Risk factors of lymph node metastasis after non-curative endoscopic resection of undifferentiated-type early gastric cancer

The Key Role of Tumor Budding in Predicting the Status of Lymph Node Involvement in Early Gastric Cancer Patients: A Clinical Multicenter Validation in China

BACKGROUND

Accurate preoperative prediction of lymph node (LN) involvement is essential for the management of early gastric cancer (EGC). Our objective was to formulate a potent nomogram for predicting LN involvement in EGC by leveraging an innovative predictor of tumor budding.

METHODS

We assembled a cohort of EGC patients who underwent radical surgery at two tertiary cancer centers. Tumor budding was stratified by using an optimal cutoff value and integrated with other clinicopathological variables to ascertain the risk factors associated with LN involvement. A nomogram was developed and its predictive performance was assessed by using receiver operating characteristic (ROC) curves and calibration plots. In addition, we conducted decision curve analysis to evaluate its clinical utility. Finally, an external validation was conducted by using an independent cohort.

RESULTS

Finally, 307 eligible patients (215 in the primary cohort and 92 in the validation cohort) were included. Tumor budding, categorized by a count of two, exhibited a robust association with LN involvement (OR 14.12, p = 0.012). Other significant risk factors include lymphovascular invasion, depth of tumor invasion, ulceration, and tumor differentiation. Notably, the nomogram demonstrated exceptional discriminative power (area under the ROC curve, 0.872 in the primary cohort and 0.885 in the validation cohort) and precise predictive capabilities. Furthermore, the nomogram showed notable clinical applicability through decision curve analysis, particularly in endoscopic curability C-2, by mitigating the risk of overtreatment.

CONCLUSIONS

Tumor budding is a robust predictor of LN involvement in EGC. The incorporation of tumor budding into a nomogram is an effective strategy, thereby informing and enhancing clinical decision-making.

Clinicopathologic factors correlated with lymph node metastasis in gastric cancer: a retrospective cohort study involving 5606 patients

BACKGROUND

The identification of risk factors associated with lymph node metastasis (LNM) in gastric cancer will establish a crucial foundation for the implementation of endoscopic operation and multidisciplinary treatment programs.

METHODS

A total of 5606 patients with gastric cancer with comprehensive clinicopathologic data were enrolled through systematic searching and rigorous screening. Of the 5606 patients, 1438 were diagnosed with early gastric cancer (EGC), which would be used for further analysis. Subsequently, univariate and multivariate logistic regression analyses were performed to identify the risk factors.

RESULTS

The rates of LNM in T1a, T1b, T2, T3, T4a, and T4b stage gastric cancer were 7.0%, 19.4%, 48.4%, 77.1%, 83.8%, and 89.6%, respectively. Female (odds ratio [OR], 1.559; P = .032), lower tumor location (OR, 1.773; P = .023), tumor size of >2 cm (OR, 2.007; P < .001), mixed (OR, 2.371; P = .001) and undifferentiated histologic types (OR, 2.952; P < .001), T1b stage (OR, 2.041; P < .001), presence of ulceration (OR, 1.758; P = .027), and lymphovascular invasion (OR, 5.722; P < .001) were identified as independent risk factors for LNM in EGC. A nomogram was constructed using appropriate predictors to preoperatively predict the risk of LNM in patients with EGC.

CONCLUSION

This study identified the clinicopathologic factors associated with LNM in patients with EGC and developed a prediction model, thereby facilitating the integration of diverse treatment modalities in managing patients with EGC.

Sentinel Node Navigation Surgery for Early Gastric Cancer: A Narrative Review

Early gastric cancer (EGC) refers to malignant tumor lesions that are limited to the mucosa and submucosa layers, regardless of the presence of lymph node metastasis. Typically, EGC has a low rate of perigastric lymph node metastasis, and long-term survival outcomes are good after radical surgical treatment. The primary objective of surgical treatment for EGC is to achieve functional preservation while ensuring a radical cure. Sentinel node navigation surgery (SNNS) is a surgical technique used in the treatment of EGC. This approach achieves functional preservation by limiting lymph node dissection and performing restrictive gastrectomy guided by intraoperative negative sentinel node (SN) biopsy. Despite the apparent improvement in the detection rate of SN with the emergence of various tracing dyes and laparoscopic fluorescence systems, the oncological safety of SNNS remains a controversial research topic. SNNS, as a true form of stomach preservation surgery that enhances the quality of life, has become a topic of interest in the EGC field. In recent years, scholars from Japan and South Korea have conducted extensive research on the feasibility and safety of SNNS in the treatment of EGC. This article aims to provide reference choices for surgeons treating EGC by reviewing relevant research on SNNS for EGC in recent years.

A Modified eCura System to Stratify the Risk of Lymph Node Metastasis in Undifferentiated-Type Early Gastric Cancer After Endoscopic Resection

PURPOSE

The original eCura system was designed to stratify the risk of lymph node metastasis (LNM) after endoscopic resection (ER) in patients with early gastric cancer (EGC). We assessed the effectiveness of a modified eCura system for reflecting the characteristics of undifferentiated-type (UD)-EGC.

MATERIALS AND METHODS

Six hundred thirty-four patients who underwent non-curative ER for UD-EGC and received either additional surgery (radical surgery group; n=270) or no further treatment (no additional treatment group; n=364) from 18 institutions between 2005 and 2015 were retrospectively included in this study. The eCuraU system assigned 1 point each for tumors >20 mm in size, ulceration, positive vertical margin, and submucosal invasion <500 µm; 2 points for submucosal invasion ≥500 µm; and 3 points for lymphovascular invasion.

RESULTS

LNM rates in the radical surgery group were 1.1%, 5.4%, and 13.3% for the low- (0-1 point), intermediate- (2-3 points), and high-risk (4-8 points), respectively (P-for-trend<0.001). The eCuraU system showed a significantly higher probability of identifying patients with LNM as high-risk than the eCura system (66.7% vs. 22.2%; McNemar P<0.001). In the no additional treatment group, overall survival (93.4%, 87.2%, and 67.6% at 5 years) and cancer-specific survival (99.6%, 98.9%, and 92.9% at 5 years) differed significantly among the low-, intermediate-, and high-risk categories, respectively (both P<0.001). In the high-risk category, surgery outperformed no treatment in terms of overall mortality (hazard ratio, 3.26; P=0.015).

CONCLUSIONS

The eCuraU system stratified the risk of LNM in patients with UD-EGC after ER. It is strongly recommended that high-risk patients undergo additional surgery.

Decision to perform additional surgery after non-curative endoscopic submucosal dissection for gastric cancer based on the risk of lymph node metastasis: a long-term follow-up study

BACKGROUND

Radical surgery after non-curative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) may be excessive, since only 5-10% of patients have lymph node metastasis (LNM). This study investigated the suitability of the eCura system for determining the need for radical surgery after non-curative ESD.

METHODS

We retrospectively investigated 343 patients who underwent non-curative ESD for EGC from 2006 to 2021 at a tertiary hospital in Korea. These patients were divided into surgery (n = 191) and observation (n = 152) groups based on whether they underwent additional surgery post-ESD. Each group was further classified into low-risk (eCura score 0-1), intermediate-risk (eCura score 2-4) and high-risk (eCura score 5-7). All patients were regularly followed-up at least annually after the initial treatment. The cumulative overall and recurrence-free survival rates were calculated for each category and compared between the surgery and observation groups.

RESULTS

No significant differences in overall survival were found between the surgery and observation groups in low-risk (p = 0.168) and intermediate-risk patients (p = 0.306); however, high-risk patients had better 5-year overall survival rate in the surgery group than in the follow-up group (95.2% vs. 71.4%, p < 0.001). The 5-year recurrence-free survival rate was higher in the surgery group than in the observation group for low-risk (100% vs. 84.3%; p = 0.034), intermediate-risk (96.1% vs. 88.4%; p = 0.081) and high-risk patients (100% vs. 83.3%; p = 0.023).

CONCLUSIONS

Follow-up without additional surgery after non-curative ESD can be a reasonable option for low-risk and even intermediate-risk patients according to the eCura system. However, surgery is warranted for eCura high-risk patients.

A nomogram for predicting lymph node metastasis in early gastric signet ring cell carcinoma

At present, the risk factors for lymph node metastasis in early gastric signet ring cell carcinoma (SRCC) remain unclear. However, it is worth noting that the LNM rate and prognosis of early gastric SRCC are superior to those of other undifferentiated cancers. With advancements in endoscopic technology, the 5-year survival rate following endoscopic treatment of early gastric cancer is comparable to traditional surgery while offering a better quality of life. The objective of this study was to develop a nomogram that can predict lymph node status in early gastric SRCC before surgery, aiding clinicians in selecting the optimal treatment strategy. A research cohort was established by retrospectively collecting data from 183 patients with early gastric SRCC who underwent radical gastrectomy with lymph node dissection at our hospital between January 2014 and June 2022. The predictors of early gastric signet ring cell carcinoma lymph node metastasis were identified in the study cohort using the least absolute selection and shrinkage operator (Lasso) and multivariate regression analysis, and a nomogram was developed. The discrimination, accuracy, and clinical practicability of the nomogram were assessed using receiver operating characteristic (ROC) curve analysis, calibration curve analysis, and decision curve analysis. The incidence of lymph node metastasis was 21.9% (40/183) overall. Multivariate logistic regression analysis revealed that tumor size and lymphovascular invasion (LVI) were independent risk factors for lymph node metastasis. Lasso regression analysis demonstrated that tumor size, invasion depth, LVI, E-cadherin expression, dMMR, CA242, NLR, and macroscopic type were associated with lymph node metastasis. The integrated discrimination improvement (IDI) (P = 0.034) and net reclassification index (NRI) (P = 0.023) were significantly improved when dMMR was added to model 1. In addition, the area under curve (AUC) (P = 0.010), IDI (P = 0.001) and NRI (P < 0.001) of the model were significantly improved when type_1 was included. Therefore, we finally included tumor size, invasion depth, dMMR, and macroscopic type to establish a nomogram, which had good discrimination (AUC = 0.757, 95% CI 0.687-0.828) and calibration. Decision curve analysis showed that the nomogram had good clinical performance. We have developed a risk prediction model for early gastric signet ring cell carcinoma that accurately predicts lymph node involvement, providing clinicians with a valuable tool to aid in patient counseling and treatment decision-making.

External Validation of the eCura System for Undifferentiated-Type Early Gastric Cancer with Noncurative Endoscopic Resection

Background/Aims

The eCura system, a scoring model for stratifying the lymph node metastasis risk after noncurative endoscopic resection for early gastric cancer (EGC), has been internally validated, primarily for differentiated-type EGC. We aimed to externally validate this model for undifferentiated-type EGC.

Methods

This multicenter, retrospective cohort study included 634 patients who underwent additional surgery (radical surgery group, n=270) or were followed up without additional treatment (no additional treatment group, n=364) after noncurative endoscopic resection for undifferentiated-type EGC between 2005 and 2015. The lymph node metastasis and survival rates were compared according to the risk categories.

Results

For the radical surgery group, the lymph node metastasis rates were 2.6%, 10.9%, and 14.8% for the low-, intermediate-, and high-risk eCura categories, respectively (p for trend=0.003). For the low-, intermediate-, and high-risk categories in the no additional treatment group, the overall survival (92.7%, 68.9%, and 80.0% at 5 years, respectively, p<0.001) and cancer-specific survival rates (99.7%, 94.7%, and 80.0% at 5 years, respectively, p<0.001) differed significantly. In the multivariate analysis, the hazard ratios (95% confidence interval) in the no additional treatment group relative to the radical surgery group were 3.18 (1.41 to 7.17; p=0.005) for overall mortality and 2.60 (0.46 to 14.66; p=0.280) for cancer-specific mortality in the intermediate-to-high risk category. No such differences were noted in the low-risk category.

Conclusions

The eCura system can be applied to undifferentiated-type EGC. Close follow-up without additional treatment might be considered for low-risk patients, while additional surgery is recommended for intermediate- and high-risk patients.

Long-term outcomes of additional surgery versus non-gastrectomy treatment for early gastric cancer after non-curative endoscopic submucosal dissection: a meta-analysis

BACKGROUND

Endoscopic resection is increasingly used in the treatment for early gastric cancer (EGC); however, about 15% of endoscopic submucosal dissection (ESD) cases report non-curative resection. The efficacy of different remedial interventions after non-curative ESD for EGC remains controversial. This meta-analysis aimed to compare the long-term outcomes of additional surgery and non-gastrectomy treatment for EGC patients who underwent non-curative ESD.

METHODS

All relevant studies published up to October 2021 were systematically searched in the PubMed, Web of Science, and Embase databases. The medical subject headings terms "early gastric cancer," "gastrectomy," "endoscopic submucosal dissection," and their related free keywords were used to search relevant articles without restrictions on regions, publication types, or languages. The Newcastle-Ottawa Quality Assessment Scale was used to evaluate the quality of the included studies. Odds ratios (ORs) with 95% confidence intervals (CIs) of 5-year overall survival (OS), disease-specific survival (DSS), disease-free survival (DFS) and hazard ratios (HRs) with 95% CIs of OS were calculated using a random- or fixed-effects model.

RESULTS

This meta-analysis included 17 retrospective cohort studies with 5880 patients, of whom 3167 underwent additional surgery and 2713 underwent non-gastrectomy. We found that patients receiving additional gastrectomy had better 5-year OS (OR = 3.63, 95% CI = 3.05-4.31), DSS (OR = 3.22, 95% CI = 2.22-4.66), and DFS (OR = 4.39, 95% CI = 1.78-10.82) outcomes than those receiving non-gastrectomy treatments. The pooled HR also showed that gastrectomy following non-curative ESD significantly improved OS (HR = 0.40, 95% CI = 0.33-0.48). In addition, elderly patients benefited from additional surgery in consideration of the 5-year OS (HR = 0.54, 95% CI = 0.41-0.72).

CONCLUSIONS

Compared with non-gastrectomy treatments, additional surgery offered better long-term survival outcomes for patients with EGC who underwent non-curative ESD.

Construction of a nomogram for preoperative prediction of the risk of lymph node metastasis in early gastric cancer

Background

The status of lymph node metastasis (LNM) in patients with early gastric cancer (EGC) is particularly important for the formulation of clinical treatment. The purpose of this study was to construct a nomogram to predict the risk of LNM in EGC before operation.

Methods

Univariate analysis and logistic regression analysis were used to determine the independent risk factors for LNM. The independent risk factors were included in the nomogram, and the prediction accuracy, discriminant ability and clinical practicability of the nomogram were evaluated by the receiver operating characteristic curve (ROC), calibration curve and clinical decision curve (DCA), and 100 times ten-fold cross-validation was used for internal validation.

Results

33 (11.3%) cases of AGC were pathologically confirmed as LNM. In multivariate analysis, T stage, presence of enlarged lymph nodes on CT examination, carbohydrate antigen 199 (CA199), undifferentiated histological type and systemic inflammatory response index (SIRI) were risk factors for LNM. The area under the ROC curve of the nomogram was 0.86, the average area under the ROC curve of the 100-fold ten-fold cross-validation was 0.85, and the P value of the Hosmer-Lemeshow test was 0.60. In addition, the clinical decision curve, net reclassification index (NRI) and Integrated Discriminant Improvement Index (IDI) showed that the nomogram had good clinical utility.

Conclusions

We found that SIRI is a novel biomarker for preoperative prediction of LNM in EGC, and constructed a nomogram for preoperative prediction of the risk of LNM in EGC, which is helpful for the formulation of the clinical treatment strategies.

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.

Risk of Lymph Node Metastasis and Feasibility of Endoscopic Treatment in Ulcerative Early Gastric Cancer

BACKGROUND

When the risk of lymph node metastasis (LNM) is considered minimal in patients with early gastric cancer (EGC), endoscopic submucosal dissection (ESD) is an effective alternative to radical resection. This study aims to estimate the feasibility of ESD for EGC with ulceration.

PATIENTS AND METHODS

We retrospectively reviewed data from 691 patients who underwent gastrectomy for EGC with ulceration. Subsequently, a stratification system for lesions was created based on the expanded ESD criteria, and the associations between the subgroups and the rate of LNM were analyzed.

RESULTS

LNM was confirmed in 16.5% (114/691) of patients. Univariate analysis demonstrated that age, sex, tumor size, macroscopic features, depth of invasion, tumor differentiation, Lauren type, lymphovascular invasion (LVI), and perineural invasion were associated with LNM. Multivariate analysis showed that LVI [odds ratio (OR) = 16.761, P < 0.001], SM1 invasion (OR = 2.159, P = 0.028), and SM2 invasion (OR = 3.230, P < 0.001) were independent risk factors for LNM. LNM occurred in undifferentiated mucosal tumors, with ulceration being 1.7% (2/116) when the lesion was smaller than 20 mm. Further stratification revealed that among lesions < 30 mm in size, undifferentiated tumors with SM1 invasion had a higher rate of LNM and a lower disease-free survival rate than differentiated tumors with SM1 invasion and tumors limited to the mucosal layer.

CONCLUSIONS

Depth of invasion and LVI were strongly associated with LNM in ulcerative EGC. Endoscopic resection may be applicable for undifferentiated mucosal ulcerative EGC < 30 mm in size, and additional investigation is needed to evaluate its safety.