Treatment strategy of limited surgery in the treatment guidelines for gastric cancer in Japan

Reflux Esophagitis After Laparoscopic Pylorus-Preserving Gastrectomy for Gastric Cancer

BACKGROUND

Laparoscopic pylorus-preserving gastrectomy (LPPG) is performed for cT1N0 gastric cancer as a function-preserving surgery, but reflux esophagitis can develop as a mid- to long-term complication postoperatively. We aimed to clarify the incidence rate of this complication and the factors correlated with it.

METHODS

Patients with gastric cancer who underwent LPPG between 2005 and 2017 were analyzed. Postoperative reflux esophagitis was evaluated with esophagogastroduodenoscopy; patients were diagnosed as having reflux esophagitis with erosive esophagitis using the modified Los Angeles classification. The incidence rate of postoperative reflux esophagitis was estimated; factors correlated with postoperative reflux esophagitis were analyzed using the logistic regression model.

RESULTS

During the study period, 813 patients underwent LPPG for gastric cancer, and 127 (15.6%) of them developed grade B or more severe postoperative reflux esophagitis. The factors correlated with postoperative reflux esophagitis were male sex (odds ratio, 2.68; 95% confidence interval, 1.77-4.05; P < 0.001), preoperative grade A reflux esophagitis (odds ratio, 3.05; 95% confidence interval, 1.28-7.27; P = 0.012), body mass index of ≥ 23 kg/m² at 1 year postoperatively (odds ratio, 2.18; 95% confidence interval, 1.34-3.53; P = 0.002), postoperative hiatal hernia (odds ratio, 4.35; 95% confidence interval, 2.35-8.04; P < 0.001), and long-term stasis (odds ratio, 1.58; 95% confidence interval, 1.01-2.47; P = 0.044).

CONCLUSIONS

Careful attention should be paid in performing LPPG and in postoperative management after LPPG for gastric cancer patients with those risk factors.

Prognostic Model and Immune Infiltration of Ferroptosis Subcluster-Related Modular Genes in Gastric Cancer

Background

Gastric cancer (GC) is one of the gastrointestinal tumors with the highest mortality rate. The number of GC patients is still high. As a way of iron-dependent programmed cell death, ferroptosis activates lipid peroxidation and accumulates large reactive oxygen species. The role of ferroptosis in GC prognosis was underrepresented. The objective was to investigate the role of ferroptosis-related genes (FRGs) in the prognosis and development of GC.

Methods

Datasets of GC patients were obtained from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) database that include clinical information and RNA seq data. Through nonnegative matrix factorization (NMF) clustering, we identified and unsupervised cluster analysis of the expression matrix of FRGs. And we constructed the co-expression network between genes and clinical characteristics by consensus weighted gene co-expression network analysis (WGCNA). The prognostic model was constructed by univariate and multivariate regression analysis. The potential mechanisms of development and prognosis in GC were explored by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, gene ontology (GO), tumor immune microenvironment (TIME), and tumor mutation burden (TMB).

Results

Two molecular subclusters with different expression patterns of FRGs were identified, which have significantly different survival states. Ferroptosis subcluster-related modular genes were identified by WGCNA. Based on 8 ferroptosis subcluster-related modular genes (collagen triple helix repeat containing 1 (CTHRC1), podoplanin (PDPN), procollagen-lysine,2-oxoglutarate 5-dioxygenase 2 (PLOD2), glutamine-fructose-6-phosphate transaminase 2 (GFPT2), ATP-binding cassette subfamily A member 1 (ABCA1), G protein-coupled receptor 176 (GPR176), serpin family E member 1 (SERPINE1), dual specificity phosphatase 1 (DUSP1)) and clinicopathological features, a nomogram was constructed and validated for their predictive efficiency on GC prognosis. Through receiver operating characteristic (ROC) analysis, the results showed that the area under the curve (AUC) of 1-, 3-, and 5-year survival were 0.721, 0.747, and 0.803, respectively, indicating that the risk-scoring model we constructed had good prognosis efficacy in GC. The degree of immune infiltration in high-risk group was largely higher than low-risk group. It indicated that the immune cells have a good response in high-risk group of GC. The TMB of high-risk group was higher, which could generate more mutations and was more conducive to the body's resistance to the development of cancer.

Conclusion

The risk-scoring model based on 8 ferroptosis subcluster-related modular genes has shown outstanding advantages in predicting patient prognosis. The interaction of ferroptosis in GC development may provide new insights into exploring molecular mechanisms and targeted therapies for GC patients.

Taste alteration after gastrectomy in patients with gastric cancer

PURPOSE

To investigate the relationship between changes in taste due to surgical procedures and other clinical factors, we performed a detailed investigation of taste alteration in patients who underwent gastrectomy.

METHODS

Questionnaires on taste alteration were distributed to patients who visited our outpatient clinic from July 2018 to January 2019 for the postoperative evaluation of gastric cancer. Associations of clinical characteristics with changes in sensitivity to the four major taste types (sweet, sour, salty, and bitter) were examined.

RESULTS

Of the 243 eligible patients, 42 (17.3%) experienced taste alteration after gastrectomy; taste sensitivity decreased in 21 (8.6%) patients and increased in 31 (12.7%) patients. The frequency of a decreased sensitivity to sweet was significantly higher in patients who underwent total gastrectomy than in those who underwent distal gastrectomy (18.8% vs. 3.3%, P = 0.001). Patients who underwent total gastrectomy were significantly more likely than those who received distal gastrectomy to experience increased sensitivity to sour (12.5% vs. 2.2%, respectively; P = 0.004) and bitter (15.6% vs. 3.8%, respectively; P = 0.007) tastes. A multivariate analysis revealed that total gastrectomy was an independent risk factor for total taste alteration.

CONCLUSIONS

Patients who underwent total gastrectomy showed a high likelihood of both loss and gain of taste sensitivity.

Risk and treatment of non-hepatic cancers in patients with cirrhosis

Patients with cirrhosis are at a high risk for hepatocellular carcinoma. However, it remains controversial about whether or not there is a high risk for non-hepatic cancers in patients with liver cirrhosis. Additionally, the management of non-hepatic cancers in cirrhotic patients is a clinical challenge, because the use of surgery and anticancer drugs is often compromised by the presence of liver dysfunction. This editorial aims to briefly summarize the findings on the risk and management of non-hepatic cancers in patients with cirrhosis.

Risk factors and prognosis of gastric stasis, a crucial problem after laparoscopic pylorus-preserving gastrectomy for early middle-third gastric cancer

BACKGROUND

Pylorus-preserving gastrectomy (PPG) is a function-preserving procedure for cT1N0 gastric cancer located in the middle-third of stomach, which is currently performed through a laparoscopic approach (LPPG). PPG is sometimes associated with a crucial problem during the early postoperative course, designated gastric stasis. However, information regarding gastric stasis remains to be fully elucidated.

METHODS

The study included 897 patients who underwent LPPG between 2005 and 2017. Early postoperative gastric stasis (E-stasis) was defined when the following conditions were fulfilled: upper abdominal distension, remnant stomach fullness on radiography image, and period of starvation exceeding 72 h within 1 month postoperatively. To evaluate long-term outcomes of E-stasis, late postoperative food residue (L-residue) was defined as grade 2 or higher food residue endoscopically according to the RGB (residue, gastritis, bile) classification at 1 year postoperatively. Risk factors and long-term outcomes of E-stasis were retrospectively analyzed.

RESULTS

E-stasis was the most common complication during the early postoperative course. E-stasis occurred in 68 (7.6%) patients. Multivariate analysis identified age (≥ 61 years), DM, and postoperative intraabdominal infection as risk factors. At 1 year postoperatively, relative body weight ratio and postoperative serum albumin in the patients who experienced E-stasis was significantly lower than those in the other patients (P = 0.042 and 0.011, respectively). Of the patients who suffered from E-stasis, 42.5% experienced L-residue.

CONCLUSIONS

E-stasis after LPPG occurs in 7.6% of patients. Age, DM, and intraabdominal infection are significantly related to E-stasis. E-stasis is associated with poorer nutritional and functional outcomes even at 1 year postoperatively.

Functional and nutritional outcomes after gastric cancer surgery

Recent improvements in diagnostic techniques and national screening programs have resulted in increasing number of patients diagnosed with early gastric cancer (EGC). The low incidence rate of lymph node metastasis and excellent survival rates after surgical treatment for EGC enabled the reduction in the extent of lymphadenectomy and the range of gastric resection for function-preserving gastrectomy. Thus, the quality of life (QOL) of patients with gastric cancer (GC) in the curative stage can be maintained. Moreover, these function-preserving procedures have been widely performed by less invasive procedures, such as laparoscopic and robotic approaches. Pylorus-preserving gastrectomy (PPG) and proximal gastrectomy (PG) represent the two main function-preserving surgical procedures for GC. PPG is an alternative to distal gastrectomy (DG) for cT1 N0 EGC located in the middle part of the stomach. Preservation of the pyloric function is expected to prevent post-gastrectomy syndromes such as dumping syndrome. PG is an alternative to total gastrectomy (TG) and can thus be performed for cT1 N0 EGC located in the upper part of the stomach. Preservation of the residual stomach is expected to work as a reservoir for ingested food. The optimal reconstruction method after PG among the three most commonly performed procedures (esophagogastrostomy, jejunal interposition, and double-tract reconstruction) remains controversial. In addition to these three reconstruction methods, the novel double-flap technique (DFT) of esophagogastrostomy has gained attention recently because of its potential usefulness to prevent postoperative esophageal reflux. In this review article, we summarize the current evidence of PPG and PG with esophagogastrostomy by the DFT, focusing on postoperative nutrition and QOL.

Impact of capillary invasion on the prognosis of gastric adenocarcinoma patients: A retrospective cohort study

Capillary invasion (CI) has been found to play an important role in metastasis and recurrence of gastric adenocarcinoma (GAC). However, the prognostic significance of CI is still controversial. From January 2005 to December 2011, 1398 patients with GAC who underwent gastrectomy were retrospectively enrolled and divided into CI (+) and CI (−) groups. Clinicopathological features and survival outcomes were compared between these groups. In our study, 227 (16.2%) patients were CI (+). Patients with CI (+) had significantly more advanced tumors and worse prognosis than those with CI (−) (p < 0.001). CI was demonstrated as an independent prognostic factor (p = 0.023) in patients with GAC. When stratified by TNM stage, the prognosis of CI (+) group in stage III was remarkably worse than CI (−) group (p = 0.006), while the differences were not significant in stage I–II and stage IV (both p > 0.05). The nomograms indicated that CI was part of the individual prognostic prediction system. The predictive accuracy of CI and other characteristics was better than TNM alone (p < 0.001). Our finding suggested that CI was an independent prognostic factor in patients with GAC, and the nomogram based on CI and other clinicopathological factors was a valuable and accurate tool in individual prognostic prediction.

Inflammation-based indexes and clinicopathologic features are strong predictive values of preoperative circulating tumor cell detection in gastric cancer patients

PURPOSE

Circulating tumor cell (CTC) count and the host inflammatory response are two independent predictors for patients with various malignant disease. Several inflammation-based indicators have been demonstrated to have prognostic value in many malignant solid tumors, including systemic immune-inflammation index (SII), neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), and prognostic nutrition index (PNI). The aim of this study was to evaluate the predictive value of the inflammation-based indexes including SII, NLR PLR, and PNI for CTC detection of gastric cancer patients before surgery.

METHODS

CTCs were measured using the isolation method by size of epithelial tumor cells and Wright staining for 60 patients with gastric cancer who underwent surgery. The indicators of SII, NLR, PLR, and PNI were calculated based on clinical laboratory testing.

RESULTS

The detected CTC number was correlated with extension of tumor invasion (p = 0.037), lymph node metastasis (p < 0.001), and TNM stage (p < 0.001). The CTC detection ratio was significantly correlated with T stage (p = 0.041), lymph node metastasis (p = 0.001), nerve fiber invasion of tumor outside the lymph nodes (p = 0.017), and TNM stage (p < 0.001). Statistical analysis showed that SII (p < 0.001), NLR (p < 0.001), PLR (p < 0.001), and PNI (p < 0.001) were significantly associated with positive CTC count and CTC detection rate.

CONCLUSIONS

This study provides evidence that preoperative indicators consisting of SII, NLR, PLR, and PNI are robust predictors for CTC detection in gastric cancer patients undergoing tumor resection.

Excellent Long-Term Prognosis and Favorable Postoperative Nutritional Status After Laparoscopic Pylorus-Preserving Gastrectomy

BACKGROUND

Laparoscopic pylorus-preserving gastrectomy (LPPG) has been introduced as a minimally invasive function-preserving operation for early gastric cancer (GC). This study aimed to investigate the surgical and prognostic outcomes after LPPG at the authors' institution.

METHODS

This study analyzed 465 patients who underwent LPPG for cT1 N0 GC located in the middle part of the stomach between 2006 and 2012. Short- and long-term surgical outcomes including 5-year survival rates, postoperative nutritional data, and body weight change were retrospectively investigated.

RESULTS

Regarding short-term surgical results, 14 (3%) of the 465 patients had severe complications classified as Clavien-Dindo grade 3a or above, and no mortality occurred (no in-hospital deaths). The median follow-up period was 1829 days (range 226-3197 days), and the 5-year overall survival and relapse-free survival rates were respectively 98% (95% confidence interval [CI] 96.1-99.0%) and 98% (95% CI 96.1-99.0%). Only two cases of postoperative recurrence were confirmed, and their recurrence sites were not in the remnant stomach or regional lymph nodes. The postoperative nutritional status, in terms of serum total protein, albumin, and hemoglobin levels, was well maintained, and the mean relative body weight (postoperative/preoperative) was 93.24 ± 7.29% after LPPG.

CONCLUSIONS

For the first time, we have clarified the detailed long-term survival outcomes of LPPG for cT1 N0 GC. LPPG is an acceptable and favorable operative method for clinically diagnosed early-stage GC, in terms of long-term survival and postoperative nutrition.

Extensive regeneration of the stomach using bioabsorbable polymer sheets

BACKGROUND

The growing prevalence of endoscopic surgery in recent years has led to the minimization of postoperative scarring. However, this procedure does not allow for the regeneration of the resected digestive tract, which compromises the postoperative maintenance of digestive function. In this preliminary study, we developed an artificial gastric wall (AGW) using bioabsorbable polymer (BAP), and evaluated the ability of this BAP patch to repair and regenerate a widely defective gastric wall in an animal model.

METHODS

Pigs were laparotomized under general anesthesia. An 8 × 8-cm, round portion of the anterior gastric wall was excised and replaced by an AGW. The AGW was composed of a copolymer comprising 50% lactic acid and 50% caprolactone. The animals were relaparotomized 4, 8, or 12 weeks after implantation, after which they underwent resection of the entire stomach for gross and histologic evaluation of the graft sites.

RESULTS

All recipient pigs survived until killing. By 4-8 weeks, the graft site revealed progressively fewer mucosal defect after each day. Moreover, the grafted area was indistinguishable from the native stomach 12 weeks after AGW implantation. The structures of the regenerated mucous membrane and muscle layers were identical to those of the native stomach. Furthermore, proton pumps were found in the regenerated tissue.

CONCLUSION

The BAP sheets helped to restore extensive gastric defects without causing any deformation. The use of BAP sheets may become a new therapeutic method that prevents alterations of gastric volume after extensive gastrectomy for stomach cancer and other diseases.

Long term follow up and retrospective study on 533 gastric cancer cases

Background

Gastric cancer (GC) is the third leading cause of cancer death in China and the outcome of GC patients is poor. The aim of the research is to study the prognostic factors of gastric cancer patients who had curative intent or palliative resection, completed clinical database and follow-up.

Methods

This retrospective study analyzed 533 GC patients from three tertiary referral teaching hospitals from January 2004 to December 2010 who had curative intent or palliative resection, complete clinical database and follow-up information. The GC-specific overall survival (OS) status was determined by the Kaplan-Meier method, and univariate analysis was conducted to identify possible factors for survival. Multivariate analysis using the Cox proportional hazard model and a forward regression procedure was conducted to define independent prognostic factors.

Results

By the last follow-up, the median follow-up time of 533 GC patients was 38.6 mo (range 6.9-100.9 mo), and the median GC-specific OS was 25.3 mo (95% CI: 23.1-27.4 mo). The estimated 1-, 2-, 3- and 5-year GC-specific OS rates were 78.4%, 61.4%, 53.3% and 48.4%, respectively. Univariate analysis identified the following prognostic factors: hospital, age, gender, cancer site, surgery type, resection type, other organ resection, HIPEC, LN status, tumor invasion, distant metastases, TNM stage, postoperative SAE, systemic chemotherapy and IP chemotherapy. In multivariate analysis, seven factors were identified as independent prognostic factors for long term survival, including resection type, HIPEC, LN status, tumor invasion, distant metastases, postoperative SAE and systemic chemotherapy.

Conclusions

Resection type, HIPEC, postoperative SAE and systemic chemotherapy are four independent prognostic factors that could be intervened for GC patients for improving survival.

Synthesis of CdTe quantum dot-conjugated CC49 and their application for in vitro imaging of gastric adenocarcinoma cells

The purpose of this experiment was to investigate the visible imaging of gastric adenocarcinoma cells in vitro by targeting tumor-associated glycoprotein 72 (TAG-72) with near-infrared quantum dots (QDs). QDs with an emission wavelength of about 550 to 780 nm were conjugated to CC49 monoclonal antibodies against TAG-72, resulting in a probe named as CC49-QDs. A gastric adenocarcinoma cell line (MGC80-3) expressing high levels of TAG-72 was cultured for fluorescence imaging, and a gastric epithelial cell line (GES-1) was used for the negative control group. Transmission electron microscopy indicated that the average diameter of CC49-QDs was 0.2 nm higher compared with that of the primary QDs. Also, fluorescence spectrum analysis indicated that the CC49-QDs did not have different optical properties compared to the primary QDs. Immunohistochemical examination and in vitro fluorescence imaging of the tumors showed that the CC49-QDs probe could bind TAG-72 expressed on MGC80-3 cells.

Role of preoperative colonoscopy in patients with gastric cancer: a case control study of the prevalence of coexisting colorectal neoplasms

BACKGROUND

We evaluated the prevalence of coexisting asymptomatic colorectal neoplasm (CRN) in patients with gastric cancer (GC).

METHODS

Preoperative colonoscopic examinations were performed in 495 patients with GC who underwent gastrectomy between January 2009 and December 2010. To compare the prevalence of CRN in these patients with that in a normal population, we selected 495 sex- and age-matched persons who underwent colonoscopies for health screening. Risk factors for CRN were evaluated by univariate and multivariate analyses.

RESULTS

The overall incidence of CRN was 41.8 % (414/990). The prevalence of overall CRN, high-risk CRN, and colorectal carcinoma (CRC) were significantly higher in the GC group than in the control group (overall CRN: 48.9 % vs. 34.7 %; high-risk CRN: 28.3 % vs. 13.5 %; CRC: 2.6 % vs. 0.2 %; all P < 0.001). The presence of GC [odds ratio (OR), 1.82; 95 % confidence interval (CI), 1.4-2.38; P < 0.001], age ≥50 years (OR, 2.58; 95 % CI, 1.75-3.81; P < 0.001), and male sex (OR, 2.28; 95 % CI, 1.72-3.02; P < 0.001) were risk factors for overall CRN. In patients with GC, age ≥40 years (OR, 3.22; 95 % CI, 1.24-8.37; P = 0.016) and male sex (OR, 3.21; 95 % CI, 2.17-4.76; P < 0.001) were risk factors for overall CRN.

CONCLUSIONS

The prevalence of coexisting CRN, including CRC, was higher in patients with GC than in the normal population. Preoperative colonoscopy is strongly indicated in patients with GC who are male and/or ≥40 years of age.

Impact of lymphatic and/or blood vessel invasion in stage II gastric cancer

AIM: To determine the prognostic value of lymphatic and/or blood vessel invasion (LBVI) in patients with stage II gastric cancer.

METHODS: From January 2001 to December 2006, 487 patients with histologically confirmed primary gastric adenocarcinoma were diagnosed with stage II gastric cancer according to the new 7th edition American Joint Committee on Cancer stage classification at the Department of Gastric Cancer and Soft Tissue Surgery, Fudan University Shanghai Cancer Center. All patients underwent curative gastrectomy with standard lymph node (LN) dissection. Fifty-one patients who died in the postoperative period, due to various complications or other conditions, were excluded. Clinicopathological findings and clinical outcomes were analyzed. Patients were subdivided into four groups according to the status of LBVI and LN metastases. These four patient groups were characterized with regard to age, sex, tumor site, pT category, tumor grading and surgical procedure (subtotal resection vs total resection), and compared for 5-year overall survival by univariate and multivariate analysis.

RESULTS: The study was composed of 320 men and 116 women aged 58.9 ± 11.5 years (range: 23-88 years). The 5-year overall survival rates were 50.7% and the median survival time was 62 mo. Stage IIa cancer was observed in 334 patients, including 268 T3N0, 63 T2N1, and three T1N2, and stage IIb was observed in 102 patients, including 49 patients T3N1, 51 T2N2, one T1N3, and one T4aN0. The incidence of LBVI was 28.0% in stage II gastric cancer with 19.0% (51/269) and 42.5% (71/167) in LN-negative and LN-positive patients, respectively. In 218 patients (50.0%), there was neither a histopathologically detectable LBVI nor LN metastases (LBVI⁻/LN⁻, group I); in 51 patients (11.7%), LBVI with no evidence of LN metastases was detected (LBVI⁺/LN⁻, group II). In 167 patients (38.3%), LN metastases were found. Among those patients, LBVI was not determined in 96 patients (22.0%) (LBVI⁻/LN⁺, group III), and was determined in 71 patients (16.3%) (LBVI⁺/LN⁺, group IV). Correlation analysis showed that N category and the number of positive LNs were significantly associated with the presence of LBVI (P < 0.001). The overall 5-year survival was significantly longer in LN-negative patients compared with LN-positive patients (56.1% vs 42.3%, P = 0.015). There was a significant difference in the overall 5-year survival between LBVI-positive and LBVI-negative tumors (39.6% vs 54.8%, P = 0.006). Overall 5-year survival rates in each group were 58.8% (I), 45.8% (II), 45.7% (III) and 36.9% (IV), and there was a significant difference in overall survival between the four groups (P = 0.009). Multivariate analysis in stage II gastric cancer patients revealed that LBVI independently affected patient prognosis in LN-negative patients (P = 0.018) but not in LN-positive patients (P = 0.508).

CONCLUSION: In LN-negative stage II gastric cancer patients, LBVI is an additional independent prognostic marker, and may provide useful information to identify patients with poorer prognosis.

Comparative study of complete and partial omentectomy in radical subtotal gastrectomy for early gastric cancer

PURPOSE

Curative surgery for patients with advanced or even early gastric cancer can be defined as resection of the stomach and dissection of the first and second level lymph nodes, including the greater omentum. The aim of this study was to evaluate the short- and long- term outcomes of partial omentectomy (PO) as compared with complete omentectomy (CO).

MATERIALS AND METHODS

Seventeen consecutive open distal gastrectomies with POs were initially performed between February and July in 2006. The patients' clinicopathologic data and post-operative outcomes were retrospectively compared with 20 patients who underwent open distal gastrectomies with COs for early gastric cancer in 2005.

RESULTS

The operation time in PO group was significantly shorter than that in CO group (142.4 minutes vs. 165.0 minutes, p=0.018). The serum albumin concentration on the first post-operative day in PO group was significantly higher than CO group (3.8 g/dL vs. 3.5 g/dL, p=0.018). Three postoperative minor complications were successfully managed with conservative treatment. Median follow-up period between PO and CO was 38.1 and 37.7 months. All patients were alive without recurrence until December 30, 2009.

CONCLUSION

PO during open radical distal gastrectomy can be considered a more useful procedure than CO for treating early gastric cancer. To document the long-term technical and oncologic safety of this procedure, a large-scale prospective randomized trial will be needed.

Log-normal censored regression model detecting prognostic factors in gastric cancer: A study of 3018 cases

AIM: To investigate the efficiency of Cox proportional hazard model in detecting prognostic factors for gastric cancer.

METHODS: We used the log-normal regression model to evaluate prognostic factors in gastric cancer and compared it with the Cox model. Three thousand and eighteen gastric cancer patients who received a gastrectomy between 1980 and 2004 were retrospectively evaluated. Clinic-pathological factors were included in a log-normal model as well as Cox model. The akaike information criterion (AIC) was employed to compare the efficiency of both models. Univariate analysis indicated that age at diagnosis, past history, cancer location, distant metastasis status, surgical curative degree, combined other organ resection, Borrmann type, Lauren’s classification, pT stage, total dissected nodes and pN stage were prognostic factors in both log-normal and Cox models.

RESULTS: In the final multivariate model, age at diagnosis, past history, surgical curative degree, Borrmann type, Lauren’s classification, pT stage, and pN stage were significant prognostic factors in both log-normal and Cox models. However, cancer location, distant metastasis status, and histology types were found to be significant prognostic factors in log-normal results alone. According to AIC, the log-normal model performed better than the Cox proportional hazard model (AIC value: 2534.72 vs 1693.56).

CONCLUSION: It is suggested that the log-normal regression model can be a useful statistical model to evaluate prognostic factors instead of the Cox proportional hazard model.

Early signet ring cell gastric cancer

BACKGROUND

Signet ring cell carcinoma (SRC) is defined as a histological entity. The clinicopathological characteristics and prognosis of gastric SRC remain controversial.

METHODS

From 1994 to 2006, 2,439 patients with gastric carcinoma who underwent gastrectomy were enrolled. Of these, 505 patients (20.7%) had SRC and were compared to 1,934 patients with other histological types.

RESULTS

Twenty-nine percent of patients in the SRC group (n = 149) had early gastric cancer, with tumor invasion limited to the mucosa or submucosa, compared to 22.2% of patients in the non-SRC group (n = 430). The proportion of regional LN metastases was 10.7 and 16.0% in early SRC and early non-SRC, respectively, (p = 0.115). The 5-year survival rates for patients with early SRC were better than those for patients with early non-SRC (96.1 vs. 89.6%, p = 0.01).

CONCLUSIONS

Early gastric SRC has favorable prognosis. There is no significant difference in terms of LN metastasis between SRC histologic type and other histological types. Less-invasive strategies may be acceptable in selected patients with early gastric SRC.

Human leukocyte antigen-G is closely associated with tumor immune escape in gastric cancer by increasing local regulatory T cells

Human leukocyte antigen-G (HLA-G) plays an important role in tumor cell escape. We investigated HLA-G expression and regulatory T cells (Tregs) infiltrates in patients with gastric cancer (GC), analyzed their relationship with clinicopathologic features, and characterized their role in tumor immune escape. We also investigated the plasma soluble HLA-G level and its potential in the diagnosis of GC. Effect of HLA-G on Tregs was further assessed by coculture experiments in vitro. Most interestingly, HLA-G positive expression was detected in GC tissues and it was significantly correlated with the presence of tumor-infiltrating Tregs. Patients with HLA-G positive expression or high Tregs had significantly poorer survival at 5 years after operation. Multivariate analysis indicated that HLA-G positive expression was an independent prognostic factor of GC. The coculture experiment showed overexpression of HLA-G in GC cell lines significantly enhanced the frequency of Tregs when GC cells were directly cocultured with human peripheral blood mononuclear cell. However, this effect disappeared when the indirect coculture system was applied. Some cytokines such as interleukin-6, interleukin-10, and tumor necrosis factor-α significantly changed in the coculture system. Moreover, plasma soluble HLA-G level in GC patients was higher than that in normal controls. Taken together, our results indicated that HLA-G expression was closely associated with tumor progression and involved in tumor evasion by increasing the frequency of infiltrating Tregs locally. Thus, HLA-G might be a promising predictor for disease prognosis and a possible novel target for immunotherapy in GC patients.

Long-term outcomes and survival after laparoscopy-assisted distal gastrectomy for gastric cancer: three-year survival analysis of a single-center experience in Korea

BACKGROUND AND OBJECTIVES

Laparoscopy-assisted distal gastrectomy (LADG) has been established as an alternative treatment for early gastric cancer (EGC) because of excellent short-term results. However, only a few reports have considered the long-term outcomes of LADG. In this study, we investigated the 3-year outcome and survival of patients who underwent LADG.

METHODS

We assessed 182 patients with gastric adenocarcinoma who underwent LADG. The indication for LADG was confined to EGCs (T1N0 or T1N1 cases). The clinicopathological characteristics and long-term survival data of all patients were analyzed.

RESULTS

The overall morbidity and mortality rates of the patients were 11% and 0%, respectively. An analysis of the final pathological stages of the patients revealed that 160 had stage Ia, 20 had stage Ib, and only 2 had stage II. The median follow-up period was 44 months (range, 2-73 months), and there were two recurrences. Five patients died of other causes, but no patients died of a gastric cancer recurrence. The 3-year overall and disease-specific survival rates were 97.3% and 100%, respectively.

CONCLUSIONS

LADG for EGC is acceptable in terms of both short- and long-term outcomes. Thus, LADG can be considered a primary treatment for EGC.

Assessment of quality of life after gastrectomy using EORTC QLQ-C30 and STO22

BACKGROUND

The European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Cancer (QLQ-C30) and the site-specific module for gastric cancer (QLQ-STO22) have seldom been used to measure the postoperative health-related quality of life (HRQOL) in Japanese gastric cancer patients. The aim of this study was to evaluate the HRQOL after gastrectomy using these instruments and to compare various aspects of HRQOL among surgical procedures.

METHODS

A total of 98 patients who underwent gastrectomy and had no recurrence were evaluated. Among them, we compared the differences between major surgical procedures consisting of open total gastrectomy (TG, n=8), open distal gastrectomy (DG, n=24), and laparoscopy-assisted distal gastrectomy (LADG, n=44). Questionnaires were completed at baseline and at 1, 3, 6 and 12 months postoperatively.

RESULTS

The worst scores for most of the items were observed at 1 month after surgery and usually improved thereafter. Scores after TG were the worst of all surgical procedures across all dimensions throughout the period. Scores after LADG were generally superior to those after DG at 1 and 3 months postoperatively but not at 12 months.

CONCLUSIONS

EORTC QLQ-C30 and STO22 detected differences in several aspects of HRQOL among patients treated by the three surgical procedures. The laparoscopic approach resulted in superior short-term outcomes, whereas TG continued to affect the HRQOL in several items 12 months after surgery.

Prognostic significance of perineural invasion in patients with gastric cancer who underwent curative resection

BACKGROUND

The prognostic significance of perineural invasion (PNI) in gastric cancer has been previously investigated in a few studies, but had not reached a consensus. The aim of this study was to determine the prognostic value of PNI in patients with gastric cancer who underwent curative resection.

MATERIALS AND METHODS

We retrospectively analyzed 238 patients who had undergone curative gastrectomy. Paraffin sections of surgical specimens from all patients were stained with hematoxylin and eosin. PNI was defined when carcinoma cells infiltrated into the perineurium or neural fascicles. PNI and the other prognostic factors were evaluated by univariate and multivariate analysis.

RESULTS

PNI was detected as positive in 180 of the 238 patients (75.6%). pT stage, tumor size, lymph node metastasis, clinical stage, tumor differentiation, Borrmann classification, histological type, lymphatic vessel invasion, and blood vessel invasion were closely associated with the presence of PNI. The PNI-positive tumors had significantly larger size and more lymph node metastasis than the PNI-negative tumors (P = .001 and P < .001, respectively). The median survival of the PNI-positive patients was significantly worse than that of the PNI-negative patients (28.1 vs. 64.9 months, P = .001). Multivariate analysis indicated that the positivity of PNI was an independent prognostic factor (P = .02, hazard ratio [HR]: 2.75; 95% confidence interval [95% CI]:1.12-3.13) as were classical clinicopathological features.

CONCLUSION

Our results showed that the frequency of PNI was high in patients with gastric cancer who underwent curative gastrectomy and the proportion of PNI positivity increased with progression and clinical stage of disease. PNI may be useful in detecting patients who had poor prognosis after curative resection in gastric cancer.

Accuracy of surgical diagnosis in detecting early gastric cancer and lymph node metastasis and its role in determining limited surgery

BACKGROUND

The aim of this study was to evaluate the accuracy of surgical diagnosis of early gastric cancer (EGC) and lymph node metastasis, and elucidate its role in determining limited surgery for EGC.

STUDY DESIGN

We reviewed 369 patients undergoing gastrectomy for primary gastric carcinoma. Surgical diagnosis was evaluated by determining its sensitivity, specificity, and accuracy, and was compared with preoperative examinations.

RESULTS

Sensitivity, specificity, and accuracy of intraoperative diagnosis for EGC were 74.5%, 95.7%, and 83.7%, respectively. The predictive value for EGC by intraoperative diagnosis was 95.7%. Surgical diagnosis of EGC showed higher specificity and predictive value than preoperative examinations did, which significantly reduced the risk of underestimating advanced gastric cancer (AGC) to EGC. The sensitivity, specificity, and accuracy for lymph node metastasis by surgical diagnosis were 73.2%, 78.1%, and 76.4%, respectively. In 70 patients with a discrepancy in the diagnosis of EGC between pre- and intraoperative diagnoses, surgical diagnosis was correct in 63 (90%) patients, but preoperative examination was correct in only 7 (10%) patients.

CONCLUSIONS

Surgical diagnosis shows better accuracy than preoperative examinations do in detecting EGC and lymph node metastasis. Our results suggest that the decision to perform limited surgery based on surgical diagnosis might reduce the risk of undertreatment of AGC to EGC better than preoperative examinations.

Robot-assisted gastrectomy with lymph node dissection for gastric cancer: lessons learned from an initial 100 consecutive procedures

OBJECTIVE

To evaluate the technical feasibility, effectiveness, and safety of robot-assisted gastrectomy (RAG) with lymphadenectomy, using the da Vinci system through analyses of our initial series of 100 consecutive patients.

SUMMARY BACKGROUND DATA

The application of robotic surgery was proven to be one of the best cutting-edge technologies for successful minimally invasive surgery by providing solutions to the many drawbacks of laparoscopic surgery, yet few reports have studied robotic surgery in gastric cancer.

METHODS

A review of a prospectively designed database at our institute from July 2005 to October 2007 revealed a series of 100 consecutive RAG patients with a preoperative diagnosis of early gastric cancer. Clinicopathologic characteristics and surgical outcomes were analyzed.

RESULTS

All operations were performed successfully without open or laparoscopic conversion. There were 33 total gastrectomies and 67 subtotal gastrectomies with D1+beta or extended lymphadenectomy (D2). The mean total operation time and console time were 231 and 150 minutes, respectively. There were 13 postoperative morbidities and 1 postoperative mortality. The first flatus was noted on postoperative day 2.9, soft diet was started on postoperative day 4.2, and the mean postoperative hospital stay was 7.8 days. Although all patients were diagnosed as early gastric cancer preoperatively, the final pathology report revealed that 19 patients exhibited a depth deeper than T2. The mean number of retrieved lymph nodes was 36.7 (range, 11-83). None of the specimens showed microscopic tumor involvement in the resection line.

CONCLUSIONS

This study demonstrated that RAG with lymphadenectomy can be applied safely and effectively for patients with gastric cancer.

Laparoscopy-assisted distal gastrectomy for overweight patients in the Asian population

PURPOSE

It is generally considered difficult to operate on overweight patients, who are also at increased risk of postoperative complications. We conducted this study to clarify the technical feasibility and postoperative outcomes of laparoscopy-assisted distal gastrectomy (LADG) for early gastric cancer (EGC) in overweight patients.

METHODS

Between July 2004 and December 2006, 116 patients with preoperatively diagnosed EGC underwent LADG at our department. We classified these patients into two groups based on body mass index (BMI). There were 60 patients in the high-BMI (> or =23 kg/m2) group and 56 in the low-BMI (<23 kg/m2) group. The clinicopathologic features, postoperative outcomes, and operation-related morbidities were compared.

RESULTS

None of the patients needed conversion to laparotomy. There were no notable differences in clinical characteristics or histologic features between the groups. Although the operation time was significantly longer in the high-BMI group, there were no significant differences in postoperative bowel recovery, postoperative hospital stay, or operation-related morbidities.

CONCLUSIONS

Laparoscopy-assisted distal gastrectomy for overweight patients is feasible and safe; however, because of its technical difficulties and the complexities of lymph node dissection, it should be carefully considered, and may only be suitable for early-stage cancers.

Omentum-preserving gastrectomy for early gastric cancer

BACKGROUND

The omentum has variable functions in surgical procedures. Nevertheless, there is very little information about the effect of omentum on abdominal complications after gastrectomy. The purpose of the present study was to determine the outcome of omentum-preserving gastrectomy for early gastric cancer.

METHODS

We evaluated 1,116 patients who had a gastrectomy for early gastric cancer between the years 2004 and 2006; 992 patients underwent conventional gastrectomy (CG), and 124 patients had an omentum-preserving gastrectomy (OPG). These cases were analyzed retrospectively. The early and late abdominal complications were compared between the CG and OPG groups.

RESULTS

The results of the study show no significant differences between the early abdominal complications in the CG and OPG groups. However, the late abdominal complication rate in the OPG was significantly lower than the CG (p = 0.026). The most common risk factor associated with early abdominal complications was type of operation. The combination of CG and early abdominal complication represented a statistically significant risk for late abdominal complications (p = 0.026, 0.031 respectively).

CONCLUSION

The findings of this study demonstrate that the omentum-preserving gastrectomy in the treatment of early gastric cancer showed a lower rate of abdominal complications compared to the conventional gastrectomy.

Prognostic role of lymphatic vessel invasion in early gastric cancer: a retrospective study of 188 cases

BACKGROUND

Lymphatic vessel invasion is an important prognostic factor for the gastric cancer without lymph node metastasis. However, the studies on early gastric cancers is still sparse. Therefore, we carried out this study to determine clinicopathological and surgical prognostic factors, especially lymphatic vessel invasion, for early gastric cancers.

METHODS

Clinicopathological characteristics and prognostic outcomes of 188 patients who received a gastrectomy for early gastric cancer between 1980 and 2000 were retrospectively evaluated based on the subclassification of pN category. A multivariate analysis was performed by using the Cox regression model, where lymphatic vessel invasion and other potential prognostic factors were included.

RESULTS

Of the 188 patients, 158 had T1N0M0 and 30 T1N1M0 cancers. In patients with T1N0M0 cancers, the survival rate was significantly lower in those with lymphatic vessel invasion than in those without (chi(2)=4.025, P=0.045). However, in patients with T1N1M0 cancers, the survival rates were not significantly different between those with and those without lymphatic vessel invasion (chi(2)=0.253, P=0.615). The multivariate analysis identified that age (P=0.033) and lymph node metastasis (P=0.019) were independent prognostic factors for all early gastric cancers. However, age (P=0.042), tumor location (P=0.032), and lymphatic vessel invasion (P=0.010) were the independent prognostic factors for T1N0M0 cancers.

CONCLUSIONS

Lymphatic vessel invasion was an independent prognostic factor for T1N0M0 early gastric cancers, and thus may be a potential prominent factor that should be considered to be included in the category of lymphoid metastasis (both lymph node metastasis and lymphatic vessel invasion) in patients with early gastric cancer.

Validation of staging systems for gastric cancer

BACKGROUND

The two major staging systems for gastric cancer, the Japanese classification of gastric cancer (JCGC) and the International Union Against Cancer (UICC) TNM system, are periodically revised as a consequence of critical validation studies in light of newly accumulated clinical data. This study aimed to validate and improve upon the current versions for a better prognostic stratification of gastric cancer.

METHODS

One thousand and ten gastric cancer patients who underwent tumor resection were enrolled at the Kitasato University Hospital for staging validation. According to the JCGC stage, the patients consisted of stage IA (n=453), IB (n=185), II (n = 119), IIIA (n=75), IIIB (n=51), and IV (n=127).

RESULTS

Regarding consistency between the JCGC and the UICC system, the results were: for patients in stage IA (100%), IB (98%), II (84%), IIIA (51%), IIIB (24%), and IV (64%). The JCGC system was superior to the UICC system for the prognostic stratification of stage IIIA, IIIB, and IV cancers; we therefore used the JCGC system for prognostic validation according to depth of invasion in cancers of the same stage. Stage II and IIIA cancers were heterogeneous for prognosis according to depth of invasion, and the outstanding difference was found between the muscularis propria (MP) and subserosa (SS), which are both classified as pT2 in the JCGC system. MP cancer represented an earlier property of gastric cancer rather than an advanced one. A proposed novel staging system adjusted for this heterogeneity provided a clearer stratification of prognosis with a homogeneous prognostic distribution within each stage.

CONCLUSION

Our findings revealed that invasion into the MP has an earlier propensity than expected, and a novel staging system taking this into account may provide a better stratification of prognosis than the current systems.

Laparoscopy-assisted distal gastrectomy for gastric cancer

OBJECTIVE

The purpose of this study was to evaluate the safety and value of laparoscopy-assisted distal gastrectomy (LADG) for early stage gastric cancer (stages IA, IB, and II).

MATERIALS AND METHODS

We retrospectively assessed 101 cases treated by LADG and compared to 49 contemporaneous cases treated by open distal gastrectomy (DG) between 2001 and 2006. Clinical variables, such as tumor diameter, operation time, blood loss, number of lymph nodes dissected, and length of stay were investigated.

RESULTS

Tumor size (mm) was significantly smaller in the LADG group (p < 0.0001). Although operation time (min) in the two groups was similar (278 +/- 57 vs. 268 +/- 55), mean blood loss was significantly higher in the DG group (139 +/- 181 vs. 460 +/- 301, p < 0.0001). Fewer lymph nodes were harvested in the LADG group (27 +/- 14 vs. 34 +/- 19, p = 0.012). Hospital stay was longer in the DG group (13.3 +/- 8.5 vs. 16.7 +/- 10.5, p = 0.034). There was no mortality in either group. Postoperative surgical complications occurred in six (6%) of the LADG and four (8%) of the DG.

CONCLUSIONS

The authors conclude that laparoscopy-assisted distal gastrectomy is a safe and useful operation for early-stage gastric cancers. If patients are selected properly, laparoscopy-assisted distal gastrectomy can be a curative and minimally invasive treatment for gastric cancer.

Laparoscopic local resection based on sentinel node evaluation for early gastric cancer: a preliminary report

We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric cancer.

Indication for endoscopic mucosal resection in early signet ring cell gastric cancer

BACKGROUND

The aim of this study was to compare the clinicopathological characteristics of an early signet ring cell carcinoma (SRC) with an early undifferentiated carcinoma (mucinous, poorly differentiated adenocarcinoma) and early differentiated carcinoma (well or moderately differentiated tubular adenocarcinoma, papillary adenocarcinoma) and find indications for endoscopic mucosal resection (EMR) in early SRC.

METHODS

1520 patients with early gastric cancer (EGC), who underwent a curative gastrectomy, were analyzed retrospectively. Among them, 388 patients with SRC were compared with 253 patients with undifferentiated carcinoma (UDC) and 879 with a differentiated carcinoma (DC).

RESULTS

SRC was more common in young female patients than UDC. SRC had a tendency to be confined to the mucosa, with smaller size than UDC. The lymph node metastasis rate for SRC was lower than that for UDC, but similar to that of DC. Multivariate analysis revealed lymph node metastasis (LNM) to be associated with the depth of invasion, tumor size, histological type, and lymphatic involvement. SRC had no LNM in the case of a mucosal tumor, smaller than 2 cm, and in the absence of lymphatic involvement. The prognosis of SRC was more favorable than UDC.

CONCLUSIONS

Early SRC has different characteristics from early UDC. In view of the lower rate of lymph node metastasis and better prognosis, we suggest that EMR can be performed on patients with early SRC limited to the mucosa, less than 2cm in size, and with no lymphatic involvement.

Longterm outcomes of early-stage gastric carcinoma patients treated with laparoscopy-assisted surgery

BACKGROUND

Laparoscopy-assisted approaches have become popular for dissecting early-stage gastric cancer in Japan, but the outcomes after 5 years of followup have not been reported.

STUDY DESIGN

Between January 1998 and March 2002, 94 patients with histologically proved early-stage gastric carcinoma participated in clinical studies and underwent gastrectomy with regional lymphadenectomy to evaluate feasibility and safety of the laparoscopy-assisted approach. Outcomes and pattern of disease failure during followup up to 5 years were evaluated in all patients. Multivariable analysis was performed to identify relevant prognostic factors.

RESULTS

Conversion to open procedures occurred in three patients. Median blood loss was 90 mL (interquartile range, 160 mL), and duration of operation was 230 minutes (interquartile range, 60 minutes). Operative morbidity and mortality were 22.3% and 0%, respectively. Nine patients died during the course of followup, for an overall 5-year survival rate of 90%. Two patients died of recurrent disease, and 2 other patients have been diagnosed with recurrences, for a 5-year recurrence-free survival of 95.6%. Three patients with recurrent cancer, including 1 with port-site recurrence, had stage IA disease (pT1pN0) at operation. Diabetes mellitus as a comorbidity was prominent as a prognostic factor.

CONCLUSIONS

Outcomes of patients with a preoperative diagnosis of early-stage cancer were excellent when treated with a laparoscopy-assisted approach, although rare patterns of disease failure were observed.

Lymph node involvement in gastric cancer for different tumor sites and T stage: Italian Research Group for Gastric Cancer (IRGGC) experience

BACKGROUND

The aim of lymphadenectomy is to clear all the metastatic nodes achieving a complete removal of the tumor; nevertheless, its role in gastric cancer has been very much debated.

MATERIALS AND METHODS

The frequency of node metastasis in each lymphatic station according to the International Gastric Cancer Association, was studied in 545 patients who underwent D2 or D3 lymphadenectomy from June 1988 to December 2002.

RESULTS

Upper third early cancers have shown an involvement of N2 celiac nodes in 25%. In advanced cancers, there was a high frequency of metastasis in the right gastroepiploic (from 10% in T2 to 50% in T4) and in the paraaortic nodes (26% in T2, 32% in T3, 38 % in T4). N3 left paracardial nodes involvement was observed in an important share of middle third tumors (17% in T3, 36% in T4). Splenic hilum nodes metastasis were common in T3 and T4 cancers located in the upper (39%) and middle (17%) stomach. N2 nodal involvement was frequent in lower third advanced cancers. Metastasis in M left paracardial and short gastric nodes were observed in a small percentage of cases.

CONCLUSION

Given the nodal diffusion in our gastric cancer patients, extended lymphadenectomy is still a rationale to obtain radical resection.

Outcome of segmental gastrectomy versus distal gastrectomy for early gastric cancer

BACKGROUND

Because of the frequent occurrence of postgastrectomy disturbances after distal gastrectomy (DG), segmental gastrectomy (SG) has recently been applied to early gastric cancer (EGC). Outcomes of SG and DG in patients with EGC were compared to clarify the usefulness of SG as a treatment for EGC.

METHODS

This retrospective study involved 61 patients with EGC: 28 patients who underwent DG before March 1996 and 33 patients who underwent SG after April 1996 during the period April 1991 through March 2002. Patient and tumor characteristics, operative results, and postoperative outcomes were compared between the two groups.

RESULTS

The postoperative/preoperative body weight ratio was higher in the SG group than in the DG group. Early dumping syndrome and reflux gastritis occurred less frequently after SG than after DG. The incidence of postoperative complications was similar in the two groups. All patients remained alive without recurrence during a mean follow-up period of 54.7 months in the SG group and 99.9 months in the DG group.

CONCLUSIONS

In comparison to DG, SG is associated with improved postoperative quality of life with no decrease in operative curability of EGC. Thus, SG is a feasible treatment for EGC.

Factors influencing operation time of laparoscopy-assisted distal subtotal gastrectomy: Analysis of consecutive 100 initial cases

AIMS

There is little information on patient selection criteria for laparoscopy-assisted distal gastrectomy (LADG) that would facilitate a successful initial experience for a surgeon new to the procedure. This study aimed to establish patient selection criteria that will allow increased proficiency and shorter operation times for the LADG procedure.

METHOD

One hundred LADG with lymphadenectomy and no other combined procedures were consecutively performed by one surgeon. These 100 consecutive LADG procedures were analyzed retrospectively from a prospectively designed computer database. Uni- and multivariate analyses were performed to identify factors influencing operation time.

RESULTS

According to univariate analysis, operation time was influenced by sex, BMI, surgical experience, and tumor location, whereas multivariate analysis indicated that operation time was significantly influenced only by BMI and surgical experience. The same analyses of only the first 50 cases showed that sex, BMI, surgical experience, and tumor location were independently associated with operation time. As BMI increased, so did operation time, whereas operation time decreased with increasing surgical experience.

CONCLUSION

This study suggests that surgeons who have limited experience with this advanced procedure may shorten operation time by considering patient and tumor characteristics in their early attempts at LADG. With a shortened operation time, surgeon with limited experience may become proficient to LADG rapidly.

Ingestion of difructose anhydride III, a non-digestible disaccharide, improves postgastrectomy osteopenia in rats

OBJECTIVE

Total gastrectomy produces osteopenia with calcium malabsorption. We previously demonstrated that difructose anhydride III (DFAIII), a non-digestible disaccharide, stimulates intestinal calcium absorption in normal and ovariectomized rats. In the present study, we examined the effects of feeding DFAIII on gastrectomy-induced calcium malabsorption and osteopenia in rats. The potential of DFAIII to promote large intestinal calcium absorption was also evaluated through comparison with that of fructooligosaccharides (FOS).

MATERIAL AND METHODS

Male Sprague-Dawley rats were divided into two groups: totally gastrectomized and sham-operated rats. After a postoperative recovery period, rats from each group were divided into three subgroups and fed the control, DFAIII (30 g/kg), or FOS (30 g/kg) diet for 28 days.

RESULTS

Total gastrectomy severely reduced net calcium absorption, femoral calcium content and bone mineral density, resulting in fragility of the femur. DFAIII or FOS feeding partly and similarly restored the lowered calcium absorption and femoral variables, with an increase in the total short-chain fatty acid pool in the cecum. In gastrectomized rats, net calcium absorption was correlated with several cecal parameters, suggesting that cecal fermentation of DFAIII is associated with the improvement in gastrectomy-induced calcium malabsorption. Urinary excretion of deoxypyridinoline (D-Pyr) as a marker of bone resorption was increased by gastrectomy, and the elevated D-Pyr excretion was suppressed by feeding DFAIII.

CONCLUSIONS

Supplemental feeding of DFAIII partly prevents postgastrectomy osteopenia as a result of an improvement in calcium absorption. Our results suggest that the promotive effects of DFAIII on calcium absorption in the large intestine are comparable to those of FOS.

Treating gastric tube cancer with distal gastrectomy preserving the gastroepiploic artery

Total resection of the gastric tube with lymphadenectomy is standard and reliable treatment for gastric tube cancer. However the risk associated with totally removing a gastric tube previously reconstructed through the posterior mediastinal route is significant, given the need to lyse a significant number of adhesions in order to reach the mediastinum. As a less invasive procedure, we used distal gastrectomy to treat superficial gastric tube cancer in 2 patients. The distal gastric tube was mobilized and resected with preservation of the right gastroepiploic artery, and the Roux-en-Y gastrojejunostomy was used for reconstruction. This procedure was curative with less surgical stress.

Perspectives in the treatment of gastric cancer

The overall 5-year survival of patients with gastric cancer is only 23% in the US compared with 60% in Japan. For Western patients, detecting the disease earlier and applying treatment quality control could substantially improve clinical outcome. For the treatment of gastric cancer, complete tumor resection, whenever feasible, is the standard treatment. Resection of the primary tumor (partial or total gastrectomy) is based on standardized criteria of the tumor, such as location, stage, histology, and surgical margins. The extent of regional lymphadenectomy required, however, has been a matter of considerable debate. Emerging evidence from the latest randomized controlled trials show that extended (D2) lymphadenectomy is safe and able to cure 20% of patients with N2-disease compared with 0% treated with limited D1 dissection, provided that the optimal surgical technique is used. Estimates suggest that this N2-specific subgroup advantage reflects a potential absolute overall survival benefit of 3-6%. Postoperative decisions about adjuvant chemotherapy and radiotherapy are based on pathologic staging, the extent of surgery performed (D0/D1 vs D2/D3) and the risk-benefit ratio. Recurrence-risk and mortality-risk reduction is achievable with a carefully planned relapse-prevention guided therapeutic strategy. Patient-related factors (tumor features and expected recurrence-risk magnitude) and treatment-related factors (surgical experience, adjuvant treatment risk-benefit ratio) should be considered on an individual basis. In future, genomic-based approaches will help to provide a more personalized therapeutic approach and improve patient outcome.

A prospective randomized study comparing open vs laparoscopy-assisted distal gastrectomy in early gastric cancer: early results

BACKGROUND

We conducted a prospective randomized trial to compare laparoscopy-assisted distal gastrectomy (LADG) including lymphadenectomy with open distal gastrectomy for the management of early gastric cancer (EGC).

METHODS

Forty-seven patients who had been diagnosed endoscopically with EGC were included in a study that ran from November 2001 to August 2003. With the aid of random number table, 23 patients were assigned to the open group (group O) and 24 patients were assigned to the LADG group (group L).

RESULTS

Estimated blood loss and transfusion amounts were similar in the two groups. The mean postoperative hospital stay and the duration of analgesic administration were shorter for group L but not significantly so. The mean number of harvested lymph nodes was 38.1 in the O group and 31.8 in the L group (p = 0.098). Postoperative pulmonary complications occurred more frequently in the O group (p = 0.043). At a median follow-up of 14 months, there has been no recurrence of disease in either group.

CONCLUSION

In terms of resulting in fewer pulmonary complications while maintaining the curability of EGC, LADG has a clear advantage over its open counterpart.

Review article: Barrett's oesophagus and associated adenocarcinoma--a UK perspective

In the UK and across the Western world there has been a rapid increase in oesophageal adenocarcinoma, such that this cancer is now more common than squamous cell carcinoma. The 5-year mortality from oesophageal adenocarcinoma is >80% and therefore there has been increasing interest in the pre-malignant condition Barrett's oesophagus. Barrett's oesophagus is defined by a visible columnar-lined segment with histopathological evidence of a glandular epithelium, which typically contains intestinal metaplasia. Once Barrett's oesophagus is diagnosed, most centres in the UK offer endoscopic surveillance with the aim to detect early, curable lesions. Surveillance in its current form is cumbersome and expensive, and new endoscopic and molecular developments are hoped to improve the yield of such procedures. The current treatments are symptomatic control of reflux symptoms, with more definitive treatments usually reserved for patients with at least high-grade dysplasia. There is interest in chemoprevention strategies, including proton-pump inhibitors, cyclo-oxygenase-2 inhibitors and aspirin, but to date none of these have proven effective. Treatment options for high-grade dysplasia include surgery, endoscopic mucosal resection (in the context of a visible lesion) and photodynamic therapy. Comparative studies between various geographical regions, as the predominant histopathological subtypes of oesophageal cancer change, may give us some clues about the pathogenesis of Barrett's adenocarcinoma.

Lymph node metastasis as a significant prognostic factor in gastric cancer: a multiple logistic regression analysis

BACKGROUND

In Japan, the standard treatment policy for all potentially curable patients with gastric cancer is radical resection including extensive lymphadenectomy. This treatment strategy has been used for both early and advanced gastric cancers, and substantial increases in survival time have been reported. In advanced gastric cancer, lymphatic spread is reported to be one of the most relevant prognostic factors for gastric cancer resected for cure. The purpose of this study was to determine the factors affecting lymph node involvement and to establish guidelines for the extent of lymph node dissection most appropriate for the treatment of gastric cancer.

METHODS

The clinicopathological features of 926 patients with gastric cancer were reviewed. Information on the clinicopathological features was obtained from the database of gastric cancer at the Department of Gastroenterological Surgery, Sendai National Hospital. Univariate and multivariate analyses of data for patients with gastric cancer tumors were performed to evaluate the prognostic significance of clinicopathological features. The independent risk factors influencing lymph node metastasis were determined by multiple logistic regression analysis.

RESULTS

The following clinicopathologic factors were found to be correlated with prognosis of gastric cancer: (1) macroscopic type, (2) depth of invasion, (3) cancer-stromal relationship, (4) histological growth pattern, (5) lymph node involvement, (6) lymphatic invasion, (7) vascular invasion and (8) tumor site. However, a multivariate analysis revealed that macroscopic type, depth of invasion, lymph node involvement and tumor site are independent risk factors for the prognosis of gastric cancer patients. Among these factors, the prognosis of patients with gastric cancer was most strongly influenced by lymph node involvement (odds ratio, 4.632). According to a multiple logistic regression model, depth of cancer invasion and lymphatic invasion was significantly correlated with lymph node metastases.

CONCLUSIONS

Lymph node involvement has the strongest influence on the prognosis of gastric cancer. Among the clinicopathological factors, depth of invasion and microscopically lymphatic invasion are important factors in predicting lymph node metastases. Thus, the ability to perform gastrectomy with dissection of lymph nodes is a basic requirement for gastric cancer surgeons.