Feasible endoscopic therapy for early gastric cancer

Machine learning predicts lymph node metastasis of poorly differentiated-type intramucosal gastric cancer

To construct a machine learning algorithm model of lymph node metastasis (LNM) in patients with poorly differentiated-type intramucosal gastric cancer. 1169 patients with postoperative gastric cancer were divided into a training group and a test group at a ratio of 7:3. The model for lymph node metastasis was established with python machine learning. The Gbdt algorithm in the machine learning results finds that number of resected nodes, lymphovascular invasion and tumor size are the primary 3 factors that account for the weight of LNM. Effect of the LNM model of PDC gastric cancer patients in the training group: Among the 7 algorithm models, the highest accuracy rate was that of GBDT (0.955); The AUC values for the 7 algorithms were, from high to low, XGB (0.881), RF (0.802), GBDT (0.798), LR (0.778), XGB + LR (0.739), RF + LR (0.691) and GBDT + LR (0.626). Results of the LNM model of PDC gastric cancer patients in test group : Among the 7 algorithmic models, XGB had the highest accuracy rate (0.952); Among the 7 algorithms, the AUC values, from high to low, were GBDT (0.788), RF (0.765), XGB (0.762), LR (0.750), RF + LR (0.678), GBDT + LR (0.650) and XGB + LR (0.619). Single machine learning algorithm can predict LNM in poorly differentiated-type intramucosal gastric cancer, but fusion algorithm can not improve the effect of machine learning in predicting LNM.

Preoperative imaging evaluation of the absolute indication criteria for endoscopic submucosal dissection in early gastric cancer patients

Introduction

Gastric cancer (GC) is a common malignant tumor with a high mortality rate.

Aim

To determine the accuracy of preoperative imaging information obtained from the combined use of general gastroscopy (GS), endoscopic ultrasonography (EUS), and multi-detector computed tomography (MDCT) regarding absolute indication of endoscopic submucosal dissection (ESD) in early gastric cancer (EGC).

Material and methods

The relationship between clinical features of 794 EGC patients and lymph node metastasis (LNM) was analyzed. Multivariate logistic regression analysis was used to investigate the risk factors for LNM. Additionally, the accuracy of diagnosis of imaging techniques for ESD indications was determined by receiver operating characteristic (ROC) analysis.

Results

Data showed that tumor size > 2 cm (p = 0.0071), T1b stage (p < 0.0001), undifferentiated histology (p < 0.0001), and vascular invasion (p = 0.0007) were independent risk factors for LNM in patients with EGC. Indications for ESD have a specificity of 100% for the diagnosis of patients with LNM. Additionally, the diagnostic efficacy of the use of GS, EUS, and MDCT in identifying node positive status, T1a disease, tumor size ≤ 2 cm, and ulceration was found to be moderate with area under the curve (AUC) of receiver operating characteristic curve (ROC) of 0.71, 0.64, 0.72, and 0.68, respectively. Furthermore, the use of imaging techniques for overall indication criteria for ESD had a moderate utility value with an AUC of 0.71.

Conclusions

Our data suggested that, based on the combined use of GS, EUS, and MDCT, a high specificity of patient selection for ESD treatment can be achieved.

Tumor Budding and Other Risk Factors of Lymph Node Metastasis in Submucosal Early Gastric Carcinoma: A Multicenter Clinicopathologic Study in 621 Radical Gastrectomies of Chinese Patients

Compared with early gastric intramucosal carcinoma, submucosal carcinoma is known to have a higher risk for lymph node metastasis (LMN), but risk factors in submucosal carcinoma remain elusive. In this multicenter study with 621 radical gastrectomies for submucosal early gastric carcinoma, we investigated tumor budding and other risk factors of LMN that were identified in 172 cases (27.7%). Overall, independent high-risk factors for LMN included lymphovascular invasion (odds ratio, 3.9; 95% confidence interval, 2.5-6.1), tumor budding (odds ratio, 3.3; 95% confidence interval, 1.9-5.9), mixed tubular/papillary adenocarcinoma with poorly cohesive carcinoma (odds ratio, 2.1; 95% confidence interval, 1.0-4.3), and female sex (odds ratio, 1.6; 95% confidence interval, 1.0-2.6), whereas gastric cardiac submucosal carcinomas had a significantly lower risk for LMN (odds ratio, 0.5; 95% confidence interval, 0.3-0.9). In 276 well/moderately differentiated tubular or papillary submucosal early gastric carcinomas, independent risk factors were tumor budding (odds ratio, 3.7; 95% confidence interval, 1.6-8.7), deep submucosal (SM2) invasion (odds ratio, 3.1; 95% confidence interval, 1.3-7.6), and lymphovascular invasion (odds ratio, 2.7; 95% confidence interval, 1.3-5.6). In 174 cases without tumor budding and lymphovascular invasion, no LMN was identified in 47 cardiac tumors, and 15 tumors <1.0 cm in size. In conclusion, tumor budding, lymphovascular invasion, mixed tubular/papillary adenocarcinoma with poorly cohesive carcinoma, and female gender were found to be significant high-risk factors for LMN in submucosal early gastric carcinoma, while submucosal gastric cardiac carcinoma had a significantly lower risk for nodal metastasis.

Endoscopic management of patients with early gastric cancer before and after endoscopic resection: A review

With the wide application of endoscopic resection for early gastric cancer (EGC) by not only Asian endoscopists but also those from Western countries, reviews on standardized treatment processes before and after endoscopic resection are nevertheless lacking. In this article we provide a narrative review of studies on the selection of appropriate EGC for endoscopic resection and the follow-up strategies for those with histologically confirmed EGC after endoscopic resection. EGC should be comprehensively assessed before endoscopic resection, including its exact margin, invasive depth and risk of lymph node metastasis (LNM). While the curative resection status of EGC may be evaluated after endoscopic resection based on the newly developed eCura system, although this needs to be further verified. Surveillance with endoscopy and computed tomography scan is necessary for patients with an EGC level A or B. An additional endoscopic resection is recommended for patients with a level-C1 EGC. For patients with a level-C2 EGC, close follow-up is suggested for low-risk tumors of level C2 and additional surgery for those at high risks. Further postoperative strategy is suggested based on comprehensive assessment of the risk of LNM, patient's quality of life and wishes.

Risk factors of lymph node metastasis in 734 early gastric carcinoma radical resections in a Chinese population

OBJECTIVE

To investigate the risk factors of lymph node metastasis (LNM) in early gastric carcinoma (EGC) in a Chinese population.

METHODS

The data were analyzed to determine risk factors of LNM. The patients' characteristics, the tumor's location, gross features, histological type, differentiation, invasive depth, lymphovascular invasion (LVI), perineural invasion and the numbers of lymph nodes retrieved and involved were statistically analyzed.

RESULTS

A total of 734 patients with EGC were finally enrolled in the study, and LNM was present in 14.2% (104/734) of them. By univariate analysis, significant risk factors for LNM included depressed or excavated gross patterns, size ≥1.0 cm, SM2, moderate/poor differentiation, histological type of hepatoid or micropapillary adenocarcinoma, LVI, perineural invasion and tumor necrosis. By multivariate analysis, independent risk factors for LNM were size ≥3.0 cm (odds ratio [OR] 4.9), SM2 (OR 2.4), moderate (OR 3.6) and poor (OR 5.0) differentiation, LVI (OR 3.1) and tumor necrosis (OR 1.7). Early gastric cardiac carcinoma (OR 0.3) had a significantly lower risk than non-cardiac carcinoma. No LNM was identified in 67 EGC of <1.0 cm in size and without poor differentiation, in 142 intramucosal EGC cases of smaller than 2.0 cm and without poor differentiation, in 129 cases of well-differentiated EGC without deep SM2 submucosal invasion, or in 54 intramucosal EGC located in the gastric cardia.

CONCLUSION

Independent risk factors for LNM in EGC include tumor size ≥3.0 cm, SM2 invasion, moderate/poor differentiation, LVI and tumor necrosis. Early cardiac carcinoma had a significantly lower risk of LNM than non-cardiac EGC.

The Characteristics, Prognosis, and Risk Factors of Lymph Node Metastasis in Early Gastric Cancer

Background

Lymph node metastasis (LNM) is the most important risk factor for endoscopic treatment in early gastric cancer (EGC) patients. We aimed to investigate the rate of LNM, the risk factors, and the prognosis of EGC patients with LMN.

Methods

A total of 10,039 patients who underwent gastrectomy with lymphadenectomy were reviewed between January 2010 and December 2015 at Jiangsu Province Hospital in China. Among them, we identified 1004 (10%) EGCs. First, endoscopic and clinicopathological features related to LNM were analyzed, and then risk factors for LNM were identified using univariate and multivariate analysis. Finally, the short- and long-term outcomes were compared between the groups.

Results

LNM occurred in 123 (12.3%) EGCs. Most of EGCs were male (n = 720, 71.7%) and mean age was 59.65 ± 11.09 years. The rate of H. pylori infection was 78.0% (783/1004). LNM was significantly associated with age, sex, location, lesion size, macroscopic type, depth of invasion, differentiation type, histological morphology, lymphovascular invasion (LVI), and TMN stage. By multivariate analysis, significant independent risk factors for LNM in EGC were identified as following: male sex (OR 2.365, P = 0.035), age ≦ 40 (OR 0.055, P = 0.012), depressed type (OR 2.721, P = 0.013), submucosa invasion (OR 2.987, P = 0.032), LVI (OR 5.186, P = 0.003), tumor located in corpora (OR 8.904, P = 0.047), and in angle (OR 12.998, P = 0.024). 86.5% were successfully followed up for 3 years. The overall 1- and 3-year survival rates in LNM group were 100% and 91.1%, respectively, and those with no LNM were 100% and 100%, respectively.

Conclusion

EGCs were investigated in 10.0% of gastric cancer, which LNM occurred in 12.3% of EGC. Independent risk factors of LNM included male sex, age (>40), the depth of invasion, LVI, and tumor located in corpora or angle. The 3-year overall survival rate was greater in EGC patients without LNM.

Risk factors of lymph node metastasis in 1620 early gastric carcinoma radical resections in Jiangsu Province in China: A multicenter clinicopathological study

OBJECTIVE

To investigate risk factors of lymph node metastasis (LNM) in early gastric carcinoma (EGC) in four tertiary medical centers in Jiangsu Province, China.

METHODS

Among 10 097 consecutive combined gastric cancer radical resections, 1903 EGC were identified and reviewed, 283 excluded and 1620 included in the study. All pathological and some endoscopic reports were reviewed for patients' characteristics, tumor location, gross features, and the number of lymph nodes retrieved and involved. Two pathologists independently investigated the pathological features of tumor type, differentiation, invasion depth, lymphovascular invasion (LVI), and perineural invasion. The data were statistically analyzed to identify risk factors for LNM.

RESULTS

The average number of lymph nodes retrieved was 17.5 per patient. LNM was diagnosed in 15.5%. By univariate analysis, significant risk factors for LNM included age ≥ 41 years, female sex, size over 1 cm, submucosal invasion, poor differentiation, poorly cohesive carcinoma, micropapillary adenocarcinoma, adenocarcinoma mixed with signet-ring cell carcinoma, LVI, perineural invasion, and distal gastric location. By multivariate analysis, independent risk factors for LNM were size ≥ 3 cm (odds ratio [OR] 1.9), poor differentiation (OR 2.5), adenocarcinoma mixed with signet-ring cell carcinoma (OR 1.7), LVI (OR 5.8) and submucosal invasion (OR 2.9). In contrast, size < 3 cm and ulcer were not significant risk factors. Early cardiac carcinoma (OR 0.4) had significantly lower risk.

CONCLUSIONS

Independent risk factors for LNM in EGC in Chinese patients included tumor size ≥ 3 cm, poor differentiation, submucosal invasion, adenocarcinoma mixed with signet-ring cell carcinoma and LVI. Early cardiac carcinoma had a significantly lower risk for LNM.

Clinicopathology of Early Gastric Carcinoma: An Update for Pathologists and Gastroenterologists

BACKGROUND

The WHO defines early gastric carcinoma (EGC) as invasive carcinoma up to the submucosal layer, regardless of nodal metastasis. The recent study results indicate that EGC varies in location, histology, nodal metastasis, and prognosis.

SUMMARY

The heterogeneity in EGC may be related to various types of epithelial stem cells. The most important stem cells include Lgr5+ cells at the base of a gastric unit in the antrum-pylorus-cardia, Mist1+ cells at the isthmus/Troy+ cells at the base in the corpus-fundus, and Sox2+ cells at the base in almost all regions. Dysregulation of these cells along with environmental factors transform stem cells in different regions into malignancy in genetically susceptible populations.

KEY MESSAGE

The 2 most vulnerable regions for EGC have been found along the lesser curvature: the cardia in elderly patients and antrum-angularis in mid-aged and elderly patients. Most hereditary early-onset gastric carcinomas are concentrated in the corpus-fundus of young women. By histology, the most common EGC type is tubular adenocarcinoma in many growth patterns, starting in the neck of a gastric unit. Worse prognosis has been found in early papillary, compared to tubular, adenocarcinoma, related to deeper penetration, more lymphovascular invasion, and more liver and nodal metastases. Contrary to the common belief, intramucosal signet ring cell carcinoma demonstrates low risk of nodal metastasis, comparable to early intestinal-type EGC.

PRACTICAL IMPLICATIONS

The overall risk for nodal metastasis in EGC is low but significant. It is urgent to organize multicenter studies on risk of nodal metastasis in EGC in order to establish more reliable clinical practice guidelines to treat EGC patients.

Effect of World Health Organization (WHO) Histological Classification on Predicting Lymph Node Metastasis and Recurrence in Early Gastric Cancer

Background

The World Health Organization (WHO) histological classification for gastric cancer is widely accepted and used. However, its impact on predicting lymph node metastasis and recurrence in early gastric cancer (EGC) is not well studied.

Material/Methods

From 1987 to 2005, 2873 EGC patients with known WHO histological type who had undergone curative resection were enrolled in this study. In all, 637 well-differentiated adenocarcinomas (WD), 802 moderately-differentiated adenocarcinomas (MD), 689 poorly-differentiated adenocarcinomas (PD), and 745 signet-ring cell adenocarcinomas (SRC) were identified.

Results

The distribution of demographic and clinical features in early gastric cancer among WD, MD, PD, and SRC were significantly different. Lymph node metastasis was observed in 317 patients (11.0%), with the lymph node metastasis rate being 5.3%, 14.8%, 17.0%, and 6.3% in WD, MD, PD, and SRC, respectively. Univariate and multivariate analyses indicated that gender, tumor size, gross appearance, depth of invasion, and WHO classification were significantly associated with lymph node metastasis. Recurrence was observed in 83 patients (2.9%), with the recurrence rate being 2.2%, 4.5%, 3.0%, and 1.6% in WD, MD, PD, and SRC, respectively. Multivariate analysis confirmed that MD, elevated gross type, and lymph node metastasis were independent risk factors for recurrence in EGC. MD patients showed worse disease-free survival than non-MD patients (P=0.001).

Conclusions

WHO classification is useful and necessary to evaluate during the perioperative management of EGC. Treatment strategies for EGC should be made prudently according to WHO classification, especially for MD patients.

Risk factors of lymph node metastasis in early gastric carcinomas diagnosed by WHO criteria in 379 Chinese patients

OBJECTIVE

To investigate risk factors of lymph node metastasis (LNM) in Chinese early gastric carcinoma (EGC) patients diagnosed using the World Health Organization (WHO) criteria and compare the differences in those factors between proximal (PGC) and distal gastric carcinoma (DGC).

METHODS

Among 3 176 gastric cancer resections we identified 379 (11.9%) consecutive EGC (104 PGC and 275 DGC) with lymphadenectomy performed at the Affiliated Nanjing Drum Tower Hospital of Nanjing University (Nanjing, Jiangsu Province, China) between January 2005 and December 2012. Endoscopic and clinicopathological features related to LNM were analyzed.

RESULTS

LNM occurred in 49 (12.9%) EGC, including three PGC and 46 DGC. In early DGC, middle age (41-60 years), tumor size ≥3.1 cm, submucosal invasion, poorly cohesive carcinoma, micropapillary adenocarcinoma and lymphovascular invasion were risk factors by univariate analysis. In contrast, no risk factors of LNM were identified in early PGC. By multivariate analysis, female sex (odds ratio [OR] 2.4), DGC (OR 8.1), poorly cohesive carcinoma (OR 8.8) and lymphovascular invasion (OR 38.8) were found to be significant independent risk factors for LNM. The risk of LNM was effectively stratified using a scoring model of mild (score ≤3.5), moderate (score 4.0-8.5) and high (score ≥16) risk groups.

CONCLUSIONS

LNM occurred in 12.9% of EGC diagnosed with the WHO criteria in Chinese patients. Independent risk factors of LNM were identified in early DGC only and included female sex, DGC, poorly cohesive carcinoma and lymphovascular invasion. Early PGC has a much lower risk for LNM than early DGC.