Clinical impact of the extent of lymph node micrometastasis in undifferentiated-type early gastric cancer

The Use of Deep Learning-Based Computer Diagnostic Algorithm for Detection of Lymph Node Metastases of Gastric Adenocarcinoma

Objectives. The diversifying modalities of treatment for gastric cancer raise urgent demands for the rapid and precise diagnosis of metastases in regional lymph nodes, thereby significantly impact the workload of pathologists. Meanwhile, the recent advent of whole-slide scanners and deep-learning techniques have enabled the computer-assisted analysis of histopathological images, which could help to alleviate this impact. Thus, we developed a deep learning-based diagnostic algorithm to detect lymph node metastases of gastric adenocarcinoma and evaluated its performance. Methods. We randomly selected 20 patients with gastric adenocarcinoma who underwent surgery as definitive treatment and were found to be node metastasis-positive. HEMATOXYLIN-eosin (HE) stained glass slides, including a total of 51 metastasis-positive nodes, were retrieved from the specimens of these cases. Other slides with 776 metastasis-negative nodes were also retrieved from other twenty cases with the same disease that were diagnosed as metastasis-negative by the final pathological examinations. All glass slides were digitized using a whole-slide scanner. A deep-learning algorithm to detect metastases was developed using the data in which metastasis-positive parts of the images were annotated by a well-trained pathologist, and its performance in detecting metastases was evaluated. Results. Cross-validation analysis indicated an area of 0.9994 under the receiver operating characteristic curve. Free-response receiver operating characteristic curve (FROC) analysis indicated a sensitivity of 1.00 with three false positives. Further evaluation using an independent dataset also showed similar level of accuracies. Conclusion. This deep learning-based diagnosis-aid system is a promising tool that can assist pathologists involved in gastric cancer care and reduce their workload.

Clinicopathological characteristics of advanced gastric cancer after Helicobacter pylori eradication

Background and Aim

Helicobacter pylori (H. pylori) eradication has become popular as it prevents the development of gastric cancer. There have been no comprehensive studies on advanced gastric cancer (AGC) after eradication; thus, the clinical characteristics remain unclear. This study aimed to compare the characteristics of AGC after eradication and with current H. pylori infection and evaluate the esophagogastroduodenoscopy (EGD) follow-up after eradication.

Methods

This single-center, retrospective study included 261 consecutive patients diagnosed with AGC through EGD. The patients were grouped based on their H. pylori status: eradication (n = 48) and infection (n = 213) groups. Univariate analysis was conducted to compare clinicopathological characteristics between groups. The clinical course of the eradication group was analyzed by dividing the patients into three groups according to the interval from the last EGD until AGC detection: short-interval (<1 year), intermediate-interval (2-3 years), and long-interval (4-5 years) groups.

Results

The radical resection (R0) rate was higher in the eradication group. In surgical cases, the median tumor diameter was shorter in the eradication group. Analysis of EGD surveillance after eradication in 36 available cases showed that 24 (66.7%) were detected within 5 years after eradication, and 3 (8.3%) were diagnosed as AGC > 20 years after eradication. The R0 rates in the short-, intermediate-, and long-interval groups were 83.3%, 71.4%, and 60%, respectively.

Conclusions

AGC after eradication was more often detected at the phase in which R0 resection was possible. EGD follow-up with tight intervals of at least 5 years after eradication is advisable.

Clinical Significance of Metastasis or Micrometastasis to the Lymph Node Along the Superior Mesenteric Vein in Gastric Carcinoma: A Retrospective Analysis

Background

The validity of lymphadenectomy of the lymph node along the superior mesenteric vein (LN14v) in gastric cancer remains controversial. The study investigated the characteristics and prognosis of gastric cancer with metastasis or micrometastasis to LN14v.

Methods

A retrospective study of 626 patients undergoing radical gastrectomy in our center from January 2003 to December 2015 was analyzed. In total, 303 patients had lymphadenectomy of LN14v, and lymph node micrometastasis was evaluated by immunohistochemical staining for cytokeratin nodes CK8/18. A logistic regression model was applied to confirm the predictive factors of micrometastasis. Survival analysis was performed to evaluate the effect of micrometastasis or metastasis on prognosis.

Results

The metastatic rate of the LN14v lymph node was 15.8%, and the micrometastatic rate was 3.3%. Multivariate analysis showed site, Borrmann classification, postoperative lymph node metastasis (pN), and metastasis in LN6 and LN9 were predictive factors for LN14v micrometastasis or metastasis (P < 0.05). The 5-year survival rate in the positive group (LN14v micrometastasis or metastasis) was 12.4%. The prognosis of patients without LN14v lymph node micrometastasis was better than that of the positive group, whereas the difference between group of LN14v micrometastasis and LN14v metastasis was not obvious. In matched analysis, patients with stage III gastric cancer L/M area, pN2-3, and LN6(+) who underwent lymphadenectomy of LN14v had better survival than those without lymphadenectomy of LN14v.

Conclusion

Lymph node micrometastasis may provide accurate prognostic information for patients with gastric cancer. Moreover, lymphadenectomy of LN14v might improve the survival of patients with stage III gastric cancer of L/M area, pN2-3, and LN6(+).

Lymphovascular Invasion: Traditional but Vital and Sensible Prognostic Factor in Early Gastric Cancer

BACKGROUND

Although patients with early gastric cancer have good prognosis, recurrence after treatment may occur. Lymphovascular invasion (LVI) in gastric cancer has long been suggested as a poor prognostic indicator. This study sought to evaluate the prognostic effect of LVI in patients with early gastric cancer.

METHODS

From 2005 to 2016, 6516 patients with early gastric cancer who underwent radical gastrectomy were analyzed. The patients were categorized according to LVI and lymph node (LN) status.

RESULTS

LVI was present in 853 patients (13.1%). Patients with LVI or LN metastasis had more aggressive tumor characteristics than patients without both LVI and LN metastasis. The overall and relapse-free survival in patients with LVI were significantly worse than in patients without LVI. When we compared the survival rate of patients stratified by LVI and LN status, there was a significant overall and relapse-free survival difference between patients without both LVI and LN metastasis compared with those with LVI but without LN metastasis (p < 0.001). The overall and relapse-free survival of patients with LVI but without LN metastasis were similar to those without LVI but with LN metastasis (p = 0.818). Patients with LVI or LN metastasis showed a high frequency of recurrence (p < 0.001). Multivariate analysis showed that LVI and LN status were independent risk factors for relapse-free survival of early gastric cancer patients.

CONCLUSIONS

Early gastric cancer with LVI is associated with poor prognosis and frequent recurrence. When predicting the prognosis of patients with early gastric cancer, LVI should be considered.

Comparison between endoscopic submucosal resection and surgery for the curative resection of undifferentiated-type early gastric cancer within expanded indications: a nationwide multi-center study

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) for undifferentiated early gastric cancer (UD EGC) has debate due to the risk of lymph node metastasis. We investigated the outcomes of ESD compared to those of surgery for the UD EGC within expanded indication.

METHODS

We reviewed 971 UD EGC patients performed ESD across 18 hospitals in Korea and 1812 patients who underwent surgical resection in two hospitals between February 2005 and May 2015. Of these cases, we enrolled a curative resected ESD group of 328 patients and surgery group of 383 cases within an expanded indication. Overall outcomes and one-to-one propensity score-matched (218 ESD group vs 218 surgery group cases) outcomes for these two groups were analyzed.

RESULTS

Over the 75.6 month median follow-up period for the 711 enrolled cases, recurrences occurred in 22 patients (6.7%) in the ESD group but not in the surgery group. Overall survival (OS) was higher in the surgery group (p = 0.0316) in all cases, but there was no significant difference after propensity score matching (p = 0.069). According to the histologic type in propensity score matching, the OS of signet ring cell carcinoma and poorly differentiated carcinoma patients did not differ between the ESD and surgery groups (p = 0.1189 and p = 0.3087, respectively). In the surgery group involving expanded criteria, lymph node metastasis was found in six cases (1.56%).

CONCLUSIONS

Although ESD shows comparable outcomes to surgery for the UD EGC within expanded indications, appropriate patient selection is needed for the ESD due to the possibility of lymph node metastasis.

A genomic-clinicopathologic Nomogram for the preoperative prediction of lymph node metastasis in gastric cancer

BACKGROUND

Preoperative evaluation of lymph node (LN) state is of pivotal significance for informing therapeutic decisions in gastric cancer (GC) patients. However, there are no non-invasive methods that can be used to preoperatively identify such status. We aimed at developing a genomic biosignature based model to predict the possibility of LN metastasis in GC patients.

METHODS

We used the RNA profile retrieving strategy and performed RNA expression profiling in a large GC cohort (GSE62254, n = 300) from Gene Expression Ominus (GEO). In the exploratory stage, 300 GC patients from GSE62254 were involved and the differentially expressed RNAs (DERs) for LN-status were determined using the R software. GC samples in GSE62254 were randomly allocated into a learning set (n = 210) and a verification set (n = 90). By using the Least absolute shrinkage and selection operator (LASSO) regression approach, a set of 23-RNA signatures were established and the signature based nomogram was subsequently built for distinguishing LN condition. The diagnostic efficiency, as well as the clinical performance of this model were assessed using the decision curve analysis (DCA). Metascape was used for bioinformatic analysis of the DERs.

RESULTS

Based on the genomic signature, we established a nomogram that robustly distinguished LN status in the learning (AUC = 0.916, 95% CI 0.833-0.999) and verification sets (AUC = 0.775, 95% CI 0.647-0.903). DCA demonstrated the clinical value of this nomogram. Functional enrichment analysis of the DERs was performed using bioinformatics methods which revealed that these DERs were involved in several lymphangiogenesis-correlated cascades.

CONCLUSIONS

In this study, we present a genomic signature based nomogram that integrates the 23-RNA biosignature based scores and Lauren classification. This model can be utilized to estimate the probability of LN metastasis with good performance in GC. The functional analysis of the DERs reveals the prospective biogenesis of LN metastasis in GC.

Differential prognostic implications of gastric adenocarcinoma based on Lauren's classification: a Surveillance, Epidemiology, and End Results (SEER)-based cohort study

Background

Our study aims to analyze the association between Lauren's classification and gastric adenocarcinoma prognosis using comprehensive statistical analyses.

Methods

According to the selection criteria, patients were included from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox regression, propensity score matching, and a multivariate competing risk model were used to investigate the association between Lauren's classification and prognosis. Subgroup analysis was used to investigate the role of confounding factors on the association between Lauren types and prognosis.

Results

After exclusion, a total of 20,218 patients from the SEER database were included, with 14,374 intestinal types and 5,844 diffuse types. The univariate Cox regression analysis revealed that the diffuse type had a poorer cancer-specific survival (CSS) rate [hazard ratio (HR), 1.44; 95% confidence interval (CI), 1.38-1.50]. After adjusting for confounding variables, the diffuse type also showed a higher risk of cancer-specific death (HR, 1.20; 95% CI, 1.15-1.20). Sensitivity analysis showed that after propensity score matching, the diffuse type had a poorer CSS rate (HR, 1.23; 95% CI, 1.10-1.36), and the competing risk model further validated these results [subdistribution HR (SHR), 1.32; 95% CI, 1.23-1.41]. Moreover, subgroup analysis demonstrated stable results in the subgroups, except for patients with T1 stage (HR, 1.06; 95% CI, 0.87-1.28) and a tumor size <2 cm (HR, 1.00; 95% CI, 0.83-1.21).

Conclusions

Diffuse-type gastric adenocarcinoma had an overall poorer prognosis compared to the intestinal type. However, in patients with T1 stage and tumor size <2 cm, the diffuse type had a comparable survival rate with the intestinal type.

KK-LC-1 may be an effective prognostic biomarker for gastric cancer

Background

The objective of the study was to detect the expression of Kita-Kyushu lung cancer antigen-1 (KK-LC-1) in gastric cancer (GC) specimens and analyse the associations between KK-LC-1 expression and clinicopathological parameters and clinical prognosis.

Methods

All of the 94 patients in this study were GC patients who underwent surgical resection. KK-LC-1 protein expression in GC tissue was detected by immunohistochemistry. This report applies the histological score (H-score) to evaluate KK-LC-1 expression. To calculate this indicator, the number of positive cells in each section and their staining intensity were converted to corresponding values. The expression of KK-LC-1 in the cytoplasm of cancer and normal tissues was scored to obtain their respective H values. The chi-square test, Kaplan-Meier method and Cox regression were used to analyse the linear association between KK-LC-1 expression and clinicopathological data and prognosis.

Results

In the cytoplasm, KK-LC-1 expression in tumour tissues was significantly higher than that in normal tissues (P < 0.001). Using the median H-score as the cut-off value, we discovered that GC patients with high levels of KK-LC-1 expression in the cytoplasm had favourable overall survival (OS) (P = 0.016), and this result was statistically significant in the Cox regression analysis. Additionally, a negative correlation was found between KK-LC-1 protein expression and the pathological grade of the tumour (P = 0.036), with significantly more KK-LC-1 protein expression observed in the intestinal type of GC than in the diffuse type (P = 0.008).

Conclusions

Our research data showed that KK-LC-1 expression was greater in GC tissues than in normal tissues, and higher KK-LC-1 expression was associated with longer OS of GC patients. KK-LC-1 can be used as a biomarker for a good prognosis in GC patients.

Risk factors and prognosis of bone metastases in newly diagnosed gastric cancer

Aim: To predict the occurrence of bone metastases and prognosis among patients with gastric cancer on a population level. Materials & methods: Data were obtained from the SEER database (2010-2016). Multivariable logistic regression and multivariable Cox regression were used to determine factors that predict the occurrence of bone metastasis and prognosis. Results: Cardia cancer, younger age, white race, poor differentiation grade, higher N stage, diffuse-type were positively associated with the presence of bone metastasis. For gastric cancer patients with bone metastasis, the median survival time was longer (9.0 months) among patients with surgery of primary site compared with those without surgery (3.0 months). Conclusion: According to the results of risk assessment, clinical efforts should be targeted to focus on screening high-risk patients.

Comparable rates of lymph node metastasis and survival between diffuse type and intestinal type early gastric cancer patients: a large population-based study

BACKGROUND AND AIMS

Limited evidence and contradictory results exist regarding the impact of Lauren type, namely diffuse and intestinal types, of lymph node metastasis (LNM) and prognosis for early gastric cancer (EGC). We aimed to compare LNM and prognosis between diffuse and intestinal type EGCs using comprehensive statistical analysis.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify all patients with surgically resected, histologically diagnosed, intestinal or diffuse type EGC. Multivariate logistic regression, multivariate Cox regression, multivariate competing risk model, and propensity score matching were used to analyze association the Lauren type and LNM or prognosis.

RESULTS

We identified 5593 EGCs from the SEER database, including 4376 intestinal types and 1217 diffuse types. No positive association was found between LNM and Lauren type (odds ratio, .93; 95% confidence interval [CI], .70-1.24; P = .62) after adjustment for other risk factors. Moreover, diffuse-type EGCs showed a similar prognosis to intestinal type EGCs in both multivariate Cox regression (HR [hazard ratio], .95; 95% CI, .77-1.18; P = .66) and the multivariate competing risk model (subdistribution HR [SHR], .99; 95% CI, .80-1.22; P = .926). Propensity score matching was used, and 733 diffuse types were matched with 733 intestinal types. We did not find any association between the Lauren type and LNM (odds ratio, .98; 95% CI, .71-1.37; P = .934) or prognosis in the univariate Cox regression (HR, .98; 95% CI, .76-1.26; P = .893) and univariate competing risk model (SHR, .98; 95% CI, .76-1.26; P = .893).

CONCLUSIONS

Diffuse-type EGC may have a comparable risk of LNM and prognosis to intestinal-type EGC. Nevertheless, these results should be carefully interpreted with caution when choosing endoscopic resection instead of surgery, because the treatment choice for EGC depends on the risk of lymphovascular invasion rather than LNM rate or prognosis.

Prognostic Significance of Solitary Lymphnode Metastasis and Micrometastasis in Gastric Cancer

Gastric cancer (GC) used to be one of the most common malignancies in the world and still is the second leading cause of malignancy-related death in the Far East. The most significant factors that were found to be associated with the clinical outcome in patients with non-metastatic (M₀) gastric cancer is tumor's depth of invasion, the presence and the extend of lymphnode involvement, as well as the histological type according to Lauren (intestinal or diffuse). Although it is generally accepted that D2 gastrectomy is the procedure of choice to achieve adequate oncologic excision, there are quite many concerns for its use in patients with early gastric cancer (EGC), where N_o or N₁ specimens are frequently reported. The last two decades, with the evolvement of cancer cell detection techniques, the attend of the medical community is focused on GC patients with solitary lymphnode metastasis (SLN) or micrometastasis (mM). There is a discussion whether SLN should be attributed as the “real” sentinel node (SN) and its projection on patients' survival. The aim of this study is to review the recent literature and attempt to clarify the clinical significance of SLN in gastric cancer.

The Characteristics and Prognosis of Diffuse-Type Early Gastric Cancer Diagnosed during Health Check-Ups

Background/Aims

Because of the poor prognosis of diffuse-type gastric cancer, early detection is important. We investigated the clinical characteristics and prognosis of diffuse-type early gastric cancer (EGC) diagnosed in subjects during health check-ups.

Methods

Among 121,111 subjects who underwent gastroscopy during a routine health check-up, we identified 282 patients with 286 EGC lesions and reviewed their clinical and tumor-specific parameters.

Results

Patients with diffuse-type EGC were younger, and 48.1% of them were female. Serum anti-Helicobacter pylori IgG (Hp-IgG) was positive in 90.7% of diffuse-type EGC patients (vs 75.9% of intestinal-type EGC, p=0.002), and the proportion of diffuse-type EGC cases increased significantly with increasing Hp-IgG serum titers (p<0.001). Diffuse-type EGC had pale discolorations on the tumor surface (26.4% vs 4.0% in intestinal-type EGC, p<0.001) and were often located in the middle third of the stomach. Submucosal invasion or regional nodal metastasis was observed more commonly in patients with diffuse-type EGC. However, during the median follow-up period of 50 months, 5-year disease-free survival rates did not differ between the groups.

Conclusions

Diffuse-type EGC shows different clinical and endoscopic characteristics. Diffuse-type EGC is more closely associated with Hp-IgG seropositivity and a higher serum titer. Early detection results in excellent prognosis.

Long non coding RNA XIST as a prognostic cancer marker - A meta-analysis

BACKGROUND

The X inactivate-specific transcript (XIST), derived from XIST gene, is aberrantly expressed in various cancers. High-expression of XIST is related to poor clinical outcome. This meta-analysis evaluated the potential role of XIST as novel predictor of prognosis in human cancer.

MATERIALS AND METHODS

This meta-analysis collected eligible studies about XIST and tumor prognosis through retrieving keywords in Web of Science, PubMed, Embase and the CNKI database, from 1993 to August 21, 2017. The quantitative meta-analysis was carried out with Stata SE12.0 and RevMan3.23 software. The aim was to determine whether XIST expression is associated with cancer prognosis and clinicopathology.

RESULTS

A total of 858 patients from 10 eligible studies were included in the final meta-analysis. Overall, a significant negative association between XIST and overall survival (OS) time (HR = 2.62, 95% CI: 2.18-3.14) was observed. Statistical significance was also showed in subgroup meta-analysis stratified by the country, sample size, follow-up and publication year. It was reported that increased XIST was positively related to advanced clinical TNM stage (OR = 4.03, 95% CI: 2.22-7.30), lymph node metastasis (LNM) (OR = 2.70, 95% CI: 1.73-4.21), distant metastasis (DM) (OR = 2.61, 95% CI: 1.57-4.33) and tumor size (OR = 3.10, 95% CI: 2.24-4.30).

CONCLUSIONS

LncRNA XIST may serve as a potential biomarker to predict solid tumor prognosis. This molecule can be effectively used to predict the clinical and pathological features of cancers.

Construction and external validation of a nomogram that predicts lymph node metastasis in early gastric cancer patients using preoperative parameters

Objective

To create a nomogram to predict the incidence of lymph node metastasis (LNM) in early gastric cancer (EGC) patients and to externally validate the nomogram.

Methods

To construct the nomogram, we retrospectively analyzed a primary cohort of 272 EGC patients. Univariate analysis and a binary logistic regression were performed. A nomogram predicting the incidence of LNM in EGC patients was created. The discrimination ability of the nomogram was measured using the concordance index (c-index), and the nomogram was also calibrated. Then, another prospective cohort of 81 patients was analyzed to validate the nomogram.

Results

In the primary cohort, LNM was pathologically confirmed in 37 (13.6%) patients. In multivariate analysis, the presence of an ulcer, the maximum lesion diameter observed via gastroscopy, the thickness of the lesion observed via endoscopic ultrasonography, and the presence of enlarged lymph nodes on computed tomography (CT) were independent risk factors for LNM. A nomogram was then created based on the regression model with the c-index of 0.905, and the calibration curve of the nomogram fell approximately on the ideal 45-degree line. The cut-off score of the nomogram was 110, and the sensitivity, specificity, positive predictive and negative predictive values of the nomogram in the primary cohort were 81.1%, 86.0%, 47.6% and 96.7%, respectively, and in the prospective validation cohort were 75.0%, 91.0%, 60.0% and 95.5%, respectively. The calibration curve of the external validation cohort was almost on the 45-degree line.

Conclusions

We developed an effective nomogram predicting the incidence of LNM for EGC patients.

Long-term outcomes of endoscopic submucosal dissection in comparison to surgery in undifferentiated-type intramucosal gastric cancer using propensity score analysis

BACKGROUND

The treatment of intramucosal early gastric cancer with undifferentiated-type histologies (UD-EGCs) using endoscopic submucosal dissection (ESD) is controversial. This study aimed to compare the clinical and oncologic long-term outcomes of ESD and surgery for UD-EGCs.

METHODS

A prospectively collected database of patients who underwent ESD or surgery between January 2006 and December 2012 was established. Patients who diagnosed with UD-EGC and satisfied the expanded indications of ESD were included. Clinical data from 111 patients treated with ESD and 382 patients underwent surgery were analyzed, and 1-1 propensity score-matched 81 pairs of patients were also compared.

RESULTS

In both groups, two-thirds of the UD-EGCs had signet ring cell (SRC)-type histology and about 90% of UD-EGCs were flat or depressed types. The mean size of tumors was smaller in ESD group (9.7 vs. 13.2 mm; P < 0.001). After propensity score-matched, case-matching covariates were not significantly different between the groups. Disease-free survival (DFS) was significantly shorter in the ESD group, but overall survival (OS) was not different between the two groups both in overall comparison (DFS; P < 0.001 and OS; P = 0.078) and propensity score-matched analysis (DFS; P < 0.001 and OS; P = 0.850). According to histologic type, OS of SRC histology was not different between the group, both in overall comparison and propensity score-matched analysis (P = 0.286 and P = 0.210). On the other hands, OS of poorly differentiated adenocarcinoma was significantly shorter in ESD group in overall comparison (P = 0.007), but was not as so in propensity score-matched analysis (P = 0.088).

CONCLUSIONS

ESD might be a complementary option for the treatment of UD-EGCs, especially in those with SRC-type histology based on strict expanded indications. Nonetheless, close endoscopic surveillance is required because of a high incidence of intragastric recurrence.

Current status of lymph node micrometastasis in gastric cancer

Lymph node metastasis is one of the most important prognostic factors in patients with gastric cancer. An inadequate number of dissected lymph nodes is an independent risk factor affecting recurrence, even in patients who are node negative. Oddly, certain early-stage patients still experience recurrence or metastasis within a short time, even if they have undergone standard radical mastectomy. Many researchers have attributed these adverse events to lymph node micrometastasis (LNM), which is defined as a microscopic deposit of malignant cells of less than 2 mm in diameter. With the development of diagnostic tools such as immunohistochemistry and reverse transcription-polymerase chain reaction, the rate of detection of LNM has been constantly increasing. Although there is no clear consensus about risk factors for or the definitive clinical significance of LNM, the clinical impact of LNM is remarkable in gastric cancer. For minimally invasive treatment in particular, such as endoscopic submucosal dissection and laparoscopic surgery, accurate diagnosis of LNM is regarded as the potential key to maintaining the balance between curability and safety. This review provides an overview of the definition, detection and significance of LNM in gastric cancer. We also summarize several attention-drawing controversies regarding the treatment of patients who may have LNM.

Predictive Factors for Lymph Node Metastasis in Undifferentiated Early Gastric Cancer: a Systematic Review and Meta-analysis

OBJECTIVES

Less invasive surgery is gaining popularity for the treatment of early gastric cancer (EGC), but there are no definitive guidelines for the use of less invasive surgery for the treatment of undifferentiated EGC. The aims of this meta-analysis were to identify potential predictive factors for lymph node metastasis (LNM) in undifferentiated EGC and to guide the personalized therapeutic modality for patients with undifferentiated EGC.

METHODS

An extensive search of the PubMed, Embase, and Cochrane Library databases was performed to identify relevant articles involving undifferentiated EGC and LNM. Eligible data were systematically reviewed through a meta-analysis using Review Manager 5.3.

RESULTS

In total, 23 studies were included in this analysis. The meta-analysis found that the variables sex (female), age (greater than 60 years), tumor size (greater than 20 mm), depth of invasion (submucosal invasion), presence of lymphovascular involvement, presence of ulcer findings, histology type (non-signet ring carcinoma), and tumor location (not in the middle part of the stomach) were significantly associated with LNM.

CONCLUSIONS

Eight variables were identified as predictive factors for LNM in undifferentiated EGC. The significance of these variables should be further confirmed during the process of LNM in undifferentiated EGC patients for future clinical application.

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.

Clinical prognostic significance of regional and extended lymphadenectomy for biliary cancer with para-aortic lymph node metastasis: A systematic review and meta-analysis

BACKGROUND

The aim of our study was to evaluate clinical prognostic significance of regional and extended lymphadenectomy for biliary cancer with para-aortic lymph node metastasis.

METHODS

A thorough literature search was performed in PubMed/Medline, Cochrane Central Register, Embase, ISI Web of Science and Google Scholar between January 1965 and May 2014 with restricted articles for the English language. Data were processed for a meta-analysis by RevMan 5 software.

RESULTS

Altogether 10 retrospective studies were finally enrolled in our study. For positive para-aortic lymph node group irrespective of regional lymph node metastasis, the overall 1-, 3-, 5-yr pooled RR estimates of survival rates were 2.30, 1.70, and 1.42. There were significant differences between positive para-aortic lymph node group and negative group. For positive para-aortic lymph node group in the setting of regional lymph node metastasis, the overall 1-, 3-, 5-yr pooled RR estimates of survival rates were 1.57, 1.29, and 1.11, respectively. The long-term outcomes referred to 5-yr survival rate were similar between para-aortic lymph node metastasis and regional lymph node metastasis only.

DISCUSSION

Radical resection with extended lymphadenectomy should be caution in terms of the results of an intraoperative sampling biopsy of para-aortic lymph node, which requires a well-designed, prospective controlled study in the future.

Long Noncoding RNA MALAT-1 Can Predict Metastasis and a Poor Prognosis: a Meta-Analysis

Elevated expression of MALAT-1 was found in various cancers, and correlated with metastasis and prognostic. This meta-analysis collected all relevant articles and explored correlation of MALAT-1 with lymph node metastasis (LNM), distant metastasis (DM), and overall survival (OS). A quantitative meta-analysis was performed through a systematic search in PubMed, Web of Science, Medline, CNKI, CBM, and the Cochrane Library. The odds ratios (OR) of LNM and DM and hazard ratio (HR) of OS were calculated to assess the association strength. Eight studies with a total of 845 patients were included in the meta-analysis. Six different types of cancer were evaluated, with 2 non-small cell lung cancer (NSCLC), 1 colorectal cancer (CRC), 1 gastric cancer (GC), 2 pancreatic cancer (PC), 1 clear cell renal cell carcinoma (ccRCC), and 1 osteosarcoma (OSA). Compared with low MALAT-1 expression, high MALAT-1 expression correlated with more LNM (OR = 2.08, 95 %CI: 1.00-4.32, p = 0.05) by a random-effects model (I (2) = 71 %, p = 0.004). A similar result was seen between MALAT-1 expression and DM, the OR was 3.52 (95 %CI: 1.06-11.71, p = 0.04) adopting a random-effects model (I (2) = 59 %, p = 0.04). Additionally, our analysis showed a poorer OS in patients with high MALAT-1 expression than those with low MALAT-1 expression (HR = 2.12, 95 %CI: 1.60-2.82, p < 0.001) adopting a random-effects model (I (2) = 56 %, p = 0.04). MALAT-1 may serve as a molecular marker for cancer metastasis and prognosis.

Endoscopic submucosal dissection for early gastric cancer with undifferentiated-type histology: A meta-analysis

AIM: To evaluate the efficacy and safety of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) with undifferentiated-type histology.

METHODS: A systematic literature review was conducted using the core databases. Complete resection, curative resection, en bloc resection, recurrence and adverse event rate were extracted and analyzed. A random effect model was applied. The methodological quality of the enrolled studies was assessed using the Newcastle-Ottawa Scale. Publication bias was evaluated using a funnel plot, the trim and fill method, Egger’s test, and a rank correlation test.

RESULTS: Fourteen retrospective studies between 2009 and 2014 were identified (972 EGC lesions with undifferentiated-type histology). The total en bloc and complete resection rates were estimated as 92.1% (95%CI: 87.4%-95.2%) and 77.5% (95%CI: 69.3%-84%), respectively. The total curative resection rate was 61.4% (95%CI: 44.5%-75.9%). The overall recurrence rate was 7.6% (95%CI: 3.4%-16%). Limited to histologically diagnosed expanded-criteria lesions, the en bloc and complete resection rates were 91.2% and 85.6%, respectively. The curative resection rate was 79.8%.

CONCLUSION: In this analysis, ESD is a technically feasible treatment modality for EGC with undifferentiated-type histology. Long-term studies are needed to confirm these therapeutic outcomes.