Gastric cancer

Palliative gastrectomy and other factors affecting overall survival in stage IV gastric adenocarcinoma patients receiving chemotherapy: a retrospective analysis

OBJECTIVE

Most patients with gastric cancer present with locally advanced or metastatic disease and usually receive palliative therapy. We sought to identify factors influencing overall survival in patients with stage IV gastric cancer receiving palliative chemotherapy.

PATIENTS AND METHODS

The records of 311 patients with histological diagnosis of gastric adenocarcinoma were retrospectively reviewed and 17 clinicopathological and therapeutic parameters were evaluated for their influence on overall survival.

RESULTS

In multivariate analysis nine factors were found to independently influence survival: no previous palliative gastrectomy [Hazard ratio (HR, 12; CI 7.969-18.099)], single agent chemotherapy instead of combination chemotherapy (HR, 1.35; CI 1.068-1.721), histological grade III (HR, 1.39; 95% CI 1.098-1.782), the presence of hepatic (HR, 1.6; 95% CI 1.246-2.073) and abdominal metastasis (HR, 1.33; 95% CI 1.039-1.715), CA 72-4 > 7 U/L (HR, 1.39; 95% CI 1.026-1.887), LDH > 225 U/L (HR, 1.72; 95% CI 1.336-2.236], need for blood transfusions (HR, 1.58; 95% CI 1.213-2.082), and weight loss > 5% (HR, 1.96; 95% CI 1.352-2.853) at the time of initial diagnosis. Patients were stratified as low (0-2 factors), intermediate (3-6 factors) and high (7-9 factors) risk and the median survival was 76, 40 and 11 weeks, respectively.

CONCLUSION

Nine clinical and laboratory factors that adversely affect survival in patients with stage IV gastric cancer who receive chemotherapy were identified. Their concurrent presence seems to have an additive effect as patients with seven to nine factors have the worse prognosis. Palliative gastrectomy and combination chemotherapy appear to be associated with improved survival.

The association between GSTM1 polymorphism and gastric cancer risk: a meta-analysis

Relationship of gastric cancer with the GSTM1 polymorphism was reported with inconsistent results. The objective of this study was to quantitatively evaluate the association between GSTM1 polymorphism and gastric cancer susceptibility. Relevant studies were identified from PubMed and references of retrieved articles. A meta-analysis was performed, which included 38 studies with 6,605 gastric cancer cases and 11,311 controls. The combined result based on all studies showed there was a significant link between GSTM1 null genotype and gastric cancer (OR=1.20, 95%CI: 1.08-1.34). When stratifying for the race, the phenomenon was found that gastric cancer case had a significantly higher frequency of GSTM1 null genotype than control in Asians (OR=1.27, 95%CI: 1.10-1.47). However, there was not enough evidence to show there was a significant difference in GSTM1 null genotype distribution between gastric cancer case and control in Caucasians (OR=1.13, 95%CI: 0.96-1.32). This meta-analysis indicated that GSTM1 null genotype might be associated with increased gastric cancer risk in Asians. However, this meta-analysis did not provide an evidence of confirming association between GSTM1 polymorphism and gastric cancer in Caucasians.

Three aromatic amino acids in gastric juice as potential biomarkers for gastric malignancies

For screening early-stage gastric malignancies, the existing serum biomarkers have limited sensitivity and specificity. Gastric juice biomarkers are scarce and require further investigation. We divided this study on searching potential biomarkers into four parts: (1) detection of differential fluorescence spectrum and peaks in the gastric juice from patients using fluorescence spectroscopy and HPLC, (2) identification and validation of differential peaks using LC/MS and NMR, (3) quantification of potential biomarkers, and (4) establishment of diagnostic detection. The fluorescence intensity (FI), tyrosine, phenylalanine, tryptophan and total protein content were significantly higher in the gastric juice of patients with gastric malignancies (all P<0.01). With all P<0.001, the areas under the receiver operating characteristic curves of the biomarkers were tyrosine, 0.838; phenylalanine, 0.856; and tryptophan, 0.816. At a specificity of 79.4%, the sensitivity for gastric malignancy detection with phenylalanine was 87.9% only. Aromatic amino acids in gastric juices could be used as potential diagnostic biomarkers to screen gastric malignancies. It is a less-invasive and economical method compared to gastric biopsy.

MET expression and amplification in patients with localized gastric cancer

BACKGROUND

MET, the receptor for hepatocyte growth factor, has been proposed as a therapeutic target in gastric cancer. This study assessed the incidence of MET expression and gene amplification in tumors of Western patients with gastric cancer.

METHODS

Tumor specimens from patients enrolled on a preoperative chemotherapy study (NCI 5700) were examined for the presence of MET gene amplification by FISH, MET mRNA expression by quantitative PCR, MET overexpression by immunohistochemistry (IHC), and for evidence of MET pathway activation by phospho-MET (p-MET) IHC.

RESULTS

Although high levels of MET protein and mRNA were commonly encountered (in 63% and 50% of resected tumor specimens, respectively), none of these tumors had MET gene amplification by FISH, and only 6.6% had evidence of MET tyrosine kinase activity by p-MET IHC.

CONCLUSIONS

In this cohort of patients with localized gastric cancer, the presence of high MET protein and RNA expression does not correlate with MET gene amplification or pathway activation, as evidenced by the absence of amplification by FISH and negative p-MET IHC analysis.

IMPACT

This article shows a lack of MET amplification and pathway activation in a cohort of 38 patients with localized gastric cancer, suggesting that MET-driven gastric cancers are relatively rare in Western patients.

Survival of non-Western first generations immigrants with stomach cancer in North East Netherlands

Background:

Isolated groups, such as first generation non-Western immigrants, are at risk for suboptimal utilisation of the health care system resulting in a worse outcome.

Methods:

From 1989 to 2007, all patients with stomach cancer were selected from the Comprehensive Cancer Centre North-East cancer registry. Associations between country of birth and patient, tumour and treatment characteristics were determined using χ² analysis. Relative survival analysis was used to estimate relative excess risk of dying according to country of birth (non-Western vs Western).

Results:

After adjusting for confounding factors (patient, tumour and treatment related), the risk of dying was lower for first generation non-Western immigrants (relative excess risk 0.55, 95% confidence interval 0.43–0.70) compared with Western patients.

Conclusion:

Although the better survival of first generation non-Western immigrants with stomach cancer remains unexplained, it argues against accessibility problems within the Dutch health care system.

Treatment strategy for early gastric cancer

Gastric cancer ranks the second leading cause of cancer-specific mortality worldwide. With a poor prognosis, 5-year survival rate of gastric cancer is less than 20%-25% in the USA, Europe, and China [1]. However, early gastric cancer(EGC) offers an excellent (over 90%) chance of cure based on surgical resection [2]. As the increasing detection of EGC, more treatment options have been developed both curatively and minimally invasively to maintain a good quality of life(QOL). One of the advanced therapeutic techniques is endoscopic dissection. Improvements in surgical treatment include minimizing lymph node dissection, reconstruction methods, laparoscopy-assisted surgery, and sentinel node navigation surgery(SNNS) [3]. With technological advances, even Natural Orifice Transluminal Endoscopy Surgery (NOTES) and robotic surgery are expected to represent the next revolution [4]. However, there still remains much dispute among these treatments, which arouses further clinical trials to verify. Update of the treatments, controversial indications, prognosis and current strategies for EGC are discussed in this review.

Helicobacter pylori and gastric cancer

Gastric cancer remains a major cause of cancer death worldwide. The discovery of Helicobacter pylori Helicobacter pylori and its association with gastric cancer has opened up new insights into its pathogenesis. Gastric cancer pathogenesis is the result of a complex interplay between bacterial, host and environmental factors resulting in a step wise histological progression to neoplasia. H. pylori is a major factor in the early stages of cancer development and the mechanism of action of its virulence factors are being steadily unravelled. It is also now recognised that host genetic polymorphisms also play a complex role interacting synergistically with the bacterial virulence factors. The role of H. pylori in the causation of gastric cancer also raises the possibility of cancer prevention through screening and eradication, actions which may improve outcomes in high risk populations but which may not be cost-effective in areas of low risk. Ultimately, despite the vast improvements in knowledge, as yet there has not been a corresponding improvement in terms of gastric cancer survival rates.

The interaction between N-category and N-ratio as a new tool to improve lymph node metastasis staging in gastric cancer: results of a single cancer center in Brazil

BACKGROUND

Depth of tumor invasion (T-category) and the number of metastatic lymph nodes (N-category) are the most important prognostic factors in patients with gastric cancer. Recently, the ratio between metastatic and dissected lymph nodes (N-ratio) has been established as one. The aim of this study is to evaluate the impact of N-ratio and its interaction with N-category as a prognostic factor in gastric cancer.

METHODS

This was a retrospective study in which we reviewed clinical and pathological data of 165 patients who had undergone curative surgery at our institution through a 9-year period. The exclusion criteria included metastases, gastric stump tumors and gastrectomy with less than 15 lymph nodes dissected.

RESULTS

The median age of the patients was 63 years and most of them were male. Total gastrectomy was the most common procedure and 92.1% of the patients had a D2-lymphadenectomy. Their 5-year overall survival was 57.7%. T-category, N-category, extended gastrectomy, and N-ratio were prognostic factors in overall and disease-free survival in accordance with univariate analysis. In accordance with TNM staging, N1 patients who have had NR1 had 5-year survival in 75.5% whereas in the NR2 group only 33% of the cases had 5-year survival. In the multivariate analysis, the interaction between N-category and N-ratio was an independent prognostic factor.

CONCLUSION

Our findings confirmed the role of N-ratio as prognostic factor of survival in patients with gastric cancer surgically treated with at least 15 lymph nodes dissected. The relationship between N-category and N-ratio is a better predictor than lymph node metastasis staging.

Tumor expression of B7-H4 predicts poor survival of patients suffering from gastric cancer

To establish the prognostic value of B7-H4 expression by tumor cells in gastric cancer patients, we evaluated the association of B7-H4 expression with clinicopathologic factors and overall survival of gastric cancer patients. A retrospective cohort study including 156 gastric cancer patients was performed in the present report. Immunohistochemical assay was used to evaluate the expression of B7-H4 in the surgical specimens of gastric cancer tissues. Multi-univariate COX model was then used to evaluate the association of B7-H4 expression with the patients' survival and clinicopathological parameters. B7-H4 expression in the gastric cancer cells was observed in about 44.9% gastric cancer specimens. Univariate analysis demonstrated that there was no correlation between B7-H4 expression and sex, age, histological type, pathological grade or tumor size. In contrast, B7-H4 expression correlated positively with cancer invasiveness and lymph node metastasis. In addition, the median overall survival time of patients with lower B7-H4 expression was 13 months longer than that of patients with higher expression (chi(2) = 12.38, P < 0.0001), and the median disease-free survival time of patients with lower B7-H4 expression was significantly longer than that of patients with higher expression (33 vs. 16 months, chi(2) = 14.977, P < 0.0001). After adjustment for other confounding factors, the COX model analysis indicated that the death risk was significantly higher in patients with higher B7-H4 expression than those with lower expression (RR = 1.85, 95% CI = 1.15-2.96). The present study demonstrated that higher B7-H4 expression in cancer cells was associated with poor prognosis of gastric cancer patients. This is consistent with the idea that B7-H4 promotes cancer progression, likely via inhibition of anti-tumor immune responses.

HIF-1alpha is an unfavorable determinant of relapse in gastric cancer patients who underwent curative surgery followed by adjuvant 5-FU chemotherapy

Among several chemotherapeutic agents, 5-fluorouracil (5-FU) has been widely used as a key drug in adjuvant chemotherapy for gastric cancer. However, no reliable marker, which predicts the response to 5-FU in an adjuvant setting, has been identified. Hypoxia-induced drug resistance, via upregulation of HIF-1alpha, is a major obstacle in the development of effective cancer therapy. However, few clinical studies have so far assessed the relationship between the HIF-1alpha expression and the chemo-resistance of gastric cancer patients in an adjuvant setting. We established 2 HIF-1alpha knockdown gastric cancer cell lines in order to clarify the role of HIF-1alpha in chemo-resistance against 5-FU. Furthermore, expression of HIF-1alpha was immunohistochemically assessed in 91 resected specimens. Sixty-four of 91 patients received 5-FU adjuvant chemotherapy after surgery. HIF-1alpha expression was associated with the significantly shorter relapse-free survival and disease-specific survival in the 64 patients of adjuvant group (p = 0.026, 0.014, respectively), but not in the 27 of surgery group. Multivariate analysis showed that HIF-1alpha was an independent risk factor for relapse in 64 patients in the adjuvant group (p = 0.029). In conclusion, the current study confirmed, for the first time that HIF-1alpha expression is an independent risk factor for relapse in high-risk gastric cancer patients who underwent curative surgery followed by adjuvant 5-FU chemotherapy. A favorable effect of 5-FU might therefore be expected in patients that do not express HIF-1alpha, whereas, other types of chemotherapy or additional treatments, such as HIF-1alpha inhibitors, should be considered in patients that do express HIF-1alpha.

Is there a risk of cancer development after Campylobacter infection?

OBJECTIVE

All Campylobacter jejuni species produce a genotoxin, which induce DNA double strand breaks, could lead to an increased risk of cancer especially in the gastro-intestinal tract.

MATERIAL AND METHODS

All individuals in Stockholm County who tested positive with C. jejuni between 1989 and 2006 were included. The cohort was followed-up until December 31, 2007 for the occurrence of cancer, overall and site specific. Standard incidence ratios (SIR) with 95% confidence intervals (CI) were calculated by comparisons with the background population.

RESULTS

There were 16,276 individuals who tested positive for C. jejuni generating 124,387 person years. Excluding the first year of follow-up the overall risk for cancer did neither differ from that expected SIR = 0.95 (95% CI 0.82-1.09) nor after 10 years or more of follow-up; SIR = 0.91 (95% CI 0.71-1.16). There was no increased risk for cancer in the gastro-intestinal tract, but there were significantly increased risks for melanomas SIR = 1.84 (95% CI 1.27-2.57) and squamous cell skin cancer SIR = 1.52 (95% CI 1.01-2.19) while a significantly decreased risk of respiratory cancers among males SIR = 0.32 (95% CI 0.12-0.70) was observed.

CONCLUSIONS

Our results indicate no excess risks of malignancies following an infection by C. jejuni at least during the first decade. Furthermore, the finding of a decreased risk of respiratory cancers could be of interest, if the results are reproduced in future studies in other populations.

Gastroscopic and clinical diagnosis of early gastric cancer in elderly patients: an analysis of 124 cases

AIM: To investigate the clinicopathologic characteristics of early gastric cancer (EGC) in elderly patients.

METHODS: The clinical data for 124 elderly patients who were endoscopically diagnosed with EGC from May 1985 to December 2009 were retrospectively analyzed.

RESULTS: The mean age of these patients was 72.1 years. Elderly EGC patients usually had non-specific symptoms and physical signs. The tumors, most of which belonged to type IIb and IIc, were mainly located in the gastric sinus. Tumor diameter was usually less than 2 cm. Adenocarcinoma was the most common pathological type. Lymph node metastasis was noted in 3.2% (4/124) of patients.

CONCLUSION: There are usually no typical symptoms in elderly EGC patients. Mass screening by gastroscopy in combination with pathological examination is the most effective method to find EGC in elderly patients.

Role of capecitabine and irinotecan combination therapy in advanced or metastatic gastric cancer

Gastric cancer is one of the most common cancers and the second leading cause of cancer-related death. So far, the only curative treatment for gastric cancer is surgery. However, approximately half of all patients present with nonoperable tumors. Therefore, combination chemotherapy regimens are being accepted nowadays as first-line treatment for this disease. Despite the numerous efforts of randomized trials on advanced gastric cancer, no globally accepted regimen has yet been established. Historically, the most widely adopted protocols use 5-fluorouracil or platinum-based therapy with a response rate not exceeding 50% in combination therapy with a high rate of toxicity. Recently, many new drugs have emerged on the market and have been used in treating advanced or metastatic gastric cancer allowing the creation of new combination regimens with better clinical benefit. The combination of irinotecan plus capecitabine is one of these new combinations that seem to provide an acceptable response rate and good toxicity profile. In this article, we review the efficacy, tolerability, and feasibility of this combination for the treatment of advanced or metastatic gastric cancer and we summarize the clinical trials using this regimen.

Overexpression of endoglin (CD105) is associated with recurrence in radically resected gastric cancer

The aim of this study was to examine the expression of endoglin (CD105) in resected gastric cancer and to evaluate the relationship between microvessel density (MVD) and tumor recurrence after surgery. One hundred and thirty-two patients who had undergone curative surgery for primary gastric cancer were immunohistochemically stained for CD105, and MVD was assessed based on the number of CD105-positive vessels. MMP-7 expression was also investigated to determine the relationship with MVD. High MVD was significantly correlated with worse relapse-free survival in all cases and stage I-II cases by log-rank test (p=0.0005 and p=0.0154, respectively). Furthermore, in stage I-II cases, high MVD was the only independent predictor for relapse-free survival by multivariate analysis of the Cox proportional hazard model [p=0.028; hazard ratio (HR)=4.582; 95% confidence interval (CI) 1.184-17.737]. Regarding the specific patterns of recurrence, high MVD was independently related to locoregional recurrence [p=0.011; odds ratio (OR)=15.208; 95% CI 1.886-122.662] and hematogenous recurrence (p=0.002; OR=5.718; 95% CI 1.875-17.442) by multivariate logistic analysis. However, the expression of MMP-7 or CD105 combined with MVD was associated with relapse-free survival, although these prognostic impacts were not maintained in multivariate analysis. In conclusion, MVD recognized by CD105 may be useful as a predictor for the recurrence of resected gastric cancer and may have a specific association with the development of locoregional and hematogenous recurrence.

Relationship between XRCC3 T241M polymorphism and gastric cancer risk: a meta-analysis

The X-ray repair complementing defective repair in Chinese hamster cells 3 (XRCC3) gene is a member of the RAD51 gene family. It encodes an important protein that functions in the homologous recombination repair of DNA double-strand break. In this study, our aim was to explore the relationship between XRCC3 T241M polymorphism and gastric cancer risk. Performing both the overall meta-analysis and subgroup meta-analysis based on ethnicity, source of controls, and cancer location with a total of 6 eligible studies (1,154 cases and 1,487 controls in all), we detected no significant gastric cancer risk variation for all genetic models in the overall analysis and in the subgroup analysis based on cancer location. What is interesting is in the subgroup analysis based on ethnicity, where significantly decreased gastric cancer risk was observed for recessive model in Asians (OR=0.69, 95% CI=0.50-0.95), while significantly increased gastric cancer risk was detected for dominant model in Caucasians (OR=1.45, 95% CI=1.01-2.08). In summary, according to the results of our meta-analysis, the XRCC3 T241M polymorphism might influence gastric cancer risk oppositely in Asians and Caucasians.

Synergistic antitumor effect of S-1 and HER2-targeting agents in gastric cancer with HER2 amplification

Amplification of human epidermal growth factor receptor 2 (HER2) has been detected in 20% to 30% of gastric cancers and is associated with a poor outcome. Combination therapies with HER2-targeting agents and cytotoxic agents are considered a potential therapeutic option for gastric cancer with HER2 amplification. We have now investigated the effects of combination treatment with the oral fluoropyrimidine S-1 and the HER2-targeting agents lapatinib or trastuzumab in gastric cancer cells with or without HER2 amplification. We used 5-fluorouracil (5FU) instead of S-1 for in vitro experiments, given that tegafur, a component of S-1, is metabolized to 5FU in the liver. The combination of 5FU and HER2-targeting agents synergistically inhibited cell proliferation and exhibited an enhanced proapoptotic effect in gastric cancer cells with HER2 amplification, but not in those without it. Lapatinib or trastuzumab also induced downregulation of thymidylate synthase (TS) expression and activity only in cells with HER2 amplification. The combination of 5FU and TS depletion by RNA interference also exhibited an enhanced proapoptotic effect in cells with HER2 amplification. These observations thus suggest that lapatinib-induced or trastuzumab-induced downregulation of TS is responsible, at least in part, for the synergistic antitumor effect of combined treatment with 5FU and HER2-targeting agents. The antitumor effect of the combination of S-1 and HER2-targeting agents in vivo was also greater than that of either drug alone. Our preclinical findings thus indicate that the combination of S-1 and HER2-targeting agents is a promising treatment option for gastric cancer with HER2 amplification.

Identification of c-Src as a potential therapeutic target for gastric cancer and of MET activation as a cause of resistance to c-Src inhibition

Therapeutic strategies that target c-Src hold promise for a wide variety of cancers. We have now investigated both the effects of dasatinib, which inhibits the activity of c-Src and several other kinases, on cell growth as well as the mechanism of dasatinib resistance in human gastric cancer cell lines. Immunoblot analysis revealed the activation of c-Src at various levels in most gastric cancer cell lines examined. Dasatinib inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) and induced G(1) arrest, as revealed by flow cytometry, in a subset of responsive cell lines. In other responsive cell lines, dasatinib inhibited both ERK and AKT phosphorylation and induced apoptosis, as revealed by an increase in caspase-3 activity and cleavage of poly(ADP-ribose) polymerase. Depletion of c-Src by RNA interference also induced G(1) arrest or apoptosis in dasatinib-responsive cell lines, indicating that the antiproliferative effect of dasatinib is attributable to c-Src inhibition. Gastric cancer cell lines positive for the activation of MET were resistant to dasatinib. Dasatinib had no effect on ERK or AKT signaling, whereas the MET inhibitor PHA-665752 induced apoptosis in these cells. The subsets of gastric cancer cells defined by a response to c-Src or MET inhibitors were distinct and nonoverlapping. Our results suggest that c-Src is a promising target for the treatment of gastric cancer and that analysis of MET amplification might optimize patient selection for treatment with c-Src inhibitors.

[Tumors of the upper gastro-intestinal tract]

The appropriate extent of lymph node dissection in tumors of the upper gastro-intestinal tract continues to be debated. The basic tenet of surgical oncology that cancerous lymph nodes are indicators not governors of survival is under question and derives from the different theories of metastasis. Is the metastatic flow linear (indicators) or does it occur in parallel to tumorigenesis (governor)? If the latter theory is true there would be only a limited indication for lymphadenectomy (LA).Extended LA leads to an ameliorated staging of the N category. Following LA locoregional tumor control is significantly improved for esophageal and gastric cancer. In case of gastric cancer it is evident that there is a group of patients in which extended LA lead to improved long-term survival. This gain in prognosis affects patients in which lymph node metastasis is not or only slightly advanced. In locally advanced tumors there is no prognostic benefit. Patients who might benefit from the extended procedure cannot be assessed during preoperative staging. Therefore, the indications for the procedure should be liberally carried out by experienced hands and in experienced centers. According to randomized studies there is no indication for extended radical LA in pancreatic cancer.