Prognostic Impact of the Signet Ring Cell Type in Node-Negative Gastric Cancer

Clinical Features of Gastric Signet Ring Cell Cancer: Results from a Systematic Review and Meta-Analysis

BACKGROUND

Conflicting results about the prognostic relevance of signet ring cell histology in gastric cancer have been reported. We aimed to perform a meta-analysis focusing on the clinicopathological features and prognosis of this subgroup of cancer compared with other histologies.

METHODS

A systematic literature search in the PubMed database was conducted, including all publications up to 1 October 2021. A meta-analysis comparing the results of the studies was performed.

RESULTS

A total of 2062 studies referring to gastric cancer with signet ring cell histology were identified, of which 262 studies reported on its relationship with clinical information. Of these, 74 were suitable to be included in the meta-analysis. A slightly lower risk of developing nodal metastases in signet ring cell tumours compared to other histotypes was found (especially to undifferentiated/poorly differentiated/mucinous and mixed histotypes); the lower risk was more evident in early and slightly increased in advanced gastric cancer. Survival tended to be better in early stage signet ring cell cancer compared to other histotypes; no differences were shown in advanced stages, and survival was poorer in metastatic patients. In the subgroup analysis, survival in signet ring cell cancer was slightly worse compared to non-signet ring cell cancer and differentiated/well-to-moderately differentiated adenocarcinoma.

CONCLUSIONS

Most of the conflicting results in signet ring cell gastric cancer literature could be derived from the lack of standardisation in their classification and the comparison with the different subtypes of gastric cancer. There is a critical need to strive for a standardised classification system for gastric cancer, fostering clarity and coherence in the forthcoming research and clinical applications.

Molecular profiling of signet-ring-cell carcinoma (SRCC) from the stomach and colon reveals potential new therapeutic targets

Signet ring cell carcinoma (SRCC) is rare: about 10% of gastric cancer (GC) and 1% of colorectal cancer (CRC). SRCC is associated with poor prognosis, however the underlying molecular characteristics are unknown. SRCCs were analyzed using NGS, immunohistochemistry, and in situ hybridization. Tumor mutational burden (TMB) was calculated based on somatic nonsynonymous missense mutations, and microsatellite instability (MSI) was evaluated by NGS of known MSI loci. A total of 8500 CRC and 1100 GC were screened. Seventy-six SRCC were identified from the CRC cohort (<1%) and 98 from the GC cohort (9%). The most frequently mutated genes in CRC-SRCC were TP53 (47%), ARID1A (26%), APC (25%); in GC-SRCC were TP53 (42%), ARID1A (27%), CDH1 (11%). When compared to non-SRCC histology (N = 3522), CRC-SRCC (N = 37) more frequently had mutations in BRCA1 (11% vs 1%, P < 0.001) and less frequently mutations in APC (19% vs 78%, P < 0.001), KRAS (22% vs 51%, P = 0.001) and TP53 (47% vs 73%, P = 0.001). Among the GC cohort, SRCC (N = 54) had a higher frequency of mutations in CDH1, BAP1, and ERBB2, compared to non-SRCC (N = 540). Our data suggest that SRCCs harbor a similar molecular profile, regardless of the tumor location. Tailored therapy may become available for these patients.

Prognosis and Biological Behavior of Gastric Signet-Ring Cell Carcinoma Better or Worse: A Meta-Analysis

BACKGROUND

The clinical pathology of gastric signet-ring cell carcinoma (SRC) is still unclear. This meta-analysis was performed to evaluate the difference in biological behavior and prognosis between SRC and non-signet ring cell carcinoma (NSRC).

METHODS

A total of 58 eligible studies were analyzed using RevMan and other auxiliary software. Biological behaviors were compared based on odds ratio (OR) and mean difference (MD). Hazards ratio (HR) was calculated for prognosis based on Kaplan-Meier curves.

RESULTS

Totally, 28,946 SRC patients were compared with 81,917 NSRC patients. Compared with NSRC patients, lower male: female ratio (OR = 0.53, P < 0.01), younger age (MD = -4.89, P < 0.01), more middle location (OR = 1.64, P < 0.01), more depressed type at early stage (OR = 1.31, P < 0.05), higher incidence of Borrmann type IV (OR = 1.96, P < 0.01), less lymph node metastasis at early stage (OR = 0.78, P < 0.05), better prognosis at early stage (HR = 0.59, P < 0.01), and worse prognosis at advanced stage (HR = 1.19, P < 0.01) were associated with SRC patients.

CONCLUSION

The prognosis of SRC at early stage is better than other types of gastric cancer, while that of SRC at advanced stage is relatively poorer.

Difference Between Signet Ring Cell Gastric Cancers and Non-Signet Ring Cell Gastric Cancers: A Systematic Review and Meta-Analysis

Background: There is controversy about the characteristics and prognostic implications of signet ring cell gastric cancers and non-signet ring cell gastric cancers.

Objective: This study aims to evaluate clinicopathological characteristics and prognoses of signet ring cell carcinoma (SRCC) and non-signet ring cell carcinoma (NSRCC) of stomach.

Methods: Studies compared between SRCC and NSRCC of the stomach after gastrectomy and published before September 1st, 2020, in the PubMed, Cochrane, and Embase databases, were identified systematically.

Results: A total of 2,865 studies were screened, and 36 studies were included, with 19,174 patients in the SRCC group and 55,942 patients in the NSRCC group. SRCC patients were younger in age (P < 0.001), less likely to be male patients (P < 0.001), more afflicted with upper third lesions (P < 0.001), and presenting with more Borrmann type IV tumors (P = 0.005) than NSRCC patients. Lymph nodes metastasis was similar between SRCC and NSRCC patients with advanced tumor stage (OR: 0.86, 95% CI: 0.671.10, P = 0.23), but lower in the SRCC than NSRCC patients with early tumor stage (OR: 0.73; 95% CI: 0.560.98, P = 0.02). SRCC patients had comparable survival outcomes with NSRCC patients for early gastric cancers (HR: 1.05, 95% CI: 0.651.68, P < 0.001) but had significantly poor prognosis for patients with advanced tumor stage (HR: 1.50, 95% CI: 1.281.76, P < 0.001).

Conclusions: Signet ring cell carcinomas of the stomach are an increasingly common histopathological subtype of gastric cancers. These kinds of patients tend to be younger in age and more often female. Although, signet ring cell gastric cancer is a negative prognostic factor for patients with advanced stage. The difference is that for early stage of signet ring cell gastric cancers, it has low lymph nodes metastasis rate and comparable prognosis with non-signet ring cell cancers.

Signet Ring Cell Features are Associated with Poor Response to Neoadjuvant Treatment and Dismal Survival in Patients with High-Grade Esophageal Adenocarcinoma

BACKGROUND

While the prognosis of patients with locoregional esophageal adenocarcinoma (EAC) has improved in the neoadjuvant treatment (NAT) era, high-grade histology (G3) is still associated with a limited treatment response. We sought to investigate oncologic outcomes in patients after esophagectomy for G3 EAC and to identify predictors of poor survival among these patients.

METHODS

Patients with EAC who underwent resection with curative intent in 2011-2018 were divided by histologic grade (G3, G1/2) and compared for overall survival (OS). Cox regression was performed to analyze the response to NAT and the predictive role of signet ring cell (SRC) features.

RESULTS

The cohort included 163 patients, 94 (57.7%) with G3 histology. NAT was administered to 69 (73.4%) patients. Following resection, OS in the G3 EAC group was 30 months (95% confidence interval [CI] 23.9-36.1). On univariate analysis, G3 disease (p = 0.050) and SRC features (p = 0.019) predicted low OS. Median survival in the G3 EAC group was worse in patients with SRC histology (18 months, 95% CI 8.6-27.4) than those without (30 months, 95% CI 23.8-36.1; p = 0.041). No patients with SRC histology were alive at 5 years of follow-up. Among all patients administered NAT, 88.2% of those with SRC showed minimal or no pathologic response and only 27.8% were downstaged.

CONCLUSIONS

High-grade histology was found in most patients with EAC and predicted poor survival and treatment response. SRC features in patients with G3 disease were associated with lower OS. The benefit of NAT for G3 EAC in patients with SRC histology appears limited.

Different prognostic significance of signet ring cell histology for early and advanced gastric cancer patients: a systematic review and meta-analysis

OBJECTIVE

To review relevant studies and perform a meta-analysis to evaluate the prognostic significance of signet ring cell (SRC) histology for gastric cancer (GC) patients.

METHODS

Systematic literature search was performed using PubMed and Embase databases. The relevant data were extracted and the association between SRC histology and survival outcome were evaluated using a fixed-effect or random-effect model.

RESULTS

A total of 21 studies were included in this meta-analysis. The prevalence of SRC histology varied from 8.7% to 50%. SRC histology type was associated with poorer OS (HR: 1.12, 95%CI: 1.01-1.23, P = 0.034; I² = 85.1%) and DFS (HR: 1.17, 95%CI: 1.00-1.37, P = 0.040; I² = 63.6%). The subgroup analysis indicated that SRC type had a better OS than non-SRC type for early GC patients (HR: 0.60, 95%CI: 0.48-0.75, P < 0.001; I² = 33.7%). However, it was a poor prognostic factor for advanced GC when excluding stage IV patients (HR: 1.18, 95%CI: 1.07-1.29, P < 0.001; I² = 6.5%). SRC type had a higher risk of peritoneal recurrence than non-SRC type (OR: 1.36, 95%CI: 1.06-1.75, P = 0.017; I² = 1.3%).

CONCLUSION

SRC type had a distinctly different prognostic significance for early and advanced GC patients. SRC type was associated with better survival outcomes in early GC patients, but it was a predictive factor for poor survival in advanced GC patients.

Lymph Node Yield Following Packet Submission After Isolation By Surgeon During Gastrectomy

Purpose

To compare the lymph node yields of lymph node packet submission (PS), packet submission after isolation by surgeons (PSI), and en bloc lymph node submission (EBS) after gastrectomy.

Methods

We conducted a prospective study including 118 gastric cancer patients who underwent gastrectomy between June 2016 and August 2016. We also retrospectively reviewed 607 patients who underwent gastrectomy from May 2015 to May 2016. Following gastrectomy, lymph node specimens were either submitted en bloc (EBS group), divided into packets with accompanying adipose tissue according to the lymph node stations (PS group), or isolated individually based on the surgeon’s visualization and palpation before submission to the Pathology Department (PSI group).

Results

The average lymph node yield was significantly higher in the PSI compared with the PS group in the prospective study (46.5±19.4 vs 31.8±11.1), and significantly higher in the PS compared with the EBS group in the retrospective study (31.5±12.6 vs 23.9±8.9) (both P<0.001). There was no significant difference in positive lymph node yields in either of these comparisons (prospective study, P=0.581; retrospective study, P=0.489). The survival curve indicated no significant difference between the PS and PSI groups (log rank P=0.957); however, these three groups share different lymph node ratio (LNR).

Conclusion

PSI could yield more lymph nodes than PS or EBS with a lower LNR at pathological examination. However, the difference in lymph nodes harvested had no impact on survival, which may need further investigation.

lncRNA SPRY4-IT1 Regulates Cell Proliferation and Migration by Sponging miR-101-3p and Regulating AMPK Expression in Gastric Cancer

Increasing evidence indicates that long noncoding RNA SPRY4 intronic transcript 1 (lncRNA SPRY4-IT1) has been reported to be associated with the progression of several cancers, but its expression level and the function of SPRY4-IT1 in the progression of gastric cancer (GC) have been rarely reported. Here we found that SPRY4-IT1 was upregulated in GC. In vitro experiments revealed that SPRY4-IT1 knockdown significantly inhibited GC cell proliferation by causing G1 arrest and promoting apoptosis, whereas SPRY4-IT1 overexpression promoted cell growth. Further functional assays indicated that SPRY4-IT1 overexpression significantly promoted cell migration and invasion. Bioinformatics analysis predicted that there is a SPRY4-IT1/miR-101-3p/AMPK axis in GC progression. A dual-luciferase reporter system validated the direct interaction of SPRY4-IT1, miR-101-3p, and AMPK. Western blot verified that the inhibition of SPRY4-IT1 decreased AMPK expression. Furthermore, silencing SPRY4-IT1 suppressed GC growth in vivo. Importantly, we demonstrated that SPRY4-IT1 was upregulated in serum exosomes from GC patients and correlated with cancer metastasis. Altogether, silencing SPRY4-IT1 suppresses the progression of GC by interacting with miR-101-3p and decreasing inhibiting AMPK expression. Taken together, our study demonstrates that SPRY4-IT1 could act as a potential therapeutic target for GC patients.

Prognostic Stratification of Advanced Gastric Signet Ring Cell Carcinoma by Clinicopathological Factors and GALNT14 Genotype

Background: Gastric signet ring cell carcinoma (SRCC) is a histologic variant characterized by abundant intracytoplasmic mucin. Although it has been recognized that gastric adenocarcinoma harboring this feature has poorer prognosis, prognostic stratification within gastric SRCCs themselves has not been clearly defined. N-acetylgalactosaminyltransferase14 (GALNT14) genotype has been associated to poorer treatment outcome in mucinous type colorectal cancer. Here we incorporated clinicopathological factors and GALNT14 genotype to stratify prognosis of advanced gastric SRCC. Methods: Totally 347 gastric SRCC patients were retrospectively enrolled for GALNT14 genotyping. Clinicopathological factors were included for prognosis stratification. Results: Of the 347 patients, 341 underwent radical-intent gastrectomy and 6 received palliative gastrectomy. Kaplan-Meier analysis for overall survival indicated that Tumor-Node-Metastasis staging could only stratify the patients into three prognosis-distinguishable groups: group-1 (stage IA); group-2 (stage IB/IIA) and group-3 (the remaining Tumor-Node-Metastasis stages combined). Multivariate Cox-proportional hazard models for group-3 patients revealed GALNT14 "TT" genotype (P = 0.0482). Tumor size (P = 0.0009), node status (P <0.0001), metastasis status (P = 0.0096), and perineural invasion (P = 0.037) independently associated with unfavorable OS. Exploratory subgroup analysis showed that GALNT14"TT" genotype was associated with unfavorable OS in SRCCs with more aggressive phenotypes: node status >0 (P = 0.0013), lymphatic invasion (P = 0.021), vascular invasion (P = 0.0076) and perineural invasion (P = 0.0161). Accordingly, a scoring system was established capable of stratifying advanced gastric SRCC patients into three distinguishable prognostic subgroups. Conclusions: Gastric SRCC could be stratified into different prognostic subgroups by combining clinicopathological factors and GALNT14 genotype.

Neural Invasion is a Significant Contributor to Peritoneal Recurrence in Signet Ring Cell Gastric Carcinoma

BACKGROUND

Gastric signet ring cell carcinoma (SRC) has shown a favorable outcome in early stages but has a worse prognosis than non-SRC in advanced stages. However, the cause for this stage-dependent prognostic impact has not been determined. This study aimed to compare clinicopathologic features and recurrence patterns between gastric SRC and non-SRC in a cohort of Eastern patients.

METHODS

This study reviewed the prospectively collected data of 764 patients undergoing curative resection for gastric cancer from 2005 to 2008. The demographics, clinicopathologic characteristics, disease-specific survival (DSS) rate, and recurrence-free survival (RFS) rate of the patients were analyzed.

RESULTS

The SRC patients (n = 176) had a worse prognosis than the non-SRC patients (n = 588), especially in stages T3 and T4. Peritoneal recurrence and the incidence of neural invasion (NI) were significantly increased in the SRC patients, albeit only in stages T3 and T4. In the T3 and T4 patients with NI, peritoneal recurrence occurred more frequently in SRC than in non-SRC (28.7% vs. 13.7%; p = 0.001), but not in the T3 and T4 patients without NI. Only in the patients with NI, SRC led to a significantly shorter DSS (67.6 vs. 90.7 months; p = 0.008) and RFS (67.1 vs. 80.3 months; p = 0.036) than non-SRC.

CONCLUSIONS

This report is the first to present the relationship between NI and peritoneal recurrence as the cause of stage-dependent prognoses for SRC. A better understanding of NI may lend insight into cancer spread and recurrence, especially in gastric SRC.

Is the signet ring cell histological type a positive prognostic factor for gastric adenocarcinoma after D2 radical gastrectomy?

BACKGROUND

Previous studies indicated the histological type might have prognostic value in gastric adenocarcinoma patients. The aim of this study was to clarify whether the signet ring cell (SRC) histological type of gastric adenocarcinoma is associated with worse prognosis than pure gastric adenocarcinoma without any mixed histological component (PGA) for patients underwent D2 radical gastrectomy.

METHOD

By the database of 6205 surgical patients with gastric adenocarcinoma at our department between September 2008 and May 2015, we investigated 133 SRC patients and 2847 PGA patients who underwent D2 radical gastrectomy. The clinic and pathologic data, especially tumor and pathology molecular markers, and 5-year overall survival rate were compared between SRC and PGA. The univariate and multivariate analysis were used to testify the prognosis significance of SRC.

RESULTS

SRC was more frequently found in younger (<50), female patients, lower part of stomach and easy to metastasize lymph nodes. And more positive CA19-9 and less positive EGFR were obtained in SRC. The 5-year survival rate was not different between SRC and PGA after D2 radical gastrectomy, even assessed by T stage. Multivariate analysis showed age, T and N stage, CEA, CA19-9 and CA125 were the independent prognostic factors, not included the SRC histological type.

CONCLUSION

Although SRC histological type of gastric adenocarcinoma after D2 radical gastrectomy had its own clinic-pathologic characters, especially in molecular tumor and pathological markers, the histological type of SRC was a negative prognostic factor in gastric adenocarcinoma patients after D2 radical gastrectomy.

Clinicopathological Characteristics and Prognostic Value of Signet Ring Cells in Gastric Carcinoma: A Meta-Analysis

Background and Objectives: Previous studies of the prognostic value of the signet ring cell (SRC) type have yielded inconsistent results. Therefore, the aim of the present meta-analysis is to explore the clinicopathological characteristics and prognostic value of SRCs.

Methods: Relevant articles that compared SRC and non-SRC type in PubMed and Web of Science were comprehensively searched. Then, a meta-analysis was performed.

Results: A total of 19 studies including 35947 cases were analyzed. Compared with non-SRC patients, SRC patients tended to be younger (WMD: -3.88, P=0.001) and predominantly female (OR: 1.60, P<0.001). Additionally, SRC patients exhibited less upper third tumor location (OR: 0.62, P<0.001) and less frequent hematogenous metastasis (OR: 0.41, P<0.001). There was no difference in overall survival (OS) between SRC and non-SRC patients in the total population (HR: 1.02, P=0.830). Early gastric cancer with SRCs was associated with better OS (HR: 0.57, P=0.002), while advanced gastric cancer with non-SRCs was associated with a worse prognosis (HR: 1.17, P<0.001).

Conclusions: This meta-analysis revealed that SRC tends to affect young females and tends to be located in the middle and lower third of the stomach. Early SRCs are associated with better prognoses, while advanced SRCs are associated with worse prognoses.

Signet Rings Around the World

Esophageal and gastric adenocarcinoma of signet ring subtype is aggressive and portends a poor prognosis. This subtype of an already aggressive cancer metastasizes widely and can progress quickly. Hart and colleagues outline an unusual and specific metastasis following resection of signet ring esophageal adenocarcinoma. More frequent surveillance for resected patients may help identify metastases early.