Adenocarcinomas of esophagus and cardia in comparison with gastric carcinoma

miR-1262 suppresses gastric cardia adenocarcinoma via targeting oncogene ULK1

Gastric cardia adenocarcinoma (GCA) is one of two main gastric cancer subtypes and has its own epidemiological, pathogenic and clinical characteristics. Genetic polymorphisms locating in a microRNA (miRNA) gene enhancer could transcriptionally regulates miRNA expression via impacting binding of transcriptional factors. It is still unclear how miR-1262 and a potential regulatory rs12740674 polymorphism mapping to a strong enhancer region of miR-1262 contribute to GCA development. We genotyped miR-1262 rs12740674 in two independent case-control sets consisting of 1,024 GCA patients and 1,118 controls, and found that the rs12740674 CT or TT genotype carriers had a 0.69-fold decreased risk to develop GCA compared to the CC genotype carriers (95% confidence interval=0.57-0.84, P=2.1×10^-4). In the genotype-phenotype correlation analyses of 21 pairs of GCA-normal tissues, the rs12740674 CT or TT genotype was associated with significantly increased levels of miR-1262. Cell proliferation, wound healing and transwell assays elucidated that miR-1262 is a novel GCA tumor suppressor. Consistently, a significantly down-regulated level of miR-1262 exists in GCA specimens compared to normal tissues. Furthermore, multiple lines of evidences indicated that oncogene ULK1 is the target gene of miR-1262 in GCA. Our findings demonstrate miR-1262 transcriptionally modulated by an enhancer genetic variant suppresses GCA via targeting oncogene ULK1. Our data highlight miR-1262 as a promising diagnostic marker and therapeutic target for GCA.

Genetic variations associated with telomere length confer risk of gastric cardia adenocarcinoma

BACKGROUND

Aberrant telomere lengthening is a critical feature of malignant cells. Short leukocyte telomere length (LTL) confers elevated risk of gastric cardia adenocarcinoma (GCA). Multiple genome-wide association studies (GWAS) identified various single-nucleotide polymorphisms (SNPs) associated with LTL in different ethnic populations. However, it remains largely unexplored how these genetic variants are involved in GCA susceptibility.

METHODS

We systematically screened GWAS-identified candidate SNPs and tested the impact of 30 polymorphisms in genes associated with interindividual LTL variation on GCA using two-stage case-control comparisons consisting of 1024 GCA patients and 1118 controls.

RESULTS

We observed that CXCR4 rs6430612, TERT rs10069690, and rs2853676 as well as VPS34 rs2162440 are significantly associated with GCA development. A 0.64-fold decreased risk of GCA is associated with the CXCR4 rs6430612 CT genotype compared with the CC genotype (P = 0.002). On the contrary, the TERT rs10069690 TT genotype carriers had a 1.83-fold increased risk to develop GCA compared to the CC genotype carriers (P = 5.8×10^-6). We also detected a 2.17-fold increased OR for GCA that was associated with the TERT rs2853676 TT genotype (P = 2.6×10^-6). In addition, the odds of having the VPS34 rs2162440 GA genotype in GCA patients were 1.35 compared with the GG genotype (P = 0.002). In stratified analyses, the association between TERT rs10069690 polymorphism and GCA was more pronounced in nonsmokers (P_interaction = 9.7 × 10^-5) and nondrinkers (P_interaction = 4.6 × 10^-5).

CONCLUSIONS

Our results highlight the importance of both LTL and LTL-related genetic variants to GCA predisposition.

Leukocyte telomere length and risk of gastric cardia adenocarcinoma

As a chromosome stabilizer, telomeres play an essential part in maintaining the stability and integrity of human genome. Shortened telomeres have been associated with the development of cancers but it is still largely unclear whether leukocyte telomere length contributes to predisposition of gastric cardia adenocarcinoma (GCA). We conducted a case-control study consisting of 524 GCA cases and 510 controls to assess the association between telomere length in peripheral blood leukocytes and GCA risk in a Chinese Han population. The GCA patients had significantly overall shorter relative leukocyte telomere length (RTL) (median ± SD: 1.10 ± 0.54) when compared with the controls (1.24 ± 0.58). Individuals with the shortest quartile of RTL performed a doubled GCA risk (OR = 2.18; 95% CI = 1.47–3.22, P = 9.90 × 10⁻⁵) when compared with those with the highest quartile. We also found that telomere shortening and smoking have a significantly synergistic effect in intensifying risk of GCA (OR = 7.03, 95% CI = 4.55–10.86, P = 1.43 × 10⁻¹⁸). These findings indicate that short RTL contributes to increased susceptibility of gastric cardia adenocarcinoma and might be a promising marker to identify high-risk individuals combined with lifestyle risk factors.

HER2 positivity in gastric and esophageal adenocarcinoma: clinicopathological analysis and comparison

PURPOSE

Primary tumor classification of gastric or esophageal cancer has changed significantly with recent alterations of the tumor-node-metastasis (TNM) staging system. Considering these alterations, human epidermal growth factor receptor 2 (HER2) positivity rates were determined and compared in gastric and esophageal adenocarcinoma. Additionally, HER2 positivity in relation to other clinicopathological characteristics was evaluated.

METHODS

A total of 321 patients with histologically confirmed invasive gastric or esophageal adenocarcinoma were examined for HER2 by immunohistochemy (IHC) and chromogenic in situ hybridization (CISH). IHC 3+ or IHC 2+/CISH-positive tumors were considered HER2 positive. Clinicopathological characteristics were retrospectively retrieved from the patient records.

RESULTS

HER2 positivity was found in 50 of 321 patients (15.6 %). In univariate and multivariate logistic models, HER2 positivity rates were significantly higher in esophageal primary tumors (esophageal 25.0 % vs. gastric 7.4 %) and in intestinal histological tumor type (intestinal 22.6 % vs. diffuse/mixed 5.7 %). No significant differences in HER2 positivity were found between males and females, age below and above 65 years, biopsies and surgical specimens or advanced and early-stage disease. Using the 7th TNM edition, many tumors (30.5 % of all included tumors and 64.5 % of all esophageal primary tumors) previously classified as gastric cancer are now classified as esophageal cancer.

CONCLUSIONS

HER2 positivity occurs in 15.6 % of invasive gastroesophageal adenocarcinoma in Western patients, of which the majority is esophageal primary tumors and of the intestinal tumor type. With the introduction of the 7th TNM edition, a large number of tumors previously classified as gastric are now classified as esophageal tumors instead, with relatively high HER2 positivity rates in these esophageal primary tumors.

Pathologic diagnostics of HER2 positivity in gastroesophageal adenocarcinoma

OBJECTIVES

The human epidermal growth factor receptor 2 (HER2) oncogene shows overexpression in 15% to 30% of gastroesophageal adenocarcinomas. Targeted anti-HER2 therapy with trastuzumab has been recently validated in advanced gastric and gastroesophageal junction cancer treatment. A standardized modified scoring system was recently introduced for gastroesophageal HER2 scoring. We aimed to validate this scoring system, including an analysis of interobserver variability of immunohistochemistry (IHC) scoring.

METHODS

In total, 323 patients with histologically confirmed invasive gastric or esophageal adenocarcinoma were examined for HER2 by IHC and chromogenic in situ hybridization (CISH). IHC 3 + or IHC 2 +/CISH positive tumors were considered HER2 positive. Interobserver variability on IHC scoring using the currently standard modified HER2 scoring system was determined among three clinical pathologists. Clinicopathologic characteristics were retrospectively retrieved from the patient records.

RESULTS

HER2 positivity was found in 50 (15.5%) of 323 patients. Interobserver agreement on IHC scoring was high (κ = 0.78). Most disagreement was found in diffuse or mixed tumor types and in weak to moderate stained samples (IHC 2 +). The HER2 IHC scoring system is sensitive in differentiating HER2 status before ISH.

CONCLUSIONS

The currently used standardized HER2 scoring system is an excellent, clinically applicable method to establish HER2 status in appropriately educated and trained pathologists.

Interleukin-4 and -8 gene polymorphisms and risk of gastric cancer in a population in Southwestern China

BACKGROUND

Gastric carcinogenesis is a complicated process that involves environmental and genetic factors like interleukin-4 (IL-4) and IL-8. Single nucleotide polymorphisms in their genes are associated with changed levels of gene expression. Here, we investigated the association between IL4-590 C>T and IL8-251T>A and gastric cancer (GC) risk in Sichuan of Southwestern China.

MATERIALS AND METHODS

We surveyed the research subjects using a self-designed questionnaire with questions on demographic factors and putative risk factors. Approximately 2-5ml of whole blood was collected after field survey to analyze IL4-590 C>T and IL8-251T>A genotypes using MALDI-TOF MS.

RESULTS

Our study recruited 308 pairs of GC patients and controls, including 224 (72.7%) men and 84 (27.3%) women in each group. There were 99 cardia and 176 noncardia GC patients in the case group. The case and control groups had an average age of 57.7±10.6 (mean±SD) and 57.6±11.1 years. GC patients reported a significantly greater proportion of family history of cancer (29.9% vs 10.7%, p<0.01) and drinking (54.6% vs 43.2%, p<0.01) than did controls. Variant genotypes of IL-4-590 C>T and IL-8-251 T>A were not associated with overall GC risk (adjusted OR, 0.89; 95%CI, 0.61-1.28 for CT or CC vs TT; adjusted OR, 1.14; 95%CI, 0.86-1.79 for TA or AA vs TT). Stratification analysis of two SNPs for risk by subsites only found that variant IL-8-251 TA or AA genotype was associated with increased noncardia GC risk (adjusted OR, 2.58; 95%CI, 1.19-5.57). We did not observe interactions between the IL-8-251 T>A genotype and smoking (adjusted OR, 0.38; 95%CI, 0.08-1.79) or drinking (adjusted OR, 0.36; 95%CI, 0.08-1.65) for risk of noncardia GC.

CONCLUSIONS

Our data indicate no association between the two SNPs of IL-4-590 and IL-8-251 with overall GC risk, while the IL-8-251 TA or AA genotype conferred risk of cardia GC. Our findings contribute to the evidence body for risk of SNPs associated with the development of gastric cancer in this region.

HER-2/neu gene amplification in relation to expression of HER2 and HER3 proteins in patients with esophageal adenocarcinoma

BACKGROUND

Human epidermal growth factor receptor 2 (HER2) is a therapeutic target in patients with esophageal adenocarcinoma (EAC), with gene amplification used as a selection criterion for treatment, although to the authors' knowledge the concordance between amplification and HER2 protein expression remains undefined in EAC. Furthermore, the association between HER2 and its interacting partner, human epidermal growth factor receptor 3 (HER3), is unknown yet appears to be of potential therapeutic relevance.

METHODS

Patients with untreated EACs (N = 673) were analyzed for HER2 amplification and polysomy 17 by fluorescence in situ hybridization in parallel with immunohistochemistry (IHC) (IHC scores of 0-1+, 2+, and 3+). Amplification was defined as HER2/CEP17 ≥ 2. HER3 expression by IHC was analyzed in randomly selected cases (n = 224). IHC and fluorescence in situ hybridization results were compared using least squares linear regression.

RESULTS

Overall, 17% of the EACs (116 of 673 EACs) were HER2-amplified with an amplification frequency that was highest among IHC3+ cases (89%) and declined among IHC2+ cases (13%) and IHC0 to IHC1+ cases (4%). Among HER2-amplified cases, the level of amplification increased linearly with HER2 membranous expression (HER2/CEP17 ratio: 7.9 in IHC3+ and 5.5 in IHC2+ vs 2.8 in IHC0 to IHC1+ [P < .0001]), with 14% of amplified tumors demonstrating absent/faint expression (IHC0 to IHC1+). Polysomy 17 was not found to be associated with HER2 expression. Cytoplasmic HER3 expression was detected in 87% of tumors (195 of 224 tumors) and was found to be significantly associated with better differentiation (P < .0001). Stepwise increases in HER3 expression were associated with higher HER2 expression levels (P = .0019).

CONCLUSIONS

Levels of HER2 protein expression and amplification were found to be linearly associated and highly concordant. Among amplified tumors with absent/faint expression, the level of amplification was low. Frequent expression of HER3 suggests its relevance as a therapeutic target, and its significant association with HER2 supports ongoing efforts to inhibit HER2/HER3 in patients with EAC.

Positive association between Toll-like receptor 4 gene +896A/G polymorphism and susceptibility to gastric carcinogenesis: a meta-analysis

Several studies have investigated the association between the Toll-like receptor 4 (TLR4) gene +896A/G polymorphism and gastric carcinogenesis, including gastric cancer and precancerous gastric lesions. However, published results are inconsistent. So, we performed a meta-analysis to assess whether the TLR4 +896A/G single-nucleotide polymorphism (SNP) is a risk factor in gastric cancer development. We searched PubMed and Embase databases for studies that reported the odds ratio (OR) and 95 % confidence interval (CI) for the association between the TLR4 +896A/G SNP and the risk of gastric cancer and/or precancerous lesions with the last update of November 2012. Data were analyzed using Review Manager (Version 5.1), and publication bias was estimated. We included 10 study populations, comprising 2,233 cases and 2,849 controls from 8 publications. The pooled OR was 2.00 (95 % CI = 1.59-2.53) for the G allelic model. Analysis stratified by different stages and anatomic sites of neoplasia resulted in a significantly increased risk associated with gastric cancer (OR = 1.87, 95 % CI = 1.44-2.44), especially the non-cardia subtype (OR = 2.03, 95 % CI = 1.51-2.72). Besides, the G allele emerged as a strong risk factor for precancerous gastric lesions (OR = 2.47, 95 % CI = 1.57-3.88). A subsequent subgroup analysis by Helicobacter pylori-positive ratio in cases (>80 %) indicated an enhancement in the association with precancerous lesions (OR = 3.43, 95 % CI = 1.92-6.13). The TLR4 +896A/G SNP is a risk factor in gastric carcinogenesis, especially in H. pylori-infected patients with precancerous lesions.

A functional polymorphism in MIR196A2 is associated with risk and prognosis of gastric cancer

Genetic variations in miRNAs have been demonstrated to be capable of altering miRNA expression, consequently affecting many cancer-related biological processes. The MIR196A2 rs11614913 (T > C) polymorphism has been reported to be associated with various cancers development and progression. In our study, we aim to explore whether this polymorphism is relevant to the genetic susceptibility and prognosis of gastric cancer in a Chinese population. We analyzed the correlations of rs11614913 polymorphism with gastric cancer susceptibility in test and validation sets. The test set comprised 749 cases and 900 controls, while the validation set enrolled 940 cases and 1046 controls. Moreover, we evaluated the association between the polymorphism and gastric cancer prognosis in the validation set with follow-up information. The variant rs11614913 CC genotype was associated with a significantly reduced risk of gastric cancer in both sets (adjusted odds ratio [OR] = 0.78, 95% confidence interval [CI] = 0.62-0.99 for the test set and 0.64, 0.52-0.80 for the validation set) compared with the CT/TT genotypes. Furthermore, the CC genotype was associated with a significantly increased survival of gastric cancer compared with the CT/TT genotypes (adjusted hazard ratio [HR] = 0.72, 95% CI = 0.55-0.95), and the association was more prominent among patients with non-cardia gastric cancer than those with cardia gastric cancer (adjusted HR = 0.57, 95% CI = 0.40-0.83 for NCGC and 1.00, 0.65-1.53 for CGC). Our results suggested that the genetic variation of MIR196A2 may play a role in gastric cancer tumorigenesis.

Adverse prognostic impact of intratumor heterogeneous HER2 gene amplification in patients with esophageal adenocarcinoma

PURPOSE

There is increasing recognition of the existence of intratumoral heterogeneity of the human epidermal growth factor receptor (HER2), which affects interpretation of HER2 positivity in clinical practice and may have implications for patient prognosis and treatment. We determined the frequency and prognostic impact of heterogeneous HER2 gene amplification and polysomy 17 in patients with esophageal adenocarcinoma (EAC).

PATIENTS AND METHODS

HER2 amplification (by fluorescence in situ hybridization) was examined in surgical EAC specimens (n = 675). HER2 heterogeneity was defined according to consensus guidelines as gene amplification (HER2/CEP17 ratio ≥ 2.0) in more than 5% but less than 50% of cancer cells. No patient received neoadjuvant or HER2-targeted therapy. Cox models were used to assess disease-specific survival (DSS) and overall survival (OS).

RESULTS

Overall, 117 EACs (17%) demonstrated HER2 amplification, of which 20 (17%) showed HER2 heterogeneity. All HER2-heterogeneous tumors were amplified. Among HER2-amplified tumors, heterogeneous tumors had significantly higher frequency of poor histologic grade and polysomy 17. In multivariable models that included number of metastatic lymph nodes, grade, tumor stage, and polysomy 17, only HER2 heterogeneity and node number were prognostic among HER2-amplified tumors, with heterogeneity showing worse DSS (hazard ratio, 2.04; 95% CI, 1.09 to 3.79; P = .025) and OS (P = .026). Among HER2-nonamplified EACs, polysomy 17 was independently associated with worse DSS (P = .012) and OS (P = .023).

CONCLUSION

Among HER2-amplified EACs, 17% show HER2 heterogeneity, which independently predicts for worse cancer-specific death. Among HER2-nonamplified EACs, polysomy 17 is independently associated with worse survival. These novel findings demonstrate aggressive subgroups in HER2-amplified and -nonamplified EACs that have important implications for HER2 analysis and determination of benefit from HER2-targeted therapy.

The effect of XPD/ERCC2 polymorphisms on gastric cancer risk among different ethnicities: a systematic review and meta-analysis

Background

Potential xeroderma pigmentosum group D (XPD), also called excision repair cross-complimentary group two (ERCC2), Lys751Gln and Asp312Asn polymorphisms have been implicated in gastric cancer risk among different ethnicities.

Methods

We aimed to explore the effect of XPD Lys751Gln and Asp312Asn polymorphisms on the susceptibility to gastric cancer among different ethnicities through a systematic review and meta-analysis. Each initially included article was scored for quality appraisal. Desirable data were extracted and registered into databases. 13 studies were ultimately eligible for the meta-analysis of Lys751Gln polymorphism and 9 studies for the meta-analysis of Asp312Asn polymorphism. We adopted the most probably appropriate genetic model (recessive model) for both Lys751Gln and Asp312Asn polymorphisms. Potential sources of heterogeneity were sought out via subgroup and sensitivity analyses, and publication biases were estimated.

Results

Statistically significant findings were apparently noted in Asians but not in Caucasians for both XPD Lys751Gln and XPD Asp312Asn polymorphisms. A statistically significant finding could be seen in noncardia-type gastric cancer for XPD Lys751Gln polymorphism. A statistically significant finding could also be seen in high quality subgroup, small-and-moderate sample size subgroup, articles published after 2007, or PCR-RFLP genotyping subgroup for XPD Asp312Asn polymorphism.

Conclusions

Our meta-analysis indicates that XPD Gln751Gln (CC) genotype and Asn312Asn (AA) genotype may seem to be more susceptible to gastric cancer in Asian populations but not in Caucasian populations, suggesting that the two genotypes may be important biomarkers of gastric cancer susceptibility for Asian populations, the assumption that needs to be further confirmed in well-designed studies among different ethnicities. Gln751Gln (CC) genotype may also be associated with noncardia-type gastric cancer risk, which should also be confirmed among different ethnicities in the future.

Association of HER2/ErbB2 expression and gene amplification with pathologic features and prognosis in esophageal adenocarcinomas

PURPOSE

We examined the frequency, tumor characteristics, and prognostic impact of HER2 protein expression and gene amplification in patients with curatively resected esophageal adenocarcinoma (EAC).

EXPERIMENTAL DESIGN

HER2 expression was analyzed by immunohistochemistry (IHC) in surgical EAC specimens (n = 713). Gene amplification was examined by FISH in a large subset (n = 344). Most tumors were T3-4 (66%) or node positive (72%); 95% were located in the esophagus or gastroesophageal junction. No patient received neoadjuvant therapy. Cox models were used.

RESULTS

Overall, 17% of EACs were HER2 positive (i.e., IHC3(+) or IHC2(+) with amplification), with strong agreement between HER2 amplification (HER2/CEP17 ratio ≥2) and expression (κ = 0.83). HER2 positivity was significantly associated with lower tumor grade, less invasiveness, fewer malignant nodes, and the presence of adjacent Barrett's esophagus (BE). EACs with BE had higher odds of HER2 positivity than EACs without BE, independent of pathologic features [OR = 1.8 (95% CI: 1.1-2.8), P = 0.014]. Among all cases, HER2 positivity was significantly associated with disease-specific survival (DSS) in a manner that differed by the presence or absence of BE (P(interaction) = 0.0047). In EACs with BE, HER2 positivity was significantly associated with improved DSS [HR = 0.54 (95% CI: 0.35-0.84), P = 0.0065] and overall survival (P = 0.0022) independent of pathologic features, but was not prognostic among EACs without BE.

CONCLUSIONS

HER2 positivity was shown in 17% of resected EACs and associated with reduced tumor aggressiveness. EACs with BE had nearly twice the odds of being HER2 positive and, within this subgroup, HER2 positivity was independently associated with improved survival.

A meta-analysis of interleukin-10 -592 promoter polymorphism associated with gastric cancer risk

We aimed to explore the role of IL-10 -592 A/C SNP in the susceptibility to gastric cancer through a systematic review and meta-analysis. Each initially included article was scored for quality appraisal. 17 studies were eligible for the meta-analysis. We adopted the most probably appropriate genetic model (recessive model). Potential sources of heterogeneity were sought out via subgroup and sensitivity analyses, and publication biases were estimated. IL-10-592 AA genotype is associated with the reduced risk of developing gastric cancer among Asians and even apparently observed among Asians high quality subgroup, suggesting IL-10-592 AA genotype may seem to be more protective from overall gastric cancer in Asian populations. IL-10-592 AA genotype is also associated with the overall reduced gastric cancer susceptibility in persons with H. pylori infection compared with controls without H. pylori infection, suggesting IL-10-592 AA genotype may seem to be more protective from overall gastric cancer susceptibility in persons infected with H. pylori. IL-10-592 AA genotype is not associated with either pathologic subtypes (intestinal or diffuse) or anatomic subtypes (non-cardia or cardia) of gastric cancer susceptibility. Genotyping methods like direct sequencing should be highly advocated to be conducted in future well-designed high quality studies among different ethnicities or populations.

Effect of PSCA gene polymorphisms on gastric cancer risk and survival prediction: A meta-analysis

Previous studies have shown that two single-nucleotide polymorphisms (SNPs) in PSCA (rs2976392 and rs2294008) are associated with gastric cancer (GC), but the results are conflicting. Additionally, the prognostic value of PSCA gene polymorphisms for GC patients is unknown. We performed a meta-analysis using 9 eligible case-control studies to investigate the association between PSCA polymorphisms and GC risk, and additionally investigated the prognostic value of PSCA polymorphisms for GC patients with two eligible studies. The association was measured using random-effect or fixed-effect odds ratios (ORs) combined with 95% confidence intervals (CIs) according to the heterogeneity of the studies. We found that rs2294008 (dominant model: OR, 1.44; 95% CI, 1.16-1.79) and rs2976392 (dominant model: OR, 1.41; 95% CI, 0.98-2.04) polymorphisms were associated with increased risk of GC, although the association of rs2976392 was not statistically significant. For rs2294008, the associations were all consistently significant among the different subgroups stratified by ethnicity and tumor location, but not significant in intestinal or diffuse subtypes. For rs2976392, the associations were consistently significant for the intestinal, diffuse and non-cardia subtypes, but not significant for the cardia subtype. Furthermore, two eligible studies reported inverse results of PCSA in predicting the survival of GC patients (HR, 0.75; 95% CI, 0.59-0.96; and HR, 2.12; 95% CI, 1.22-3.69, respectively). In conclusion, PSCA gene polymorphisms are associated with increased risk of GC and are correlated with the prognosis of GC patients. Future studies are required to evaluate the molecular mechanisms of PSCA polymorphisms in GC and validate the prognostic value in a larger number of patients.

Interleukin-10-819 promoter polymorphism in association with gastric cancer risk

Background

Potential functional allele T/C single nucleotide polymorphism (SNP) of Interleukin 10 (IL-10) promoter -819 (rs1800871) has been implicated in gastric cancer risk. We aimed to explore the role of T/C SNP of IL-10 -819 in the susceptibility to gastric cancer through a systematic review and meta-analysis.

Methods

Each initially included article was scored for quality appraisal. Desirable data were extracted and registered into databases. 11 studies were ultimately eligible for the meta-analysis of IL-10 -819 T/C SNP. We adopted the most probably appropriate genetic model (recessive model). Potential sources of heterogeneity were sought out via subgroup and sensitivity analyses, and publication biases were estimated.

Results

IL-10 -819 TT genotype is associated with the overall reduced gastric cancer risk among Asians and even apparently observed among high quality subgroup Asians. IL-10-819 TT genotype is not statistically associated with the overall reduced gastric cancer susceptibility in persons with H. pylori infection compared with controls without H. pylori infection. IL-10 -819 TT genotype is reversely associated with diffuse-subtype risk but not in intestinal-subtype risk. IL-10 -819 TT genotype is not reversely associated with non-cardia or cardia subtype gastric cancer susceptibility.

Conclusions

IL-10 -819 TT genotype seems to be more protective from gastric cancer in Asians. Whether IL-10 -819 TT genotype may be protective from gastric cancer susceptibility in persons infected with H. pylori or in diffuse-subtype cancer needs further exploring in the future well-designed high quality studies among different ethnicity populations. Direct sequencing should be more used in the future.

A meta-analysis of interleukin-8 -251 promoter polymorphism associated with gastric cancer risk

Background

Potential functional allele A/T single nucleotide polymorphism (SNP) of Interleukin 8 (IL-8) promoter -251has been implicated in gastric cancer risk.

Methods

We aimed to explore the role of A/T SNP of IL-8 -251 in the susceptibility to gastric cancer through a systematic review and meta-analysis. Each initially included article was scored for quality appraisal. Desirable data were extracted and registered into databases. Eighteen studies were ultimately eligible for the meta-analysis of IL-8 - 251 A/T SNP. We adopted the most probably appropriate genetic model (codominant model). Potential sources of heterogeneity were sought out via stratification and sensitivity analyses, and publication biases were estimated.

Results

Between IL-8 -251 AA genotype with gastric cancer risk, statistically significant association could be noted with overall gastric cancer, evidently noted in Asians, witnessed in high quality subgroup, and apparently noted in intestinal-type gastric cancer.

Conclusions

Our meta-analysis indicates that IL-8 -251 AA genotype is associated with the overall risk of developing gastric cancer and may seem to be more susceptible to overall gastric cancer in Asian populations. IL-8 -251 AA genotype is more associated with the intestinal-type gastric cancer. IL-8 -251 AA genotype is not associated with Helicobacter Pylori infection status in our meta-analysis.

Impact

The analyses suggest that IL-8 -251 AA genotype may be an important biomarker of gastric cancer susceptibility for Asians, especially for Chinese Han population, the assumption that needs to be further confirmed in future well-designed studies in China.

Prognostic impact of body mass index stratified by smoking status in patients with esophageal adenocarcinoma

PURPOSE

Given that smoking affects body mass index (BMI) and survival, stratification by smoking status may be required to determine the true prognostic impact of BMI. Although obesity increases risk for developing esophageal adenocarcinoma (EAC), the prognostic influence of obesity and its potential modification by smoking status is unknown in this disease.

PATIENTS AND METHODS

All patients (N = 778) underwent potentially curative esophagectomy. BMI was calculated using measured height and weight at surgery and categorized as obese (≥ 30 kg/m(2)), overweight (25 to 29.9 kg/m(2)), or normal (18.5 to 24.9 kg/m(2)). Cigarette smoking was categorized as never or ever. The association of BMI with disease-specific survival (DSS), disease-free survival (DFS), and overall survival (OS) was determined by Cox regression.

RESULTS

Excess BMI was significantly associated with DSS in a manner that differed substantially by smoking status (P for interaction = .023). Among never smokers, obesity was significantly associated with adverse DSS (hazard ratio [HR] = 2.11; 95% CI, 1.31 to 3.43; P = .002), DFS (HR = 2.03; 95% CI, 1.30 to 3.18; P = .002), and OS (HR = 1.97; 95% CI, 1.24 to 3.14; P = .004), as compared with normal weight, after adjusting for covariates. By contrast, among ever smokers, obesity was not prognostic, and overweight status was significantly associated with favorable survival in univariate, but not multivariate, analysis.

CONCLUSION

Obesity among never smokers was independently associated with two-fold worsening of DSS, DFS, and OS after surgery for EAC, after adjusting for known prognostic factors. These data, in one of the largest reported resected EAC cohorts, are the first to show an adverse prognostic impact of obesity in EAC.

Lymph node metastases and prognosis in oesophageal carcinoma--a systematic review

Oesophageal cancer is the 7th most common cause of cancer-related death in the developed world and the incidence of oesophageal adenocarcinoma is now the fastest growing of any gastrointestinal cancer. Lymph node involvement is the single most important prognostic factor in oesophageal cancer. Imaging to determine the extent of lymph node involvement and plan treatment often requires a combination of modalities to avoid under-staging. The 7th edition of the staging system released by the International Union Against Cancer (IUCC) has stratified lymph node involvement according to the number of lymph nodes involved and redefined its groupings for location of metastatic lymph node involvement. This review discusses the prognostic and treatment implications of these modifications and explores micrometastatic lymph node involvement, capsular infiltration and lymph node ratio as possible additions to the staging system.

A meta-analysis of CDH1 C-160A genetic polymorphism and gastric cancer risk

We explored the role of the C-160A single-nucleotide polymorphism (SNP) of CDH1 in susceptibility to gastric cancer through a systematic review and meta-analysis. Fourteen studies were included, the original groups collapsed, and re-grouped in accordance with the most appropriate genetic model. Potential sources of heterogeneity were sought out via subgroup analyses and sensitivity analyses, and publication biases were estimated. No significant association of C-160A was found with the overall risk of developing gastric cancer, but the apparently opposite tendency was noted between Caucasians and Asians, and a statistically significant association was found among Asians. The seemingly opposite tendency of associations was also seen between noncardia and cardia types or between sporadic diffuse and intestinal types of gastric cancer, but no statistically significant findings were noted. Genotyping techniques, sample size, quality appraisal scores, or article publication time did not constitute the source of heterogeneity across studies; and no publication biases were found in our meta-analysis.

X-ray repair cross-complementing group 1 (XRCC1) genetic polymorphisms and gastric cancer risk: A HuGE review and meta-analysis

The authors performed a systematic review and meta-analysis of associations of the x-ray repair cross-complementing 1 gene (XRCC1) single nucleotide polymorphisms (SNPs) Arg194Trp, Arg280His, and Arg399Gln with gastric cancer risk, based on eligible studies retrieved from electronic databases for the period January 2000-December 2009. Ultimately, 12, 6, and 3 studies were found to be eligible for meta-analyses of Arg399Gln, Arg194Trp, and Arg280His, respectively. Regrouping was adopted in accordance with the most probably appropriate genetic models. Potential sources of heterogeneity were sought out. For overall gastric cancer, the pooled odds ratios for Arg399Gln, Arg194Trp, and Arg280His were 1.04 (95% confidence interval (CI): 0.90, 1.20; P = 0.572), 0.83 (95% CI: 0.68, 1.01; P = 0.059), and 1.18 (95% CI: 0.92, 1.50; P = 0.194), respectively. After stratification of the Arg399Gln SNP data by anatomic type (cardia vs. noncardia), the pooled odds ratio was 1.07 (95% CI: 0.84, 1.37; P = 0.568). The authors conclude that the 3 SNPs evaluated are not associated with risk of gastric cancer. The Arg399Gln SNP is not associated with the cardia type of gastric cancer. Evidently, the heterogeneity regarding the Arg399Gln SNP across studies is not explained by ethnicity, genotyping technique, sample size, or date of publication.

Two genetic variants in prostate stem cell antigen and gastric cancer susceptibility in a Chinese population

Genetic factors play important roles in pathogenesis of human cancer. A recent genome-wide association study (GWAS) linked two single nucleotide polymorphisms (SNPs) in prostate stem cell antigen (PSCA), rs2294008C>T and rs2976392G>A, to risk of diffuse-type of gastric cancer in Japanese and Korean populations. We hypothesized that these two SNPs are also associated with risk of gastric cancer in Chinese population. We examined genotypes and haplotypes of PSCA, rs2294008C/T and rs2976392G/A in 716 patients with cardia gastric carcinoma (CGC), 1020 patients with noncardia gastric carcinoma (NCGC), and 1020 controls. We found that individuals with at least one copy of the rs2294008T allele (CT or TT genotype) had an elevated risk for developing NCGC compared with those without this allele (OR = 1.35, 95% CI = 1.13-1.61). Individuals with at least one copy of the rs2976392A allele (GA or AA genotype) had nonsignificantly increased risk for NCGC compared with those without this allele (OR = 1.20, 95% CI = 1.01-1.43). Stratification analysis showed that the increased risk associated with the SNPs was restricted in female subjects. Moreover, the rs2294008T and rs2976392A allele carriers were predisposed to developing poorly differentiated and high stage NCGC at diagnosis. However, no such association was detected for CGC. In addition, we observed considerably lower allelic and genotype frequencies of these genetic variants in Chinese population compared with Japanese and Korean populations. These findings are in general consistent with previous GWAS and suggest that PSCA may play a role in the development of NCGC in Chinese population.

Polymorphisms of XRCC1 gene and risk of gastric cardiac adenocarcinoma

X-ray repair cross complementing 1 (XRCC1) protein plays an important role in base excision repair. Single nucleotide polymorphisms (SNPs) in XRCC1 gene may affect DNA repairing ability and genetic susceptibility to cancer. This study was designed to investigate the correlation of XRCC1 Arg194Trp Arg280His and Arg399Gln SNPs with the risk of gastric cardiac adenocarcinoma (GCA). Genotypes were analyzed by polymerase chain reaction-restriction fragment length polymorphism assay in 455 patients with GCA and 650 age and sex-matched controls. We did not find any significant difference in allele and genotype distributions of Arg194Trp Arg399Gln between the groups (P > 0.05). However, a significant increase in GCA risk was seen among smokers if they carried at least one XRCC1 280His (Arg280His + His280His) genotype (odds ratio = 1.59, 95%confidence interval = 1.01-2.51) compared with smokers not carrying these genotype. Our results indicated that XRCC1 Arg194Trp and Arg399Gln SNPs might not be associated with the risk of GCA. However, smokers with His allele at codon 280 had a significantly increased risk of GCA.

Proposal for a new definition of true cardia carcinoma

BACKGROUND AND OBJECTIVES

It remains controversial whether cardia carcinoma should be categorized and treated as esophageal cancer or gastric cancer. The purpose of this study was to develop a reasonable definition of cardia carcinoma.

METHODS

Patients with Siewert type II carcinomas were divided into two subgroups: 25 patients with a tumor center within 1 cm of the esophagogastric junction (EGJ) (type IIA) and 22 patients with tumor center 1-2 cm aboral of the EGJ (type IIB). Patients with subcardia carcinomas, 40 with invasion to the EGJ (type III) and 110 without (type IIIe-), were used as controls.

RESULTS

The patients with type IIB carcinomas showed no different characteristics from those with type III or type IIIe- carcinomas, except for the stage of the disease. On the other hand, those with type IIA carcinomas were associated with a higher male/female ratio, higher incidences of elevated appearance, differentiated histology, and mediastinal node metastasis, and a significantly lower survival rate as compared with patients with subcardia carcinomas. Multivariate survival analysis revealed that type IIA is a significant prognostic determinant, but that type IIB is not.

CONCLUSION

Type IIA carcinomas should be treated as true cardia carcinoma; type IIB as subcardia carcinoma. Our results should be confirmed by a prospective study.

Prognostic factors in adenocarcinoma of the esophagus or gastroesophageal junction

The incidence of adenocarcinoma of the esophagus is rising rapidly in Western Europe and North America. It is an aggressive disease with early lymphatic and hematogenous dissemination. TNM cancer staging systems predict survival on the basis of the anatomic extent of the tumor. However, the adequacy of the current TNM staging system for adenocarcinoma of the esophagus or gastroesophageal junction (GEJ) is questioned repeatedly. Numerous prognostic factors have been described, but are not included in the TNM system. This review describes clinical parameters, aspects of operative technique, response to preoperative chemoradiotherapy therapy, complications and established pathologic determinants found in the resection specimen that have a prognostic impact. Furthermore, their potential application in the clinical setting in patients with adenocarcinoma of the esophagus or GEJ is discussed. Future directions to improve staging systems are given.

Clinicopathologic comparison of Siewert type II and III adenocarcinomas of the gastroesophageal junction

BACKGROUND

Since Misumi et al. and Siewert proposed a new classification for carcinoma of the gastroesophageal junction (GEJ), few surgical studies using these criteria have been reported from Eastern countries. Siewert type II adenocarcinomas are managed using general rules for either gastric or esophageal cancer. We set out to determine whether type II adenocarcinoma is a distinct clinical entity requiring a more specific treatment plan.

METHODS

Among 125 Japanese patients who underwent resection of adenocarcinoma of the GEJ (type I, 2; type II, 44; type III, 79), 101 who underwent R0 resections (type II, 40; type III, 61) were analyzed to evaluate surgical results and compare clinicopathologic factors.

RESULTS

Barrett's epithelium was recognized in two patients with type II adenocarcinoma. Type II differed significantly from type III in higher prevalence of Borrmann macroscopic type 2, more frequent lymph node metastasis (58% vs. 34%), higher metastatic rate to lower mediastinal lymph nodes (13%), increased risk of hepatic recurrence, and lower 5-year survival after R0 resection (67.4% vs. 87.1%).

CONCLUSIONS

Clinicopathologic differences were evident between type II and III adenocarcinomas. Siewert type II adenocarcinoma differs sufficiently to be considered a clinical entity distinct and independent from type III.

The histological appearance of oesophageal adenocarcinoma—an analysis based on 215 resection specimens

The current study was performed to determine whether the histopathological appearance of oesophageal adenocarcinoma (AC) differs significantly from that of cardiac or gastric AC. Therefore, HE-stained slides of 215 primarily resected oesophageal AC, 108 cardiac and 184 gastric AC were classified according to a variety of clinico-pathologic parameters. According to Lauren's classification, oesophageal AC (1.4%) less frequently belonged to the diffuse type than cardiac (2.8%) and gastric AC (23.9%; p<0.0001). Tubular and papillary AC, as defined by the WHO classification, were more frequent among oesophageal (94.4%) than among cardiac (87.0%) and gastric AC (59.2%; p<0.0001). Solid carcinomas, according to Carneiro's classification, were less frequent among oesophageal (2.8%) than among cardiac (10.2%) and gastric AC (9.2%; p<0.0001). Oesophageal AC were graded more frequently G1/G2 (53.9%) than cardiac (30.6%) and gastric AC (27.7%; p<0.0001). Among oesophageal AC, Lauren's classification (p=0.0067), Carneiro's classification (p=0.0170), tumour grade (p=0.0005), lymphatic vessel invasion (p<0.0001) but not WHO classification were histological predictors of postoperative survival. In conclusion, oesophageal AC displays the same histological spectrum as cardiac and gastric AC. However, the relative proportion of differentiated, gland-forming carcinomas is significantly more frequent in the oesophagus than in the cardia and in the stomach.

[Adenocarcinoma of the esophagogastric junction: prognostic factors and results of primary surgery]

INTRODUCTION

The incidence of adenocarcinoma of the esophagogastric junction (AEG) is increasing worldwide, and classification systems and resection procedures are being controversially discussed.

METHODS AND PATIENTS

We report on 225 AEG patients undergoing primary resection in our unit (1986-2000) with a special focus on perioperative morbidity, mortality, and long-term prognosis under consideration of the AEG type (Siewert classification) and operative procedure performed (subtotal esophagectomy with proximal gastric resection in AEG I, total gastrectomy with distal esophageal resection in AEG II and AEG III).

RESULTS

Types I, II, and III carcinomas were found in 32%, 42%, and 26% of the patients, respectively, with R(0) resections in 65%, 69%, and 51% ( P=0.039). The overall 5-year survival rates were 29%, 31%, and 14% ( P=0.068), respectively; in R(0)-resected patients, they were 40%, 41%, and 27% ( P=0.771). In univariate analysis, the TNM classification ( P<0.001), R classification ( P<0.001), and tumor stage ( P<0.001) were relevant prognostic factors. In multivariate analysis, only the R classification ( P=0.003), LN ratio ( P=0.012), and N stage ( P=0.027) were independent prognostic factors. In 35 of 177 patients resected with curative intent, R(0) resections could not be achieved, mainly because of residual tumor in the circumferential plane (22/35=63%). Only in 37% of cases (13/35) was the R(1) situation due to exclusive positive oral or aboral resection margins. Therefore, in only 7% of all patients resected with curative intent (13/177) did the question arise of whether the R(1) resection could have been avoided by a different surgical approach. Surgical, pulmonary, and cardiac complications were found in 33%, 26%, and 10%, respectively. The mortality within 30 days was 4%.

CONCLUSIONS

Failure of R(0) resection in patients treated with curative intent is mostly caused by residual tumor in the circumferential plane. Therefore, different surgical approaches with varying oral and aboral resection margins are of minor importance for reducing the frequency of R(1) resections. Downstaging of tumors by neoadjuvant treatment may increase the R(0) resection rate.

Trends in oesophago-gastric surgery in Scotland

BACKGROUND

The last twenty years have seen significant changes in both the incidence and treatment of gastro-oesophageal disorders as well as a process of subspecialisation in general surgery. The aim of this study is to identify the changes in gastro-oesophageal surgery in Scotland during this period.

METHODS

A retrospective analysis of three years of data, taken over a 20-year period (1977, 1987 and 1997) obtained from the Information and Statistics Division of the Scottish National Health Service, examining the number of patients with oesophageal cancer, gastric cancer and gastro-oesophageal reflux disease (GORD) treated by general and thoracic surgeons.

RESULTS

There was a significant increase (p=0.001, chi2) in the number of patients with oesophageal cancer (2.52-fold) and gastric cancer (1.4-fold) treated by general compared with thoracic surgeons. Since 1977, the overall operability for oesophageal cancer has remained unchanged, while a significant decrease in the overall operability of gastric cancer was noted (p<0.001, chi2). There was a 3-fold increase in the incidence of GORD with a significant increase (p<0.001, chi2) of those treated surgically. Since 1977, there has also been a significant shift of workload from thoracic to general surgical units.

CONCLUSIONS

Scotland has seen a consistent increase in the surgical workload generated by gastro-oesophageal malignancies over the last three decades without any improvement in the operability rate. Surgically treated GORD has also increased, probably due to the introduction of minimally invasive techniques. These trends have implications on healthcare planning, resource allocation and surgical training. Appropriate resources and trainees should follow the patients to those units carrying out this activity. Further centralisation of these services is likely to follow.

Comparison of comorbidity prevalence in oesophageal and gastric carcinoma patients: a population-based study

OBJECTIVE

We investigated the distribution of serious comorbidity in patients with newly diagnosed oesophageal and gastric cancer between 1993 and 2001. Our special interest was comparing distal oesophageal and gastric cardia adenocarcinoma patients since a common origin of these tumours has been suggested.

METHODS

Data on comorbidity (previous cancers, chronic obstructive pulmonary diseases, cardiovascular and cerebrovascular diseases, hypertension, ulcerative digestive tract diseases, liver diseases and diabetes) were derived from a population-based database in The Netherlands to compare risk factor profiles for 479 oesophageal squamous cell carcinomas, 339 distal oesophageal adenocarcinomas, 570 cardia adenocarcinomas and 1965 subcardia cancers.

RESULTS

A comparable age and gender distribution was shown in distal oesophageal and cardia adenocarcinoma patients. After adjustment for age and gender, only the prevalence of previous cancers differed between adenocarcinomas of distal oesophagus and cardia [more frequent in distal oesophageal adenocarcinoma patients, odds ratio (OR) = 1.84, P = 0.01]. Ulcerative and liver diseases were more prevalent in oesophageal squamous cell carcinoma patients as compared with distal oesophageal adenocarcinoma patients (OR = 1.90, P = 0.02 and OR = 8.82, P = 0.04, respectively), whereas diabetes was more prevalent in the latter (OR = 0.56, P = 0.03). Cardia adenocarcinoma patients significantly more often had hypertension as compared with subcardia cancer patients (OR = 1.53, P = 0.001), whereas the latter more often suffered from previous cancers and ulcerative diseases (OR = 0.54, P = 0.0009 and OR = 0.25, P < 0.0001, respectively).

CONCLUSIONS

In terms of comorbidity at diagnosis, cardia adenocarcinoma patients resemble distal oesophageal adenocarcinoma patients rather than gastric subcardia carcinoma patients, with likewise equal age and gender distribution.

Marked multi-ethnic variation of esophageal and gastric cardia carcinomas within the United States

OBJECTIVE

No prior studies have contrasted esophageal and gastric cardia carcinoma incidence rates among multiple ethnicities. We evaluated whether these adjacent cancers differ; such detailed demographic analyses would inform risk factor, screening, and intervention studies.

METHODS

We contrasted incidence rates and temporal trends from the Surveillance, Epidemiology, and End Results (SEER) cancer registry data between 1992 and 1998 for five groups: non-Hispanic whites (Caucasians), white Hispanics (Hispanics), blacks, Asians/Pacific Islanders (Asians/PI), and Native Americans (NA).

RESULTS

Caucasian males' esophageal adenocarcinoma rate (4.2 per 100,000 population/yr) was double that of Hispanics and four-fold higher than those of blacks, Asians/PI, and NA (p < 0.01). Female rates were much lower than male rates for all ethnicities. Similar to esophageal adenocarcinoma, cardia adenocarcinoma rates were highest in Caucasian males (3.4 per 100,000 population/yr); however, the ethnic differences were much less and female rates were comparable for all almost all ethnicities (range 0.6-0.7 per 100,000 population/yr) except NA. Esophageal adenocarcinoma incidence rates increased significantly only in Caucasians (males 5.6%/yr, females 9%/yr; p < 0.05) and cardia cancer rates did not increase for any ethnicity during this period. In contrast, esophageal squamous cell carcinoma incidence rates were highest in blacks (8.8 per 100,000 population/yr) and Asians/PI (3.9 per 100,000 population/yr) and rates were stable or declined for all ethnicities between 1992 and 1998.

CONCLUSIONS

Esophageal and cardia carcinoma incidence rates vary much more markedly by ethnicity and gender than previously reported and the two sites differ from each other. Current putative risk factors do not adequately explain these large differences. These data have implications for risk factor, screening, and intervention studies.

Three different subsite classification systems for carcinomas in the proximity of the GEJ, but is it all one disease?

BACKGROUND AND AIM

Currently there are three different subsite classification systems for carcinomas in the region of the gastroesophaeal junction (GEJ), namely ICD-O, Munich and Liverpool. The aim of the present study was to compare clinicoepidemiological, pathological and molecular features of adenocarcinomas in the proximity of the GEJ, classified according to their position with respect to the GEJ initially, and then classified according to ICD-O, Munich and Liverpool classifications.

METHODS

Forty-seven adenocarcinomas in the proximity of the GEJ were subdivided into groups 1 (exclusively within esophagus), 2 (mainly within esophagus but extending distally across GEJ), 3 (equally present in esophagus and stomach) or 4 (mainly in stomach but extending proximally across GEJ), and analysis of their clinicoepidemiological, pathological and molecular features was performed. Molecular characterization included loss of heterozygosity (LOH) and microsatellite instability analyses.

RESULTS

Group 3 carcinomas were younger than other carcinomas in the proximity of the GEJ, but otherwise these carcinomas were similar in their clinicoepidemiological, pathological and molecular features. There were no significant differences between esophageal (groups 1 and 2) and gastric (groups 3 and 4) carcinomas as classified by ICD-O. Munich types I (groups 1 and 2), II (group 3) and III (group 4) carcinomas of the GEJ were also similar. LOH at the site of the Rb tumor suppressor gene and at 17p11.1-p12 was more common in GEJ (groups 2, 3 and 4) than lower third (group 1) esophageal carcinomas classified according to the Liverpool system.

CONCLUSION

Overall, adenocarcinomas of the lower esophagus and adenocarcinomas involving the GEJ have similar clinicoepidemiological, pathological and molecular features no matter which subsite classification is used, adding further evidence that they represent the same disease.

The pattern of recurrence of adenocarcinoma of the oesophago-gastric junction

Knowledge of the pattern of recurrence of surgically treated cases of adenocarcinoma of the oesophago-gastric junction is important both for better understanding of their biological nature and for future strategic planning of therapy. The aim of this study is to demonstrate and compare the pattern of dissemination and recurrence in patients with Type I and Type II adenocarcinoma of oesophago-gastric junction. A prospective audit of the clinico-pathological features of patients who had undergone surgery with curative intent for adenocarcinoma of oesophago-gastric junction between 1991 and 1996 was undertaken. Patients were followed up by regular clinical examination. Clinical evaluation was supported by ultrasound, computerised tomography, radio-isotope bone scan, endoscopy and laparotomy each with biopsy and histology where appropriate. One hundred and sixty-nine patients with oesophago-gastric junction tumours (94 Type I and 75 Type II) have been followed up for a median of 75.3 (57-133) months. One hundred and three patients developed proven recurrent disease. The median time to recurrence was 23.3 (14.2-32.4) months for Type I and 20.5 (11.6-29.4) for Type II cancers. The most frequent type of recurrence was haematogenous (56% of Type I recurrences and 54% of Type II) of which 56% were detected within 1 year of surgery. The most frequent sites were to liver (27%), bone (18%) brain (11%) and lung (11%). Local recurrence occurred in 33% of Type I cancer and 29% of Type II recurrences. Nodal recurrence occurred in 18 and 25% of Type I and Type II cancer recurrences, most frequently to coeliac or porta hepatis nodes (64%). Only 7% of Type I and 15% of Type II cancer recurrences were by peritoneal dissemination. Type I and Type II adenocarcinoma of the oesophago-gastric junction have a predominantly early, haematogenous pattern of recurrence. There is a need to better identify the group of patients with small metastases at the time of diagnosis who are destined to develop recurrent disease in order that they may be spared surgery and those with micro metastases in order that they can be offered multi-modality therapy including early post operative or neo-adjuvant chemotherapy.

[Target volume in radiotherapy of gastric adenocarcinoma]

The spread of gastric adenocarcinoma may follow three main patterns: hematogenic, lymphatic and intraperitoneal. A GTV should be considered in preoperative or exclusive radiation therapy. After non-radical surgery, a "residual GTV" will be defined with the help of the surgeon. The CTV encompasses three intricated volumes. a) A "tumor bed" volume. After radical surgery, local recurrences appear as frequent as distant metastases. The risk depends upon the depth of parietal invasion and the nodal status. Parietal infiltration may extend beyond macroscopic limits of the tumor, especially in "linitis plastica". Therefore this volume will include: the tumor and the remaining stomach or their "bed of resection", a part of the transverse colon, the duodenum, the pancreas and the truncus of the portal vein. In postoperative RT, this CTV also includes the jejuno-gastric or jejuno-esophageal anastomosis. b) A peritoneal volume. For practical purposes, two degrees of spread must be considered: (1) contiguous microscopic extension from deeply invasive T3 and T4 tumors, that remain amenable to local sterilization with doses of 45-50 Gy, delivered in a CTV including the peritoneal cavity at the level of the gastric bed, and under the parietal incision; (2) true "peritoneal carcinomatosis", with widespread seeds, where chemotherapy (systemic or intraperitoneal) is more appropriate. c) A lymphatic volume including the lymph node groups 1 to 16 of the Japanese classification. This volume must encompass the hepatic pedicle and the splenic hilum. In proximal tumors, it is possible to restrict the lower part of the CTV to the lymphatic volume, and therefore to avoid irradiation of large intestinal and renal volumes. In distal and proximal tumors, involvement of resection margins is of poor prognosis--a radiation boost must be delivered at this level. The CTV in tumors of the cardia should encompass the lower part of the thoracic esophagus and the corresponding posterior mediastinum. In tumors invading the distal esophagus, a more complete coverage of mediastinal lymph nodes should be considered, especially in patients in good general condition. In tumors of the gastric fundus, most of the left hemidiaphragm should be included, as well as the spleen and its hilum (or their resection bed). In proximal tumors without involvement of the lesser curvature, a full coverage of the hepatic pedicle is not necessary. In contrast, for distal tumors, the hepatic pedicle and the hepatoduodenal ligament should be included whereas the splenic area could be spared.

CONCLUSION

Planning the treatment of gastric cancer remains difficult; target volumes must be customized by experienced radiation oncologists according to tumoral and clinical situation.

Pathology of early invasive adenocarcinoma of the esophagus or esophagogastric junction: implications for therapeutic decision making

BACKGROUND

As an alternative to surgical resection, endoscopic treatment modalities are being explored for the treatment of patients with early esophageal carcinoma. This study aimed to evaluate patterns of local growth and regional dissemination of early adenocarcinoma of the esophagus or esophagogastric junction, as these pathologic features may contribute to rational therapeutic decision making.

METHODS

Among 173 patients who underwent esophageal resection for invasive adenocarcinoma (1993-1998), 32 (19%) had early stage cancer (pT1). Clinical records, pathology reports, and original slides of the surgically resected esophagus were reviewed in each case.

RESULTS

In 12 patients tumor invasion was limited to the mucosa, whereas in 20 patients the tumor showed infiltration of the submucosa. All cancers were associated with intestinal metaplasia. Areas of high grade dysplasia accompanied 27 of the 32 cancers (84%). Intramucosal cancer had no lymph node metastasis but presented as multifocal disease in 42% of cases and extended under preexisting squamous mucosa in 17% of cases. In submucosal cancer, lymph node metastases were present in 30% of cases. Disease specific 3-year survival for patients with intramucosal cancer was 100% and for those with submucosal cancer 82% (P = not significant).

CONCLUSIONS

Based on the local growth pattern of intramucosal adenocarcinoma of the esophagus or esophagogastric junction, endoscopic treatment of patients with this disease should be applied with caution. For submucosal carcinoma, surgery is the mainstay of treatment, as lymph node metastasis is frequently present. Both subclassifications of early cancer show a favorable outcome after esophagectomy.

Three-field lymphadenectomy and pattern of lymph node spread in T3 adenocarcinoma of the distal esophagus and the gastro-esophageal junction

OBJECTIVE

Lymph node metastasis in carcinoma of the esophagus and the gastro-esophageal junction is often underestimated by clinical staging. It is the aim of this study to provide support to the fact that three-field lymphadenectomy leads to a better pathological staging also in adenocarcinoma.

METHODS

The pattern of lymph node metastasis in adenocarcinoma of the gastro-esophageal junction (GEJ) and the distal esophagus was charted in a prospective way by using a database. An analysis was performed with regard to lymphatic spread in T3, N+ adenocarcinomas of the distal esophagus and the GEJ junction, which were treated with a radical resection including a three-field lymphadenectomy. Out of 324 patients with adenocarcinoma of the esophagus and GEJ, we selected a group of 37 patients with an adenocarcinoma T3, N+ of the distal (n = 17) or GEJ junction (n = 20), treated with a radical resection and three-field lymphadenectomy ( > 25 lymph nodes resected).

RESULTS

In total, 2240 lymph nodes were removed, with a mean of 59.5 per patient. In the GEJ group the ratio of positive nodes was 15.9, in the distal 1/3 group this ratio was 12.7%. Abdominal lymph nodes were positive in all GEJ tumors and in 70% of the distal third carcinomas. Thoracic lymph nodes were positive in 40% of GEJ tumors, and 70.6% of the distal group. Cervical lymph nodes were positive in 20% of the GEJ tumors and in 35.3% of the distal tumors. In six patients only right-sided cervical nodes were affected. Three patients in the GEJ group had positive lymph nodes in the neck without any involvement of thoracic lymph nodes.

CONCLUSIONS

(1) Three-field lymphadenectomy improves accuracy of staging. (2) Cervical nodes are frequently involved. (3) Especially in tumors of the GEJ there is an important skipping phenomenon, i.e. positive lymph nodes in the neck in the absence of involvement of thoracic nodes. (4) Clinical staging remains deficient in regard to lymph node metastasis, especially cervical nodes. (5) The frequent unforeseen involvement of cervical lymph nodes in adenocarcinoma of the distal esophagus and GEJ tumors makes the interpretation of results of induction chemoradiotherapy questionable. (6) For the same reason, cervical lymph nodes should be included in the radiation field in case of induction chemoradiotherapy. (7) The similar pattern of lymph node involvement suggests similar oncological behavior of adenocarcinoma of the distal esophagus and the GEJ, questioning the actual TNM classification of these tumors as gastric carcinomas.

Prognostic value of Laurén classification and c-erbB-2 oncogene overexpression in adenocarcinoma of the esophagus and gastroesophageal junction

BACKGROUND

The prognostic value of the Laurén classification and of c-erbB-2 oncogene overexpression has been described for gastric cancer. The aim of this study was to investigate the clinical significance of these factors in adenocarcinoma of the esophagus and/or gastroesophageal junction (GEJ).

METHODS

Forty-one adenocarcinomas of the esophagus and/or GEJ were reviewed for tumor stage, lymph node status, Laurén classification, and c-erbB-2 overexpression, as assessed by immunohistochemical analysis.

RESULTS

According to the Laurén classification, tumors were classified as intestinal-, mixed-, or diffuse-type (54%, 32%, and 15%, respectively). Diffuse-type tumors were associated with a significantly worse prognosis than were intestinal-type tumors (P = .018; log-rank test). The prognostic value of the Laurén classification was independent of stage (P = .048; Cox regression model). Overexpression of c-erbB-2 was detected in 24% of the tumors and was present exclusively in intestinal-type tumors and in intestinal-type areas of mixed-type tumors. Ten of the 30 stage III/IV tumors (33%) were c-erbB-2-positive, whereas none of the 11 stage I/II tumors (0%) overexpressed the oncogene product (P = .04; Fisher exact test). The prognostic value of c-erbB-2 overexpression was not independent of stage (P = .7; Cox regression model).

CONCLUSIONS

(1) The Laurén classification is an independent prognostic factor in adenocarcinoma of the esophagus and GEJ. (2) c-erbB-2 overexpression is limited to (areas of) intestinal-type tumors, indicating that intestinal- and diffuse-type tumors differ oncogenetically. (3) c-erbB-2 overexpression is associated with the stage of disease, indicating that it is a late event during tumor progression.

Adenocarcinomas of the distal oesophagus and gastric cardia are one clinical entity. Rotterdam Oesophageal Tumour Study Group

BACKGROUND

Adenocarcinomas of the distal third of the oesophagus and the gastric cardia have similar characteristics but different staging criteria are being used. In the present study the question is addressed whether these tumours should be regarded and staged as one clinical entity.

METHODS

From January 1987 to January 1997, 252 patients with an adenocarcinoma of the oesophagus (n = 111) or gastric cardia (n = 141) underwent transhiatal resection. Pathology, pathological tumour node metastasis (pTNM) stage and survival were analysed retrospectively, and a comparison was made between tumours of the oesophagus and gastric cardia.

RESULTS

Barrett's epithelium was diagnosed in 54 per cent of oesophageal adenocarcinomas compared with 13 per cent of adenocarcinomas of the gastric cardia (P < 0. 001). Oesophageal carcinomas had a more favourable pT stage, fewer positive locoregional lymph nodes (pN1-2 56 versus 62 per cent; P = 0.3), but more distant metastases accounted for by positive lymph nodes around the coeliac axis (pM1 19 versus 4 per cent; P < 0.001). Five-year overall survival (26 versus 27 per cent; P = 0.9) and survival according to tumour stage were no different between the groups. Multivariate analysis showed that the location of the primary tumour was not an independent prognostic factor.

CONCLUSION

Adenocarcinomas of the distal oesophagus and gastric cardia should be regarded as one clinical entity. Uniform staging criteria for both malignancies are recommended.

Proposed revision of the staging classification for esophageal cancer

OBJECTIVES

This study analyzed survival with respect to lymph node involvement to develop a new staging system for patients with esophageal cancer that accurately reflects prognosis.

METHODS

The records of patients undergoing resection of primary esophageal cancer from 1989 to 1993 were reviewed. The data collected included patient age and sex, tumor histologic characteristics and location, the use of preoperative or postoperative radiation and chemotherapy, the type of resection, the depth of tumor invasion, the number and location of benign and malignant lymph nodes in the resected specimen, the disease status at last follow-up, and the first site of relapse. With an anatomically specific lymph node map, tumors designated in the current American Joint Committee on Cancer system as M1 because of extensive lymph node metastases were reclassified as N2, reserving the M1 category for visceral metastases. Survival was analyzed by the Kaplan-Meier method, and prognostic factors were assessed by log-rank and Cox regression analyses.

RESULTS

There were 216 patients (159 men, 57 women) with a median age of 63.5 years. Adenocarcinoma of the distal esophagus or gastroesophageal junction was the most common tumor (127 patients, 59%) and Ivor Lewis esophagogastrectomy was the most frequently performed operation. Both lymph node location (N1 versus N2) and number (0 vs 1 to 3 vs 4 or more) significantly influenced survival.

CONCLUSIONS

A new staging system that adds an N2 M0 descriptor and reclassifies stage groupings reflects prognosis more accurately than does the current American Joint Committee on Cancer staging system. The number of positive lymph nodes is also an important stratification factor.

Tumors of the esophagogastric junction. Long-term survival in relation to the pattern of lymph node metastasis and a critical analysis of the accuracy or inaccuracy of pTNM classification

From 1983 to 1989, 95 patients with carcinoma of the esophagogastric junction underwent resection. Overall hospital mortality rate was 6.2% (6/95). Actuarial survival analysis showed 5- and 10-year survivals of 33% and 31%, respectively. Five- and 10-year survivals of patients according to TNM stages were as follows: stage I (n = 13), 90% at both 5 and 10 years; stage II (n = 13), 70% at both intervals; stage III (n = 28), 28% at both intervals; and stage IV (n = 40), 11% and 8%, respectively. For patients with undiseased nodes (n = 26), 5- and 10-year survivals were 72% and 72%, compared with 18% and 16% for patients with diseased nodes (n = 68; p < 0.005). In patients who had involvement of both the abdominal and thoracic lymph nodes (n = 28), 5- and 10-year survivals were 13% and 13%, compared with 26% and 26% if metastases were confined to the abdomen (n = 37; p > 0.05). Grouping patients with diseased intrathoracic nodes together with patients with N2 abdominal nodes showed survivals of 14% at both 5 and 10 years. When tumors were staged as an esophageal carcinoma, classification of individual patients changed, as did the 5- and 10-year survivals. Five- and 10-year survivals were as follows: stage I (n = 8), 100% for both 5 and 10 years; stage II (n = 18), 68% for both 5 and 10 years; stage III (n = 27), 37% for both 5 and 10 years; and stage IV (n = 41), 10% for 5 years and 6% for 10 years. These data indicate that tumors of the esophagogastric junction tend to spread to both abdominal and thoracic nodes. However, reasonably good 5- and 10-year survivals can be obtained even in patients with nodal metastases in both areas. We suggest that N2 labeling be included for thoracic node metastases instead of the actual M+Ly label, because the N2 label better reflects the potential for curative surgery. Finally, staging tumors as gastric or esophageal carcinoma makes no significant difference in survival analysis, which raises the question whether these tumors behave more like esophageal carcinoma than gastric carcinoma.

Effect of various noise sources on the detective quantum efficiency of phosphor screens

We have examined the effect of screen-structure, optical-detector, and secondary-quantum noise sources on detective quantum efficiency, DQE(f). This was done by using experimental measurements of screen-structure and optical-detector noise in combination with a theoretical model which predicts x-ray quantum and secondary-quantum noise for different optical and physical properties of a phosphor screen. The reduction in DQE(f) from noise sources other than x-ray quantum noise depends on the noise power spectra (NPS) of these other sources relative to the x-ray quantum NPS. Even though x-ray quantum noise may be the dominant noise source at low spatial frequencies, it decreases relatively rapidly with increasing frequency so that other noise sources, which may be small at low frequencies, dominate. Our model predicts that DQE(f) can be increased, at spatial frequencies less than 4 mm-1, by changing the optical properties of the screen even though modulation transfer function MTF(f) may decrease. Furthermore, if screen and optical-detector noise decrease with increasing frequency and secondary-quantum noise sufficiently small, then DQE(f) will also be improved at frequencies greater than 4 mm-1.