Race/Ethnicity is predictive of lymph node status in patients with early gastric cancer

Survival Outcomes and Patterns of Care for Stage II or III Resected Gastric Cancer by Race and Ethnicity

Importance

Many multimodality treatment regimens exist for gastric adenocarcinoma, including neoadjuvant vs adjuvant chemotherapy, radiation, or both. Neoadjuvant therapy is recommended in the United States for patients with locally advanced gastric cancer; however, it is unknown whether the outcomes of neoadjuvant therapy are associated with race and ethnicity.

Objective

To evaluate the differences in outcomes by race and ethnicity of patients with noncardia gastric cancer undergoing surgical procedures with and without neoadjuvant therapy.

Design, Setting, and Participants

This retrospective cohort study examined the National Cancer Database from the American College of Surgeons for patients with clinical stage II or III gastric adenocarcinoma, excluding gastric cardia tumors, undergoing surgical resection procedures from January 2006 to December 2019. Statistical analysis was performed from December 2021 to May 2023.

Exposure

Patients were stratified by race and ethnicity, and their outcomes were analyzed for those who received and did not receive neoadjuvant therapy.

Main Outcomes and Measures

The Cox proportional hazard model was used to compare overall survival (OS) between racial and ethnic groups (Asian, Black, Hispanic, and White) overall and according to receipt of neoadjuvant therapy. Among those who received neoadjuvant therapy, proportional differences in pathological responses were calculated in each group.

Results

Among a total of 6938 patients in the cohort, 4266 (61.4%) were male; mean (SD) age was 65.9 (12.8) years; 1046 (15.8%) were Asian, 1606 (24.3%) were Black, 1175 (17.8%) were Hispanic, and 3540 (53.6%) were White. Compared with other races and ethnicities, the group of White patients had significantly more who were 65 years or older with more comorbidities. White patients underwent surgical resection procedures alone without neoadjuvant or adjuvant therapy more frequently than other races and ethnicities. Asian and Black patients had the highest proportion of being downstaged or achieving pathological complete response after neoadjuvant therapy. In multivariate models, perioperative chemotherapy was associated with improved OS (HR, 0.79 [95% CI, 0.69-0.90]), whereas number of positive lymph nodes and surgical margins were associated with the largest decreases in OS. Asian and Hispanic race and ethnicity were associated with significantly improved OS compared with Black and White races (eg, Asian patients: HR, 0.64 [95% CI, 0.58-0.72]; and Hispanic patients: HR, 0.77 [95% CI, 0.69-0.85]). Black race was associated with improved OS compared with White race when receiving neoadjuvant therapy (HR, 0.78 [95% CI, 0.67-0.90]).

Conclusions and Relevance

In this large nationwide cohort study of survival outcomes among patients with resected clinical stage II or III gastric cancer, there were significant differences in response to treatment and OS between different racial and ethnic groups.

Unique Genomic Alterations and Microbial Profiles Identified in Patients With Gastric Cancer of African, European, and Asian Ancestry: A Novel Path for Precision Oncology

OBJECTIVE

Here, we characterize differences in the genetic and microbial profiles of GC in patients of African (AFR), European, and Asian ancestry.

BACKGROUND

Gastric cancer (GC) is a heterogeneous disease with clinicopathologic variations due to a complex interplay of environmental and biological factors, which may affect disparities in oncologic outcomes..

METHODS

We identified 1042 patients with GC with next-generation sequencing data from an institutional Integrated Mutation Profiling of Actionable Cancer Targets assay and the Cancer Genomic Atlas group. Genetic ancestry was inferred from markers captured by the Integrated Mutation Profiling of Actionable Cancer Targets and the Cancer Genomic Atlas whole exome sequencing panels. Tumor microbial profiles were inferred from sequencing data using a validated microbiome bioinformatics pipeline. Genomic alterations and microbial profiles were compared among patients with GC of different ancestries.

RESULTS

We assessed 8023 genomic alterations. The most frequently altered genes were TP53 , ARID1A , KRAS , ERBB2 , and CDH1 . Patients of AFR ancestry had a significantly higher rate of CCNE1 alterations and a lower rate of KRAS alterations ( P < 0.05), and patients of East Asian ancestry had a significantly lower rate of PI3K pathway alterations ( P < 0.05) compared with other ancestries. Microbial diversity and enrichment did not differ significantly across ancestry groups ( P > 0.05).

CONCLUSIONS

Distinct patterns of genomic alterations and variations in microbial profiles were identified in patients with GC of AFR, European, and Asian ancestry. Our findings of variation in the prevalence of clinically actionable tumor alterations among ancestry groups suggest that precision medicine can mitigate oncologic disparities.

Risk of lymph node metastasis in early gastric cancer for a Western population

INTRODUCTION

Endoscopic resection (ER) of early gastric cancer (EGC) is increasingly used in Eastern countries due to their low rates of lymph node metastasis (LNM); however, there is a paucity of evidence in Western countries. We investigated LNM and its effect on overall survival (OS) in Western patients with EGC.

METHODS

Patients diagnosed with T1 gastric cancer between 2000 and 2017 were retrospectively evaluated. Univariate Kaplan-Meier, multivariate logistic and Cox-regression models were used to assess the associations between clinical characteristics, LNM, and OS.

RESULTS

Among 86 patients, median age was 68 years and 72% were male. Node positivity was 30%. Two percent of patients met the classical guidelines for ER and all were node-negative, while 16% met expanded criteria of which 14% were node-positive. T1b disease (odds ratio [OR] 41.2 [95% confidence interval [CI] 1.62-1048], p = 0.02) and lymphovascular/perineural invasion (OR 18.0 [95% CI 2.41-134], p = 0.01) were predictive of node positivity. The 5-year OS for node-negative and node-positive patients was 84% and 53% (p = 0.004), respectively.

CONCLUSIONS

The risk of LNM in Western patients with EGC is higher; therefore, generalizability of the expanded criteria for ER should be interpreted with caution.

The risk of lymph node metastasis in gastric cancer conforming to indications of endoscopic resection and pylorus-preserving gastrectomy: a single-center retrospective study

Background

Lymph node metastasis (LNM) status is an important prognostic factor that strongly influences the treatment decision of early gastric cancer (EGC). This study aimed to evaluate the pattern and clinical significance of LNM in EGC.

Methods

A total of 354 patients with carcinoma in situ (n = 42), EGC (n = 312) who underwent radical gastrectomy were enrolled. Their clinicopathological features, pathological reports, and prognostic data were collected and analyzed.

Results

The incidence of LNM in all patients was 18.36% (65/354). The rates of D1 and D2 station metastases were 12.10% (43/354) and 6.21% (22/354), respectively. The rates of LNM in absolute indication of endoscopic resection and expanded indication were 3.27% (2/61) and 28.55% (4/14), respectively. Skip LNM was observed in 3.67% (13/354) of patients. For those with middle-third tumor, the metastasis rate of the No. 5 lymph node was 3.05% (5/164). The independent risk factors for LNM were tumors measuring > 30 mm, poorly differentiated tumors, and lymphovascular invasion (all P < 0.05; area under the curve, 0.783). The 5-year disease-free survival rates of patients with and without LNM were 96.26 and 79.17%, respectively (P = 0.011). Tumors measuring > 20 mm and LNM were independent predictive factors for poor survival outcome in all patients.

Conclusions

Patients with EGC conforming to expanded indications have a relatively high risk of LNM and may not be suitable for endoscopic submucosal dissection. Pylorus-preserving gastrectomy for patients with middle-third EGC remains controversial due to the high metastasis rate of the No. 5 lymph node.

Barriers and Facilitators Associated with Delays in the Diagnosis and Treatment of Gastric Cancer: a Systematic Review

BACKGROUND

The present study was conducted to identify barriers and facilitators of early diagnosis and treatment of gastric cancer.

METHODS

Comprehensive search was conducted on 2021 in various databases, including Medline, Web of science, and Scopus. Keywords such as gastric cancer, screening programs, endoscopy, barriers, facilitators, and factor were used for the search, as single or in combination. Also a manual search was done in valid scientific journals to find related full-text articles. The search results were entered into the Endonote-X8 software, which automatically removes duplicate articles. Then, the title and the abstract and finally, the  text of the articles were studied. Articles that addressed barriers and facilitators of early diagnosis and treatment of gastric cancer were included.

RESULTS

In according to the results of 22 included articles, delay time in the diagnosis and treatment of gastric cancer were high, and factors such as age, sex, race and ethnicity, economic and social status, access to diagnostic services, implementation of screening programs, type and accuracy of screening methods, use of insurance services, error in care services, and presence of gastrointestinal symptoms were considered to be contributing factors in this regard.

CONCLUSIONS

It seems that to reduce delay in the diagnosis and treatment of gastric cancer, factors such as implementing screening programs using acceptable methods with high sensitivity and accuracy with a high level of participation, increasing insurance coverage and reducing the share of people in payments, increasing people's access to diagnostic services, educating people about the symptoms and risks of gastric cancer, undertaking proper follow-up in patients and suspects cases identified in screening, as well as increasing patients' access to medical services through financial and insurance support are significantly important.

Risk of lymph node metastasis in early gastric cancer and indications for endoscopic resection: is it worth applying the east rules to the west?

BACKGROUND

Early gastric cancers are associated with lymph node metastasis (LNM) in 15% of cases. Risk factors for LNM are well established in Eastern countries. Less invasive treatments, such as endoscopic or surgical laparoscopic resection, are well accepted in Eastern countries and a matter of intense debate in the West, were indications for such treatments are still contested The objective of the study is to determine risk factors related to LNM and to validate endoscopic resection indications.

METHODS

The study was a retrospective cohort of 178 patients with early gastric cancer who underwent gastrectomy. Clinical and pathological factors were analyzed. The new rules of ER from JGCA were applied to the studied cohort.

RESULTS

LNM was present in 13.48% of the cases, 3.96% (3/76) in T1a tumors and 20.58% (21/102) in T1b tumors. In univariate analysis ulceration (p = 0.04), differentiation grade (p = 0.04), submucosal invasion (p = 0.001), lymphatic invasion (p < 0.001), and vascular invasion (p < 0.001) were associated with LNM. In multivariate analysis, differentiation grade (p = 0.005) and submucosal invasion (p = 0.005) were independent risk factors. One patient classified in the expanded criteria group and seven from the relative criteria group had LNM. There were no LNM for undifferentiated mucosal lesions without ulceration.

CONCLUSIONS

Undifferentiated tumors and submucosal invasion are risks factors associated with LNM in early gastric cancer in our study. Endoscopic Resection or less invasive and radical surgical treatments are an option to be carefully considered.

The impact of endoscopic submucosal dissection for gastric adenocarcinomas in the United States

BACKGROUND AND AIMS

Recent studies show promise for endoscopic submucosal dissection (ESD) in the US, but do not identify the potential impact of ESD among newly diagnosed gastric cancers. We utilize the Veterans Health Administration to identify cancers suitable for ESD, to define the role of ESD in the US.

METHODS

Retrospective cohort study using the Veterans Affairs Central Cancer Registry to identify patients with gastric cancer who underwent surgical resection from 1995-2018. TNM stage was used to categorize those who would meet absolute vs expanded indications for ESD. Primary outcome was lymph node status. Secondary analysis was performed with death as outcome.

RESULTS

Of 12,584 primary gastric cancers, 4,735 (37.6%) were non-metastatic gastric adenocarcinomas. Median age at diagnosis was 70.3 years, 4,676 (98.8%) male. 2,306 (48.7%) underwent surgical resection, of which 636 (27.6%) were T1 lesions or cancer in situ. Of these, 44 (6.9%) met absolute indications for resection, 99 (15.6%) met established expanded criteria, and 98 (15.4%) may meet expanded criteria. Half of all tumors in each group were proximal in location.Rate of lymph node positivity was: 4.5%; 95% CI:0.5-15.5% in absolute group; 8.1%; 95% CI:3.6-15.3% in expanded group; 13.3%; 95% CI:7.3-21.6 in those potentially meeting expanded criteria. Lymph nodes positivity was associated with death (HR 1.49; 95% CI:1.36-1.62, p<0.001).

CONCLUSIONS

Less than 10% of T1 or in situ cancers meet absolute criteria for ESD. Those that meet expanded criteria had higher risk for lymph node metastases, particularly proximal tumors. Future studies should evaluate the safety of ESD in proximal gastric tumors.

Propensity score-matched comparison of short- and long-term outcomes between surgery and endoscopic submucosal dissection (ESD) for intestinal type early gastric cancer (EGC) of the middle and lower third of the stomach: a European tertiary referral center experience

BACKGROUND

Despite the comparable results between ESD and gastrectomy reported in multiple Asiatic studies, limited data are currently present on the long-term efficacy of ESD for EGC in Western countries. The aim of this study was to compare the short- and long-term outcomes of the endoscopic submucosal dissection and surgery for non-diffuse early gastric cancer treatment in a Western cohort of patients.

METHODS

All patients with a diagnosis of intestinal type EGC located in the middle and lower third of the stomach from 2005 to 2015 were enrolled in the study. All patients completed a 5-year follow-up. Patients were divided according to the procedure performed (ESD/subtotal gastrectomy). The two groups were matched for age, gender, ASA score, tumor dimension, and grade of infiltration (mucosa/submucosa).

RESULTS

After matching, 84 patients (42 per group) were included in the analysis. Peri-procedural morbidity rate was 7.1% and no difference was observed between the two groups (4.8% vs 9.5% for ESD and STG groups, respectively; p = 0.3). Similar results in terms of 5-year OS and DFS were observed for ESD and STG (77.7% vs 71.8% ; p = 0.78 and 74.9% vs 72% ; p = 0.7, respectively). At the multivariate analysis, ASA3 score was recognized as the only negative predictor factor for the 5-year OS (OR 6.2; 95% CI 2.2-16.8; p < 0.001). Regarding the DFS, both ASA3 score (OR 4.4; 95% CI 1.7-10.9; p < 0.001) and submucosal infiltration(OR 5.1; 95% CI 1.2-22.4 ; p = 0.02) were identified as independent risk factors for a worse outcome.

CONCLUSIONS

Our results confirm the safety and feasibility ESD for EGC treatment in a Western setting. In addition, this is one of the few reports showing comparable results both in terms of short- and long-term outcomes between ESD and surgery for intestinal type ECG treatment in Western countries.

The efficacy of treatment options for patients with gastric cancer and peritoneal metastasis

BACKGROUND

Patients with peritoneal metastases of gastric cancer have a poor prognosis and median survival of 7 months. This study compared treatment options and outcomes based on the Peritoneal Cancer Index (PCI).

METHODS

This retrospective analysis included patients with gastric cancer treated between August 2008 and December 2017 with synchronous peritoneal metastases only diagnosed by laparoscopy. The three treatments were as follows: (1) cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in combination with pre- and postoperative systemic chemotherapy (n = 58), (2) laparotomy/laparoscopy without CRS, but HIPEC in combination with pre- and postoperative systemic chemotherapy (n = 11), and (3) systemic chemotherapy only (n = 19).

RESULTS

A total of 88 patients aged 54.6 ± 10.9 years with mean PCI of 14.3 ± 11.3 were included. The PCI was significantly lower in group 1 (8.3 ± 5.7) than in group 2 (23.9 ± 11.1, p < 0.001) and group 3 (27.3 ± 9.3, p < 0.001). Mean time from diagnosis to laparoscopy was 5.2 ± 2.9 months. The median overall survival was 9.8 ± 0.7 for group 1, 6.3 ± 3.0 for group 2 and 4.9 ± 1.9 months for group 3 (p < 0.001). Predictors for deteriorated overall patient survival included > 4 cycles of preoperative chemotherapy (HR 4.49, p < 0.001), lymph-node metastasis (HR 3.53, p = 0.005), PCI ≥ 12 (HR 2.11, p = 0.036), and incompleteness of cytoreduction (HR 4.30, p = 0.001) in patients treated with CRS and HIPEC.

CONCLUSION

CRS and HIPEC showed convincing results in selected patients with PCI < 12 and complete cytoreduction. Prolonged duration (> 4 cycles) of preoperative intravenous chemotherapy reduced patient survival in patients suitable for CRS and HIPEC.

Adjuvant Therapy is Associated with Improved Survival in pT1N1 Gastric Cancer in a Heterogeneous Western Patient Population

BACKGROUND

Two recent South Korean studies showed adjuvant therapy (AT) was not associated with improved survival in pT1N1 gastric adenocarcinoma (GAC). We established the prognostic utility of lymph node status, determined the pattern of use of AT, and compared survival stratified by type of AT in pT1N1 GAC in a Western patient population.

METHODS

We identified patients with pT1N0 and pT1N1 GAC using the National Cancer Database from 2004 to 2012. Clinicopathologic variables, treatment regimens, and overall survival (OS) were compared.

RESULTS

We compared 4516 (86.6%) pT1N0 to 696 (13.4%) pT1N1 patients. pT1N1 tumors were larger (median size 2.5 vs. 1.8 cm, p < 0.001), more often poorly differentiated (56.2% vs. 39.6%, p < 0.001), and had higher median retrieved lymph nodes (RLN) (14 vs. 12, p < 0.001) compared with pT1N0. pT1N1 was associated with worse median overall survival (OS) (6.9 vs. 9.9 years for pT1N0, p < 0.001). pN1 was independently associated with worse OS (hazard ratio [HR] 2.17, 95% confidence interval [CI] 1.84-2.56). Increased RLN was associated with improved OS (HR 0.73, 95% CI 0.65-0.83). Among pT1N1 patients, 330 (47.4%) had observation (OBS), 77 (11.1%) received adjuvant chemotherapy (ACT), 68 (9.8%) received adjuvant radiation therapy (ART), and 221 (31.8%) received adjuvant chemoradiation therapy (ACRT). ACT and ACRT were independently associated with improved OS (HR 0.37, 95% CI 0.22-0.65 and HR 0.40, 95% CI 0.28-0.57).

CONCLUSIONS

pN1 was associated with worse survival and RLN ≥ 15 was associated with improved survival in pT1 GAC. ACT and ACRT were independently associated with improved survival in pT1N1 gastric cancer suggesting a valuable role in Western patients.

Introduction of endoscopic submucosal dissection in the West

Endoscopic submucosal dissection (ESD) is well established in Asia as a modality for selected advanced lesions of both the upper and lower gastrointestinal tract, but ESD has not attained the same niche in the West due to a variety of reasons. These include competition from traditional surgery, minimally invasive surgery and endoscopic mucosal resection. Other obstacles to ESD introduction in the West include time commitment for learning and doing procedures, a steep learning curve, special equipment, lack of mentors, cost issues, interdisciplinary conflicts, concern regarding complications and lack of support from institutions and interfacing departments. There are intrinsic differences in pathology prevalence (e.g., early gastric cancer) between the two regions that are less conducive for ESD implementation in the West. We will elaborate on these issues and suggest measures as well as a protocol to overcome these obstacles and hopefully allow introduction of ESD as a tenable option for appropriate patients.

Safety of expanded criteria for endoscopic resection of early gastric cancer in a Western cohort

Background

Endoscopic resection is widely accepted treatment option for early gastric cancer if tumors meet the standard or expanded indications. However, the safety of expanded criteria is still under investigation. Furthermore, discussion, if any additional treatment is necessary for patients who underwent endoscopic resection but exceeded expanded criteria, is rising. This study aimed to evaluate the safety of extended indications for endoscopic resection of early gastric cancer in a Western cohort. Also, we aimed to analyze the lymph node metastasis rate in tumors which exceeds the extended criteria.

Methods

Two hundred eighteen patients who underwent surgery for early gastric cancer at National Cancer Institute, Vilnius, Lithuania between 2005 and 2015 were identified from a prospective database. Lymph node status was examined in 197 patients who met or exceeded extended indications for endoscopic resection.

Results

Lymph node metastasis was detected in 1.7% of cancers who met extended indications and in 30.2% of cancers who exceeded expanded indications. Lymphovascular invasion and deeper tumor invasion is associated with lymph node metastasis in cancers exceeding expanded indications.

Conclusions

Expanded criteria for endoscopic resection of early gastric cancer in Western settings is not entirely safe because these tumors carry the risk of lymph node metastasis.

Risk factors for lymph node metastasis in early gastric cancer patients: Report from Eastern Europe country- Lithuania

BACKGROUND

Current risk factors for lymph node metastasis in early gastric cancer have been primarily determined in Asian countries; however their applicability to Western nations is under discussion. The aim of our study was to identify risk factors associated with lymph node metastasis in Western cohort patients from the Eastern European country - Lithuania.

METHODS

A total of 218 patients who underwent open gastrectomy for early gastric cancer were included in this retrospective study. After histolopathological examination, risk factors for lymph node metastasis were evaluated. Overall survival was evaluated and factors associated with long-term outcomes were analyzed.

RESULTS

Lymph node metastases were present in 19.7% of early gastric cancer cases. The rates were 5/99 (4.95%) for pT1a tumors and 38/119 (31.9%) for pT1b tumors. Submucosal tumor invasion, lymphovascular invasion, and high grade tumor differentiation were identified as independent risk factors for lymph node metastasis. Submucosal tumor invasion and lymphovascular invasion were also associated with worse 5-year survival results.

CONCLUSION

Our study established submucosal tumor invasion, lymphovascular invasion, and high grade tumor differentiation as risk factors for lymph node metastasis.

Race Is a Risk for Lymph Node Metastasis in Patients With Gastric Cancer

BACKGROUND

The frequency of lymph node metastasis in each T stage of gastric cancer has not been as well described for Western populations as it has for Asian populations. This study aimed to determine these frequencies and to investigate risk factors associated with lymph node metastases in a racially diverse U.S.

POPULATION

METHODS

A prospectively maintained database of 8260 patients with gastric or gastroesophageal junction adenocarcinoma treated at our institution from 1995 to 2013 was reviewed to identify those who underwent surgical resection without preoperative therapy. Associations between clinicopathologic variables and lymph node metastasis were tested with uni- and multivariate analyses.

RESULTS

The study identified 218 patients with a pathologic diagnosis of gastric adenocarcinoma who underwent upfront gastrectomy. These study subjects included 115 white (53 %), 19 black (9 %), and 41 Asian (19 %) patients. At least 15 lymph nodes were examined in 148 (68 %) of the patients. The lymph node metastasis rates were 10 % for stage T1a, 34 % for stage T1b, 44 % for stage T2, 73 % for stage T3, and 95 % for stage T4 tumors. Univariate analysis showed that submucosal invasion, race, 15 or more lymph nodes examined, and lymphovascular invasion were associated with lymph node metastasis in T1 and T2 tumors. The multivariate analysis showed all but lymphovascular invasion to be independent risk factors for nodal metastasis.

CONCLUSIONS

The rates of lymph node metastasis observed in this study were higher than those reported in Asian reports. Race was an independent risk factor for lymph node metastasis. Caution is therefore needed when evidence from Asian countries is extrapolated to more racially diverse Western countries.

Survival rates in T1 and T2 gastric cancer: A Western report

BACKGROUND AND OBJECTIVES

The purpose of this study was to identify clinicopathologic factors associated with overall survival (OS) in early T stage gastric cancer in a Western population.

METHODS

Patients with stage T1 or T2 gastric or gastroesophageal adenocarcinoma who had undergone upfront gastrectomy from 1995 to 2013 were identified in an institutional database.

RESULTS

We identified 121 patients with pathologic stage T1 or T2 tumors (49 [41%] T1a; 49 [41%] T1b; and 23 [19%] T2) who underwent R0 resection without preoperative treatment. Of these, 53% were white, 9% African American, 17% Hispanic, and 22% Asian. The median follow-up was 5.7 years, and the 5-year OS rate was 89% (98%, 93%, and 66% for patients with T1a, T1b, and T2 tumors, respectively). Univariate analysis revealed a higher risk of death in patients with T2 tumors and those of African American race. On multivariate analysis, T2 stage was the only variable independently associated with OS (hazard ratio, 2.80; 95% confidence interval, 1.11-7.12; P = 0.03).

CONCLUSION

In this study of a Western population of patients with T1 or T2 gastric cancer, T2 stage was associated with diminished OS, whereas nodal status and race were not. J. Surg. Oncol. 2016;114:602-606. © 2016 Wiley Periodicals, Inc.

Rates of lymph node metastasis and survival in T1a gastric adenocarcinoma in Western populations

BACKGROUND AND AIMS

EMR and endoscopic submucosal dissection (ESD) are widely accepted in Asia for treatment of early gastric cancer (EGC). Few studies have examined lymph node (LN) metastasis of EGC in Western populations. We sought to examine EGC and LN metastasis in a heterogeneous Western population.

METHODS

Patients with surgically resected, histologically confirmed American Joint Committee on Cancer T1a gastric adenocarcinoma were identified in the Surveillance, Epidemiology, and End Results (SEER) database from 2002 to 2012. Patients were excluded if they had stage IV disease, had multiple primary cancers, or received neoadjuvant therapy. Rates of LN metastasis were calculated, and survival analyses were performed.

RESULTS

Of 923 patients in the cohort, 72 (7.8%) had at least 1 positive LN on final pathology. When stratified by race, Asian/Pacific Islanders (APIs) demonstrated the lowest rate of LN metastases (n = 17/327, 5.2%), followed by Hispanics (n = 12/171, 7.0%), whites (n = 27/278, 9.7%), and blacks (n = 16/147, 10.9%). The highest rates of stage IA disease were observed in API (93.9%) and Hispanic (92.4%) patients, followed by white (89.9%) and black (87.1%) patients (P = .04). Survival analysis of T1a gastric cancer patients by race/ethnicity showed that 5-year overall survival was highest for API patients (API, 88%; Hispanic, 81%; black, 79%; and white, 77%; P < .01).

CONCLUSIONS

The rate of LN metastasis in T1a gastric cancers in the United States is higher than the rates reported in Asia. Survival outcomes in T1a gastric cancers varied significantly by race, suggesting that definitive endoscopic treatment may not be appropriate for all patients in the United States.

Upgrading the definition of early gastric cancer: better staging means more appropriate treatment

Since Murakami defined early gastric cancer (EGC) as a "carcinoma limited to the gastric mucosa and/or submucosa regardless of the lymph node status", several authors have focused on the most influential histopathological parameters for predicting the development of lymph node metastases by considering the lymph node status as an important prognostic factor. A few authors have also considered the depth of invasion as one of the keys to explaining the existence of subgroups of patients affected by EGC with poor prognoses. In any case, EGC is still considered an initial phase of tumor progression with good prognosis. The introduction of modern endoscopic devices has allowed a precise diagnosis of early lesions, which can lead to improved definitions of tumors that can be radically treated with endoscopic mucosal resection or endoscopic submucosal dissection (ESD). Given the widespread use of these techniques, the Japanese Gastric Cancer Association (JGCA) identified in 2011 the standard criteria that should exclude the presence of lymph node metastases. At that time, EGCs with nodal involvement should have been asserted as no longer fitting the definition of an early tumor. Some authors have also demonstrated that the morphological growth pattern of a tumor, according to Kodama's classification, is one of the most important prognostic factors, thereby suggesting the need to report it in histopathological drafts. Notwithstanding the acquired knowledge regarding the clinical behavior of EGC, Murakami's definition is still being used. This definition needs to be upgraded according to the modern staging of the disease so that the appropriate treatment would be selected.

Redefining early gastric cancer

BACKGROUND

The problem is that current definitions of early gastric cancer allow the inclusion of regional lymph node metastases. The increasing use of endoscopic submucosal dissection to treat early gastric cancer is a concern because regional lymph nodes are not addressed. The aim of the study was thus to critically evaluate current evidence with regard to tumour-specific factors associated with lymph node metastases in "early gastric cancer" to develop a more precise definition and improve clinical management.

METHODS

A systematic and comprehensive search of major reference databases (MEDLINE, EMBASE, PubMed and the Cochrane Library) was undertaken using a combination of text words "early gastric cancer", "lymph node metastasis", "factors", "endoscopy", "surgery", "lymphadenectomy" "mucosa", "submucosa", "lymphovascular invasion", "differentiated", "undifferentiated" and "ulcer". All available publications that described tumour-related factors associated with lymph node metastases in early gastric cancer were included.

RESULTS

The initial search yielded 1494 studies, of which 42 studies were included in the final analysis. Over time, the definition of early gastric cancer has broadened and the indications for endoscopic treatment have widened. The mean frequency of lymph node metastases increased on the basis of depth of infiltration (mucosa 6% vs. submucosa 28%), presence of lymphovascular invasion (absence 9% vs. presence 53%), tumour differentiation (differentiated 13% vs. undifferentiated 34%) and macroscopic type (elevated 13% vs. flat 26%) and tumour diameter (≤2 cm 8% vs. >2 cm 25%).

CONCLUSION

There is a need to re-examine the diagnosis and staging of early gastric cancer to ensure that patients with one or more identifiable risk factor for lymph node metastases are not denied appropriate chemotherapy and surgical resection.