Changes of Esophagogastric Junctional Adenocarcinoma and Gastroesophageal Reflux Disease Among Surgical Patients During 1988-2012: A Single-institution, High-volume Experience in China

Laparoscopic splenic hilar lymph node dissection for advanced gastric cancer: to be or not to be

The incidence of proximal gastric cancer has increased in both the East and the West. Although some novel reconstructions like double-tract or double-flap anti-reflux procedure related to proximal gastrectomy are promising, total radical gastrectomy still accounts for a significant portion of these procedures. D2 radical gastrectomy is the globally accepted standard surgical procedure for advanced gastric cancer, and lymph node (LN) dissection is considered as the critical point of radical surgery and closely related to the prognosis. The splenic hilar LNs (No. 10) are LNs that need to be removed during standard D2 surgery for proximal and total gastrectomy. Lymphadenectomy does not only provide valuable information on the prognosis of gastric cancer, but the thoroughness of the sweep itself is directly related to postoperative survival. The incidence of splenic hilar LN (No. 10) metastasis rate is not high. Although the LN metastasis pathway around the spleen is complicated, the feasibility of laparoscopic splenic hilar LN dissection in locally advanced gastric cancer has been verified. However, these results are mostly from small volume clinical studies, and the fact is that the dissection of the splenic hilar is technique-demanding even for open surgery. The rational strategy for LN dissection for surgeons is still controversial. For splenic LN dissection in radical gastric cancer surgery, whether to select individualized splenic LN dissection for those patients highly suspected of clinical metastasis or to advocate the evidence-based strategy and neglect dissection in lower risk patients to avoid over-removing of LNs, is a vital question that needs to be clarified.

Comparison between gastric and esophageal classification system among adenocarcinomas of esophagogastric junction according to AJCC 8th edition: a retrospective observational study from two high-volume institutions in China

BACKGROUND

The new 8th TNM system attributes AEG Siewert type II to esophageal classification system. However, the gastric and esophageal classification system which was more suitable for type II remains in disputation. This study aimed to illuminate the 8th TNM-EC or TNM-GC system which was more rational for type II, especially for patients underwent transhiatal approaches.

METHODS

We collected the database of patients with AEG who underwent radical surgical resection from two high-volume institutions in China: West China Hospital (N = 773) and Xi Jing Hospital of Fourth Military University (N = 637). The cases were randomly matched into 705 training cohort and 705 validation cohort. All the cases were reclassified by the 8th edition of TNM-EC and TNM-GC. The distribution of patients in each stage, the hazard ratio of each stage, and the separation of the survival were compared. Multivariate analysis was performed using the Cox proportional hazard model. Comparisons between the different staging systems for the prognostic prediction were performed with the rcorrp.cens package in Hmisc in R (version 3.4.4. http://www.R-project.org/ ). The validity of these two systems was evaluated by Akaike information criterion (AIC) and concordance index (C-index).

RESULTS

By univariate analysis, the HRs from stage IA/IB to stage IV/IVB were monotonously increased according to TNM-GC scheme in both cohorts (training 2.63, 3.91, 5.02, 8.64, 15.51 and 29.64; validation 1.54, 3.55, 4.91, 7.14, 11.67, 18.71 and 48.32) whereas only a fluctuating increased tendency was found when staged by TNM-EC. After the multivariate analysis, TNM-GC (P < 0.001), TNM-EC (P = 0.001) in training cohort and TNM-GC (P < 0.001) TNM-EC (P < 0.001) in the validation cohort were both independent prognostic factors. The C-index value for the TNM-GC scheme was larger than that of TNM-EC system in both training (0.721 vs. 0.690, P < 0.001) and validation (0.721 vs. 0.696, P < 0.001) cohorts. After stratification analysis for Siewert type II, the C-index for TNM-GC scheme was still larger than that of TNM-EC in both training (0.724 vs. 0.694, P = 0.005) and validation (0.723 vs. 0.699, P < 0.001) cohorts.

CONCLUSIONS

The 8th TNM-GC scheme is superior to TNM-EC in predicting the prognosis of AEG especially for type II among patients underwent transhiatal approaches.

Optimal Extent of Transhiatal Gastrectomy and Lymphadenectomy for the Stomach-Predominant Adenocarcinoma of Esophagogastric Junction: Retrospective Single-Institution Study in China

Background: The optimal extent of gastrectomy and lymphadenectomy for esophagogastric junction (EGJ) cancer is controversial. Our study aimed to compare the long-term survival of transhiatal proximal gastrectomy with extended periproximal lymphadenectomy (THPG with EPL) and transhiatal total gastrectomy with complete perigastric lymphadenectomy (THTG with CPL) for patients with the stomach-predominant EGJ cancer. Methods: Between January 2004, and August 2015, 306 patients with Siewert II tumors were divided into the THTG group (n = 148) and the THPG group (n = 158). Their long-term survival was compared according to Nishi's classification. The Kaplan-Meier method and Cox proportional hazards models were used for survival analysis. Results: There were no significant differences between the two groups in the distribution of age, gender, tumor size or Nishi's type (P > 0.05). However, a significant difference was observed in terms of pathological tumor stage (P < 0.05). The 5-year overall survival rates were 62.0% in the THPG group and 59.5% in the THTG group. The hazard ratio for death was 0.455 (95% CI, 0.337 to 0.613; log-rank P < 0.001). Type GE/E = G showed a worse prognosis compared with Type G (P < 0.05). Subgroup analysis stratified by Nishi's classification, Stage IA-IIB and IIIA, and tumor size ≤ 30 mm indicated significant survival advantages for the THPG group (P < 0.05). However, this analysis failed to show a survival benefit in Stage IIIB (P > 0.05). Conclusions: Nishi's classification is an effective method to clarify the subdivision of Siewert II tumors with a diameter ≤ 40 mm above or below the EGJ. THPG with EPL is an optimal procedure for the patients with the stomach-predominant EGJ tumors ≤30 mm in diameter and in Stage IA-IIIA. For more advanced and larger EGJ tumors, further studies are required to confirm the necessity of THTG with CPL.

Novel abdominal approach for dissection of advanced type II/III adenocarcinoma of the esophagogastric junction: a new surgical option

OBJECTIVE

The optimal surgical approach for Siewert type II adenocarcinoma of the esophagogastric junction (AEG) is controversial. In this study, we evaluated the outcomes of total gastrectomy for Siewert type II/III AEG via the left thoracic surgical approach that is used at our center.

METHODS

We identified 41 patients with advanced AEG in our retrospective database and analyzed their 3-year survival rate, upper surgical margin, postoperative complications, and index of estimated benefit from lymph node dissection.

RESULTS

The 3-year overall survival rate of the whole group was 63%, but no difference was observed between Siewert type II and III AEGs. Esophageal exposure and lymphadenectomy were sufficient. Eight patients developed postoperative complications, but none of the patients developed anastomotic leakage. Dissection of lymph node station Nos. 19 and 110 may be necessary for patients with Siewert type II AEG. Multivariate analysis revealed that the cT category was the only independent risk factor.

CONCLUSIONS

Total gastrectomy via an approach from the abdominal cavity into the thoracic cavity may be an optimal surgical technique for advanced Siewert type II AEG.

Robotic-assisted gastrectomy for gastric cancer: a European perspective

Gastrectomy is the mainstay treatment for gastric cancer. To reduce the associated patient burden, minimally invasive gastrectomy was introduced in almost 30 years ago. The increase in the availability of surgical robotic systems led to the first robotic-assisted gastrectomy to be performed in 2002 in Japan. Robotic gastrectomy however, particularly in Europe, has not yet gained significant traction. Most reports to date are from Asia, predominantly containing observational studies. These cohorts are commonly different in the tumour stage, location (particularly with regards to gastroesophageal junctional tumours) and patient BMI compared to those encountered in Europe. To date, no randomised clinical trials have been performed comparing robotic gastrectomy to either laparoscopic or open equivalent. Cohort studies show that robotic gastrectomy is equal oncological outcomes in terms of survival and lymph node yield. Operative times in the robotic group are consistently longer compared to laparoscopic or open gastrectomy, although evidence is emerging that resectional surgical time is equal. The only reproducibly significant difference in favour of robot-assisted gastrectomy is a reduction in intra-operative blood loss and some studies show a reduction in the risk of pancreatic fistula formation.

Study on safety of laparoscopic total gastrectomy for clinical stage I gastric cancer: the protocol of the CLASS02-01 multicenter randomized controlled clinical trial

BACKGROUND

The safety of laparoscopic total gastrectomy (LTG) for the treatment of gastric cancer remains lack of clinical evidence. The Chinese Laparoscopic Gastrointestinal Surgery Study (CLASS) Group recently launched a multicenter randomized clinical trial (CLASS02-01) to compare the safety of LTG for clinical stage I gastric cancer with the conventional open total gastrectomy (OTG).

METHODS

This CLASS02-01 trial is a prospective, multicenter, randomized, controlled, open, and non-inferiority trial. Two hundred patients who met the inclusion criteria and did not accord with the exclusion criteria will be randomly divided into LTG group (n = 100) and OTG group (n = 100). The primary purpose of this study is to evaluate the early operative morbidity and mortality of LTG compared with OTG for clinical stage I gastric adenocarcinoma. The second purpose is to evaluate the recovery course and compare the postoperative hospital stay of the patients enrolled in this study.

DISCUSSION

This CLASS02-01 trial is the first prospective randomized two-arm controlled study to determine the safety of LTG compared with OTG. Through this trial, we hope to show that experienced surgeons can safely perform LTG with lymphadenectomy for gastric cancer.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03007550 . December 30, 2016.

Characteristics and survival outcomes related to the infra-pyloric lymph node status of gastric cancer patients

BACKGROUND

To study metastasis to the infra-pyloric (no. 6) lymph nodes and their subgroups and the related risk factors of gastric cancer patients.

METHODS

Gastric cancer patients who underwent gastrectomy with complete postoperative pathological information on the no. 6 lymph node station and its subgroups from January 1, 2008, to December 31, 2011, were included. The clinicopathological characteristics and survival outcomes were analyzed.

RESULTS

A total of 121 patients were included; they had 6.1 ± 7.7 positive lymph nodes, and 35.1 ± 14.2 lymph nodes were examined. The overall lymph node positivity rate was 67.8% (82/121) with a positivity rate of 28.1% (34/121) for the no. 6 lymph nodes. The metastasis rate was 6.6% for the no. 6a nodes, 6.6% for the no. 6b nodes, and 21.5% for the no. 6c nodes. Also, no. 8a (OR = 1.329, p = 0.017) and no. 9 (OR = 1.250, p = 0.022) nodal positivity and lower third tumor location (OR = 1.278, p = 0.001) were independent risk factors for no. 6 lymph nodal metastasis. There was a significant survival difference between patients with positive and negative no. 6 lymph nodes and patients with metastasis to other lymph node stations (p <  0.001).

CONCLUSIONS

Patients with no. 6 lymph node metastasis have poor survival outcomes. Complete infra-pyloric lymphadenectomy is necessary and crucial for gastric cancer patients.

A network meta-analysis of the short-term efficacy of five chemotherapy regimens based on cisplatin and fluorouracil for esophagogastric junctional adenocarcinoma

The primary purpose of this study was to explore the short-term efficacy of different cisplatin and fluorouracil-based chemotherapy regimens in the treatment of patients with esophagogastric junctional adenocarcinoma (EGJA) using a network meta-analysis (NMA). Randomized controlled trials (RCTs) related to chemotherapy regimens based on cisplatin and fluorouracil for EGJA were included from the PubMed, EMBASE and Cochrane Library electronic databases (from inception to June 2016). Direct and indirect evidence were combined to calculate the pooled odds ratio (OR) and its 95% confidence interval (95% CI) as well as to draw the surface under the cumulative ranking (SUCRA) curves. This NMA finally enrolled ten eligible RCTs with the following five regimens: cisplatin plus fluorouracil (cisplatin+fluorouracil), cisplatin+fluorouracil-based chemotherapy (cisplatin+fluorouracil+docetaxel/epirubicin/irinotecan), fluorouracil-based chemotherapy (fluorouracil+docetaxel/doxorubicin/methotrexate/irinotecan), cisplatin-based chemotherapy (cisplatin+docetaxel/epirubicin/irinotecan/capecitabine/s-1) and other drug-based chemotherapy (docetaxel/irinotecan/capecitabine). These results revealed that compared with a cisplatin+ fluorouracil-based chemotherapy regimen, the fluorouracil-based chemotherapy regimen had a lower overall response rate (ORR) and partial response (PR) for EGJA patients (ORR: OR=0.43, 95% CI=0.22-0.86; PR: OR=0.46, 95% CI=0.23-0.91). Cluster analyses suggested that the cisplatin+fluorouracil-based chemotherapy regimen had the best short-term efficacy for EGJA in terms of the complete response (CR), PR, ORR, stable disease (SD) and progression disease (PD). Our results indicated that cisplatin+fluorouracil-based chemotherapy regimens may have the best short-term efficacy in the treatment of EGJA.

Association between Paraoxonase 1 polymorphisms and risk of esophagogastric junction adenocarcinoma: a case-control study involving 2,740 subjects

Esophagogastric junction adenocarcinoma (EGJA) is a serious public health problem with high mortality in China. In this study, we assessed the association between Paraoxonase 1 (PON-1) rs662 C>T, rs854560 A>T polymorphisms and EGJA risk. This case-control study enrolled 2,740 participants of Asians origin from the Eastern Chinese Han populations. SNPscanTM genotyping assay was harnessed to determine the genotyping of PON1 polymorphisms. The PON-1 rs854560 A>T and rs662 C>T genotypes distribution accorded with Hardy–Weinberg equilibrium. We found that there was no difference in the frequency of PON-1 rs662 C>T, rs854560 A>T genotypes between the overall EGJA cases and controls. In the subgroup analyses, the results indicated that PON-1 rs662 C>T polymorphism might be associated with a significantly decreased risk of EGJA in ever smoking group (TT vs. CC/CT: adjusted OR = 0.58, 95% CI 0.35–0.95, P = 0.029). In conclusion, our study highlights PON-1 rs662 C>T polymorphism may decrease the risk of EGJA, which interacts with the tobacco using. In the future, a fine-mapping case-control study with detailed gene-environmental data is needed to further assess these potential relationship.

Comparisons of short-term and survival outcomes of laparoscopy-assisted versus open total gastrectomy for gastric cancer patients

OBJECTIVES

The safety and surgical oncology of laparoscopy-assisted total gastrectomy (LATG) remain inconclusive and challenging. This study aimed to compare the short-term and long-term outcomes between LATG and open total gastrectomy (OTG) procedures.

RESULTS

In the all-included analyses, there were 69 patients in the LATG group and 268 in the OTG group. LATG was as safe as OTG without increasing postoperative morbidity and mortality. Stage imbalance might introduce differences in the numbers of harvested lymph nodes in LATG (34.4 ± 12.0) and OTG (40.9 ± 16.9), whereas 95.7% of patients underwent D2/D2+ dissection during the LATG procedure. After a median 31 months of follow-up, the overall survival outcomes were comparable between the LATG and OTG procedures (HR = 1.16, 95% CI 0.68-1.97). Sensitivity analysis found comparable node retrieval and stage-specific or treatment-specific overall survival.

MATERIALS AND METHODS

A retrospective case-control study was conducted among gastric cancer patients who underwent either LATG or OTG with curative intention between June 2006 and December 2015. Data retrieval was based on the Surgical Gastric Cancer Patient Registry in the West China Hospital. The primary outcome was overall survival. The secondary outcomes were postoperative complication incidence and severity, operation duration, blood loss, number of harvested lymph nodes, and postoperative hospital stay. Matched pairwise case-control comparisons were performed as a sensitivity analysis.

CONCLUSIONS

LATG by experienced surgeons possibly has comparable short-term surgical outcomes and long-term survival outcomes compared with OTG for gastric cancer patients. However, high-quality RCTs are necessary before confirmative judgment and recommendation as an optional treatment in general practice.

Omeprazole promotes carcinogenesis of fore-stomach in mice with co-stimulation of nitrosamine

Objectives

To investigate if oral omeprazole application induces cancers of fore and glandular stomach in mice.

Methods

A total of 66 eligible male mice were randomly divided into 6 groups, which were treated with control reagent, low (6 mg/kg) and high dose omeprazole (30 mg/kg), N-methyl-N’-nitro-N-nitrosoguanidine (MNNG, 100 mg/L water), and MNNG plus low and high dose omeprazole, respectively. After 24 weeks, concentrations of acid phosphatase (ACP) and N-acetyl-β-D-glucosaminidase(NAG) in serum and spleen was examined, and p21 and mTOR levels in stomach were detected.

Results

The mouse spleen weight index was smaller in the omeprazole group than the control group, and in the MNNG plus omeprazole groups than the MNNG group. In the fore-stomach, more carcinomas were observed in the MNNG plus omeprazole groups than in the MNNG group. In the glandular stomach, there existed more atypical hyperplasia cases in the MNNG plus omeprazole groups than the MNNG-treated group, and one carcinoma was induced in the MNNG plus high dose omeprazole group. Omeprazole alone caused minor gastric pathological changes. Omeprazole treatment lowered both serum and spleen ACP and NAG levels in both the non-MNNG-treated and MNNG-treated subgroups. In fore-stomach, there existed decreased p21 and mTOR levels in the omeprazole-treated groups than in the control group, and in the MNNG plus omeprazole groups than the MNNG-treated group.

Conclusion

Omeprazole promotes carcinogenesis of the mouse fore-stomach but not the glandular stomach following treatment with MNNG. Lysosomal hydrolase activity was inhibited and some cancer-associated proteins was dysregulated, which requires further explorations.

Lymph node dissection for Siewert II esophagogastric junction adenocarcinoma: a retrospective study of 136 cases

BACKGROUND

To compare the lymph node dissection with the right transthoracic Ivor-Lewis (IL) procedure to that with the left transthoracic (LT) approach for Siewert type II adenocarcinoma of the esophagogastric (AEG) junction.

METHODS

In this study, 136 patients with Siewert type II AEG who met the inclusion criteria underwent surgical resection were divided into the IL (47 cases) and LT (89 cases) groups. The number and frequency of the dissected lymph nodes in each station were compared between the two groups.

RESULTS

The IL group had a longer proximal surgical margin (P = 0.000) and more total (P = 0.000), thoracic (P = 0.000), and abdominal lymph nodes (P = 0.000) dissected than the LT group. In general, the IL group had a higher dissection rate in each thoracic lymph node station (P < 0.05) than the LT group. The dissection rates of the hepatic artery, splenic artery and celiac trunk lymph nodes were higher in the IL group than in the LT group (P < 0.05). The lymph node metastasis rate was 78.7% in the IL group, higher than the 61.8% in the LT group (P = 0.045).

CONCLUSIONS

The right transthoracic IL procedure was demonstrated to be a better application than the LT approach for Siewert type II AEG in terms of the number and frequency of lymph node resections.

Gastric cancer treatment: similarity and difference between China and Korea

Chinese populations have many demographic similarities to Korean populations. However, the long-term survival rates of gastric cancer patients in China are still not satisfactory when compared with Korea, especially for the advanced cases. In this article, we discuss about the similarity and difference of gastric cancer treatment in terms of screening, surgical approach, stomach resection, digestive tract reconstruction, lymphadenectomy, harvested lymph nodes, operative morbidity and mortality, postoperative chemotherapy as well as follow-up between China and Korea. Given that a variety of factors ranging from tumor characteristics to different treatment strategies are seen between the two countries, the reasons accounting for the differences in survival should be focused and the corresponding strategy should be considered and finally promote to improve the prognosis of gastric cancer.

Lymph node dissection for Siewert II esophagogastric junction adenocarcinoma: A retrospective study of 3 surgical procedures

The present study was aimed to investigate the application of right thansthoracic Ivor-Lewis (IL), left transthoracic (LTT), and left thoracoabdominal (LTA) approach in Siewert type II adenocarcinoma of esophagogastric junction (AEG).The data of 196 patients with Siewert type II AEG received surgical resection in our cancer center between January 2014 and April 2016 was retrospectively analyzed. Finally, 136 patients met the inclusion criteria were enrolled in the study and divided into the IL (47 cases), LTT (51 cases), and LTA group (38 cases). Clinical and short-term treatment effects were compared among the 3 groups.The patients with weight loss, diabetes, and heart disease increased in the LTT group (P = 0.054, P = 0.075, and P = 0.063, respectively). Operation time was significantly longest in the IL group (P < 0.001), but the amount of bleeding and tumor size did not significantly differ among the 3 groups (P = 0.176 and P = 0.228, respectively). The IL group had the significantly longest proximal surgical margin (P < 0.001) and most number of total (P < 0.001) and thoracic lymph nodes (P < 0.001) dissected. Both the IL and LTA groups had more abdominal lymph nodes dissected than the LTT group (P < 0.001). In general, the IL and LTT groups had the highest dissection rates of every station of thoracic (P < 0.05) and lower mediastinal lymph nodes (P < 0.05), respectively. The dissection rate of the paracardial, left gastric artery, and gastric lesser curvature lymph nodes did not differ significantly among the 3 groups (P > 0.05), but the dissection rate of the hepatic artery, splenic artery, and celiac trunk lymph nodes was significantly highest in the IL group (P < 0.05). Postoperative hospital stay, perioperative complications, and mortality did not differ significantly among the 3 groups (P > 0.05).Compared with the traditional left transthoracic approach, the Ivor-Lewis approach did not increase the perioperative mortality and complication rates in Siewert type II AEG, but obtained satisfactory length of the proximal surgical margin, and was better than the left transthoracic approach in thoracic and abdominal lymph node dissection. However, the advantages of Ivor-Lewis procedure requires further follow-up and validation through prospective randomized controlled trials.

Learning curve for gastric cancer patients with laparoscopy-assisted distal gastrectomy: 6-year experience from a single institution in western China

Laparoscopy-assisted distal gastrectomy (LADG) is widely used for gastric cancer (GC) patients nowadays. This study aimed to investigate the time trend of outcomes so as to describe the learning curve for GC patients with LADG at a single medical institution in western China over a 6-year period.A total of 246 consecutive GC patients with LADG were divided into 5 groups (group A: 46 patients from 2006 to 2007; group B: 47 patients in 2008; group C: 49 patients in 2009; group D: 73 patients in 2010; and group E: 31 patients in 2011). All surgeries were conducted by the same surgeon. Comparative analyses were successively performed by Mann-Whitney U test or Student t test among the 5 different groups for the clinical data, including clinicopathologic characteristics, surgical parameters, postoperative course, and survival outcomes, through which the learning curve was described.There were no differences in the baseline information among the 5 groups (P > 0.05), and the proportion of advanced GC patients with LADG slightly increased from 58.7% to 77.4% during the 6 years. Besides, the proportion of D2/D2+ lymphadenectomy and the number of retrieved lymph nodes gradually grew from 60.9% to 80.6% and from 20.0 to 28.8, respectively. In addition, the operation time decreased from 299.2 to 267.8 minutes, while the estimated blood loss dropped from 175.2 to 146.8 mL. Furthermore, some surgical parameters (surgical duration and blood loss) and postoperative course (such as postoperative complications, the time to ambulation, to first flatus, and to first liquid intake as well as the length of hospital stay) were all observed to be significantly different between group A and other groups (P < 0.05), illustrating a similar downward trend and remaining stable to form a plateau after 46 cases in group A. However, no difference on overall survival was found among these 5 groups, and multivariate analysis indicated that factors, such as age, tumor differentiation, tumor size, and T stage as well as N stage, were independent prognostic factors for patients with LADG.Improvement on surgical parameters and postoperative course can be seen over the past years, and the cutoff value of the learning curve of LADG for surgeons with rich experience in open operation might be 46 cases.

Comparison of survival outcomes between transthoracic and transabdominal surgical approaches in patients with Siewert-II/III esophagogastric junction adenocarcinoma: a single-institution retrospective cohort study

OBJECTIVE

To compare the survival outcomes of transabdominal (TA) and transthoracic (TT) surgical approaches in patients with Siewert-II/III esophagogastric junction adenocarcinoma.

METHODS

This retrospective study was conducted in patients with Siewert-II/III esophagogastric junction adenocarcinoma who underwent either TT or TA operations in the West China Hospital between January 2006 and December 2009.

RESULTS

A total of 308 patients (109 in the TT and 199 in the TA groups) were included in this study with a follow-up rate of 87.3%. The median (P25, P75) number of harvested perigastric lymph nodes was 8 (5, 10) in the TT group and 23 (16, 34) in the TA group (P<0.001), and the number of positive perigastric lymph nodes was 2 (0, 5) in the TT group and 3 (1, 8) in the TA group (P<0.004). The 5-year overall survival (OS) rate was 36% in the TT group and 51% in the TA group (P=0.005). Subgroup analysis by Siewert classification showed that 5-year OS rates for patients with Siewert II tumors were 38% and 48% in TT and TA groups, respectively (P=0.134), whereas the 5-year OS rate for patients with Siewert III tumors was significantly lower in the TT group than that in the TA group (33% vs. 53%; P=0.010). Multivariate analysis indicated that N2 and N3 stages, R1/R2 resection and a TT surgical approach were prognostic factors for poor OS.

CONCLUSIONS

Improved perigastric lymph node dissection may be the main reason for better survival outcomes observed with a TA gastrectomy approach than with TT gastrectomy for Siewert III tumor patients.

Strategies to improve treatment outcome in gastric cancer: a retrospective analysis of patients from two high-volume hospitals in Korea and China

China has high incidence of gastric cancer (GC). However, the treatment outcomes of China were unsatisfactory compared to those of Korea. We performed this study to compare tumour characteristics, treatment parameters, and survival outcomes of GC patients between Korea and China based on the databases of two high-volume hospitals, with the aim of identifying indicators of GC prognosis. Data of patients undergoing gastrectomy for GC from 2006 to 2010 were analysed retrospectively. Subgroup survival analyses, stratified by clinicopathologic factors and multivariable analyses, were performed. The interactive roles of chemotherapy and D2 lymphadenectomy for overall survival were also investigated. Among 1365 Chinese and 4981 Korean patients, the proportion of early cancer detection in Chinese patients was much lower relative to that of Korean patients. There were no significant differences between countries in terms of surgical morbidity and mortality. The overall 5-year survival rates were 54.3% and 81.4%; when stratified by clinicopathologic factors, the survival were generally statistically higher in Korean patients. Gender, age, T stage, N stage, extent of lymphadenectomy, radicality of surgery, resection type, and chemotherapy were independently associated with survival in patients without metastasis. Survival rates for stage II and III GC differed significantly between the two countries, but this difference was eliminated among patients who underwent D2 lymphadenectomy or received chemotherapy. These treatments were given to patients with advanced-stage diagnoses (approximately 20% and 80% of patients, respectively). Treatment type was selected as independent prognostic factors in stage I-III and D2/D2+, with chemotherapy resulting in the best prognosis. Many differences in GC tumour characteristics exist between two countries. Early cancer detection and standardized treatment in Korea contribute to superior survival rates. Promotion of an early screening program, training and dissemination of standard D2 lymphadenectomy, and appropriate applications of chemotherapy would improve survival outcomes.