Does a minimum number of 16 retrieved nodes affect survival in curatively resected gastric cancer?

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of gastric cancer, 2023

The 2023 update of the Chinese Society of Clinical Oncology (CSCO) Clinical Guidelines for Gastric Cancer focuses on standardizing cancer diagnosis and treatment in China, reflecting the latest advancements in evidence-based medicine, healthcare resource availability, and precision medicine. These updates address the differences in epidemiological characteristics, clinicopathological features, tumor biology, treatment patterns, and drug selections between Eastern and Western gastric cancer patients. Key revisions include a structured template for imaging diagnosis reports, updated standards for molecular marker testing in pathological diagnosis, and an elevated recommendation for neoadjuvant chemotherapy in stage III gastric cancer. For advanced metastatic gastric cancer, the guidelines introduce new recommendations for immunotherapy, anti-angiogenic therapy and targeted drugs, along with updated management strategies for human epidermal growth factor receptor 2 (HER2)-positive and deficient DNA mismatch repair (dMMR)/microsatellite instability-high (MSI-H) patients. Additionally, the guidelines offer detailed screening recommendations for hereditary gastric cancer and an appendix listing drug treatment regimens for various stages of gastric cancer. The 2023 CSCO Clinical Guidelines for Gastric Cancer updates are based on both Chinese and international clinical research and expert consensus to enhance their applicability and relevance in clinical practice, particularly in the heterogeneous healthcare landscape of China, while maintaining a commitment to scientific rigor, impartiality, and timely revisions.

Prognostic role of the number of resected and negative lymph nodes in Spanish patients with gastric cancer

INTRODUCTION

Lymph node (LN) involvement is one of the most critical prognostic factors in resected gastric cancer (GC). Some analyses, mainly conducted in Asian populations, have found that patients with a higher number of total lymph nodes (NTLN) and/or negative lymph nodes (NNLN) have a better prognosis, although other authors have failed to confirm these results.

MATERIALS AND METHODS

Retrospective study including all patients with GC resected in a tertiary hospital in Spain between 2001 and 2019 (n = 315). Clinicopathological features were collected and patients were categorized according to the NTLN and the NNLN. Statistical analyses were performed.

RESULTS

Mean NNLN was 17. The NNLN was significantly related to multiple clinicopathological variables, including recurrence and tumor-related death. The classification based on the NNLN (N1: ≥16, N2: 8-15, N3: ≤7) effectively stratified the entire cohort into three distinct prognostic groups and maintained its prognostic value within both the pN0 and pN+ patient subsets. Furthermore, it was an independent prognostic indicator for both overall and disease-free survival. Conversely, the mean NTLN was 21.9. Patients with ≤16 LN retrieved exhibited distinct clinicopathological features compared to those with >16 LN, but no significant differences were observed in terms of recurrence or disease-associated death. The application of alternative cut-off points for NTLN (10, 20, 25, 30, and 40) showed no prognostic significance.

CONCLUSIONS

In Spanish patients with resected GC the NNLN hold prognostic significance, while the NTLN does not appear to be prognostically significant. Incorporating the NNLN into GC staging may enhance the accuracy of the TNM system.

Prognostic Value of Tumor Size in Gastric Cancer: A Retrospective Cohort Study Based on SEER Database

Background. Although tumor size is regarded as the "T" stage of the tumor-node-metastasis (TNM) staging system for many solid tumors, its prognostic impact in gastric cancer remains uncertain and conflicting. Methods. We enrolled 6960 eligible patients from the Surveillance, Epidemiology, and End Results (SEER) database. The X-tile program was used to select the best cut-off value of tumor size. Then, the Kaplan-Meier method and the Cox proportional hazards model were applied to examine the efficacy of tumor size on prognostic prediction for overall survival (OS) and gastric cancer-specific survival (GCSS). The presence of nonlinear association was determined by the restricted cubic spline (RCS) model. Results. Tumor size was divided into 3 groups: small size (≤2.5 cm), medium size (2.6-5.2 cm), and large size (≥5.3 cm). After adjusting by covariates such as depth of tumor infiltration, the large and medium groups showed a worse prognosis than the small group; however, no survival difference in OS was suggested between the medium and large groups. Similarly, although there was a nonlinear relationship between tumor size and survival, increasing tumor size did not show an independent negative effect on prognosis in the RCS analysis. However, the stratified analyses proposed this 3-way cut of tumor size in prognostic prediction for patients with both inadequate lymphadenectomy and negative nodal metastasis. Conclusions. Tumor size as a prognostic predictor may not have good clinical applicability in gastric cancer. Otherwise, it was recommended for patients with both insufficient examinations of lymph nodes and stage N0 disease.

Development and validation of a novel nomogram for postoperative overall survival of patients with primary gastric signet-ring cell carcinoma: a population study based on SEER database

BACKGROUND

Gastric signet ring cell carcinoma (GSRCC) is a highly malignant subtype of gastric cancer. We tried to establish and validate a nomogram using common clinical variables to achieve more personalized management.

METHODS

We analyzed patients with GSRCC in the Surveillance, Epidemiology, and End Results database between 2004 and 2017. The survival curve was calculated by the Kaplan-Meier method, and the difference in survival curve was tested by log-rank test. We used the cox proportional hazard model to evaluate independent factors of prognosis, and established a nomogram to predict 1-, 3- and 5- overall survival (OS). Harrell's consistency index and calibration curve were used to measure the discrimination and calibration of the nomogram. In addition, we used decision curve analysis (DCA) to compare the net clinical benefits of the nomogram and American Joint Committee on Cancer (AJCC) staging system.

RESULTS

The prognosis nomogram predicting 1-, 3- and 5-years OS for patients with GSRCC is established for the first time. The C-index and AUC of nomogram were higher than that of the American Joint Committee on Cancer (AJCC) staging system in the training set. Our model also shows better performance than the AJCC staging system in the validation set, and importantly, DCA shows that our model has a better net benefit than the AJCC stage.

CONCLUSIONS

We have developed and validated a new nomogram and risk classification system, which is better than the AJCC staging system. It will help clinicians manage postoperative patients with GSRCC more accurately.

Signaling pathways and therapeutic interventions in gastric cancer

Gastric cancer (GC) ranks fifth in global cancer diagnosis and fourth in cancer-related death. Despite tremendous progress in diagnosis and therapeutic strategies and significant improvements in patient survival, the low malignancy stage is relatively asymptomatic and many GC cases are diagnosed at advanced stages, which leads to unsatisfactory prognosis and high recurrence rates. With the recent advances in genome analysis, biomarkers have been identified that have clinical importance for GC diagnosis, treatment, and prognosis. Modern molecular classifications have uncovered the vital roles that signaling pathways, including EGFR/HER2, p53, PI3K, immune checkpoint pathways, and cell adhesion signaling molecules, play in GC tumorigenesis, progression, metastasis, and therapeutic responsiveness. These biomarkers and molecular classifications open the way for more precise diagnoses and treatments for GC patients. Nevertheless, the relative significance, temporal activation, interaction with GC risk factors, and crosstalk between these signaling pathways in GC are not well understood. Here, we review the regulatory roles of signaling pathways in GC potential biomarkers, and therapeutic targets with an emphasis on recent discoveries. Current therapies, including signaling-based and immunotherapies exploited in the past decade, and the development of treatment for GC, particularly the challenges in developing precision medications, are discussed. These advances provide a direction for the integration of clinical, molecular, and genomic profiles to improve GC diagnosis and treatments.

The Association of Race With Adequate Lymph Node Evaluation for Gastric Cancer

BACKGROUND

National studies have reported racial and socioeconomic disparities in gastric cancer (GC) care. The current study evaluated adequate lymph node (LN) assessment (≥16 LNs) during resection for GC within a healthcare system servicing a socioeconomically disparate, mostly non-White population in the Southeast United States.

METHODS

A retrospective cohort study of patients undergoing resection for GC between 2003-2019 was performed. Factors associated with adequate LN assessment including patient and tumor characteristics were analyzed.

RESULTS

Among 202 patients, adequate LN assessment was performed in 97 (48%) patients. On univariable analysis, younger age, non-White race, lower Charlson Comorbidity Index (CCI), Medicaid or no insurance, D1+/D2 lymphadenectomy, clinical evidence of regional LN metastases, total gastrectomy, and receipt of neoadjuvant therapy were associated with adequate LN assessment. On multivariable analysis, non-White race (OR 2.79, 95% CI 1.38-5.65), CCI <4 (OR 2.14, 95% CI 1.15-3.96), and D1+/D2 lymphadenectomy (OR 3.63, 95% CI 1.96-6.74) were the only factors independently associated with adequate LN evaluation.

CONCLUSIONS

In the current study, non-White race, independent of socioeconomics, was significantly associated with adequate LN assessment. Future work is necessary to improve standardization and achieve higher rates of adequate LN assessment for all patients during resection for GC.

A Simple Predictive Index of the Abdominal Shape for Postoperative Complications After Laparoscopy-Assisted Distal Gastrectomy for Gastric Cancer

Background: The purpose of this study was to explore the effect of abdominal shape on the short-term surgical outcomes. Methods: This was a retrospective study that included 425 patients undergoing laparoscopic distal gastrectomy plus D2 lymph node dissection (LADG) from January 2013 to January 2021. The abdominal parameters, including the shortest distance of the pancreas from the anterior abdominal skin (PAAD), the lower sternum angle (LSA), the thickness of the subcutaneous fat at the navel level (SFT), the anteroposterior diameters (APD) and the left-right diameters (LRD) at the navel level, the distance from the xiphoid process to the navel (XND) and the distance from the xiphoid process to the pubis (XBD), were calculated by preoperative abdominal computed tomography (CT) imaging. The parameters and short-term surgical outcomes were analyzed. Results: In males, the number of retrieved lymph nodes was significantly higher in patients with a lower APD group (p = 0.031). The operation time was significantly shorter in the lower body mass index (BMI) (p = 0.007), lower LSA (p = 0.035), lower PAAD (p = 0.000), lower SFT (p = 0.004), lower APD (p = 0.000) and lower LRD (p = 0.014) groups. The estimated blood loss was significantly less in the lower BMI (p = 0.035), lower LSA (p = 0.001), lower PAAD (p = 0.012), lower SFT (p = 0.003), lower APD (p = 0.000) and lower LRD (p = 0.005) groups. The complications were fewer in the lower LSA (p = 0.012), lower APD (p = 0.043) and lower LRD (p = 0.023) groups. In females, the postoperative hospital stay was shorter in the lower PAAD (p = 0.027) and lower SFT (p = 0.004) groups, and the lower SFT group had fewer complications (p = 0.020). Furthermore, in multivariate analysis, higher PAAD (p = 0.037, odds ratio = 1.030, 95% CI = 1.002-1.059) was an independent factor for predicting postoperative complications in males. Conclusion: Various abdominal shapes can affect the difficulty of LADG. Higher PAAD is a simple independent index for predicting postoperative complications in males.

Endoscopic Versus Surgical Therapy for Early Esophagogastric Junction Adenocarcinoma Based on Lymph Node Metastasis Risk: A Population-Based Analysis

Background

In this study, we aimed to compare the prognosis and lymph node metastasis (LNM) risk in patients with early-stage esophagogastric junction (EGJ) adenocarcinoma after endoscopic treatment (ET) or radical surgery.

Methods

We collected data from eligible patients based on the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2016. Logistic regression analysis was used to determine independent predictors of LNM (examination of at least 16 lymph nodes). Cox regression analysis and propensity score-matched (PSM) analysis were subsequently utilized to compare the overall survival (OS) and cancer-specific survival (CSS) of patients treated with ET or radical surgery.

Results

In total, 3708 patients were identified. Among them, 856 patients had greater than or equal to 16 examined lymph nodes (LNs) (LNE≥16). The LNM rates were 18.8% in all patients 8.3% in T1a patients and 24.6% in T1b patients. Independent predictors of LNM were submucosal invasion, tumor size ≥3cm and decreasing differentiation (P<0.05). The LNM rate decreased to approximately 5.3% in T1b tumors with well differentiation and tumor size <3cm. However, the LNM incidence increased to 17.9% or 33.3% in T1a tumors with poor differentiation or with both tumor size≥3cm and poor differentiation. Cox regression analysis demonstrated CSS was not significantly different in early-stage EGJ adenocarcinoma patients undergoing ET and those treated with radical surgery (HR= 1.004, P=0.974), which were robustly validated after PSM analysis. Moreover, subgroup analysis stratified by T1a and T1b showed similar results.

Conclusions

The findings of this study indicated ET as an alternative to radical surgery in early EGJ adenocarcinoma.

Pathologic Lymph Node Staging of Gastric Cancer

OBJECTIVES

The TNM classification is the main tool for lymph node (LN) staging in gastric cancer (GC). However, alternative LN staging systems have been proposed, and the role of features other than the number of metastatic LNs is being investigated. Our aim is to discuss the main challenges of LN assessment in GC.

METHODS

Comprehensive review of the literature on alternative LN staging systems, examined LNs, sentinel LN (SLN) biopsy, LN micrometastases (LNMIs), extracapsular extension (ECE), and tumor deposits (TDs) in GC.

RESULTS

Many controversies exist regarding LN assessment in GC. The TNM classification shows excellent prognostic performance, but alternative prognostic methods such as the LN ratio or log odds of positive LNs have demonstrated to be better than the TNM system in terms of prognostic accuracy. The value of SLN biopsy and LNMIs in GC is still unclear, and several challenges concerning their clinical impact and pathologic analysis must be overcome before their introduction in clinical practice. Most authors have identified ECE and TDs as independent prognostic factors for survival in GC.

CONCLUSIONS

Further studies should be performed to evaluate the impact of these features on the TNM classification and patient outcomes, as well as to standardize alternative LN staging systems.

Proposed Quality Performance Indicators (QPI's) for axillary lymphadenectomy in metastatic cutaneous melanoma

INTRODUCTION

Axillary lymph node clearance (ALNC) continues to play a central role in the management of melanoma. However, what defines an adequate lymphadenectomy remains unclear. We aimed to propose Quality Performance Indicators (QPIs) for ALNC and to determine if the number of lymph nodes (LNs) removed impacts survival.

METHODS

We reviewed patients who underwent ALNC for melanoma at the Waitemata District Health Board and Melanoma Unit between February 2005 and October 2019, performed by two surgeons with standardized technique and surveillance.

RESULTS

105 patients with stage III melanoma were included, of which 73 had clinically evident disease and 32 had clinically occult disease. The mean total number of LNs excised was 29 (SD 10.90, range 10-76). On multivariate analysis, lymph node ratio (HR 4.48, 95% CI 1.55-12.93, p = 0.006), extracapsular spread (HR 2.53, 95% CI 1.06-6.05, p = 0.036) and distant recurrence (HR 11.24, 95% CI 3.79-33.31, p < 0.001) were significant predictors of mortality. The number of LNs removed did not predict survival outcomes, while the lymph node ratio did significantly predict survival outcomes. The regional recurrence rate was 3.8%.

DISCUSSION

We propose that QPIs for ALNC in melanoma include a 90th percentile LN yield of greater than 15, a mean LN yield of 20, a regional recurrence rate of less than 10%, and an overall complication rate of less than 50%.

CONCLUSION

The establishment of QPIs can help ensure that surgical oncology patients receive the highest quality of care.

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of gastric cancer, 2021

There exist differences in the epidemiological characteristics, clinicopathological features, tumor biological characteristics, treatment patterns, and drug selections between gastric cancer patients from the Eastern and Western countries. The Chinese Society of Clinical Oncology (CSCO) has organized a panel of senior experts specializing in all sub-specialties of gastric cancer to compile a clinical guideline for the diagnosis and treatment of gastric cancer since 2016 and renews it annually. Taking into account regional differences, giving full consideration to the accessibility of diagnosis and treatment resources, these experts have conducted expert consensus judgment on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes in China. The 2021 CSCO Clinical Practice Guidelines for Gastric Cancer covers the diagnosis, treatment, follow-up, and screening of gastric cancer. Based on the 2020 version of the CSCO Chinese Gastric Cancer guidelines, this updated guideline integrates the results of major clinical studies from China and overseas for the past year, focused on the inclusion of research data from the Chinese population for more personalized and clinically relevant recommendations. For the comprehensive treatment of non-metastatic gastric cancer, attentions were paid to neoadjuvant treatment. The value of perioperative chemotherapy is gradually becoming clearer and its recommendation level has been updated. For the comprehensive treatment of metastatic gastric cancer, recommendations for immunotherapy were included, and immune checkpoint inhibitors from third-line to the first-line of treatment for different patient groups with detailed notes are provided.

Retrieval of 30 Lymph Nodes Is Mandatory for Selected Stage II Gastric Cancer Patients

Background

According to the 8th edition AJCC staging manual, a least of 16 lymph nodes retrieval (LNRs) is the minimal requirement for lymph nodes (LNs) dissection of gastric cancer surgery. Previous studies have shown that increasing the number of LNRs (≥30) prolongs survival for selected patients. However, the necessity of retrieving 30 or more LN for stage II gastric cancer patients is still under debate.

Aim

This study aims to explore the impact of retrieving 30 or more lymph nodes on the survival of stage II cancer patients.

Methods

A total of 1,177 patients diagnosed with stage II gastric cancer were enrolled in this study. The clinicopathological parameters and the impact of different LNRs (<30 or ≥30) and positive lymph node ratio (NR) on overall survival (OS) were retrospectively analyzed.

Results

The mean number of LNRs was 34 ± 15. A total of 44% (518/1,177) of patients had an LNRs <30, while 56% (659/1,177) of patients had an LNRs ≥30. The 5-year survival rate was 81% for all patients, 76% for the LNRs <30 group, and 86% for LNRs ≥30 group, respectively (P = 0.003). The survival benefit of retrieving 30 lymph nodes was significant in certain subgroups: age >60 years/male/underwent total gastrectomy/stage IIB. For N+ patients, higher NR was significantly correlated with poor survival.

Conclusion

The survival benefit of retrieving 30 LNs varies in different subgroups. An LNRs of 30 is mandatory for selected stage II gastric cancer patients.

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.

Identifying Outlier Hospitals in Gastric Cancer Lymph Node Yield Using the National Cancer Database

BACKGROUND

Lymph node (LN) yield is a key quality indicator that is associated with improved staging in surgically resected gastric cancer. The National Comprehensive Cancer Network recommends a yield of ≥15 LNs for proper staging, yet most facilities in the United States fail to achieve this number. The present study aimed to identify factors that could affect LN yield on a facility level and identify outlier hospitals.

METHODS

This was a retrospective review of adults (aged ≥18 y) with gastric cancer (Tumor-Node-Metastasis Stages I-III) who underwent gastrectomy. Data were analyzed from the National Cancer Database (2004-2016). Multivariate analysis identified patient and tumor characteristics, whereas an observed-to-expected ratio of identified outlier hospitals. Facility factors were compared between high and low outliers.

RESULTS

A total of 26,590 patients were included in this study. Of these patients, only 50.3% had an LN yield ≥15. The multivariate model of patient and tumor characteristics demonstrated a concordance index was 0.684. A total of 1245 facilities were included. There were 198 low outlier LN yield hospitals and 135 high outlier LN yield hospitals (observed-to-expected ratio of 0.42 ± 0.24 versus 1.38 ± 0.19, P < 0.0001). There was a difference in facility type between low and high outliers (P < 0.0001). High LN yield hospitals had a larger surgical volume than low LN yield hospitals (median 8.4 [4.9, 13.5] versus 3.5 [2.4, 5.2]; P < 0.0001).

CONCLUSIONS

Nearly half of the population exhibited low compliance to National Comprehensive Cancer Network recommendations. Facility-level disparities exist as high yearly surgical volume and academic facility status distinguished high-performing outlier hospitals.

Modified ypTNM Staging Classification for Gastric Cancer after Neoadjuvant Therapy: A Multi-Institutional Study

BACKGROUND

The benefits of neoadjuvant therapy for patients with locally advanced gastric cancer (GC) are increasingly recognized. The 8th edition of the American Joint Committee on Cancer (AJCC) Staging Manual first proposed ypTNM staging, but its accuracy is controversial. This study aims to develop a modified ypTNM staging.

PATIENTS AND METHODS

Clinicopathological data of 1,791 patients who underwent curative-intent gastrectomy after neoadjuvant therapy in the Surveillance, Epidemiology, and End Results database, as the development cohort, were retrospectively analyzed. Modified ypTNM staging was established based on overall survival (OS). We compared the prognostic performance of the AJCC 8th edition ypTNM staging and the modified staging for patients after neoadjuvant therapy.

RESULTS

In the development cohort, the 5-year OS for AJCC stages I, II, and III was 58.8%, 39.1%, and 21.6%, respectively, compared with 69.9%, 54.4%, 34.4%, 24.1%, and 13.6% for modified ypTNM stages IA, IB, II, IIIA, and IIIB. The modified staging had better discriminatory ability (C-index: 0.620 vs. 0.589, p < .001), predictive homogeneity (likelihood ratio chi-square: 140.71 vs. 218.66, p < .001), predictive accuracy (mean difference in Bayesian information criterion: 64.94; net reclassification index: 35.54%; integrated discrimination improvement index: 0.032; all p < .001), and model stability (time-dependent receiver operating characteristics curves) over AJCC. Decision curve analysis showed that the modified staging achieved a better net benefit than AJCC. In external validation (n = 266), the modified ypTNM staging had superior prognostic predictive power (all p < .05).

CONCLUSION

We have developed and validated a modified ypTNM staging through multicenter data that is superior to the AJCC 8th edition ypTNM staging, allowing more accurate assessment of the prognosis of patients with GC after neoadjuvant therapy.

IMPLICATIONS FOR PRACTICE

The 8th edition of the American Joint Committee on Cancer (AJCC) Staging Manual first proposed ypTNM staging, but its accuracy is controversial. Based on multi-institutional data, this study developed a modified ypTNM staging, which is superior to the AJCC 8th edition ypTNM staging, allowing more accurate assessment of the prognosis of patients with gastric cancer after neoadjuvant therapy.

Prognostic impact of anatomical extent of metastatic lymph node on gastric cancer: a propensity score matching study

PURPOSE

Current gastric cancer staging systems overlook the anatomic extent of metastatic lymph nodes (AEMLNs). This study aimed to analyze the prognostic impact of AEMLNs on gastric cancer (GC).

METHODS

GC patients with metastatic lymph nodes (MLNs) undergoing curative surgery were retrospectively reviewed and assigned to perigastric (MLNs in station 1-6, PG) and extraperigastric group (7-12, with or without MLNs in PG area, EPG). Overall survival (OS), disease-free survival (DFS) and recurrence patterns were compared before and after 1:1 propensity score matching (PSM).

RESULTS

662 patients were enrolled, 341 (51.5%) and 321 (48.5%) of whom were in the PG and EPG, respectively. After PSM (n = 195), EPG showed poorer 5-year OS (43.4% vs 54.5%, p = 0.014) and DFS (65.0% vs 73.4%, p = 0.068) than PG. EPG had higher incidence of peritoneal recurrence (PR) than PG (19.4% vs 7.4%, p = 0.002). Multivariate analysis identified AEMLNs as prognostic factor for OS [HR = 1.409, 95% confidence interval (CI) 1.062-1.868), DFS (HR = 1.600, 95% CI 1.059-2.416) and PR (HR = 3.708, 95% CI 1.685-8.160).

CONCLUSIONS

The anatomic extent of metastatic lymph nodes has an independent prognostic role for GC. Including this element may improve the accuracy of current staging systems.

The clinicopathological characteristics and prognosis of patients with node-positive gastric cancer after curative surgery

BACKGROUND

Lymph node (LN) metastasis is one of the independent prognostic factors of gastric cancer (GC). The difference in survival rates and initial recurrence patterns in patients with node-positive GC with retrieved LN numbers greater than or less than 16 is worthy of further study.

METHODS

A total of 1314 patients with node-positive GC were enrolled. The clinicopathological characteristics, retrieved LN numbers, adjuvant chemotherapy, initial recurrence patterns, and survival differences between serosa-negative and serosa-positive GC were investigated.

RESULTS

For serosa-negative GC, patients with retrieved LN numbers ≥16 were associated with fewer tumor recurrences, locoregional recurrences, distant metastases, and better 5-year overall survival (OS) rates and disease-free survival (DFS) rates. For serosa-positive GC, patients with retrieved LN numbers ≥16 were associated with similar locoregional and distant metastasis and similar 5-year OS and DFS rates compared with those with retrieved LN numbers <16. Retrieved LN numbers fewer than 16 can cause stage migration compared with retrieved LN numbers ≥16. Multivariate analysis showed that both the retrieved LN numbers (≥ or <16) and adjuvant chemotherapy were independent prognostic factors affecting OS in serosa-negative GC, while adjuvant chemotherapy but not the retrieved LN numbers was an independent prognostic factor of OS in serosa-positive GC.

CONCLUSION

For serosa-negative GC, retrieved LN numbers fewer than 16 can cause stage migration, a higher tumor recurrence rate and worse OS and DFS rates compared with patients with retrieved LN numbers ≥16. Due to a high tumor recurrence rate in serosa-positive GC, adjuvant chemotherapy rather than retrieved LN numbers played an important role in improving patient prognosis.

Management of Gastric Adenocarcinoma for General Surgeons

Gastric cancer is one of the most common cancers in the world, despite declining incidence of the disease in the United States. Because of the rare occurrence of the disease in the United States, there is significant treatment variance in use of diagnostic modalities, neoadjuvant/adjuvant therapies, and surgical techniques. The survival of patients with gastric cancer in the United States is significantly lower than those of Asian countries where the diagnosis is made at an earlier stage and uniform high-quality treatment is delivered. This article reviews pearls and pitfalls of multidisciplinary management of the gastric adenocarcinoma for best outcomes.

Development and validation of prognostic nomogram based on log odds of positive lymph nodes for patients with gastric signet ring cell carcinoma

Objective

Our aims were to establish novel nomogram models, which directly targeted patients with signet ring cell carcinoma (SRC), for individualized prediction of overall survival (OS) rate and cancer-specific survival (CSS).

Methods

We selected 1,365 SRC patients diagnosed from 2010 to 2015 from Surveillance, Epidemiology and End Results (SEER) database, and then randomly partitioned them into a training cohort and a validation cohort. Independent predicted indicators, which were identified by using univariate testing and multivariate analyses, were used to construct our prognostic nomogram models. Three methods, Harrell concordance index (C-index), receiver operating characteristics (ROC) curve and calibration curve, were used to assess the ability of discrimination and predictive accuracy. Integrated discrimination improvement (IDI), net reclassification improvement (NRI) and decision curve analysis (DCA) were used to assess clinical utility of our nomogram models.

Results

Six independent predicted indicators, age, race, log odds of positive lymph nodes (LODDS), T stage, M stage and tumor size, were associated with OS rate. Nevertheless, only five independent predicted indicators were associated with CSS except race. The developed nomograms based on those independent predicted factors showed reliable discrimination. C-index of our nomogram for OS and CSS was 0.760 and 0.763, which were higher than American Joint Committee on Cancer (AJCC) 8th edition tumor-node-metastasis (TNM) staging system (0.734 and 0.741, respectively). C-index of validation cohort for OS was 0.757 and for CSS was 0.773. The calibration curves also performed good consistency. IDI, NRI and DCA showed the nomograms for both OS and CSS had a comparable clinical utility than the TNM staging system.

Conclusions

The novel nomogram models based on LODDS provided satisfying predictive ability of SRC both in OS and CSS than AJCC 8th edition TNM staging system alone.

Overweight or Obesity is an Unfavorable Long-Term Prognostic Factor for Patients who Underwent Gastrectomy for Stage II/III Gastric Cancer

BACKGROUND

Obesity has been reported to be a prognostic factor for many diseases in epidemiological studies; however, the results of studies examining the relationship between obesity and gastric cancer (GC) prognosis are inconsistent.

METHODS

A total of 460 patients with Stage II and III GC who underwent open R0 gastrectomy were included. Age, sex, body mass index (BMI classified into < 18.5, 18.5-25, and ≥ 25 kg/m²), stage, and postoperative adjuvant chemotherapy were analyzed to investigate the correlation with relapse-free survival (RFS).

RESULTS

Five-year RFS was 51% for the study patients. Five-year RFS values were 47.6%, 54.3%, and 40.1% for patients with BMI < 18.5, 18.5-25, and ≥ 25 kg/m², respectively. The forest plot for relapse risk according to BMI showed a U shape. Multivariate analysis for RFS showed significant differences in stage and BMI; the hazard ratio for recurrence in patients with BMI ≥ 25 kg/m² was 1.42 (95% confidence interval: 1.01-2.02, p = 0.0423) with reference to patients with BMI < 25 kg/m². BMI ≥ 25.0 was associated with longer operation times, more blood loss, fewer lymph nodes dissected, more frequent postoperative surgical site infection, and intra-abdominal abscesses.

CONCLUSIONS

BMI ≥ 25 kg/m² is an unfavorable prognostic factor for patients who underwent gastrectomy for Stage II and III GC.

Postoperative dynamic survival of gastric cancer patients: A multi-institutional, international analysis of 22 265 patients

BACKGROUND

How to best evaluate the disease-specific survival (DSS) of gastric cancer (GC) survivors over time is unclear.

METHODS

Clinicopathological data from 22 265 patients who underwent curative intend resection for GC were retrospectively analyzed. Changes in the patients' 3-year conditional disease-specific survival (CS3) were analyzed. We used time-dependent Cox regression to analyze which variables had long-term effects on DSS and devised a dynamic predictive model based on the length of survival.

RESULTS

Based on 1-, 3-, and 5-year survivorships, the CS3 of the population increased gradually from 62% to 68.1%, 83.7%, and 90.6%, respectively. Subgroup analysis showed that the CS3 of patients who had poor prognostic factors initially demonstrated the greatest increase in postoperative survival time (eg, N3b: 26.6%-84.1%, Δ57.5% vs N0: 84.1%-93.3%, Δ9.2%). Time-dependent Cox regression analysis showed the following predictor variables constantly affecting DSS: age, the number of examined lymph nodes (LNs), T stage, N stage, and site (P < .05). These variables served as the basis for a dynamic prediction model.

CONCLUSIONS

The influence of prognostic factors on DSS and CS3 changed dramatically over time. We developed an effective model for predicting the DSS of patients with GC based on the length of survival time.

A homogenized approach to classify advanced gastric cancer patients with limited and adequate number of pathologically examined lymph nodes

Background

The prognosis of gastric cancer patients with a limited number of pathologically examined lymph nodes (eLN, < 16) is dismal compared to those with adequately eLN (≥ 16), yet they are still classified within the same subgroups using the American Joint Committee on Cancer (AJCC) staging system. We aimed at formulating an easy-to-adopt and clinically reliable stratification approach to homogenize the classification for these two categories of patients.

Methods

Patients staged according to the 8th AJCC pathological nodal (N) and tumor-node-metastasis (TNM) classification were stratified into a Limited and Adequate eLN cohort based on their number of pathologically examined LNs. The statistical differences between the 5-year overall survival (OS) rates of both cohorts were determined and based on which, patients from the Limited eLN cohort were re-classified to a proposed modified nodal (N′) and TNM (TN′M) classification, by matching their survival rates with those of the Adequate eLN cohort. The prognostic performance of the N′ and TN′M classification was then compared to a formulated lymph-node-ratio-based nodal classification, in addition to the 8th AJCC N and TNM classification.

Results

Significant heterogeneous differences in 5-year OS between patients from the Limited and Adequate eLN cohort of the same nodal subgroups were identified (all P < 0.001). However, no significant differences in 5-year OS were observed between the subgroups N0, N1, N2, and N3a of the Limited eLN cohort when compared with N1, N2, N3a, and N3b from the Adequate eLN cohort, respectively (P = 0.853, 0.476, 0.114, and 0.230, respectively). A novel approach was formulated in which only patients from the Limited eLN cohort were re-classified to one higher nodal subgroup, denoted as the N′ classification. This re-classification demonstrated superior stratifying and prognostic ability as compared to the 8th AJCC N and lymph-node-ratio classification (Akaike information criterion values [AIC]: 12,276 vs. 12,358 vs. 12,283, respectively). The TN′M classification also demonstrated superior prognostic ability as compared to the 8th AJCC TNM classification (AIC value: 12,252 vs. 12,312).

Conclusion

The proposed lymph node classification approach provides a clinically practical and reliable technique to homogeneously classify cohorts of gastric cancer patients with limited and adequate number of pathologically examined lymph nodes.

Development and External Validation of Web-Based Models to Predict the Prognosis of Remnant Gastric Cancer after Surgery: A Multicenter Study

BACKGROUND

Remnant gastric cancer (RGC) is a rare malignant tumor with poor prognosis. There is no universally accepted prognostic model for RGC.

METHODS

We analyzed data for 253 RGC patients who underwent radical gastrectomy from 6 centers. The prognosis prediction performances of the AJCC7th and AJCC8th TNM staging systems and the TRM staging system for RGC patients were evaluated. Web-based prediction models based on independent prognostic factors were developed to predict the survival of the RGC patients. External validation was performed using a cohort of 49 Chinese patients.

RESULTS

The predictive abilities of the AJCC8th and TRM staging systems were no better than those of the AJCC7th staging system (c-index: AJCC7th vs. AJCC8th vs. TRM, 0.743 vs. 0.732 vs. 0.744; P>0.05). Within each staging system, the survival of the two adjacent stages was not well discriminated (P>0.05). Multivariate analysis showed that age, tumor size, T stage, and N stage were independent prognostic factors. Based on the above variables, we developed 3 web-based prediction models, which were superior to the AJCC7th staging system in their discriminatory ability (c-index), predictive homogeneity (likelihood ratio chi-square), predictive accuracy (AIC, BIC), and model stability (time-dependent ROC curves). External validation showed predictable accuracies of 0.780, 0.822, and 0.700, respectively, in predicting overall survival, disease-specific survival, and disease-free survival.

CONCLUSIONS

The AJCC TNM staging system and the TRM staging system did not enable good distinction among the RGC patients. We have developed and validated visual web-based prediction models that are superior to these staging systems.

The Chinese Society of Clinical Oncology (CSCO): clinical guidelines for the diagnosis and treatment of gastric cancer

China is one of the countries with the highest incidence of gastric cancer. There are differences in epidemiological characteristics, clinicopathological features, tumor biological characteristics, treatment patterns, and drug selection between gastric cancer patients from the Eastern and Western countries. Non-Chinese guidelines cannot specifically reflect the diagnosis and treatment characteristics for the Chinese gastric cancer patients. The Chinese Society of Clinical Oncology (CSCO) arranged for a panel of senior experts specializing in all sub-specialties of gastric cancer to compile, discuss, and revise the guidelines on the diagnosis and treatment of gastric cancer based on the findings of evidence-based medicine in China and abroad. By referring to the opinions of industry experts, taking into account of regional differences, giving full consideration to the accessibility of diagnosis and treatment resources, these experts have conducted experts’ consensus judgement on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic indexes. This guideline uses tables and is complemented by explanatory and descriptive notes covering the diagnosis, comprehensive treatment, and follow-up visits for gastric cancer.

Gastric cancer in Alaska Native people: A cancer health disparity

AIM

To evaluate recent trends in gastric cancer incidence, response to treatment, and overall survival among Alaska Native (AN) people.

METHODS

A retrospective analysis of the Alaska Native Medical Center patient database was performed. Patient history, clinical, pathological, response to treatment and patient outcomes were collected from one-hundred and thirty-two AN gastric cancer patients. The Surveillance, Epidemiology and End Result database 18 was used to collect comparison United States non-Hispanic White (NHW) and AN gastric cancer patient data between 2006-2014.

RESULTS

AN gastric cancer patients have a higher incidence rate, a poorer overall survival, and are diagnosed at a significantly younger age compared to NHW patients. AN patients differ from NHW patients in greater prevalence of non-cardia, diffuse subtype, and signet ring cell carcinomas. AN females were more likely to be diagnosed with later stage cancer, stage IV, compared to AN males. Diminished overall survival was observed among AN patients with increasing stage, O+ blood type, < 15 lymph nodes examined at resection, and no treatment. This study is the first report detailing the clinicopathologic features of gastric cancer in AN people with outcome data.

CONCLUSION

Our findings confirm the importance of early detection, treatment, and surgical resection for optimizing AN patient outcomes. Further research on early detection markers are warranted.

Staging and surgical approaches in gastric cancer: a clinical practice guideline

BACKGROUND

Resection is the cornerstone of cure for gastric adenocarcinoma; however, several aspects of surgical intervention remain controversial or are suboptimally applied at a population level, including staging, extent of lymphadenectomy (lnd), minimum number of lymph nodes that have to be assessed, gross resection margins, use of minimally invasive surgery, and relationship of surgical volumes with patient outcomes and resection in stage iv gastric cancer.

METHODS

Literature searches were conducted in databases including medline (up to 10 June 2016), embase (up to week 24 of 2016), the Cochrane Library and various other practice guideline sites and guideline developer Web sites. A practice guideline was developed.

RESULTS

One guideline, seven systematic reviews, and forty-eight primary studies were included in the evidence base for this guidance document. Seven recommendations are presented.

CONCLUSIONS

All patients should be discussed at a multidisciplinary team meeting, and computed tomography (ct) imaging of chest and abdomen should always be performed when staging patients. Diagnostic laparoscopy is useful in the determination of M1 disease not visible on ct images. A D2 lnd is preferred for curative-intent resection of gastric cancer. At least 16 lymph nodes should be assessed for adequate staging of curative-resected gastric cancer. Gastric cancer surgery should aim to achieve an R0 resection margin. In the metastatic setting, surgery should be considered only for palliation of symptoms. Patients should be referred to higher-volume centres and those that have adequate support to manage potential complications. Laparoscopic resections should be performed to the same standards as those for open resections, by surgeons who are experienced in both advanced laparoscopic surgery and gastric cancer management.

The IGCA staging system is more accurate than AJCC7 system in stratifying survival of patients with gastric cancer in stage III

Background

A new staging system recently proposed by the IGCA has demonstrated a better capacity of stratifying different prognoses for gastric cancer than the 7th edition AJCC staging system (AJCC7). The aim of this study was to evaluate the efficacy of the IGCA system in Chinese patients.

Methods

Medical records of patients with gastric cancer who received curative surgery in our center from January 2003 to December 2011 were reviewed retrospectively. All the lesions were staged according to both AJCC7 and IGCA staging systems. Overall survival (OS) of the patients was used as the observation endpoint.

Results

One thousand five hundred twenty-six cases were included in this study. By comparing the AJCC7 system with the IGCA systems, 395 cases were stratified into different stages, most of which were in stage III. The IGCA system could better stratify stage IIIB and IIIC patients (5-year OS, 38.1% vs. 29.0%; P = 0.005) than the AJCC7 system (5-year OS, 38.2% vs. 35.9%; P = 0.148). T3N3bM0, T4aN2M0 and T4aN3bM0 made up 97.5% (385/395) of the stage shift. T3N3bM0, which was stratified to stage IIIB in the AJCC7 system, showed a significant poorer prognosis than T4aN2M0 and T4aN3aM0, which were staged to IIIB and IIIC in the same system. The improper staging was revised in the IGCA staging system.

Conclusions

The IGCA staging system can stratify stage III gastric cancer patients more properly than the AJCC7 system.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3235-3) contains supplementary material, which is available to authorized users.

Prognostic impact of nodal status and therapeutic implications

The prognostic impact of lymph node (LN) metastases in gastric cancer is generally accepted. In primarily resected patients the pN-category and LN ratio are independent prognostic factors. Number of involved LNs, number of resected LNs, lymphangiosis and micrometastases also influence the prognosis significantly. To guarantee a proper D2 lymphadenectomy (LAD) at least 25 LNs according to the German S3 guidelines for the treatment of gastric cancer should be removed. Also in neoadjuvantly treated patients the ypN-category and LN ratio play an important prognostic role, despite the fact that UICC staging system was development based only on primarily resected patients. The role of response of LNs in neoadjuvantly treated patients is still unclear and needs further investigation. It seems to be less important than the response of the primary tumor. Limited data exists, suggesting that preoperative treatment might reduce the number of LNs involved and improve ypN-category. Due to further development in gastric cancer like laparoscopic resection and effective perioperative treatment in locally advanced tumor the role and the prognostic impact of LAD is again in the focus of discussion.

Does a Higher Cutoff Value of Lymph Node Retrieval Substantially Improve Survival in Patients With Advanced Gastric Cancer?-Time to Embrace a New Digit

BACKGROUND

The present study assessed the impact of the retrieval of >25 lymph nodes (LNs) on the survival outcome of patients with advanced gastric cancer after curative-intent gastrectomy.

PATIENTS AND METHODS

A total of 5,386 patients who had undergone curative gastrectomy for gastric cancer from 1994 to 2011 were enrolled. The clinicopathological parameters and overall survival (OS) were analyzed according to the number of LNs examined (≤15, n = 916; 16-25, n = 1,458; and >25, n = 3,012).

RESULTS

The percentage of patients with >25 LNs retrieved increased from 1994 to 2011. Patients in the LN >25 group were more likely to have undergone total gastrectomy and to have a larger tumor size, poorer tumor differentiation, and advanced T and N stages. Hospital mortality among the LN ≤15, LN 16-25, and LN >25 groups was 6.1%, 2.7%, and 1.7%, respectively (p < .0001). The LN >25 group consistently exhibited the most favorable OS, in particular, with stage II disease (p = .011) when OS was stratified according to tumor stage. Similarly, the LN >25 group had significantly better OS in all nodal stages (from N1 to N3b). The discrimination power of the lymph node ratio (LNR) for the LN ≤15, LN 16-25, and LN >25 groups was 483, 766, and 1,560, respectively. Multivariate analysis demonstrated that the LNR was the most important prognostic factor in the LN >25 group.

CONCLUSION

Retrieving more than 25 lymph nodes during curative-intent gastrectomy substantially improved survival and survival stratification of advanced gastric cancer without compromising patient safety. The Oncologist 2017;22:97-106Implications for Practice: D2 lymph node (LN) dissection is currently the standard of surgical management of gastric cancer, which is rarely audited by a third party. The present study, one of the largest surgical series worldwide, has shown that the traditionally recognized retrieval of ≥16 LNs during curative-intent gastrectomy might not be adequate in regions in which locally advanced gastric cancers predominate. The presented data show that retrieval of >25 LNs, which more greatly mimics D2 dissection, improves long-term outcomes and survival stratification without compromising patient safety.

Prognostic value of three different lymph node staging systems in the survival of patients with gastric cancer following D2 lymphadenectomy

The log odds of positive lymph nodes (LODDS) was defined as the log of the ratio between the number of positive lymph nodes and the number of negative lymph nodes, which is a novel and promising nodal staging system for gastric cancer. Here, we aimed to compare the prognostic effect of pN, lymph node ratio (LNR) and LODDS. The association between overall survival and pN, LNR and LODDS was retrospectively analysed. The discriminatory ability and monotonicity of gradients (linear trend χ (2) score), homogeneity ability (likelihood ratio test) and prognostic stratification ability (Akaike information criterion [AIC] and receiver operating characteristic [ROC] curve) were compared among three lymph node staging systems. The pN, LNR and LODDS were all identified as independent prognostic factors for gastric cancer patients in the multivariate analysis. LODDS showed the best prognostic performance (linear trend χ (2) score 266.743, likelihood ratio χ (2) test score 427.771, AIC value 5670.226, area under the curve (AUC) 0.793), followed by LNR and pN. In patients with different levels of retrieved lymph nodes (≤10, 11-14, 15-25 and >25), LODDS was the most powerful for prognostic prediction and discrimination of the heterogeneity among the subgroups. Significant differences in survival were observed among patients in different LODDS subgroups after being classified according to the pN and LNR classifications. LODDS appears to be a more powerful system for predicting the overall survival of gastric cancer patients, as compared to LNR and pN, and may serve as an alternative nodal staging system for gastric cancer.

Initial report of near-infrared fluorescence imaging as an intraoperative adjunct for lymph node harvesting during robot-assisted laparoscopic gastrectomy

INTRODUCTION

Adequate lymphadenectomy is a fundamental aspect of oncologically sound gastrectomies. Robot-assisted laparoscopic gastrectomy is a minimally invasive alternative that allows functional imaging to be easily integrated to the surgical field and may aid in intraoperative identification of lymphovascular bundles.

METHODS

Indocyanine green application and near-infrared fluorescence imaging were used during robot-assisted laparoscopic gastrectomy as an adjunct for the identification of relevant lymph node basins in real time.

RESULTS

A total of 31 patients were included. Twenty-nine gastrectomies were performed for adenocarcinoma and two wedge resections for neuroendocrine tumors. The mean lymph node retrieval was twenty-nine (range 17-61) for adenocarcinoma and five for neuroendocrine tumors. In all cases, at least five lymph nodes were seen along the main nodal basins, which provided real time intraoperative feedback regarding lymph node identification. Average time for indocyanine green application and functional imaging was less than 10 min.

CONCLUSIONS

Near-infrared fluorescent imaging may provide an improved method to help visualize lymph nodes intraoperatively during robot-assisted laparoscopic gastrectomy, thus adding a potentially valuable adjunct for lymphadenectomy and overall lymph node retrieval. J. Surg. Oncol. 2016;113:768-770. © 2016 Wiley Periodicals, Inc.