Characteristics and clinical outcome of proximal-third gastric cancer

Neoadjuvant Chemotherapy Does Not Improve Survival in cT2N0M0 Gastric Adenocarcinoma Patients: A Multicenter Propensity Score Analysis

BACKGROUND

According to current international guidelines, stage cT2N0M0 gastric adenocarcinoma warrants preoperative chemotherapy followed by surgery. However, upfront surgery is often preferred in clinical practice, depending on patient clinical status and local treatment preferences.

OBJECTIVE

The aim of the present study was to assess the impact of neoadjuvant chemotherapy in overall survival (OS) and disease-free survival (DFS) of cT2N0M0 patients.

METHODS

A retrospective analysis was performed among 32 centers, including gastric adenocarcinoma patients operated between January 2007 and December 2017. Patients with cT2N0M0 stage were divided into upfront surgery (S) and neoadjuvant chemotherapy followed by surgery (CS) groups. Inverse probability of treatment weighting (IPTW) was used to compensate for baseline differences between the groups.

RESULTS

Among the 202 patients diagnosed with cT2N0M0 stage, 68 (33.7%) were in the CS group and 134 (66.3%) were in the S group. CS patients were younger (mean age 62.7 ± 12.8 vs. 69.8 ± 12.1 years for S patients; p < 0.001) and had a better health status (World Health Organization performance status = 0 in 60.3% of CS patients vs. 34.5% of S patients; p = 0.006). During follow-up, recurrence occurred in 27.2% and 19.6% of CS and S patients, respectively, after IPTW (p = 0.32). Five-year OS was similar between CS and S patients (78.9% vs. 68.3%; p = 0.42), as was 5-year DFS (70.4% vs. 68.5%; p = 0.96). Neoadjuvant chemotherapy was associated with neither OS nor DFS in multivariable analysis after IPTW.

CONCLUSIONS

Patients with cT2N0M0 gastric adenocarcinoma did not present a survival or recurrence benefit if treated with perioperative chemotherapy followed by surgery as opposed to surgery alone.

Abnormal arginine synthesis confers worse prognosis in patients with middle third gastric cancer

BACKGROUND

Gastric cancer at different locations has distinct prognoses and biological behaviors, but the specific mechanism is unclear.

METHODS

Non-targeted metabolomics was performed to examine the differential metabolite phenotypes that may be associated with the effects of tumor location on the prognosis of gastric cancer. And silencing of the rate-limiting enzyme to evaluate the effect of abnormal changes in metabolic pathway on the functional biological assays of gastric cancer cells HGC-27 and MKN28.

RESULTS

In a retrospective study of 94 gastric cancer patients, the average survival time of patients with gastric cancer in the middle third of the stomach was significantly lower than that of patients with gastric cancer in other locations (p < 0.05). The middle third location was also found to be an independent risk factor for poor prognosis (HR = 2.723, 95%CI 1.334-5.520), which was closely associated with larger tumors in this location. Non-targeted metabolomic analysis showed that the differential metabolites affected 16 signaling pathways including arginine synthesis, retrograde endocannabinoid signaling, arginine biosynthesis, and alanine and aspartate and glutamate metabolism between gastric cancer and normal tissue, as well as between tumors located in the middle third of the stomach and other locations. Argininosuccinate synthetase 1 (ASS1), the rate-limiting enzyme of the arginine biosynthesis pathway, catalyzes the production of argininosuccinic acid. Here, knockdown of ASS1 significantly inhibited the proliferation, colony formation, and migration/invasion of gastric cancer cells, and promoted apoptosis.

CONCLUSIONS

Our study suggests that abnormal arginine synthesis may lead to larger tumor size and worse prognosis in gastric cancer located in the middle third position of the stomach. These findings may provide the basis for the stratification and targeted treatment of gastric cancer in different locations.

Development and validation of a predictive model associated with lymph node metastasis of gastric signet ring carcinoma patients

The risk factors for lymph node metastasis (LNM) in patients with gastric signet ring cell carcinoma (GSRC) have not been well-defined. This study was designed to prognosticate LNM in patients with GSRC by constructing and verifying a nomogram. A total of 2789 patients with GSRC from the Surveillance, Epidemiology, and End Results (SEER) database and Yijishan Hospital of Wannan Medical College (YJS) were retrospectively reviewed. A predictive model was established using logistic regression based on the SEER cohort. The performance of the model was evaluated using the concordance index (C-index) and decision curve analysis (DCA). In addition, its robustness was validated using the YJS cohort. Four independent predictors of LNM were identified in the SEER cohort. Next, a nomogram was constructed by incorporating these predictors. The C-index were 0.800 (95% confidence interval [CI] = 0.781-0.819) and 0.837 (95% CI = 0.784-0.890) in the training and external validation cohorts, respectively. The outcomes of DCA supported good clinical benefits. The proposed model for evaluating the LNM in patients with GSRC can help to avoid the misdiagnosis risk of N-stage, assist to screen the population suitable for neoadjuvant therapy and help clinicians to optimize clinical decisions.

Artificial intelligence annotated clinical-pathologic risk model to predict outcomes of advanced gastric cancer

Background

Gastric cancer with synchronous distant metastases indicates a dismal prognosis. The success in survival improvement mainly relies on our ability to predict the potential benefit of a therapy. Our objective is to develop an artificial intelligence annotated clinical-pathologic risk model to predict its outcomes.

Methods

In participants (n=47553) with gastric cancer of the surveillance, epidemiology, and end results program, we selected patients with distant metastases at first diagnosis, complete clinical-pathologic data and follow-up information. Patients were randomly divided into the training and test cohort at 7:3 ratio. 93 patients with advanced gastric cancer from six other cancer centers were collected as the external validation cohort. Multivariable analysis was used to identify the prognosis-related clinical-pathologic features. Then a survival prediction model was established and validated. Importantly, we provided explanations to the prediction with artificial intelligence SHAP (Shapley additive explanations) method. We also provide novel insights into treatment options.

Results

Data from a total 2549 patients were included in model development and internal test (median age, 61 years [range, 53-69 years]; 1725 [67.7%] male). Data from an additional 93 patients were collected as the external validation cohort (median age, 59 years [range, 48-66 years]; 51 [54.8%] male). The clinical-pathologic model achieved a consistently high accuracy for predicting prognosis in the training (C-index: 0.705 [range, 0.690-0.720]), test (C-index: 0.737 [range, 0.717-0.757]), and external validation (C-index: 0.694 [range, 0.562-0.826]) cohorts. Shapley values indicated that undergoing surgery, chemotherapy, young, absence of lung metastases and well differentiated were the top 5 contributors to the high likelihood of survival. A combination of surgery and chemotherapy had the greatest benefit. However, aggressive treatment did not equate to a survival benefit. SHAP dependence plots demonstrated insightful nonlinear interactive associations among predictors in survival benefit prediction. For example, patients who were elderly, or poor differentiated, or presence of lung or bone metastases had a worse prognosis if they undergo surgery or chemotherapy, while patients with metastases to liver alone seemed to gain benefit from surgery and chemotherapy.

Conclusion

In this large multicenter cohort study, we developed an artificial intelligence annotated clinical-pathologic risk model to predict outcomes of advanced gastric cancer. It could be used to discuss treatment options.

Clinical Relevance of the Tumor Location-Modified Laurén Classification System for Gastric Cancer in a Western Population

Background

The Tumor Location-Modified Laurén Classification (MLC) system combines Laurén histologic subtype and anatomic tumor location. It divides gastric tumors into proximal non-diffuse (PND), distal non-diffuse (DND), and diffuse (D) types. The optimum classification of patients with Laurén mixed tumors in this system is not clear due to its grouping with both diffuse and non-diffuse types in previous studies. The clinical relevance of the MLC in a Western population has not been examined.

Methods

A cohort study investigated 404 patients who underwent gastrectomy for gastric adenocarcinoma between 2005 and 2020. The classification of Laurén mixed tumors was evaluated using receiver operating characteristic (ROC) curve analysis and comparison of clinicopathologic characteristics (chi-square). Survival analysis was performed using multivariable Cox regression.

Results

The ROC curve analysis demonstrated a slightly higher area under the curve value for predicting survival when Laurén mixed tumors were grouped with intestinal-type rather than diffuse-type tumors (0.58 vs 0.57). Survival, tumor recurrence, and resection margin positivity in mixed tumors also was more similar to intestinal type. Distal non-diffuse tumors had the best 5-year survival (DND 64.7 % vs PND 56.1 % vs diffuse 45.1 %; p = 0.006) and were least likely to have recurrence (DND 27.0 % vs PND 34.3 % vs diffuse 48.3 %; p = 0.001). Multivariable analysis demonstrated that MLC was an independent prognostic factor for survival (PND: hazard ratio [HR], 1.64; 95 % confidence interval [CI], 1.16–2.32 vs diffuse: HR, 2.20; 95 % CI, 1.56–3.09)

Conclusions

The MLC was an independent prognostic marker in this Western cohort of patients with gastric adenocarcinoma. The patients with PND and D tumors had worse survival than those with DND tumors.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-11252-y.

Comparison of the overall survival of proximal and distal gastric cancer after gastrectomy: a systematic review and meta-analysis

Background

The aim of this study was to investigate the overall survival (OS) between proximal gastric cancer (PG) and distal gastric cancer (DG) patients after gastrectomy.

Methods

Articles on the prognostic study of PG and DG patients after gastrectomy were collected from the PubMed, EMBASE, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang, and VIP databases from the date of establishment until December 2020. The data were statistically analyzed by Stata software (version 11.0, StataCorp).

Results

A total of 10 articles met the inclusion criteria. Meta-analysis showed that the 1-, 3- and 5-year OS rates of PG patients were significantly lower than those of DG patients (RR = 0.898, 95% CI: 0.825 to 0.977, P = 0.013; RR = 0.802, 95% CI: 0.708 to 0.909, P = 0.001; RR = 0.736, 95% CI: 0.642 to 0.844, P = 0.000). After subgroup analysis according to different countries, the combined RR values of were as follows: 1-year OS: eastern countries: RR = 0.966, 95% CI: 0.944 to 0.988, P = 0.003, western countries: RR = 0.687, 95% CI: 0.622 to 0.759, P = 0.000; 3-year OS: eastern countries: RR = 0.846, 95% CI: 0.771 to 0.929, P = 0.000, western countries: RR = 0.742, 95% CI: 0.399 to 1.382, P = 0.348; and 5-year OS: eastern countries: RR = 0.798, 95% CI: 0.716 to 0.889, P = 0.000, western countries: RR = 0.646, 95% CI: 0.414 to 1.008, P = 0.054.

Conclusion

In terms of 1-, 3-, and 5-year OS, PG patients had lower rates than DG patients and the eastern countries/western countries subgroup, but there were no significant differences in 3- and 5-year OS for the western countries. These results merit further clinical validation in future studies.

(Registration ID: UMIN000040393; Date of registration: 2020/05/13)

Comparison of clinicopathologic profiles and prognosis of gastric cancer in the upper, middle and lower third of the stomach: A retrospective cohort study

Gastric cancer (GC) is the fourth most common cancer in the world and the second most common cancer in China. The aim of this study was to investigate the clinicopathologic profiles and prognosis of GC in the upper third (UT), middle third (MT) and low third (LT) of the stomach.Five hundred and forty-two patients with GC resected between January 2010 and January 2014 were retrospectively studied and divided in 3 groups according to cancer location: upper third gastric cancer (UTGC) (n = 62); MTGC (n = 131) and LTGC (n = 349). Clinical and pathological parameters including gender, age, tumor size, macroscopic types, histological types, depth of invasion, lymph node metastasis, venous infiltration and lymph embolism were compared among groups. Overall survival (OS) was calculated based on the aforementioned parameters. Univariate and multivariate survival was analyzed and Cox regression was conducted for each location. The prognostic accuracy was determined using receiver operating characteristic curve analysis.Patients with UTGC was similar to those with MTGC and both were distinct from those with LTGC based on the tumor size, macroscopic types, depth of invasion and 5-year OS. Patients with MTGC were similar to those with LTGC and distinct from UTGC patients based on gender. 5-year OS were lower for patients with UTGC than those with LTGC (P = .001) and were comparable between MTGC and LTGC. No significant differences in 5-year OS were observed between UTGC and MTGC. Cox regression revealed that macroscopic types, depth of invasion and lymph node metastasis were the independent prognostic factors for GC patients regardless of locations. Receiver operating characteristic curve analysis revealed that macroscopic types, depth of invasion and lymph node metastasis were the significantly effective prognosis for the 5-year OS in GC patients regardless of locations.Our results showed that UTGC is distinct from LTGC whereas MTGC shares some characteristics from both UTGC and LTGC.

A prediction model for lymph node metastasis in early-stage gastric cancer: Toward tailored lymphadenectomy

BACKGROUND

The aim of this study was to develop a prediction model for the presence and location of lymph node metastasis (LNM) in early gastric cancer.

METHOD

We reviewed medical records of 4 929 patients who underwent radical gastrectomy for early gastric cancer. Variables of age, sex, lymphatic invasion, depth of invasion, location, gross type, differentiation, and tumor size were analyzed. Logistic regression analysis was used to determine independent predictors of LNM at each LN station.

RESULT

Overall incidence of LNM was 9.1% (448/4 929 patients). For the presence of LNM, risk factors of age, sex, lymphatic invasion, depth of invasion, anatomical part, gross ulceration, size, and tumor differentiation were significantly associated with LNM. The area under the curve (AUC) for predicting LNM after validation was 0.834 for the test set. For the location of LNM, age, sex, lymphatic invasion, depth of invasion, anatomical part, circumferential portion, gross type, differentiation, and tumor size were significantly associated with LNM. The AUC of each LN station was favorable with the test set.

CONCLUSION

Predicting the location of metastatic LNs appeared to be possible in patients with early gastric cancer.

Superiority of Tumor Location-Modified Lauren Classification System for Gastric Cancer: A Multi-Institutional Validation Analysis

Background

The tumor location-modified Lauren classification (mLC) has been proposed recently, but its clinical significance remains under debate. This study aimed to elucidate the clinical relevance of mLC and evaluate its superiority to the Lauren classification (LC) for gastric cancer patients with gastrectomy.

Methods

This study retrospectively evaluated 2764 consecutive gastric cancer patients from three comprehensive medical institutions. The patients were categorized into training, inner-validation, and independent validation sets. The relationships between mLC and other clinicopathologic factors were analyzed, and independent prognostic factors were identified. Survival prognostic discriminatory ability and predictive accuracy were compared between mLC and LC using the concordance index (C-index) and Akaike’s information criterion (AIC), and a nomogram based on mLC was constructed to compare its prognostic improvement with the tumor-node metastasis (TNM) staging system.

Results

A significant association between mLC and gender, age, histologic type, T stage, N stage, and M stage was found. The findings showed that mLC, not LC, is an independent prognostic factor, with a smaller AIC and a higher C-index than LC. The nomogram based on mLC showed a better predictive ability than TNM alone.

Conclusions

Compared with LC, mLC, which could be considered a more reliable prognostic factor, may improve the prognostic discriminatory ability and predictive accuracy for gastric cancer patients with gastrectomy.

Electronic supplementary material

The online version of this article (10.1245/s10434-018-6654-8) contains supplementary material, which is available to authorized users.

[R1 resection of esophageal carcinoma]

The microscopic identification of residual tumor tissue in the oral or aboral resection margins (R1 resection) of esophageal specimens following oncologic esophageal resection, increases the risk of tumor recurrence and disease-related morbidity. Esophageal resection with its associated risks is only meaningful, if an R0 situation can be safely achieved. The relevance of microscopic involvement of the circumferential resection margin (CRM) in esophageal carcinoma in its different definitions by the British and the American Societies of Pathology has up to now never been investigated in a prospective study. According to the German S3 guideline, radiochemotherapy should be performed in a postoperatively proven R1 situation, which cannot be converted by a curative extended re-resection into an R0 situation or in unfavorable conditions for an extended re-resection, independent of neoadjuvant therapy. In the case of an R1 situation in the region of the CRM, an extended re-resection is not simply possible on account of the anatomical conditions with corresponding limitations by the aorta and the spinal column, in contrast to extensions of the re-resection orally or aborally.

Insights into next developments in advanced gastric cancer

PURPOSE OF REVIEW

The purpose of the review is to delineate novel approaches for biology-based treatment in advanced gastric cancer. We reviewed the latest translational and clinical research articles and congress presentations.

RECENT FINDINGS

A new molecular classification of gastric cancer based on histology, genetic and proteomic alterations has evolved. It provides a roadmap for development of new drugs and combinations and for patient stratification. Anti-HER2 treatment, which is an effective strategy in metastatic gastric cancer, is now also being studied in the perioperative setting. However, resistance mechanisms in advanced disease are poorly understood and optimal patient selection remains challenging. Targeting angiogenesis is an emerging concept in the management of advanced gastric cancer, and ramucirumab has prolonged survival in the second line either as a monotherapy or in combination with paclitaxel. Biomarkers for selecting patients who benefit from ramucirumab are still lacking. Immune checkpoint blockade and inhibition of cancer stemness targets are other emerging directions for the medical treatment of gastric cancer. Large-scale international studies are ongoing.

SUMMARY

Promising biology-based treatment strategies are evolving. But tumor heterogeneity which is an inherent feature of gastric cancer challenges the development of molecularly targeted and personalized treatment strategies.

Clinical Outcomes of Endoscopic Submucosal Dissection for Adenocarcinoma of the Esophagogastric Junction

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) for adenocarcinoma in the esophagogastric junction (EGJ) is a technically difficult procedure. We analyzed the long-term clinical outcomes of ESD for adenocarcinoma in the EGJ to determine the feasibility of this treatment approach.

METHODS

Subjects who underwent ESD for Siewert type II adenocarcinoma between December 2004 and December 2011 were eligible for this study. Clinical features and treatment outcomes were retrospectively reviewed using medical records.

RESULTS

A total of 88 subjects underwent ESD at our institute. The median patient age was 66 years (interquartile range [IQR] 59-71 years), and the male-to-female ratio was 10.0:1. The median tumor diameter was 20 mm (IQR 14-25 mm), and the median procedure time was 40 min (IQR 30-60 min). Adverse events occurred in nine patients (10.2 %), namely bleeding (n = 6) and suspicious microperforation (n = 3). En bloc, complete, and curative resection rates were 88.6 % (78/88), 83.0 % (73/88), and 60.2 % (53/88), respectively. In multivariate analysis, undifferentiated histology (P = 0.009) and elevated lesions (P = 0.011) were factors associated with noncurative resection. During a median follow-up period of 68.5 months, local tumor recurrence was detected in two patients (2.4 %), and the 5-year overall and disease-specific survival rates were 96.6 and 100.0 %, respectively.

CONCLUSIONS

ESD for the treatment of EGJ cancer may be an effective and safe treatment strategy based on favorable long-term outcomes.

Clinical impact of tumour biology in the management of gastroesophageal cancer

The characterization of oesophageal and gastric cancer into subtypes based on genotype has evolved in the past decade. Insights into the molecular landscapes of gastroesophageal cancer provide a roadmap to assist the development of new drugs and their use in combinations, for patient stratification, and for trials of targeted therapies. Trastuzumab is the only approved treatment for gastroesophageal cancers that overexpress HER2. Acquired resistance usually limits the duration of response to this treatment, although a number of new agents directed against HER2 have the potential to overcome or prolong the time until resistance occurs. Beyond that, anti-VEGFR2 therapy with ramucirumab was the first biological treatment strategy to produce a survival benefit in an unselected population of patients with chemotherapy-refractory gastroesophageal cancer. Large initiatives are starting to address the role of biomarker-driven targeted therapy in the metastatic and in the perioperative setting for patients with this disease. Immunotherapy also holds promise, and our understanding of subsets of gastroesophageal cancer based on patterns of immune response continues to evolve. Efforts are underway to identify more relevant genomic subsets through genomic screening, functional studies, and molecular characterization. Herein, we provide an overview of the key developments in the treatment of gastroesophageal cancer, and discuss potential strategies to further optimize therapy by targeting disease subtypes.

Clinical Relevance of the Tumor Location-Modified Lauren Classification System of Gastric Cancer

Purpose

The Lauren classification system is a very commonly used pathological classification system of gastric adenocarcinoma. A recent study proposed that the Lauren classification should be modified to include the anatomical location of the tumor. The resulting three types were found to differ significantly in terms of genomic expression profiles. This retrospective cohort study aimed to evaluate the clinical significance of the modified Lauren classification (MLC).

Materials and Methods

A total of 677 consecutive patients who underwent curative gastrectomy from January 2005 to December 2007 for histologically confirmed gastric cancer were included. The patients were divided according to the MLC into proximal non-diffuse (PND), diffuse (D), and distal non-diffuse (DND) type. The groups were compared in terms of clinical features and overall survival. Multivariate analysis served to assess the association between MLC and prognosis.

Results

Of the 677 patients, 48, 358, and 271 had PND, D, and DND, respectively. Their 5-year overall survival rates were 77.1%, 77.7%, and 90.4%. Compared to D and PND, DND was associated with significantly better overall survival (both P<0.01). Multivariate analysis showed that age, differentiation, lympho-vascular invasion, T and N stage, but not MLC, were independent prognostic factors for overall survival. Multivariate analysis of early gastric cancer patients showed that MLC was an independent prognostic factor for overall survival (odds ratio, 5.946; 95% confidence intervals, 1.524~23.197; P=0.010).

Conclusions

MLC is prognostic for survival in patients with gastric adenocarcinoma, in early gastric cancer. DND was associated with an improved prognosis compared to PND or D.

Function and diagnostic value of Anosmin-1 in gastric cancer progression

Gastric cancer (GC) is a major global health problem that urgently requires novel molecular biomarkers for patient stratification as well as therapeutic targets. Anosmin-1 (ANOS1) gene encodes a cell adhesion molecule that plays diverse roles in multiple malignancies. We performed global expression profiling of GC cell lines and small interfering RNA (siRNA) experiments to determine the effect of ANOS1 expression on phenotype. We evaluated the association of ANOS1 mRNA and protein levels in patients' tissue and sera with clinicopathological factors of GC subtypes. Differential expression of ANOS1 mRNA by GC cell lines correlated positively to levels of ITGAV, FOXC2 and NODAL mRNAs and inversely with those of TFPI2. Inhibiting ANOS1 expression decreased the proliferation, invasion and migration of GC cells. The mean level of ANOS1 mRNA was significantly higher in 237 GC tissues compared with the corresponding noncancerous adjacent tissues. Elevated ANOS1 levels associated significantly with the phenotypes of GC, shorter disease-free and overall survival. ANOS1 expression was a more significant prognostic marker for diffuse and distal nondiffuse GC. ANOS1 concentrations in sera increased sequentially in sera of healthy subjects, localized GC and disseminated GCs. Prognosis was worse for patients with preoperative serum ANOS1 ≥ 600 pg/ml compared with those with <600 pg/ml. ANOS1 may represent a biomarker for GC phenotypes and as a target for therapy.

Diversity of clinical implication of B-cell translocation gene 1 expression by histopathologic and anatomic subtypes of gastric cancer

BACKGROUND

Genetic signatures may differ by histopathologic and anatomic subtypes of gastric cancer (GC). B-cell translocation gene 1 (BTG1) was identified as one of genes downregulated in GC tissues from our microarray data.

AIMS

To evaluate the clinical implications of BTG1 expression in GC and the genetic diversity among GC subtypes.

METHODS

BTG1 mRNA expression was analyzed in GC cell lines and 233 pairs of surgical specimens. The mutational and methylation status of BTG1 in GC cell lines was analyzed, and immunohistochemistry was conducted to determine the distribution of BTG1. The pattern and prognostic significance of BTG1 expression were correlated with the three proposed GC subtypes.

RESULTS

BTG1 mRNA was downregulated in 82 % of GC cell lines and in 88 % of clinical GC tissues. Promoter hypermethylation events or sequence mutations were not detected in GC cell lines. The pattern of BTG1 expression as observed by immunohistochemistry was consistent with that of its mRNA. Downregulation of BTG1 mRNA in GCs was significantly associated with shorter disease-specific and recurrence-free survival. Multivariate analysis of disease-specific survival identified downregulation of BTG1 transcription as an independent prognostic factor. BTG1 mRNA expression was more strongly suppressed in proximal nondiffuse and diffuse GC compared with distal nondiffuse GC, and subgroup analysis revealed that BTG1 downregulation led to adverse prognosis, specifically in patients with proximal nondiffuse and diffuse GC.

CONCLUSIONS

Altered expression of BTG1 is a potential biomarker for carcinogenesis and progression of GC, particularly for proximal nondiffuse and diffuse GC.

Dihydropyrimidinase-like 3 facilitates malignant behavior of gastric cancer

BACKGROUND

Gastric cancer (GC) remains to have a poor prognosis via diverse process of cancer progression. Dihydropyrimidinase-like 3 (DPYSL3) is a cell adhesion molecule that has been reported to be involved in the metastatic process of tumor cells. The aim of this study was to identify a novel clinically-relevant biomarker of GC.

METHODS

Expression analysis of DPYSL3 mRNA and protein levels was conducted using GC cell lines and 238 pairs of surgically resected gastric tissues. Correlations between expression status of DPYSL3 and clinicopathological parameters were investigated.

RESULTS

DPYSL3 mRNA expression levels positively correlated with those of potentially interacting genes (VEGF, FAK and EZR) in GC cell lines. GC tissues from tumors with distant metastases (stage IV cancer) showed elevated expression levels of DPYSL3 mRNA. The DPYSL3 staining intensity in immunochemical staining was consistent with the mRNA expression patterns in GC tissues. High DPYSL3 mRNA expression in GCs was significantly associated with more malignant phenotypes and was an independent prognostic factor. Moreover, patients with high DPYSL3 mRNA expression had a significantly shorter recurrence free survival after curative resection. In subgroup analysis based on tumor histology, similar tendency was observed between patients with differentiated and undifferentiated GCs.

CONCLUSIONS

Expression status of DPYSL3 in GC tissues may represent a promising biomarker for the malignant behavior of GC.

Dihydropyrimidinase-like 3 facilitates malignant behavior of gastric cancer

Background

Gastric cancer (GC) remains to have a poor prognosis via diverse process of cancer progression. Dihydropyrimidinase-like 3 (DPYSL3) is a cell adhesion molecule that has been reported to be involved in the metastatic process of tumor cells. The aim of this study was to identify a novel clinically-relevant biomarker of GC.

Methods

Expression analysis of DPYSL3 mRNA and protein levels was conducted using GC cell lines and 238 pairs of surgically resected gastric tissues. Correlations between expression status of DPYSL3 and clinicopathological parameters were investigated.

Results

DPYSL3 mRNA expression levels positively correlated with those of potentially interacting genes (VEGF, FAK and EZR) in GC cell lines. GC tissues from tumors with distant metastases (stage IV cancer) showed elevated expression levels of DPYSL3 mRNA. The DPYSL3 staining intensity in immunochemical staining was consistent with the mRNA expression patterns in GC tissues. High DPYSL3 mRNA expression in GCs was significantly associated with more malignant phenotypes and was an independent prognostic factor. Moreover, patients with high DPYSL3 mRNA expression had a significantly shorter recurrence free survival after curative resection. In subgroup analysis based on tumor histology, similar tendency was observed between patients with differentiated and undifferentiated GCs.

Conclusions

Expression status of DPYSL3 in GC tissues may represent a promising biomarker for the malignant behavior of GC.

Neoadjuvant Therapy of Gastric Cancer: A Decisive Step Forward

BACKGROUND

Although its incidence has been steadily decreasing in Western countries, gastric cancer remains a leading cause of cancer deaths worldwide. The detection rate of early-stage cancers is improving; nevertheless, the majority of cases is still diagnosed at later stages with a poor prognosis. Furthermore, the results that can be achieved with surgery have reached a plateau of effectiveness.

SUMMARY

Neoadjuvant chemotherapy was successfully introduced first in patients with non-curatively resectable disease. In the last decade, neoadjuvant chemotherapy has also been established in potentially curatively resectable cases and has become the state-of-the-art treatment. Esophagogastric junction (EGJ) tumors are not optimally treated with chemotherapy alone, and combined radiochemotherapy (RCT) seems to yield superior outcomes.

KEY MESSAGE

The use of neoadjuvant therapy has been successfully established in patients with curatively resectable disease. Neoadjuvant chemotherapy is now a cornerstone in the treatment of gastric cancer and cancer of the EGJ, although further work is needed in order to define the optimal combination regimen.

PRACTICAL IMPLICATIONS

Neoadjuvant chemotherapy is currently the gold standard for the treatment of gastric cancer and cancer of the EGJ. Several independent studies have shown the benefits of using combination regimens that included cisplatin and 5-fluorouracil, though recently the use of the EOX (epirubicin, oxaliplatin and capecitabine) regimen has been widely accepted in this setting. Tumors of the EGJ benefit from neoadjuvant treatment with combined RCT. It should be noted that the optimal neoadjuvant regimen in EGJ tumors has not yet been defined, and the survival advantage of neoadjuvant RCT over neoadjuvant chemotherapy remains to be established in this patient population.

Genetic polymorphisms in the microRNA binding-sites of the thymidylate synthase gene predict risk and survival in gastric cancer

Thymidylate synthase (TYMS) plays a crucial role in folate metabolism as well as DNA synthesis and repair. We hypothesized that functional polymorphisms in the 3' UTR of TYMS are associated with gastric cancer risk and survival. In the present study, we tested our hypothesis by genotyping three potentially functional (at miRNA binding sites) TYMS SNPs (rs16430 6bp del/ins, rs2790 A>G and rs1059394 C>T) in 379 gastric cancer patients and 431 cancer-free controls. Compared with the rs16430 6bp/6bp + 6bp/0bp genotypes, the 0bp/0bp genotype was associated with significantly increased gastric cancer risk (adjusted OR = 1.72, 95% CI = 1.15-2.58). Similarly, rs2790 GG and rs1059394 TT genotypes were also associated with significantly increased risk (adjusted OR = 2.52, 95% CI = 1.25-5.10 and adjusted OR = 1.57, 95% CI = 1.04-2.35, respectively), compared with AA + AG and CC + CT genotypes, respectively. In the haplotype analysis, the T-G-0bp haplotype was associated with significantly increased gastric cancer risk, compared with the C-A-6bp haplotype (adjusted OR = 1.34, 95% CI = 1.05-1.72). Survival analysis revealed that rs16430 0bp/0bp and rs1059394 TT genotypes were also associated with poor survival in gastric cancer patients who received chemotherapy treatment (adjusted HR = 1.61, 95% CI = 1.05-2.48 and adjusted HR = 1.59, 95% CI = 1.02-2.48, respectively). These results suggest that these three variants in the miRNA binding sites of TYMS may be associated with cancer risk and survival of gastric cancer patients. Larger population studies are warranted to verify these findings.

Polymorphisms at the microRNA binding-site of the stem cell marker gene CD133 modify susceptibility to and survival of gastric cancer

CD133 is one of the most common stem cell markers, and functional single nucleotide polymorphisms (SNPs) of CD133 may modulate its gene functions and thus cancer risk and patient survival. We hypothesized that potentially functional CD133 SNPs are associated with gastric cancer (GC) risk and survival. To test this hypothesis, we conducted a case-control study of 371 GC patients and 313 cancer-free controls frequency-matched by age, sex, and ethnicity. We genotyped four selected, potentially functional CD133 SNPs (rs2240688A>C, rs7686732C>G, rs10022537T>A, and rs3130C>T) and used logistic regression analysis for associations of these SNPs with GC risk and Cox hazards regression analysis for survival. We found that compared with the miRNA binding site rs2240688 AA genotype, AC + CC genotypes were associated with significantly increased GC risk (adjusted OR = 1.52, 95% CI = 1.09-2.13); for another miRNA binding site rs3130C>T SNP, the TT genotype was associated with significantly reduced GC risk (adjusted OR = 0.68, 95% CI = 0.48-0.97), compared with CC + CT genotypes. In all patients, the risk rs3130 TT variant genotype was significantly associated with overall survival (OS) (adjusted P(trend) = 0.016 and 0.007 under additive and recessive models, respectively). These findings suggest that these two CD133 miRNA binding site variants, rs2240688 and rs3130, may be potential biomarkers for genetic susceptibility to GC and possible predictors for survival in GC patients but require further validation by larger studies.

Clinical evidence for three distinct gastric cancer subtypes: time for a new approach

BACKGROUND

Recently, a new classification for gastric cancer (GC) has been proposed, based on Lauren's histology and on anatomic tumour location, identifying three subtypes of disease: type 1 (proximal non diffuse GC), type 2 (diffuse GC) and type 3 (distal non diffuse GC). Aim of our analysis was to compare clinical outcome according to different GC subtypes (1,2,3) in metastatic GC patients receiving first-line chemotherapy.

PATIENTS AND METHODS

Advanced GC pts treated with a first-line combination chemotherapy were included in our analysis. Pts were divided in three subgroups (type 1, type 2 and type 3) as previously defined.

RESULTS

A total of 248 advanced GC pts were included: 45.2% belonged to type 2, 43.6% to type 3 and 11.2% to type 1. Patients received a fluoropyrimidine-based chemotherapy doublet or three drugs regimens including a platinum derivate and a fluoropyrimidine with the addition of an anthracycline, a taxane or mytomicin C. RR was higher in type 1 pts (RR = 46.1%) and type 3 (34,3%) compared to type 2 (20,4%), (p = 0.015). Type 2 presented a shorter PFS, median PFS = 4.2 months, compared to type 1, mPFS = 7.2 months, and type 3, mPFS = 5.9 months (p = 0.011) and also a shorter OS (p = 0.022).

CONCLUSIONS

Our analysis suggests that GC subtypes may be important predictors of benefit from chemotherapy in advanced GC patients. Future clinical trials should take in account these differences for a better stratification of patients.

Gastric stump cancer: more than just another proximal gastric cancer and demanding a more suitable TNM staging system

Background. Considerable controversy persists about the biological behavior of gastric stump cancer (GSC). The aim of this study is to clarify if this cancer is just another proximal gastric cancer or if it emerges as a distinctive clinicopathologic entity. Methods. This review of a prospectively collected gastric cancer database identified 73 patients with GSC in a single institution between January 1980 and June 2012 and compared them with 328 patients with proximal gastric cancer (PGC) and 291 patients with esophagogastric junction cancer (EGJC). Results. Patients with GSC were predominantly males. Eighty-three percent of GSC penetrated the subserosal or the serosal layers. The median number of lymph nodes retrieved in GSC patients was significantly lower than in PGC patients or in EGJC patients. Cumulative survival curves were not different between GSC, PGC, or EGJC patients. Unlike that observed in PGC and in EGJC, no significant differences in cumulative survival according to the TNM staging system were observed in GSC cases. Conclusions. The outcome of patients with GSC displayed significant differences when compared to those with other proximal gastric cancers concerning the lack of survival association with the TNM staging system. Therefore a more suitable staging system should be designed for these unique cancers.

Should adenocarcinoma of the esophagogastric junction be classified as esophageal cancer? A comparative analysis according to the seventh AJCC TNM classification

OBJECTIVE

The aim of this study was to evaluate the adequacy of esophageal classification for adenocarcinoma of the esophagogastric junction (AEJ) of the seventh American Joint Committee on Cancer (AJCC) TNM classification.

BACKGROUND

The seventh AJCC TNM classification proposed the new classification for AEJ as a part of esophageal cancer depending on the esophagogastric junction (EGJ) involvement. However, there are still many controversies over the classification system for AEJ.

METHODS

A review of pathologic reports and photographic findings at Seoul National University Hospital from 2003 to 2009 identified 4524 patients with single, primary adenocarcinoma of the EGJ (n = 497) and other regions of the stomach (GC, n = 4027) who underwent an operation with curative intent. We analyzed the clinicopathologic features and postoperative prognosis of AEJ using the Siewert classification and the seventh AJCC TNM classification.

RESULTS

There was no Siewert type I (AEJ I) in this study. The prognosis of AEJ was similar to that of GC. There was no difference in clinicopathologic features between AEJ II and AEJ III. Even though AEJ extending into the EGJ (AEJe) showed more advanced pathologic features than AEJ not extending into the EGJ (AEJg), the prognosis of AEJe and AEJg was not significantly different when stratified by T stage. Compared with the classification of gastric cancer applied for AEJ, esophageal classification for AEJ from the seventh AJCC TNM classification showed a loss of distinctiveness at each TNM stage.

CONCLUSIONS

To evaluate the postoperative prognosis of AEJ within the stomach, AEJ II and AEJ III should be considered a part of gastric cancer irrespective of EGJ involvement.

Molecular classification of gastric cancer: a new paradigm

PURPOSE

Gastric cancer may be subdivided into 3 distinct subtypes--proximal, diffuse, and distal gastric cancer--based on histopathologic and anatomic criteria. Each subtype is associated with unique epidemiology. Our aim is to test the hypothesis that these distinct gastric cancer subtypes may also be distinguished by gene expression analysis.

EXPERIMENTAL DESIGN

Patients with localized gastric adenocarcinoma being screened for a phase II preoperative clinical trial (National Cancer Institute, NCI #5917) underwent endoscopic biopsy for fresh tumor procurement. Four to 6 targeted biopsies of the primary tumor were obtained. Macrodissection was carried out to ensure more than 80% carcinoma in the sample. HG-U133A GeneChip (Affymetrix) was used for cDNA expression analysis, and all arrays were processed and analyzed using the Bioconductor R-package.

RESULTS

Between November 2003 and January 2006, 57 patients were screened to identify 36 patients with localized gastric cancer who had adequate RNA for expression analysis. Using supervised analysis, we built a classifier to distinguish the 3 gastric cancer subtypes, successfully classifying each into tightly grouped clusters. Leave-one-out cross-validation error was 0.14, suggesting that more than 85% of samples were classified correctly. Gene set analysis with the false discovery rate set at 0.25 identified several pathways that were differentially regulated when comparing each gastric cancer subtype to adjacent normal stomach.

CONCLUSIONS

Subtypes of gastric cancer that have epidemiologic and histologic distinctions are also distinguished by gene expression data. These preliminary data suggest a new classification of gastric cancer with implications for improving our understanding of disease biology and identification of unique molecular drivers for each gastric cancer subtype.

Changes in clinicopathological features and survival after gastrectomy for gastric cancer over a 20-year period

BACKGROUND

The pattern of gastric cancer in the Western world is changing, with an increased proportion of tumours in the upper stomach. The aim of this study was to investigate changes in clinicopathological features and survival of patients with resected gastric cancer at a single institution, in an area of high incidence in the Far East.

METHODS

Clinical features and pathological findings were compared in patients with gastric cancer who underwent gastrectomy at Seoul National University Hospital during four consecutive periods (1986-1990, 1991-1995, 1996-2000 and 2001-2006).

RESULTS

There were 12 026 patients. The mean age increased from 53·4 years in the first period to 57·4 years in the last (P < 0·001). The proportion of patients aged 70 years or older also increased, reaching 16·1 per cent in the final period. Upper-third cancer increased from 5·3 per cent in the first period to 14·0 per cent in the fourth (P < 0·001). Early gastric cancer (pathological T1) increased continuously over the four time intervals, from 24·8 to 48·9 per cent (P < 0·001). The overall 5-year survival rate increased from 64·0 per cent in the first period to 73·2 per cent at the end (P < 0·001), and this survival improvement was apparent in patients aged 40 years or more.

CONCLUSION

The mean age of patients with gastric cancer has increased during the past 20 years. The proportion of early gastric cancer and overall survival have gradually increased, especially in patients aged over 40 years.

Gastric cancer: Where is the place for the surgeon, the oncologist and the endoscopist today?

Gastric cancer remains a major health issue and a leading cause of death worldwide. While the incidence is decreasing in western countries, there has been a shift to more proximal cancers of the diffuse type, which are usually more aggressive and associated with a worse prognosis. Radical surgery still offers the only chance of long term survival, but surgery has reached a plateau of effectiveness and more aggressive approaches like “ultraradical” lymphadenectomy have not improved prognosis. There are three options to improve the situation: Earlier detection, neoadjuvant chemotherapy and adjuvant therapy. Whilst systematic gastroscopic screening makes sense in countries with a high incidence of gastric cancer, in other regions targeted investigation of risk groups including first-degree relatives of cancer patients, patients with a chronic corpus-dominant gastritis or with defined genetic abnormalities may help to detect cancer at an earlier stage. Neoadjuvant chemotherapy has meanwhile proved to significantly improve the prognosis not only in patients with a locally advanced cancer who cannot be resected for cure but but also in those who are potentially amenable to curative resection. In the largest randomised study so far reported, perioperative chemotherapy raised overall survival after 5 years from 23% to 36%. The role of adjuvant chemotherapy has been discussed for over 30 years. Meta-analyses demonstrate a small but significant effect which, however, seems to be restricted to Asian patients. In a large US-study, adjuvant radiochemotherapy appeared to significantly improve outcomes. However, less than 50% of the study patients underwent a systematic lymphadenectomy and so the results of the therapy group were not better to those of “only resected” patients in two large European studies. Thus, the indication of adjuvant (radio-)chemotherapy in gastric cancer currently remains uncertain. Endoscopists have found a therapeutic role through endoscopic resection of early cancers, introduced mainly by Japanese authors. With the development of high resolution endoscopy, endosonography and adequate equipment, the endoscopic curative resection of T1a-tumors (restricted to the mucosal layer) has been established.

Clinicopathological Features of Upper Third Gastric Cancer during a 21-Year Period (Single Center Analysis)

Purpose

The aim of this study was to determine proportions of upper third gastric cancer (UTG) among all gastric cancers and analyze clinicopathological features of the disease.

Materials and Methods

The medical records of 12,300 patients who underwent gastric surgery between 1986 and 2006 at Seoul National University Hospital (SNUH) were retrospectively reviewed. Clinicopathological features of 1,260 patients with UTG and 9,929 patients with middle or lower third gastric cancer (MLG) were compared, and annual proportions of UTG were evaluated.

Results

The proportion of patients with UTG rapidly increased from 2.6% in 1986 to 12.5% in 1992. However, linear regression analysis showed that the rate of increase was reduced (0.21%/year) after 1992 (12.5% to 14.2% from 1992 to 2006). Compared with the MLG group, the UTG group had a lower proportion of (22.3% vs. 39.7%, P<0.001) and a greater proportion of stage III/IV disease (39.4% vs. 31.7%, P<0.001). The UTG group also had larger tumors than the MLG group in stages I/II and III (3.5 cm/5.3 cm/6.5 cm vs. 3.2 cm/5.0 cm/5.8 cm, P=0.020/0.028 /<0.001), a higher proportion of undifferentiated cancer (63.1% vs. 53.7%, P<0.001), and less intestinal Lauren's type (38.8% vs. 47.4%, P<0.001). The 5-year survival rate of the UTG group was significantly lower than that of the MLG group in stages I/II and III (85.6%/63.1%/34.2% vs. 91.6%/ 69.2%/44.7%, P<0.001/0.028/0.006).

Conclusions

The proportion of UTGs has increased over the last two decades at SNUH, but the rate of increase has been greatly reduced since 1992. The UTG group showed a poorer prognosis compared with the MLG group in stages I/II and III.

Phase II study of modified docetaxel, cisplatin, and fluorouracil with bevacizumab in patients with metastatic gastroesophageal adenocarcinoma

PURPOSE

To evaluate the safety and efficacy of a modified administration schedule of docetaxel, cisplatin, and fluorouracil (mDCF) with bevacizumab in patients with advanced gastroesophageal malignancies.

PATIENTS AND METHODS

Previously untreated patients with metastatic gastroesophageal adenocarcinoma received bevacizumab 10 mg/kg, docetaxel 40 mg/m², fluorouracil 400 mg/m², leucovorin 400 mg/m² on day 1, fluorouracil 1,000 mg/m²/d × 2 days intravenous continuous infusion beginning on day 1, and cisplatin 40 mg/m² on day 3. The primary objective was to improve 6-month progression-free survival (PFS) from 43% (historical DCF control) to 63% with the addition of bevacizumab. The target accrual was 44 patients to have 10% type I and II error rates.

RESULTS

In total, 44 eligible patients with cancer were enrolled from October 2006 to October 2008: 22 gastric, 20 gastroesophageal junction (GEJ), and two esophagus. In 39 patients with measurable disease, the confirmed response rate was 67% (95% CI, 50% to 81%). Six-month PFS was 79% (95% CI, 63% to 88%), and median PFS was 12 months (95% CI, 8.8 to 18.2 months). With 26-month follow-up, median overall survival (OS) was 16.8 months (95% CI, 12.1 to 26.1 months), and 2-year survival was 37%. Treatment-related grade 3 to 4 toxicity was as follows: neutropenia without fever (50%), fatigue (25%), venous thromboembolism (39%), and nausea, vomiting, mucositis, neuropathy, and febrile neutropenia less than 10% each. In subset analysis, diffuse gastric cancer had significantly worse PFS and OS, and the response rate in proximal/GEJ tumors was 85% (95% CI, 62% to 97%).

CONCLUSION

mDCF with bevacizumab appears tolerable and has notable patient outcomes in patients with advanced gastroesophageal adenocarcinoma. Six-month PFS was 79%, surpassing our predefined efficacy end point, and median and 2-year OS were 16.8 months and 37%, respectively.

The role of surgery in the treatment of gastric cancer

During the past decades, despite considerable improvements in the management of gastric cancer, surgery remains the main curative treatment. However, there is still debate about the extent of gastrectomy and lymphadenectomy, multivisceral resection, the requirement for reoperation for specimens with positive margins, the selection of neoadjuvant treatment and the management strategy of early gastric cancer. This review is to evaluate the above issues based on the reported prospective and retrospective studies.

Safety and Feasibility of Carboplatin and Paclitaxel followed by Fluoropyrimidine Analogs and Radiation as Adjuvant Therapy for Gastric Cancer

Background

Adjuvant 5-fluorouracil (5FU)-based chemo-radiotherapy is currently considered a standard of care for the treatment of gastric cancer. The impact of 5FU-based adjuvant therapy on the rate of distant recurrence has been modest. In order to improve the systemic effects of adjuvant therapy, we have been treating patients with resected gastric cancer with carboplatin and paclitaxel followed by fluoropyrimidine analogue and radiation.

Methods

We report on the outcomes of 21 consecutive gastric cancer patients treated off protocol with adjuvant carboplatin (area under the curve 5 mg/ml × min) and paclitaxel (175–200 mg/m²) every 3 weeks, followed by concurrent pyrimidine analogs (either capecitabine 1,600–2,000 mg/m²/day in 17 patients, or 5FU 200 mg/m²/day in 4 patients) and radiation (45–50.4 Gy). Patients received a total of 4–6 cycles of carboplatin and paclitaxel.

Results

The median age at diagnosis was 60 years. Sixteen patients had stage 3 disease and 7 of them had positive surgical margins (6 with R1 and 1 with R2 resection), 3 patients were stage 2, and 2 patients were stage 1 (all had R0 resection). All patients had D1/D2 (4 had D2 and 17 had D1) lymph node dissection. The incidence of grade 3 or higher overall, hematologic, or gastrointestinal toxicity in the patients receiving carboplatin and paclitaxel was 57, 48 and 10%, respectively. No treatment-related deaths were observed. After adjuvant treatment 15 patients developed recurrent disease, 10 of whom had distant metastases. The median recurrence-free survival (RFS) was 12.3 months. The median overall survival (OS) was 16.0 months. Patients with R0 resection had significantly longer OS than did those with positive surgical margins (log-rank p = 0.0060). Median OS for the R0 resection group was 28.8 months.

Conclusions

Carboplatin and paclitaxel added to radiation plus fluoropyrimidine analogs is a well-tolerated regimen in the adjuvant setting. The activity of this regimen in this relatively high-risk group of gastric cancer patients is of interest for future development.

Pattern of lymph node involvement in proximal gastric cancer

BACKGROUND

The operative methods for proximal gastric cancer differ depending on the institution, thus there is no optimal therapeutic strategy. A splenic hilum lymph node (No. 10) dissection is necessary for D2 operation for proximal gastric cancer, which means it requires splenectomy. However, unnecessary splenectomy should be avoided.

METHODS

A total of 127 proximal gastric cancer cases from our institution were studied retrospectively. In addition, 1,569 cases were collected from the literature and were used as pooled data for further analysis. All cases were examined for the depth of tumor invasion and lymph node metastasis.

RESULTS

A retrospective analysis revealed that proximal gastric cancer within submucosa (40 cases) had no N2 lymph node metastasis in our study. The 5-year overall survival of all cases was 25.2% and the disease-free survival was 23.6%. From the pooled data analysis, No. 10 lymph node metastasis was observed in 0.9% of the patients with submucosa proximal gastric cancer. Furthermore, there was no No. 4d lymph node metastasis when the depth of cancer was limited to within the subserosa.

CONCLUSIONS

Although a randomized, controlled trial concerning survival is necessary, according to this study, there is a possibility that limited resection might be accepted for proximal gastric cancer according to the depth of wall invasion.

[Clinicopathological characteristics of Barrett's carcinoma, cardia carcinoma type II and distal gastric carcinoma: influence of observed parameters on the five-year postoperative survival of patients]

INTRODUCTION In the past two decades, the increased frequency of distal esophageal adenocarcinoma, esophagogastric junction and proximal gastric adenocarcinoma has been observed. The vast majority of these tumours are diagnosed in advanced stages, when the prognosis is poorer than in other gastric cancers.

OBJECTIVE

The aim of our study was to analyze the demographic and clinicopathological characteristics of patients operated on for Barrett's, cardia and distal gastric adenocarcinomas, as well as to study the influence of manifestations of each cancerogenetic indication on the studied clinicopathological parameters and to analyze the 5-year survival rate of patients surgically treated for cardia adenocarcinoma in relation to the patients operated on for distal gastric adenocarcinoma.

METHODS

We analyzed gender and age, tumour type, depth of tumour invasion, involvement of blood and lymph vessels in 66 patients surgically treated at the Centre for Oesophageal Surgery of the Institute for Digestive Diseases of the Belgrade Clinical Centre.

RESULTS

Except for significant differences in the depth of tumour invasion during surgery, there were no other statistically significant differences between the studied groups of patients. In the patients operated on for Barrett's and cardia cancers, the tumours invaded more deeply the wall layers, i.e. they were significantly more invasive than the distal gastric tumour. The lymph node involvement was present in 87.5% of patients with Barrett's cancer, in 80% with cardia cancer and in 87% with distal gastric cancer. The 3-year survival rate of patients operated on for cardia cancer was 47.4% and the 5-year survival rate was 31.6%, while the 3-year survival rate of patients operated on for distal gastric cancer was 46.2% and the 5-year survival rate was 34.6%. These differences were not statistically significant (Wilcoxon 0.036; p = 0.85). Singly, the patients' gender, cancer type and the degree of tumour differentiation had no influence on the length of patients' postsurgical survival rate.

CONCLUSION

At the time of diagnosis cardia cancer and cancers developed at the location of the Barrett's oesophagus, developed significant deeper per continuitatem than gastric cancer. There were no other differences in regard to the analyzed clinicopathological parameters among the tumours of these three locations, and there was no difference between the 3-year and 5-year survival rate between the patients operated on for gastric cancer and cardia cancer. Each studied clinicopathological parameter had no influence on the illness course.

Current strategies in systemic treatment of gastric cancer and cancer of the gastroesophageal junction

Gastric cancer is a major health issue and a leading cause of death worldwide. The results of standard therapy remain unsatisfactory mainly because of diagnosis at the late stage of disease. Innovative strategies such as neoadjuvant chemotherapy in locally advanced cancer have improved the outcome even in operable cases. Whether an adjuvant radiochemotherapy is of benefit after curative resection including systematic lymphadenectomy remains yet unclear. Some progress has been made in the palliative setting by introducing new substances. This review examines recent advances in the systemic treatment of gastric and gastroesophageal junction cancer.

Adenocarcinoma of the gastroesophageal junction: influence of esophageal resection margin and operative approach on outcome

OBJECTIVE

To determine whether the length of esophageal resection or the operative approach influences outcome for patients with adenocarcinoma of the gastroesophageal junction (GEJ).

SUMMARY BACKGROUND DATA

While R0 resection remains the mainstay of curative treatment of patients with GEJ cancer, the optimal length of esophageal resection remains controversial.

METHODS

Patients with Siewert I, II, or III adenocarcinoma who underwent complete gross resection without neoadjuvant therapy were identified from a prospectively maintained database. Proximal margin lengths were recorded ex vivo as the distance from the gross tumor edge to the esophageal transection line. Operative approaches were grouped into gastrectomy (limited esophagectomy) or esophagectomy (extended esophagectomy).

RESULTS

From 1985 through 2003, 505 patients underwent R0/R1 gastrectomy (n = 153) or esophagectomy (n = 352) without neoadjuvant treatment. There were no differences in R1 resection rate, number of nodes examined or operative mortality between gastrectomy and esophagectomy. Univariate analysis found >3.8 cm to be the ex vivo proximal margin length (approximately 5 cm in situ) most predictive of improved survival. Multivariable analysis in patients who underwent R0 resection with >or=15 lymph nodes examined (n = 275) found the number of positive lymph nodes, T stage, tumor grade, and ex vivo proximal margin length >3.8 cm to be independent prognostic factors. Subset analysis found that the benefit associated with >3.8 cm margin was limited to patients with T2 or greater tumors and <or=6 positive lymph nodes.

CONCLUSIONS

In patients not receiving neoadjuvant therapy, the goal for patients with adenocarcinoma of the GEJ should be R0 resection including at least 15 lymph nodes, preferably with 5 cm of grossly normal in situ proximal esophagus for those with <or=6 positive lymph nodes. The operative approach may be individualized to achieve these goals.

Systemic therapy for gastric cancer and adenocarcinoma of the gastroesophageal junction: present status and future directions

Gastric cancer is a major worldwide problem and is a leading cause of death. The incidence of distal gastric cancer is declining; however, there has been a rapid rise in the incidence of adenocarcinoma of the gastroesophageal junction, which is a more aggressive entity. Combination chemotherapy has significant activity in the treatment of both of these diseases, improving overall survival and quality of life. Despite these improvements, median survival remains at approximately 9 months in patients who are diagnosed at stage IV. This review examines recent advances in the treatment of gastroesophageal junction adenocarcinoma and gastric cancer, newer agents and the potential agents that are in development, which can be logically applied to the treatment of this devastating disease.

T4 gastric carcinoma: the benefit of non-curative resection

BACKGROUND

The prognosis of patients with gastric carcinoma with invasion of the adjacent organs (T4 gastric carcinoma) is very poor. We evaluated the survival benefit of resection in this group of patients.

METHOD

We retrospectively reviewed the hospital records of 288 patients with T4 gastric carcinoma to compare the clinicopathological results in patients with curative resection (n = 95) with patients with non-curative resection (n = 193) during the period 1986-2000.

RESULTS

With a 33% curative resectability in patients with T4 gastric carcinoma, patients with tumour resection (curative and non-curative) had a significantly improved survival rate. The overall survival rate was higher for patients who underwent resection (11.6%) than for patients who were not resected (2.5%), regardless of curability (P < 0.001). Using Cox's proportional hazard regression model, lymph node invasion and curability were independent statistically significant prognostic parameters. The prognosis of patients with invasion to the peritoneum and adrenal glands was significantly poorer than that of patients in whom there was no such invasion. But, the number of organs invaded had no effect on patient survival.

CONCLUSIONS

Patients with T4 gastric carcinoma might be benefited from curative resection. The results also emphasize the improved survivorship of T4 gastric carcinoma patients with resection compared with those who did not undergo resection. Although curative resection cannot be undertaken in patients with T4 gastric carcinoma, we recommend performing resection in patients with locally advanced gastric carcinoma, regardless of curability.

Clinicopathological significance and survival influence of p53 protein expression in gastric carcinoma

AIMS

Mutations in the gene coding for p53 protein are among the most frequent genetic alterations observed in human cancers. The relevance and biological significance of p53 expression in gastric carcinoma are far from being fully established. The aim of our study was to evaluate the influence of p53 detected by immunohistochemistry in the clinicopathological behaviour of a series of gastric carcinoma cases.

METHODS AND RESULTS

Samples from 163 patients treated by gastric resection for gastric carcinoma between 1988 and 1995 were used. Surgical specimens were evaluated for the presence of p53 protein detected by immunohistochemistry with a monoclonal antibody. Cases were classified as positive or negative for p53. Several clinicopathological parameters and c-erb B-2 expression were analysed in the same series and compared with the expression of p53. Cumulative survival was evaluated using univariate analysis and Cox model regression. p53 expression was identified in 41 carcinomas (25.2%) and was significantly associated with venous invasion (P = 0.049), lymph node metastases (P = 0.01) and c-erb B-2 expression (P = 0.003). All the parameters except gender, tumour size and Laurén's classification influenced survival on univariate analysis. p53 expression correlated with overall survival (P = 0.006) and survival in the subgroup of patients with intestinal type carcinoma (P = 0.04). In the subgroup of patients with carcinomas not expressing c-erb B-2, p53 expression significantly influenced cumulative survival (P = 0.02).

CONCLUSIONS

p53 expression is associated with the aggressive biological behaviour of gastric carcinomas and is related to cumulative survival.

Prognosis of T4 gastric carcinoma patients: an appraisal of aggressive surgical treatment

BACKGROUND AND OBJECTIVES

Despite precipitous drop in the incidence of gastric carcinoma in Japan, it is still one of the leading causes of death associated with malignant disease. Once the contiguous organs are involved the prognosis becomes dismal. Prognostic factors governing the survival of patients with T4 gastric carcinoma remain unclear.

METHODS

Between 1980 and 1998, 150 patients were treated for T4 gastric carcinoma. Results and prognostic factors were evaluated by univariate and multivariate analyses.

RESULTS

With a 73% resectability, patients with tumor resection had a significantly (P < 0.0001) improved survival rate. Within an acceptable operative mortality (2.6%), apparently curative cases had survival benefit (P < 0.0001) over noncurative cases. In the multivariate analysis, the death risk increased by 2.18 (relative risk) when splenectomy was spared from the operative procedure (P < 0.0071). Presence of esophageal invasion was the other independent prognostic factor in T4 gastric carcinoma patients (relative risk 2.11). Conventional prognostic factors along with the type of organs invaded by the carcinoma had no impact on prognosis.

CONCLUSIONS

Patients with T4 gastric carcinoma might be benefited from aggressive surgery with a curative intent. Whenever possible, splenectomy should be done along with invaded organ resection.

Surgical treatment of gastric cancer invading the oesophagus

INTRODUCTION

There is controversy regarding which type of surgical treatment is most appropriate for upper gastric cancer invading the oesophagus.

METHODS

A review of the pertinent literature was carried out regarding oesophageal involvement in gastric cancer.

RESULTS

Invasion of the oesophagus occurred in 26-63% of Western surgical series. It was more frequent in Borrmann IV type, linitis plastica, pT3-pT4, diffuse type by Lauren, N+ or tumours exceeding 5 cm in diameter. Lymphatic tumour spread was caudad (coeliac nodes, hepatoduodenal nodes, paraortic nodes) but mediastinal nodes were also involved if tumour growth in the oesophagus exceeded 3 cm or if there was transmural oesophageal infiltration. In Western countries there was less than 30% 5-year survival and no long-term survivors when hepatoduodenal or mediastinal nodes were metastatic. Mediastinal dissection through thoracotomy did not provide any benefit.

CONCLUSIONS

A rational approach involves total gastrectomy plus partial oesophagectomy. Abdominal transhiatal resection may be performed in the case of a localized, non-infiltrating tumour and oesophageal involvement <2 cm. However, infiltrating, poorly differentiated or Borrmann III-IV tumours require a right thoracotomy to achieve a longer margin of clearance. When oesophageal involvement is >3 cm, or hepatoduodenal or mediastinal nodes are positive, no surgical procedure is curative and the literature demonstrates that extended aggressive surgery has no benefits.

Proximal versus distal gastric carcinoma--what are the differences?

BACKGROUND

The incidence of proximal gastric third carcinoma (PGC) has been rising in recent years. Classification and surgical therapy remain controversial.

METHODS

Between May 1986 and October 1997, 532 patients were operated for primary gastric carcinoma. All patient data were analyzed retrospectively comparing findings in patients with PGC and those with distal gastric carcinoma (DGC).

RESULTS

Two hundred fifty patients had a PGC, and 282 patients had a DGC. The rate of RO resections was 79.3% for PGC and 81.6% for DGC. In 93.9% of the patients with PGC total gastrectomy was performed; for DGC total gastrectomy was done in 74.5% of patients. Postoperative morbidity and mortality were 29.2% for PGC and 23.8% for DGC, and 3.2% for PGC and 3.5% for DGC, respectively. Patients with advanced tumor stages (stage III and IV) were more common in the PGC group (73.3% vs. 53.6% in DGC). After RO resection, the 5-year survival rate was 33.2% for PGC and 59.7% for DGC.

CONCLUSIONS

There was no significant difference between the rates of RO resections for PGC and DGC. Total gastrectomy can be performed with low postoperative morbidity and mortality. PGC and DGC represent the same tumor entity, and prognosis is similar, but due to more advanced tumor stages, the long-term survival is worse for patients with PGC than for those with DGC. Left retroperitoneal lymphadenectomy may be indicated for PGC.

Adenocarcinoma of the gastroesophageal junction in Japan: relevance of Siewert's classification applied to 177 cases resected at a single institution

BACKGROUND

There had been a lack of international consensus about the definition of cancer of the gastric cardia until Siewert's classification was approved at a consensus conference during the second International Gastric Cancer Congress held in 1997.

STUDY DESIGN

A review of the prospective gastric cancer database at Aichi Cancer Center from 1983 to 1992 identified 1,913 gastric carcinoma patients who underwent gastrectomy. These patients were classified retrospectively according to the Siewert classification, and 177 patients who fell into one of the three types form the basis of this study. Survival analyses were performed after stratifying patients by clinicopathologic variables.

RESULTS

There were 33 patients with type II and 144 with type III, although none had type I, a type frequently observed in the west. No evidence of a change in the frequency of types II or III cancers (approximately 9.3% overall) among gastric carcinoma patients was observed over the 10-year period. Clinical staging of gastric carcinoma by the TNM classification was found to reflect accurately the prognosis of these patients. There were no longterm survivors among the few patients with metastasis to the perigastric nodes of the distal stomach.

CONCLUSIONS

A striking difference in the distribution of types of adenocarcinoma of the gastroesophageal junction was observed in Japan compared with previously reported western data. A subgroup of carcinoma of the proximal stomach identified as types II and III may not require proximal gastrectomy from the viewpoint of sufficient lymphadenectomy.

Surgical intervention and understanding of diseases of the stomach and duodenum

The stomach and duodenum are organs of complex physiology and cell biology. Neoplastic disease of these organs represents a difficult surgical challenge, and gastric and duodenal cancer mortality rates remain high despite advances in surgical technique, perioperative care, and adjuvant therapy. True "cures" elude the surgeon all too often. Fortunately, our understanding of the genetics and molecular biology of upper gastrointestinal neoplasms is increasing and is now significantly affecting the clinical management of these tumors as surgical therapies continue to improve. The care of benign disease of the stomach and duodenum is also evolving as medical therapy and surgical technology improve to lessen the morbidity associated with peptic ulcer disease and other benign conditions. The event that may have the greatest effect on surgical intervention in peptic ulcer disease is the Centers for Disease Control and Prevention launching of an educational campaign to promote treatment of Helicobacter pylori. This article reviews the most significant advances published in the past year on surgical intervention of the stomach and duodenum.