Tumour size is related to the curability of signet ring cell early gastric cancer with endoscopic submucosal dissection: a retrospective single centre study

Risk of lymph node metastasis and feasibility of endoscopic submucosal dissection in undifferentiated-type early gastric cancer

BACKGROUND

Whether endoscopic submucosal dissection (ESD) applies to undifferentiated-type early gastric cancer (UEGC) remains controversial. We aimed to analyze the risk factors for lymph node metastasis (LNM) in UEGC and evaluate the feasibility of ESD.

METHODS

This study included 346 patients with UEGC who underwent curative gastrectomy between January 2014 and December 2021. Univariate and multivariate analyses of the correlation between clinicopathological features and LNM were conducted, and the risk factors for exceeding the expanded ESD indications were evaluated.

RESULTS

The overall LNM rate in UEGC was 19.94%. Among the preoperatively assessable factors, submucosal invasion (odds ratio [OR] = 4.77, 95% confidence interval [CI]: 2.14-10.66) and > 2 cm(OR = 2.49, 95% CI: 1.20-5.15) were independent risk factors for LNM, while postoperative independent risk factors were > 2 cm (OR = 3.35, 95% CI: 1.02-5.40) and lymphovascular invasion(OR = 13.21, 95% CI: 5.18-33.70). Patients who met the expanded indications had a low LNM risk (4.1%). Additionally, tumors located in the cardia (P = 0.03), non-elevated type (P < 0.01) were independent risk factors for exceeding the expanded indications in UEGC.

CONCLUSIONS

ESD may be applicable for UEGC meeting the expanded indications, and preoperative evaluation should be cautious when the lesion is non-elevated type or located in the cardia.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (12/05/2022 ChiCTR2200059841 ).

Update on diagnosis and treatment of early signet-ring cell gastric carcinoma: A literature review

Gastric signet-ring cell gastric carcinoma (GSRC) is an unfavorable subtype of gastric cancer (GC) that presents with greater invasiveness and poorer prognosis in advanced stage than other types of GC. However, GSRC in early stage is often considered an indicator of less lymph node metastasis and more satisfying clinical outcome compared to poorly differentiated GC. Therefore, the detection and diagnosis of GSRC at early stage undoubtedly play a crucial role in the management of GSRC patients. In recent years, technological advancement in endoscopy including narrow-band imaging and magnifying endoscopy has significantly improved the accuracy and sensitivity of the diagnosis under endoscopy for GSRC patients. Researches have confirmed that early stage GSRC that meets the expanded criteria of endoscopic resection showed comparable outcomes to surgery after receiving endoscopic submucosal dissection (ESD), indicating that ESD could be considered standard treatment for GSRC after thorough selection and evaluation. This article summarizes the current knowledge and updates pertaining to the endoscopic diagnosis and treatment of early stage signet-ring cell gastric carcinoma.

Efficacy and safety of pocket-creation method for early gastric cancers

BACKGROUND

Endoscopic submucosal dissection (ESD) is the standard endoscopic treatment for early gastric cancers (EGCs). However, obscured view and difficulty in submucosal lifting during ESD have been demonstrated. Additionally, ESD is time-consuming and poses a high risk of perforation and bleeding when performed in challenging locations. The pocket-creation method (PCM) is a newly developed strategy for colorectal tumors, while the outcomes of application in the treatment of EGCs are rarely reported. In the present study, we aimed to compare the technical efficacy and safety of PCM-ESD and the conventional ESD (c-ESD) technique for the treatment of EGCs.

METHODS

This was a single-center retrospective study consisting of 162 patients with EGCs who underwent ESD between February 2019 and February 2021. One-to-one propensity score matching (PSM) was performed. In addition, clinicopathological characteristics and treatment outcomes were also compared.

RESULTS

PCM-ESD was more likely to be used in patients with larger lesions than c-ESD with/without traction. In addition, the resection speed for lesions of the PCM-ESD was faster compared with c-ESD without traction (median dissection speed: 19.6 mm²/min vs. 15 mm²/min; p < 0.001) and c-ESD with traction (median dissection speed after PSM: 19.9 mm²/min vs. 15 mm²/min; p = 0.001). In multiple linear regression analysis, significant factors related to a higher dissection speed were the treatment method of PCM-ESD (p = 0.034), the long diameter of the resected lesion (p = 0.001), and lesion location (p = 0.046).

CONCLUSIONS

Collectively, PCM-ESD appeared to be a safer and more effective treatment for EGCs than c-ESD. In addition, PCM-ESD could significantly improve the speed of tumor resection.

Endoscopic submucosal dissection for early signet ring cell gastric cancer: A systematic review and meta-analysis

BACKGROUND

The use of endoscopic submucosal dissection (ESD) for treating early signet ring cell carcinoma (SRC) is controversial due to the risk of lymph node metastasis.

AIM

To carry out a meta-analysis to evaluate ESD for therapeutic efficacy and safety in early signet ring cell gastric cancer.

METHODS

The PubMed, Web of Science, Cochrane Library, and EMBASE databases were used to search for relevant studies evaluating the therapeutic efficacy and safety of ESD in SRC. The rates of recurrence, complete resection, incomplete resection, curative resection, en bloc resection, and adverse events were extracted and analyzed. The methodological quality of the enrolled studies was assessed using the Newcastle-Ottawa Scale. Publication bias was evaluated by the Egger’s test. Institutional review board approval and written consent were not needed for this report.

RESULTS

This meta-analysis enrolled seven studies with 653 participants undergoing ESD treatment for early SRC. The overall recurrence rate was 0.010 [95% confidence interval (CI): 0.000-0.040, Z = 1.422, P = 0.155]. The total lymphovascular invasion rate was 0.038 (95%CI: 0.007-0.088, Z = 3.026, P = 0.002). The total en bloc resection rate was estimated at 0.984 (95%CI: 0.925-1.000, Z = 19.463, P = 0.000). The total complete and incomplete resection rates were estimated at 0.785 (95%CI: 0.596-0.928, Z = 9.789, P = 0.000) and 0.188 (95%CI: 0.016-0.468, Z = 2.531, P = 0.011), respectively. The total procedure-associated gastric hemorrhage and perforation rates were estimated at 0.026 (95%CI: 0.005-0.061, Z = 3.006 P = 0.003) and 0.004 (95%CI: 0.000-0.028, Z = 0.938, P = 0.348), respectively. The curative resection, vertical margin invasion, and lateral margin invasion rates were 72.1% (145/341), 2.3% (8/348), and 34.45% (41/119), respectively.

CONCLUSION

ESD constitutes a promising therapeutic approach for early undifferentiated SRC gastric cancer. However, further improvements are required for increasing its treatment efficacy and reducing adverse outcomes.

Prevalence of Regional Lymph Node Metastasis of Mucosal Gastric Signet Ring Cell Carcinoma: Analysis of the Collaborative Stage Data Survey of the Korean Central Cancer Registry

INTRODUCTION

Patients with very early-stage gastric signet ring cell carcinoma (SRC) are eligible for minimally invasive treatment, like endoscopic submucosal dissection. However, population-based data on regional lymph node metastasis (LNM) and distant metastasis of gastric SRC are lacking. This study aimed to identify the prevalence of LNM and distant metastasis in mucosal cancer (T1a) of gastric SRC.

METHODS

The Collaborative Stage Data Survey was performed by the Korean Center of Cancer Registry between 2010 and 2015 to establish collaborative stage data of the stomach, colon, rectum, rectosigmoid junction, and breast. From the survey data, information on patients with gastric SRC was extracted for analysis. Variables including age, sex, diagnosis date, primary site, tumor size, histology, American Joint Committee on Cancer staging system scores, and Surveillance, Epidemiology, and End Results summary stage were analyzed.

RESULTS

A total of 1,335 (65.7%) patients had mucosal gastric SRC, and 1,189 (89.1%) patients had surgery and 134 (10%) had endoscopic treatment. Of them, 1,283 (96.1%) patients did not have regional LNM, and 52 (3.9%) patients had regional LNM and 6 (0.4%) had distant metastasis. The hazard ratios of LNM and distant metastasis were 14.98 (95% CI: 4.18-53.2) and 10.09 (95% CI: 2.30-44.17).

CONCLUSIONS

Reginal LNM and distant metastasis occur very less in mucosal gastric SRC, but they are associated with an increased risk of cancer-related death. Even in early stage, surgery should be considered as a standard treatment of mucosal gastric SRC.

Laparoscopic Prophylactic Total Gastrectomy for Hereditary Diffuse Gastric Cancer in CDH1 Mutation Carriers

Background: Patients with hereditary diffuse gastric cancer (HDGC) and germline mutations in the E-cadherin gene, CDH1, have a very high cumulative lifetime risk of developing diffuse gastric cancer. In these patients, it is formally recommended to perform a prophylactic total gastrectomy (PTG). Materials and Methods: We analyzed the course of patients with HDGC who have undergone PTG in our institution. Pedigree analysis, preoperative screening results, operative course, postoperative data, and complete stomach pathologic examination were performed in all patients. Results: Seven patients with confirmed CDH1 mutation underwent PTG, five were women, and average age was 27 years (range 17-42). Signet ring cell carcinoma was found in 1 patient in the preoperative surveillance endoscopic biopsies. Laparoscopic PTG was performed in all patients. There were two complications, an intestinal obstruction that required reintervention and an asymptomatic esophagojejunal anastomosis leak that resolved with conservative treatment. In all gastrectomy specimens, intramucosal signet ring cell carcinoma foci limited to the lamina propria were found (range 1-31), 83.5% were in the body-fundus region. The mean follow-up was 28.5 months (range 8-72). The mean weight loss was 9% (range 2-18). Postoperative symptoms associated with Dumping syndrome were the most frequent. All the patients reported of being very satisfied with the procedure and of having a better quality of life than expected before the procedure. Conclusion: Laparoscopic PTG is an excellent resource to prevent the development of advanced diffuse gastric cancer (DGC) in patients with HDGC with CDH1 mutation. The procedure was well tolerated with a high satisfaction rate and very good functional results. It should be considered in these patients due to the high risk of developing advanced DGC and the lack of effective and reliable surveillance studies.

Gastric Signet Ring Cell Carcinoma: Current Management and Future Challenges

Recent advances in the epidemiology, pathology, molecular mechanisms, and combined modality therapy (CMT) fields have shown that gastric signet ring cell carcinoma (GSRC) should be considered a distinct cancerous entity. Clinical management of this cancer is challenging, with chemoradioresistance and poor outcomes in advanced stages. Pathological and molecular sets of GSRC demonstrate different features of poor cohesion and differentiation according to the WHO, Japanese Gastric Cancer Association, and Laurén classifications. These features also result in poor response to adjuvant and neoadjuvant chemoradiotherapy. Certain studies of GSRC showed the disputed effectiveness of hyperthermic intraperitoneal chemotherapy and immunotherapy. Our aim was to discuss how an improved understanding of these therapeutic benefits may provide better treatment selection for patients, and therefore improve survival. The challenges in the new understanding of GSRC in routine practice and pathology, and the current limitations of treatment will also be discussed.

Accuracy of endoscopic size measurements of early gastric signet ring cell carcinoma

BACKGROUND AND AIMS

Indications for endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) are expanding, but signet ring cell carcinoma (SRC) is still unclear because of its unclear boundaries. The purpose of this study was to compare pathologic size and endoscopic size in SRC-type EGC and to find risk factors associated with tumor size underestimation.

METHODS

Medical records of 137 patients diagnosed with SRC-type EGC between January 2009 and December 2016 at our tertiary hospital were reviewed. According to pathologic and endoscopic tumor sizes, they were classified into correct estimation, underestimation, and overestimation groups, and risk factors related to underestimation were analyzed.

RESULTS

Among 137 patients with SRC-type EGC, 77 patients (56.2%) had undergone correct estimation, 43 patients (31.4%) had undergone underestimation, and 17 patients (12.4%) had undergone overestimation. Mean pathologic size (SD) was 20.1 (13.8) mm and mean endoscopic size (SD) was 17.9 (10.1) mm, the correlation coefficients were 0.919 (p < 0.001) , and there was no significant difference between the two groups. Multivariate analysis showed that tumor size more than 20 mm (OR 3.419; 95% CI 1.271-9.194; p = 0.015) and atrophy (OR 6.011; 95% CI 2.311-15.633; p = 0.001) were risk factors for tumor size underestimation.

CONCLUSION

There was no significant difference in pathologic and endoscopic size in SRC-type EGC. Therefore, ESD may be considered as a therapeutic option if the size of the tumor is less than 20 mm and atrophy is not present in the surrounding mucosa.

Subepithelial Spread of Early Gastric Signet Ring Cell Carcinoma: How Far They Can Reach?

INTRODUCTION

Although signet ring cell carcinoma (SRC) is a poorly differentiated cancer subtype, recent studies suggest that endoscopic resection can be applied in small, mucosal early gastric SRC. However, other studies report frequent positive lines at the lateral resection margin after endoscopic treatment. Subepithelial spread beneath normal mucosa can exist in SRC, and such lesions may be the cause of positive margins after endoscopic resection. Thus, we conducted a retrospective study in order to evaluate the significance of subepithelial spread in early gastric SRC.

METHOD

Medical records of early gastric SRC patients who underwent surgery or endoscopic resection from January 2011 to December 2016 at a single tertiary hospital (Daejeon, South Korea) were reviewed to examine subepithelial spread and clinical datum. Two expert pathologists reviewed all pathologic specimens, and only patients showing a pure SRC component were included.

RESULTS

Eighty-six patients were initially enrolled, and subepithelial spread existed in 62 patients (72.1%). The mean distance of subepithelial spread was 1,132.1 µm, and the maximal distance was 6,000 μm. Only discoloration was significantly associated with the presence of a subepithelial spread (p < 0.05, χ2 test, and logistic regression test). Distance of subepithelial spread did not correlate with total lesion size.

CONCLUSION

Subepithelial spread of early gastric SRC occurs frequently and can reach up to 6 mm. Lesion discoloration may be associated with the presence of subepithelial spread. Our results suggest that careful decision of the margin is needed when performing endoscopic resection of early gastric SRC.

State of the art for gastric signet ring cell carcinoma: from classification, prognosis, and genomic characteristics to specified treatments

Gastric cancer (GC) is responsible for 9% of cancer deaths worldwide. Over 950,000 new cases are diagnosed each year, and about 90% of them are in advanced stage, requiring chemotherapy. In Europe there has been research based on pre- and postoperative chemotherapy treatment, using 5-fluorouracil, epirubicin, cisplatin, capecitabine, and docetaxel. Chemotherapy significantly impairs the quality of life of patients; however, the final effects are not always satisfactory. There is scientific evidence that gastric mucus tumors and signet ring cell carcinomas have a pattern of specific signatures, that distinguish them from other gastric cancer subtypes, and may be associated with a poor response to systematic treatment. Signet ring cell carcinoma is less chemosensitive than others, and the increase in the percentage of signet ring cells correlates with resistance to chemotherapy. Perioperative chemotherapy in advanced signet ring cell carcinomas is an independent factor of poor prognosis and survival, which is explained by the toxicity of neoadjuvant treatment. Therefore, curative surgical resection enhanced by standardized lymphadenectomy remains the recommended gold standard in GC therapy. According to presented studies, early detection and aggressive treatments for this subtype of GC is a reasonable approach. This review paper is mostly addressed to physicians who are interested in updating to the state of the art concerning different subtypes of gastric carcinoma.

Comparing outcomes for endoscopic submucosal dissection between Eastern and Western countries: A systematic review and meta-analysis

AIM

To compare endoscopic submucosal dissection (ESD) outcomes between Eastern and Western countries.

METHODS

A systematic review and meta-analysis was performed using PubMed, MEDLINE, Web of Science, CINAHL and EBM reviews to identify studies published between 1990 and February 2016. The primary outcome was the efficacy of ESD based on information about either curative resection, en bloc or R0 resection rates. Secondary outcomes were complication rates, local recurrence rates and procedure times.

RESULTS

Overall, 238 publications including 84318 patients and 89512 gastrointestinal lesions resected using ESD were identified. 90% of the identified studies reporting ESD on 87296 lesions were conducted in Eastern countries and 10% of the identified studies reporting ESD outcomes in 2216 lesions were from Western countries. Meta-analyses showed higher pooled percentage of curative, en bloc, and R0 resection in the Eastern studies; 82% (CI: 81%-84%), 95% (CI: 94%-96%) and 89% (CI: 88%-91%) compared to Western studies; 71% (CI: 61%-81%), 85% (CI: 81%-89%) and 74% (CI: 67%-81%) respectively. The percentage of perforation requiring surgery was significantly greater in the Western countries (0.53%; CI: 0.10-1.16) compared to Eastern countries (0.01%; CI: 0%-0.05%). ESD procedure times were longer in Western countries (110 min vs 77 min).

CONCLUSION

Eastern countries show better ESD outcomes compared to Western countries. Availability of local ESD expertise and regional outcomes should be considered for decision making to treat gastrointestinal lesions with ESD.

Tailored treatment for signet ring cell gastric cancer

Gastric cancer with Laurèn diffuse types is increasing in the West. The raising trend is more evident when considering signet ring cells (SRC) histology. However, to control the biologic potential of this GC subtype, some hypotheses of tailored therapeutic strategies for SRC cancers have been made. A review of the literature was performed using the key words "signet ring cells" AND "gastric cancer". Results of literature review were descriptively reported. Endoscopic submucosal dissection (ESD), according to the Japanese extended criteria, could be a therapeutic option for early SRC tumours. However, according to the evidences from more recent studies, indications for ESD to these tumours types should be carefully considered. Concerning the optimal surgical treatment, considering the high lymphotropism and infiltrating behaviour of SRC histotype, the extension of gastric resection should be wider than for intestinal type cancer and laparoscopic surgery should be performed carefully. Moreover, D3 lymphadenectomy could provide a benefit in diffuse-type and SRC histology. The role of surgery in gastric cancer with peritoneal carcinomatosis is still debated and studies on this topic should stratify the good results according to GC histotype. Finally, despite the evidences of chemoresistance in SRC, ongoing randomized trials suggest that multimodal therapy could be the best treatment. Based on the assumption that SRC tumours have specific features, they deserve a specific multimodal treatment. However, a preliminary step to generate strong evidences in this field is the standardization of terminology used to define signet ring cells carcinoma.

Incidence, Survival, and Predictors of Lymph Node Involvement in Early-Stage Gastric Signet Ring Cell Carcinoma in the US

INTRODUCTION

The incidence, survival, and propensity for nodal metastasis in early-stage gastric signet ring cell carcinoma have not been defined in the United States. These data are critical determinants for treatment allocation.

METHODS

Cases of gastric signet ring cell carcinoma were extracted from the national SEER database for the years 2004-2013. Age-standardized incidence was derived. Survival was calculated using the Kaplan-Meier method. Univariate and multivariate analyses were performed to identify predictors of nodal metastasis. Exclusion criteria included neoadjuvant radiotherapy and lack of histologic or nodal data.

RESULTS

A total of 10,624 cases were initially identified. The analysis cohort included 506 cases with early T-stage N0M0 disease following exclusions. The incidence was 0.094 per 100,000 person-years. The 5-year survival rate was 82.8%. Tumor stage (p < 0.001) and size (p < 0.001) were independent predictors of nodal metastasis. The incidence of nodal involvement for T1a tumors <2 cm was 5.4% (p < 0.004).

CONCLUSION

The incidence of potentially resectable signet ring gastric carcinoma has not changed significantly over the past decade. While presenting with predominantly high-grade histology, early T-stage disease has a high survival rate. Small T1a tumors have low rates of nodal metastasis, suggesting that an endoscopic resection could be considered in this subset.

Signet ring cell carcinoma of early gastric cancer, is endoscopic treatment really risky?

Signet ring cell carcinoma (SRC) is a poorly differentiated cancer of the stomach. Generally, poorly differentiated cancer is believed to show poor prognosis and aggressive behavior. Recently, however, there is debate on the aggressiveness of SRC in early gastric cancer (EGC). We therefore studied postoperation biopsies to investigate the aggressiveness of SRC in EGC.We reviewed medical records of patients with EGC who had surgery from January 2011 to December 2015 in a tertiary hospital in Daejeon, South Korea. We evaluated the histologic type, invasion depth, lymphovascular invasion (LVI), and lymph node (LN) metastasis.A total of 822 EGC lesions from 789 patients were studied. Approximately 498 differentiated cancer, 65 poorly differentiated cancer, 91 SRC, 26 poorly differentiated with SRC, 41 mixed type, 10 medullary carcinoma, and 91 poorly cohesive carcinoma other than SRC were included. LN metastasis was associated with the histologic type of EGC (P = .000). Nine percent of differentiated cancer, 21.5% of poorly differentiated cancer, 5.5% of SRC, 11.5% of poor differentiation with SRC, 26.8% of mixed type, 20% of medullary type, and 15.4% of poorly cohesive carcinoma other than SRC showed LN metastasis. The risk of SRC was not higher than well to moderated differentiated cancer (odds ratio [OR] = 0.842, P = .768). Risk of LVI was also similar with LN metastasis. Compared with differentiated cancer, OR of SRC was 1.969 (P = .172).Our results show that SRC is not more aggressive than differentiated cancer. SRC may be considered a candidate for endoscopic treatment.

Endoscopic submucosal dissection of gastric tumors: A systematic review and meta-analysis

AIM: To systematically review the medical literature in order to evaluate the safety and efficacy of gastric endoscopic submucosal dissection (ESD).

METHODS: We performed a comprehensive literature search of MEDLINE, Ovid, CINAHL, and Cochrane for studies reporting on the clinical efficacy and safety profile of gastric ESD.

RESULTS: Twenty-nine thousand five hundred and six tumors in 27155 patients (31% female) who underwent gastric ESD between 1999 and 2014 were included in this study. R0 resection rate was 90% (95%CI: 87%-92%) with significant between-study heterogeneity (P < 0.001) which was partly explained by difference in region (P = 0.02) and sample size (P = 0.04). Endoscopic en bloc and curative resection rates were 94% (95%CI: 93%-96%) and 86% (95%CI: 83%-89%) respectively. The rate of immediate and delayed perforation rates were 2.7% (95%CI: 2.1%-3.3%) and 0.39% (95%CI: 0.06%-2.4%) respectively while rates of immediate and delayed major bleeding were 2.9% (95%CI: 1.3-6.6) and 3.6% (95%CI: 3.1%-4.3%). After an average follow-up of about 30 mo post-operative, the rate of tumor recurrence was 0.02% (95%CI: 0.001-1.4) among those with R0 resection and 7.7% (95%CI: 3.6%-16%) among those without R0 resection. Overall, irrespective of the resection status, recurrence rate was 0.75% (95%CI: 0.42%-1.3%).

CONCLUSION: Our meta-analysis, the largest and most comprehensive assessment of gastric ESD till date, showed that gastric ESD is safe and effective for gastric tumors and warrants consideration as first line therapy when an expert operator is available.

Early gastric cancer with mixed histology predominantly of differentiated type is a distinct subtype with different therapeutic outcomes of endoscopic resection

BACKGROUND

Safety of endoscopic resection (ER) for early gastric cancers (EGC) with mixed histology predominantly of differentiated type has not been securely established, since those lesions tend to exhibit lymph node metastasis, compared to pure differentiated type. The purpose of this study was to evaluate clinicopathologic characteristics, therapeutic outcomes, and risk for lymph node metastasis in predominantly differentiated mixed EGC treated by ER.

METHODS

A total of 1,016 patients with 1,039 EGCs underwent ER between January 2007 and June 2013. Enrolled lesions were divided into groups of either pure differentiated (n = 1,011) or predominantly differentiated mixed (n = 28), according to the presence of mixed histology predominantly of differentiated type in ER specimen.

RESULTS

Mixed histology predominantly of differentiated type was diagnosed in 2.7% of lesions. Larger size, mid-third location, and moderately differentiated histology on forceps biopsy were independent risk factors for the predominantly differentiated mixed histologic type of EGC in multivariate analysis. En bloc resection rate tended to be lower, and complete and curative resection rates were significantly lower in the predominantly differentiated mixed group. The rate of lymph node metastasis in the lesions with additional operation tended to be higher, in this mixed histology group.

CONCLUSIONS

Larger size, mid-third location, and moderately differentiated histology on forceps biopsy carry the significant risk for mixed histology predominantly of differentiated type. EGC with predominantly differentiated mixed histologic type affects therapeutic outcomes and consequent clinical course accompanied by possibly higher risk for lymph node metastasis. The safety of ER for predominantly differentiated mixed EGC should be validated by further prospective investigation.