectively enrolled 279 patients who underwent radical gastrectomy from January 2012 to December 2014 at our hospital and who were diagnosed with stage III GC according to the new 8th edition of the TNM classification. The patient data that were collected included age, sex, pathological parameters, survival, lymph node ratio, neo-adjuvant chemotherapy with oxaliplatin and S-1, and operation type. The characteristics, survival, and prognostic factors of the patients were analyzed by univariate and multivariate analyses.

RESULTS

The median OS of the patients after curative surgery was 19 months, and the 3-year survival rate (3-YSR) was 25.3%. A univariate analysis showed that tumor location (P = 0.01), neo-adjuvant chemotherapy (P = 0.005), pathological T stage (P = 0.002), pathological N stage (P < 0.001), lymph node ratio (LNR) (P < 0.001), and operation type (P = 0.032) were significantly associated with overall survival. A multivariate analysis revealed that neo-adjuvant chemotherapy (P = 0.009), pathological T stage (P = 0.012), and LNR (P < 0.001) were independent prognostic factors.

CONCLUSIONS

Neo-adjuvant chemotherapy, pathological T stage, and LNR were independent prognostic factors for the overall survival of patients with stage III GC. The neo-adjuvant chemotherapy with oxaliplatin and S-1 can be used for the patients to improve their survival.

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.

A Nomogram for Predicting Overall Survival of Gastric Cancer Patients with Insufficient Lymph Nodes Examined

Insufficient number of examined lymph nodes (eLNs) was considered to increase significantly the risk of stage migration in gastric cancer patients. The aim of our study is to establish a nomogram predicting the overall survival (OS) for patients with an insufficient number of eLNs. A total of 872 gastric cancer patients with extended lymphadenectomies were assigned randomly (2:1) to the development cohort and the validation cohort. The nomogram was established based on the Cox regression model using the development cohort. The concordance index (C-index) was used to evaluate the discriminative ability. We also compared our model with two other staging systems. Using multivariate analysis, age, sex, tumor location, depth of invasion, macroscopic type, lymphovascular invasion, the number of eLNs, and metastatic lymph nodes were selected and incorporated into the nomogram. The C-index of the nomogram was 0.742 and 0.743 in development and validation cohorts, respectively, which were significantly superior to the C-indices (range 0.705-0.712, all P < 0.001) of American Joint Committee on Cancer (AJCC) seventh edition and lymph node ratio staging systems in both cohorts. We established a nomogram which could predict accurately OS for gastric cancer patients with insufficient number of eLNs.

N staging: the role of the pathologist

Gastric cancer is the second cause of cancer-related mortality worldwide. Metastases, including lymph nodes ones, heavily influence the prognosis of this disease. The pathological detection of positive lymph nodes is pivotal for an optimal prognostication and clinical management of affected individuals. Several factors influence the pathological investigation of surgical specimens, ultimately affecting the number of retrieved lymph nodes and, with it, the reliability of N staging. The pathologist plays a central role in optimizing this process. Factors influencing lymph node retrieval and analysis will be herein reviewed, together with the procedures adopted for an optimal pathological analysis of lymph nodes in gastric cancer.

Prognostic impact of the number of retrieved lymph nodes in patients with gastric cancer

BACKGROUND

In gastric cancer, although at least 16 lymph nodes of retrieved lymph nodes (RLNs) are recommended for nodal staging in Japanese Classification of Gastric Carcinoma and TNM classifications, we wished to clarify their appropriateness.

STUDY DESIGN

A total of 1289 consecutive gastric cancer patients, who underwent gastrectomy between 1997 and 2011, were analyzed retrospectively.

RESULTS

(i) The patients were divided into two groups using a cut-off RLN number of 16 (RLN < 16 or RLN ≥ 16). There were significant differences in the survival rates of patients in pStage II (P < 0.0001) and III (P = 0.0009), but not those of patients in pStage I (P = 0.0627) and IV (P = 0.1553). (ii) In 498 consecutive patients in pStage II and III, compared with patients in the RLN ≥ 16 group, those in the RLN < 16 group had a significantly higher incidence of older age (P = 0.0004) and positive lymph node ratio (PLNR) (P < 0.0001). Univariate and multivariate analyses showed that an RLN number of less than 16 was an independent poor prognostic factor (P < 0.0001, HR 2.48 [95% CI: 1.60-3.70]). (iii) A cut-off RLN number of 16 could cause the stage migration effect in pStage II or III patients. A cut-off RLN number of 25 or more could eliminate the prognostic effect.

CONCLUSION

The RLN number may potentially affect the prognosis and the stage migration in pStage II or III gastric cancer patients. An RLN number of 25 or more could be sufficient for nodal staging.

Lymph node retrieval and examination during the implementation of extended lymph node dissection for gastric cancer in a non-specialized western institution

The optimal degree of lymph node dissection for gastric cancer is still matter of debate. Particularly, there are serious doubts about the reproducibility of extended lymph node dissection in western surgical units, and no studies to date have investigated factors influencing lymph node retrieval and examination during the learning curve. Univariate and multivariate retrospective analysis of 21 variables were carried out on a prospective series of 313 consecutive resections for gastric cancer performed by ten different surgeons, with lymph node retrieval and analysis performed by ten different pathologists. Endpoints were number of examined lymph nodes per patient, number of cases with inadequate nodal staging (<15 examined lymph nodes) and lymph node ratio (calculated as the absolute ratio between the number of metastatic and the number of examined lymph nodes). The number of examined lymph nodes per patient (mean ± SD 28.3 ± 14.1, median 26, range 2-78) was independently influenced by age, pN status, the type of gastric resection, the degree of lymph node dissection and single pathologist. There were 47 cases (15.0%) with incomplete nodal staging that was independently determined by the degree of lymph node dissection and by the pathologist. Lymph node ratio was independently influenced by the number of metastatic lymph nodes, the disease stage and by the histological subtype of the tumor. The role of an experienced or dedicated pathologist should not be underevaluated in western series when dealing with lymph node retrieval and examination. Lymph node ratio appeared not to be significantly influenced by the number of examined lymph nodes, being independently influenced only by the number of metastatic lymph nodes, the disease stage and by the histological subtype of the tumor. It could be therefore tested as a prognostic factor limiting the stage-migration phenomenon induced by extended lymph node dissection.

Patients with Adenocarcinoma of the Small Intestine with 9 or More Regional Lymph Nodes Retrieved Have a Higher Rate of Positive Lymph Nodes and Improved Survival

PURPOSE

To assess the influence of regional lymph node (RLN) retrieval on stage migration of adenocarcinoma of the small intestine and survival.

PATIENTS AND METHODS

From the Surveillance, Epidemiology, and End Results database,1090 patients with nonmetastatic small bowel adenocarcinoma were identified in between 2004 and 2011. The impact of the number of RLNs removed on histopathological staging and oncological outcome was assessed utilizing Cox proportional hazard regression models with and without risk-adjustment, propensity score methods, and joinpoint regression analysis.

RESULTS

The rate of node-positive cancer increased steadily with the number of retrieved RLNs up to 9 RLNs, which suggests that a minimum of 9 (95 % CI 5.5–10.5) retrieved RLNs are needed for the detection of node-positive disease (P < 0.001). From 657 of 1090 patients (60.3 %), 9 or more RLNs were retrieved. While in 2004 only in 46.0 % of all cases 9+ RLNs were retrieved, this rate increased to 69.3 % in 2011 (P < 0.001). The multivariable analysis demonstrated that the retrieval of 9+ RLNs was associated with better overall (hazard ratio of death [HR] = 0.67, 95 % CI 0.55–0.82, P < 0.001) and cancer-specific survival (HR = 0.77, 95 % CI 0.61–0.96, P = 0.022). This finding was confirmed by a propensity score-adjusted analysis, which indicated increased overall (HR = 0.67, 95 % CI 0.50–0.89, P < 0.001) and cancer-specific survival (HR = 0.67, 95 % CI 0.49–0.92, P = 0.013) in patients with the retrieval of 9+ RLNs.

CONCLUSION

To our knowledge, this is the first population-based propensity score-adjusted investigation in small bowel adenocarcinoma. A sufficient number of RLNs should be retrieved to achieve an optimal oncological outcome

Importance of Adequate Lymphadenectomy in Gastrointestinal Cancer

One of the most important factors influencing cancer-specific survival in the field GI oncology is the presence of positive lymph nodes. Although it remains controversial, adequate lymph node examination is required for accurate staging such that patients can receive correct adjuvant treatments and for stratification in clinical trials. Nevertheless, wide variation in the quality of lymph node examination exists in the US and many centers are not meeting guideline treatment recommendations.

Minimally invasive gastrectomy for gastric adenocarcinoma in the United States: Utilization and short-term oncologic outcomes

BACKGROUND AND OBJECTIVES

When performed at select centers, minimally invasive gastrectomy (MIG) for gastric adenocarcinoma is associated with reduced perioperative morbidity, and similar oncologic outcomes as compared to open gastrectomy (OG). Utilization of, and outcomes associated with, MIG in the United States have not been characterized.

METHODS

The National Cancer Database (2010-2011) was queried for AJCC pStage IB-IIIC patients who underwent curative-intent OG (n = 2,303) or MIG (n = 331). Multivariable models identified factors associated with MIG utilization, R0 resection rates, and adequate lymph node staging (LNS).

RESULTS

MIG was more frequently utilized for T1/T2 (P < 0.001), N0 (P = 0.022), and stage IB (P = 0.001) tumors. MIG was associated with shorter hospital stay (P < 0.001), equivalent lymph node examination (P = 0.337) and superior rates of R0 resection (P = 0.011) compared with OG. In patients undergoing MIG, R0 resection was associated with performance of near-total/total gastrectomy (OR 3.90, 95%CI 1.10-13.9) and tumors < 5 cm (OR 2.78, 95%CI 1.07-7.26). Adequate LNS was associated with surgery at academic (OR 1.99, 95%CI 1.19-3.32) or high-volume facilities (OR 2.97, 95%CI 1.59-5.54), tumor size ≥ 5 cm (OR 1.85, 95%CI 1.10-3.11), and node positivity (OR 1.75, 95%CI 1.04-2.93).

CONCLUSIONS

MIG is selectively utilized in cases with favorable tumor characteristics. In such cases, short-term oncologic outcomes are equivalent to those achieved with OG. Worse oncologic outcomes in specific subgroups underscore opportunities for quality improvement.

Metastatic lymph node ratio successfully predicts prognosis in western gastric cancer patients

BACKGROUND

Lymph node positivity is a strong prognostic indicator in many cancers including gastric cancer. The extent of surgical resection directly influences the number of lymph nodes available for staging, with the lesser D1 resection that is standard practice in non-Asian countries typically providing fewer nodes for analysis. The widely used AJCC TNM staging system has been criticized for under-staging and stage migration where fewer than 15 nodes are resected, which is often the case in these populations. The ratio of positive to total nodes harvested--Lymph Node Ration (LNR)--has been proposed as an improved and more widely applicable prognostic indicator.

HYPOTHESIS

The LNR is a reliable and accurate prognostic indicator of survival in a Western gastric cancer population.

METHODS

9357 patients were acquired via a SEER case listing session with 2004-2011 gastric adenocarcinoma diagnoses. AJCC 7th edition nodal staging (N0: 0, N1:1-2, N2:3-6, N3:≥7 positive lymph nodes) and LNR positive nodal staging (PN0: 0%, PN1: 1-20%, PN2: 21-50%, PN3: 51-100% of examined nodes positive) were compared as respects seven year survivorship.

RESULTS

Adjusted survival time ratios for AJCC nodal curves were less evenly distributed than were the percent positive nodal curves. Results of multiple regression reflected that survival time ratios of the percent positive nodal schema being more evenly spaced than those of the AJCC schema. Because BIC for AJCC, 41071.48, was larger than that for percent positive nodes, 41024.25, the LNR nodal system better explained survival than the AJCC nodal classification system.

CONCLUSION

LNR produced reliable and internally consistent survival curves for this population. LNR is an effective tool to predict survival in a western gastric cancer patient population, where the majority of the patients have limited lymph node dissection.

Validating the prognostic and discriminating value of the TNM-classification for gastric cancer - a critical appraisal

AIM

We investigated the effect of the new tumour-, node-, metastasis- (TNM) classification on predicting and discriminating gastric cancer patient prognosis using the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program.

PATIENTS AND METHODS

From the SEER-database we retrieved gastric cancer patients with a primary adenocarcinoma, of Caucasian or Asian ethnicity and without distant metastases (M0). The pTNM-stage was determined according to the 7th edition of the union internationale contre le cancer (UICC) guidelines.

RESULTS

Spanning the period 2004-2010, 6136 patients fulfilled all inclusion criteria including 3424 (55.8%) men, 2712 (44.2%) women, 4629 (75.4%) Caucasian and 1507 (24.6%) Asian patients. 1524 (24.8%) patients underwent total gastrectomy and 4612 (75.2%) non-total gastrectomy. Only in 41.2% of the patients were >15 lymph nodes resected. 1857 (31.0%) patients received radiotherapy. Patient survival depended on ethnicity, type of surgery and radiotherapy. The discriminating value of the UICC-stage grouping could not be validated for Caucasian patients with >15 lymph nodes resected and who had not received radiotherapy: stage groups IIB, IIIA, IIIB and IIIC showed substantial overlap in survival ranges. In addition, the tumour specific survival of the different T-/N-combinations was significantly different in stage groups IIIB and IIIC, respectively.

CONCLUSIONS

Our retrospective analysis of the SEER-database does not validate the discriminating value of stage grouping of the 7th edition of the UICC-stage grouping. A revision should be considered and more reliable prognostic biomarkers are urgently needed.

Is retrieval of at least 15 lymph nodes sufficient recommendation in early gastric cancer?

Purpose

The evaluation and extent of lymph node (LN) retrieval is clinically relevant for staging because lymphatic invasion is the most common mechanism leading to up-staging of carcinoma. However, the optimal number of LN retrievals for early gastric cancer (EGC) is unclear. With the aim of clarification, we analyzed our database to investigate the optimal number of retrieved LNs in EGC.

Methods

Three hundred twenty-six gastric cancer patients who underwent curative gastrectomy with D2 LN dissection at Ewha Womans University Hospital (Dongdaemun and Mokdong) were analyzed according to sex, age, tumor location, size of tumor, macroscopic type, histological classification, depth of invasion, LNs metastasis, TNM stage and type of surgery.

Results

In LN negative cases, patients with 15-25 retrieved LNs had a 5- and 10-year survival rate of 88% and 54%, respectively, whereas retrieval of ≥26 LNs was associated with 5- and 10-year survival rate of 90% and 75%, respectively (P = 0.105). In LN positive cases, the 5- and 10-year survival rate was 50% and 30% for the 15-25 group, and 77% and 67% for the ≥26 group, respectively (P = 0.044).

Conclusion

LN metastasis is an independent factor of survival and the number of retrieved LNs significantly relate to the long-term survival benefit in node metastatic EGC. Also, our data suggest that the retrieval of at least 15 LNs may not be sufficient to warrant recommendation for more curative surgery, and that qualified LN dissection should be considered if LN metastasis is in doubt, even in EGC.

Does the retrieval of at least 15 lymph nodes confer an improved survival in patients with advanced gastric cancer?

PURPOSE

The standard surgical procedure recommended to treat gastric cancer in advanced cases is dissection of D2 lymph nodes (LNs). However, the optimum number of LNs that should be retrieved in advanced gastric cancer (AGC) remains debatable. Therefore, this study aimed to investigate the optimum number of retrieved LNs and determine the clinical implications of retrieved LN numbers on the treatment of AGC.

MATERIALS AND METHODS

Of 575 AGC patients reviewed, 369 who underwent open curative gastrectomy with D2 or more extensive LN dissection at our institution were analyzed according to their clinicopathologic characteristics and number of LNs retrieved.

RESULTS

Multivariate regression analysis revealed that tumor size (P=0.006), depth of invasion (P=0.000), LN metastasis (P=0.000), and stage (P=0.000) were independent variables with predictive value. The 5-year survival rates were differed significantly according to the numbers of LNs retrieved ([1] 15~25 vs. >25 and [2] 15~39 vs. ≥40) in patients with differentiated carcinoma.

CONCLUSIONS

Tumor size, depth of invasion, LN metastasis, and stage were independent predictive factors for survival. The number of retrieved LNs was significantly associated with a long-term survival benefit in patients with differentiated carcinoma. Therefore, our data suggest that the retrieval of a minimum of 15 LNs may not be sufficient to warrant a recommendation for further curative surgery and that extensive LN dissection should be considered in advanced carcinoma of the differentiated type.

Implications of inadequate lymph node staging in resectable gastric cancer: a contemporary analysis using the National Cancer Data Base

BACKGROUND

National guidelines recommend examination of ≥ 15 lymph nodes for adequate staging of resectable gastric adenocarcinoma (GA). The relevance of these guidelines, which were established before the increasing use of multimodality therapy, and the impact of inadequate lymph node staging (LNS) in a contemporary cohort have not been extensively explored.

METHODS

Stage I-III GA patients who underwent gastrectomy from 1998 to 2011 were identified using the National Cancer Data Base. Trends in LNS adequacy, predictors of inadequate LNS (< 15 LN examined) and the relationship between LNS and overall survival (OS) were analyzed.

RESULTS

In 22,409 patients, compliance with LNS guidelines was poor (inadequate LNS in 61.2% of cases, median LN harvested in 11.0%). Subtotal/partial gastrectomy was the strongest predictor of inadequate LNS (OR = 2.01, P < .001). Survival analyses included 9139 patients with minimum 5 years follow-up; median, 1-year, and 5-year survival was 35.6 months, 75.5%, and 39.7%, respectively. LN positivity (HR = 1.90) and age > 76 years (HR = 1.73) were the strongest predictors of worse OS (both P < .001). Inadequate LNS was independently associated with worse OS (HR = 1.33, P < .001). Median OS after inadequate compared to adequate LNS was significantly worse (33.3 months versus 42.0 months, P < .001), regardless of AJCC clinical stage subgroup or tumor T classification (both P < .001).

CONCLUSIONS

Adequate LNS is achieved in a minority of patients. Inadequate LNS was independently associated with worse OS. Examination of ≥ 15 LN is a reproducible prognosticator of gastric cancer outcomes in the United States and should continue to serve as a benchmark for quality of care.

A comparative study on two different pathological methods to retrieve lymph nodes following gastrectomy

BACKGROUND

The number of lymph nodes harvested during gastrectomy depends on the extension of lymphadenectomy and the method of lymph node retrieval.

AIM

The objective of this study was to evaluate two methods of lymph node retrieval in specimens of gastric cancer.

METHODS

The number of lymph nodes was compared using two different techniques. The technique used in the first group was manual dissection following formalin fixation, and the techniques used in the second group was fat-clearing by acetone.

RESULTS

Both groups were comparable for demographic and pathological variables. The average number of harvested nodes was 19.3 ± 10 for the manual group as compared to 26.1 ± 14 in the acetone group (P = 0.003). The differences in the average number of positive nodes did not reach statistical significance (4.6 compared to 6.9 nodes).

CONCLUSION

The acetone clearing technique enables the evaluation of a larger number of nodes. An increase, but statistically non significant, number of positive nodes was noted in the acetone group.

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

Objective. The study was designed to explore the prognostic value of examined lymph node (LN) number on survival of gastric cancer patients without LN metastasis. Methods. Between August 1995 and January 2011, 300 patients who underwent gastrectomy with D2 lymphadenectomy for LN-negative gastric cancer were reviewed. Patients were assigned to various groups according to LN dissection number or tumor invasion depth. Some clinical outcomes, such as overall survival, operation time, length of stay, and postoperative complications, were compared among all groups. Results. The overall survival time of LN-negative GC patients was 50.2 ± 30.5 months. Multivariate analysis indicated that LN dissection number (P < 0.001) and tumor invasion depth (P < 0.001) were independent prognostic factors of survival. The number of examined LNs was positively correlated with survival time (P < 0.05) in patients with same tumor invasion depth but not correlated with T1 stage or examined LNs >30. Besides, it was not correlated with operation time, transfusion volume, length of postoperative stay, or postoperative complication incidence (P > 0.05). Conclusions. The number of examined lymph nodes is an independent prognostic factor of survival for patients with lymph node-negative gastric cancer. Sufficient dissection of lymph nodes is recommended during surgery for such population.

Prognostic value of number of examined lymph nodes in patients with node-negative gastric cancer

AIM: To elucidate the potential impact of examined lymph nodes (eLNs) on long-term survival of node-negative gastric cancer patients after curative surgery.

METHODS: A total of 497 node-negative gastric cancer patients who underwent curative gastrectomy between January 2000 and December 2008 in our center were enrolled in this study. Patients were divided into 4 groups according to eLNs through cut-point analysis. Clinicopathological features were compared between ≤ 15 eLNs group and > 15 eLNs group and potential prognostic factors were analyzed. The Log-rank test was used to assess statistical differences between the groups. Independent prognostic factors were identified using the Cox proportional hazards regression model. Stratified analysis was performed to investigate the impact of eLNs on patient survival in each stage. Overall survival was also compared among the four groups. Finally, we explored the recurrent sites associated with eLNs.

RESULTS: Patients with eLNs > 15 had a better survival compared with those with eLNs ≤ 15 for the entire cohort. By the multivariate survival analysis, we found that the depth of invasion and the number of eLNs were the independent predictors of overall survival (OS) of patients with node-negative gastric cancer. According to the cut-point analysis, T2-T4 patients with 11-15 eLNs had a significantly longer mean OS than those with 4-10 eLNs or 1-3 eLNs. Patients with ≤ 15 eLNs were more likely to experience locoregional and peritoneal recurrence than those with > 15eLNs.

CONCLUSION: Number of eLNs could predict the prognosis of node-negative gastric cancer, and dissection of > 15 eLNs is recommended during lymphadenectomy so as to improve the long-term survival.

Optimal management of gastric cancer: results from an international RAND/UCLA expert panel

OBJECTIVE

Defining processes of care, which are appropriate and necessary for management of gastric cancer (GC), is an important step toward improving outcomes.

METHODS

Using a RAND/UCLA Appropriateness Method, an international multidisciplinary expert panel created 22 statements reflecting optimal management. All statements were scored for appropriateness and necessity.

RESULTS

The following tenets were scored appropriate and necessary: (1) preoperative staging by computed tomography of abdomen/pelvis; (2) positron-emission tomographic scans not routinely indicated; (3) consideration for adjuvant therapy; (4) further clinical trials; (5) multidisciplinary decision making; (6) sufficient support at hospitals; (7) assessment of 16 or more lymph nodes (LNs); (8) in metastatic disease, surgery only for palliation of major symptoms; (9) surgeons experienced in GC management; (10) and surgeons experienced in both GC management and advanced laparoscopic surgery for laparoscopic resection. The following were scored appropriate, but of indeterminate necessity: (1) diagnostic laparoscopy before treatment; (2) a multidisciplinary approach to linitis plastica; (3) genetic assessment for diffuse GC and family history, or age less than 45 years; (4) endoscopic removal of select T1aN0 lesions; (5) D2 LN dissection in curative intent cases; (6) D1 LN dissection for early GC or patients with comorbidities; (7) frozen section analysis of margins; (8) nonemergent cases performed in a hospital with a volume of more than 15 resections per year; and (9) by a surgeon with more than 6 resection per year.

CONCLUSIONS

The expert panel has created 22 statements for the perioperative management of GC patients, to provide guidance to clinicians and improve the care received by patients.

The lymph node ratio as a prognostic factor for gastric cancer

To predict prognosis of gastric cancer, an adequate assessment of the stage of gastric cancer is important. The UICC/AJCC TNM classification is the most commonly used classification system. For adequate N staging at least 15 lymph nodes should be retrieved. In some countries, this amount of lymph nodes is not met, which can lead to understaging. Therefore, the lymph node ratio (LNR) is proposed as an alternative N staging modality. The purpose of this study was to compare the different staging modalities. Patients and methods. We included all patients who underwent surgery for gastric cancer, newly diagnosed between 2000 and 2009 and staged patient by UICC/AJCC TNM 5th/6th or 7th and by LNR. We conducted crude survival analysis, univariate and multivariate analyses according to the different staging systems. Results. The five-year overall survival rates ranged from 58% for N0 disease to 18% in case of more than 15 metastatic lymph nodes. The distribution of overall five-year survival according to LNR was 58% for LNR0 and 10% for LNR3. Univariate analysis showed that all the UICC/AJCC TNM classification systems as well as the LNR were strong prognostic factors for overall survival. The LNR correlated less with the number of nodes examined. Conclusion. LNR is a good prognostic tool for overall survival, it is an independent prognostic factor with a more homogenous spread of hazard ratios and five-year survival rates than UICC/AJCC systems. Furthermore, the LNR has a lower correlation with the number of nodes examined, making it less vulnerable for stage migration.

How many lymph nodes should be assessed in patients with gastric cancer? A systematic review

BACKGROUND

Nodal status is one of the most important prognostic factors in gastric adenocarcinoma (GC). As such, it is important to assess an appropriate number of lymph nodes (LNs) in order to accurately stage patients. However, the number of LNs assessed in each GC case varies, and in many cases the number examined per gastric specimen is less than current recommendations.

PURPOSE

We aimed to identify and synthesize findings from all articles evaluating the association of clinicopathological features and long-term outcomes with the number of LNs assessed among GC patients.

METHODS

Systematic electronic literature searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from 1998 to 2009.

RESULTS

Twenty-five articles were included in this review. Extensive resection, increased tumor size, and greater TNM staging were all associated with a greater number of LNs assessed. The disease-free survival was longer and recurrence rate was lower in patients with more LNs assessed. Overall survival, as well as survival by TNM and clinical stage, was improved among patients with an increased number of LNs assessed, but much of this appears to be due to stage migration, with the effect more pronounced in more advanced disease.

CONCLUSION

More LNs assessed resulted in less stage migration and possibly better long-term outcomes. Although current guidelines suggest 16 LNs to be assessed, especially in advanced GC, a higher number of LNs should be assessed.

Importance of and adherence to lymph node staging standards in gastrointestinal cancer

In gastrointestinal oncology, one of the most important factors influencing cancer-specific survival is the presence of positive lymph nodes. Although it remains controversial, adequate lymph node examination is required for accurate staging such that patients can receive appropriate adjuvant treatments and for stratification in clinical trials. Nevertheless, wide variation exists in the quality of lymph node examination in the United States, and many centers are not meeting guideline treatment recommendations.

Clinical implication of an insufficient number of examined lymph nodes after curative resection for gastric cancer

BACKGROUND

The seventh edition of the tumor, lymph node (LN), metastasis (TNM) staging system increased the required number of examined LNs in gastric cancer from 15 to 16. However, the same staging system defines lymph node-negative gastric cancer regardless of the number of examined LNs. In this study, the authors evaluated whether gastric cancer can be staged properly with fewer than 15 examined LNs.

METHODS

The survival rates of 10,010 patients who underwent curative gastrectomy from 1987 to 2007 were analyzed. The patients were divided into 2 groups according to the number of examined LNs, termed the "insufficient" group (≤15 examined LNs) and the "sufficient" group (≥16 examined LNs). The survival curves of patients from both groups were compared according to the seventh edition of the TNM classification.

RESULTS

Three hundred sixteen patients (3.2%) had ≤15 examined LNs for staging after they underwent standard, curative lymphadenectomy. Patients who had T1 tumor classification, N0 lymph node status, and stage I disease with an insufficient number of examined LNs after curative gastrectomy had a significantly worse prognosis than patients who had ≥16 examined LNs. Moreover, having an insufficient number of examined LNs was an independent prognostic factor for patients who had T1, N0, and stage I disease.

CONCLUSIONS

Lymph node-negative cancers in which ≤15 LNs were examined, classified as N0 in the new TNM staging system, could not adequately predict patient survival after curative gastrectomy, especially in patients with early stage gastric cancer.

Stage migration effect on survival in gastric cancer surgery with extended lymphadenectomy: the reappraisal of positive lymph node ratio as a proper N-staging

OBJECTIVE

The purpose of this study is to analyze the relationship between the number of examined lymph nodes (NexLN) and survival in gastric cancer and to determine whether the metastatic/examined lymph node ratio (LN ratio) system can compensate for the shortcomings of the UICC/AJCC staging.

METHODS

Prospective data of 8949 primary T1-T4a gastric cancer patients who underwent curative surgery were reviewed. The patients were stratified by T-stage and grouped according to NexLN; 1 to 14 exLN denoted the first group and every subsequent 10 LNs thereafter. Numbers of LN and 5-year survival rates were analyzed according to NexLN. "The NR-staging system" was generated using 0.2 and 0.5 as the cut-off values of LN ratio and then compared with UICC/AJCC stages.

RESULTS

The proportion of advanced N-stage increased with NexLN. Survival and the LN ratio were constant regardless of NexLN when combining all N0-N3b patients, however, T2/3 and T4a patients showed an increasing tendency toward survival in N1/2 and N3a as NexLN increased, mainly due to a stage migration effect. The LN ratio system showed better patterns of distribution of the LN stage and survival graph. The power of the differential staging of the LN ratio system was fortified with higher NexLN.

CONCLUSION

The relationship between NexLN and survival is probably affected by stage migration in a high-volume gastric cancer center. The LN ratio system could be a better option to compensate for this effect, and the value of the prognosis prediction in this system increases with a higher NexLN.

Preoperative chemotherapy does not influence the number of evaluable lymph nodes in resected gastric cancer

BACKGROUND

While it is suggested that more than 15 lymph nodes (LNs) should be evaluated for accurate staging of gastric cancer, LN yield in western countries is generally low. The effect of preoperative chemotherapy on LN yield in gastric cancer is unknown. The aim of the present study is to determine whether preoperative chemotherapy is associated with any difference in the number of LNs obtained from specimens of patients who underwent curative surgery for gastric adenocarcinoma.

PATIENTS AND METHODS

In 1205 patients from Memorial Sloan-Kettering Cancer Center (MSKCC) and 1220 patients from the Netherlands Cancer Registry (NCR) who underwent a gastrectomy with curative intent for gastric adenocarcinoma without receiving preoperative radiotherapy, LN yield was analyzed, comparing patients who received preoperative chemotherapy and patients who received no preoperative therapy.

RESULTS

Of the 2425 patients who underwent a gastrectomy, 14% received preoperative chemotherapy. Median LN yields were 23 at MSKCC and 10 in the NCR. Despite this twofold difference in LN yield between the two populations, with multivariate Poisson regression, chemotherapy was not associated with LN yield of either population. Variables associated with increased LN yield were institution, female sex, lower age, total (versus distal) gastrectomy and increasing T-stage.

CONCLUSIONS

In this patient series, treatment at MSKCC, female sex, lower age, total gastrectomy and increasing primary tumor stage were associated with a higher number of evaluated LNs. Preoperative chemotherapy was not associated with a decrease in LN yield. Evaluating more than 15 LNs after gastrectomy is feasible, with or without preoperative chemotherapy.

A descriptive analysis of gastric cancer specimen processing techniques

BACKGROUND

Adherence to guidelines for adequate gastric cancer specimen assessment is poor in North America. Inadequate staging and poor prognosis were noted in some series when these guidelines are not met. Recent advances have been made in standardizing cancer pathology reports in Canada; however, the uptake of these reporting systems is unknown for gastric cancer. A survey of pathologists in Ontario was performed to outline the processing techniques and practices for assessing gastric cancer specimens.

METHODS

A survey was designed through a collaboration of surgical oncologists, general surgeons, pathologists, and research staff. Pathologists were identified using the College of Physicians and Surgeons of Ontario and MD Select databases. Participants were surveyed online or by mail-out.

RESULTS

The response rate was 40.2% (147/366). Vascular invasion, perineural invasion, and signet ring cells were all reported as being examined for by the majority of pathologists. Fat clearing solution and keratin immunohistochemical techniques were not reported as being consistently utilized. Less than 70% of pathologists indicated using a form of synoptic report.

CONCLUSION

Variations in practice and technique were observed. This may or may not reflect differences in quality of care or simply preferences for achieving equivalent results in the absence of standardized procedures. Education, evidence-based procedural guidelines and further research are required to provide infrastructure and support for pathologists and surgeons involved in the care of gastric cancer patients.

Lymph node examination among patients with gastric cancer: variation between departments of pathology and prognostic impact of lymph node ratio

INTRODUCTION

At least 15 lymph nodes should be retrieved for proper TNM-staging in gastric cancer. We evaluated nodal harvest and examined its relation to stage distribution and survival at a population-based level, including the value of N-ratio (metastatic/evaluated) as a staging modality.

METHODS

All patients resected for primary M0 gastric cancer diagnosed in 1999-2007 in the Dutch Eindhoven Cancer Registry area were included (N = 880). Determinants of lymph node evaluation and their relationship with stage and survival were assessed in multivariable regression analyses. N-ratio categories were determined (N-ratio 0, 0%; N-ratio 1, 0.1%-19%; N-ratio 2, 20%-29%; N-ratio 3, ≥30%)

RESULTS

The median number of lymph nodes examined was 7, dependent on N-category (N0: 7; N+: 8). It varied between departments of pathology from 5 to 9. This variation remained after adjustment for relevant patient- and tumour factors. Stage distribution differed between pathology departments (proportion N0 ranging from 14% to 21%, p = 0.003). Among resected patients with N0M0 disease and <7 nodes examined, 5-year survival was 56%, compared to 69% among patients with ≥7 nodes examined (p = 0.012). Five-year survival for N-ratio 0 was 58%, N-ratio 1 50%, N-ratio 2 18% and N-ratio 3 11% (p < 0.0001), while 5-year survival ranged from 58% for N0, 17% for N1, and 11% for N2/3 (p < 0.0001).

CONCLUSION

In this series of patients with a relatively low number of evaluated lymph nodes, a high prognostic accuracy of N-ratio was found. However, improvement in nodal assessment is mandatory.