Surgical treatment of advanced gastric cancer: Japanese perspective

Implications of compressive loading of the stomach wall: Interplay between mechanical deformation and microstructure

During gastric surgery, the stomach wall is compressed with clamps and sutures or staple lines. These short- and long-term deformations can severely compromise the integrity of the tissue and make it difficult for the stomach wall to respond and remodel to the new loading conditions. Consequently, serious intra- and postoperative complications such as the formation of leaks during bariatric surgeries, can be associated with these immense tissue deformations. Hence, the study aimed to investigate the effects of compressive loading of the stomach wall in the radial direction. This was done by macroscopic mechanical loading of the stomach wall in each region of the stomach and evaluating the microstructural changes inflicted in the tissue. For this purpose, several imaging techniques were used, i.e., a histological analysis, second-harmonic generation microscopy, and X-ray micro-computed tomography. The combination of these three methods allowed us to investigate the gradual compression of the different stomach layers as well as the local reorientation and deformation of the main microstructural components, e.g., collagen fibers and muscle bundles. Importantly, this study found that the collagen bundles in the stomach wall straighten and reorient toward the circumferential-longitudinal plane and partially fan out with increased radial compressive deformation. The 3D scans of the stomach wall indicated a deterioration of the blood vessels and buckling of the mucosal glands due to compression. Statement of significance Unfortunately, little is known about the load transfer in the stomach wall during gastric surgery and the associated deformations on the macro- and microscale. The present study investigates the structural changes of the stomach wall, its layers and the inherent biological building blocks using histology, multi-photon microscopy, and micro-computed tomography. For the first time, the layer-specific response to stepwise radial compression of the stomach wall was studied, the related collagen fiber parameters were estimated, and a 3D sample structure was visualized. This clinically-oriented study links the structural changes within the wall to the postoperative remodel- ing process and the irreversibly altered gastric motility, thereby underscoring its relevance to the field of biomedical engineering, e.g., the development and improvement of surgical instruments.

Development of a reliable surgical quality assurance tool for gastrectomy in oncological trials

BACKGROUND

Despite its recognized importance, there is currently no reliable tool for surgical quality assurance (SQA) of gastrectomy in surgical oncology. The aim of this study was to develop an SQA tool for gastrectomy and to apply this tool within the ADDICT Trial in order to assess the extent and completeness of lymphadenectomy.

METHODS

The operative steps for D1+ and D2 gastrectomy have been previously described in the literature and ADDICT trial manual. Two researchers also performed fieldwork in the UK and Japan to document key operative steps through photographs and semi-structured interviews with expert surgeons. This provided the steps that were used as the framework for the SQA tool. Sixty-two photographic cases from the ADDICT Trial were rated by three independent surgeons. Generalizability (G) theory determined inter-rater reliability. D-studies examined the effect of varying the number of assessors and photographic series they rated. Chi-square assessed intra-rater reliability, comparing how the individual assessor's responses corresponded to their global rating for extent of lymphadenectomy.

RESULTS

The tool comprised 20 items, including 19 anatomical landmarks and a global rating score. Overall reliability had G-coefficient of 0.557. Internal consistency was measured with a Cronbach's alpha score of 0.869 and Chi-square confirmed intra-rater reliability for each assessor as < 0.05.

CONCLUSIONS

A photographic surgical quality assurance tool is presented for gastrectomy. Using this tool, the assessor can reliably determine not only the quality but also the extent of the lymphadenectomy performed based on remaining anatomy rather than the excised specimen.

Comparative Prognostic Value of the National Institutes of Health Stroke Scale (NIHSS) and the Glasgow Coma Scale (GCS) in Supratentorial and Infratentorial Stroke Patients in Western India

Background Acute coronary syndrome is the most common cause of mortality; cerebral vascular accident ranks second. Stroke is the fourth most common cause of disability worldwide, with nearly 20 million people suffering a stroke every year around the world and an estimated five million dead. Slightly more than 85.5% of stroke-related deaths take place in developing countries. In short, blockage (thrombus or emboli) and decreased blood supply for cerebral tissues lead to a stroke that permanently damages brain tissue. A stroke is clinically defined as rapidly developing clinical symptoms of focal cerebral dysfunction lasting >24 hours or leading to death, as characterized by the World Health Organization (WHO). Objective The present study was designed to compare the efficacy of the National Institutes of Health Stroke Scale (NIHSS) and the Glasgow Coma Scale (GCS) in determining the prognosis of supratentorial and infratentorial stroke. Methods This observational prospective study was performed on over 100 patients admitted to Bharati Hospital, Sangli, who had cerebrovascular accidents from February 2018 to June 2019. Eligibility criteria were adults more than 18 years of age with clinical and computed tomography/magnet resonance imaging (CT/MRI) evidence consistent with acute stroke. Trauma and concomitant supra- and infratentorial strokes were excluded. GCS and NIH stroke scale scores were measured daily, and scores were noted on the first and last day of hospitalization. Statistical analysis was done using IBM SPSS Statistics for Windows, Version 22 (Released 2013; IBM Corp., Armonk, New York, United States), including mean, standard deviation, paired t-test, and Chi-square test. Results Out of 100 patients, 77% had suffered supratentorial strokes, and thus the other 23% had infratentorial strokes. Alcohol consumption was associated with a higher risk of infratentorial strokes, while smoking was linked to a higher risk of supratentorial strokes. Diabetes and hypertension did not differ statistically between the two groups. Compared to patients with supratentorial strokes, those who suffered from infratentorial strokes had a greater death rate and less favorable recovery results. Patients with supratentorial strokes who recovered completely or partially showed considerable improvements in their GCS scores, but patients with infratentorial strokes showed minimal to no improvement. On the other hand, the NIHSS score significantly improved in patients who achieved both complete or partial recovery and no improvement or mortality in both supratentorial and infratentorial stroke. NIHSS is preferred over GCS because it provides a better insight into morbidity and neurological outcomes of both types of strokes in comparison with GCS, which is more useful in predicting mortalities. Conclusion According to this study, supratentorial strokes were more common, whereas infratentorial strokes had a worse prognosis. Alcohol ingestion and smoking may have an impact on the location of a stroke. Compared to GCS, the NIHSS score provided a more thorough evaluation of stroke recovery, indicating its potential for better patient care.

The short- and long-term outcomes of laparoscopic D2 lymphadenectomy plus complete mesogastrium excision for lymph node-negative gastric cancer

BACKGROUND

Patients with T1-3N0M0 gastric cancer (GC) who undergo radical gastrectomy maintain a high recurrence rate. The free cancer cells in the mesogastric adipose connective tissue (Metastasis V) maybe the reason for recurrence in these individuals. We aimed to evaluate whether D2 lymphadenectomy plus complete mesogastrium excision (D2 + CME) was superior to D2 lymphadenectomy with regard to safety and oncological efficacy for T1-3N0M0 GC.

METHODS

Patients with T1-3N0M0 GC who underwent radical resection from January 2014 to July 2018 were retrospectively analyzed; there were 323 patients, of whom 185 were in the D2 + CME group and 138 in the D2 group. The primary endpoint was 5-year disease-free survival (DFS). Secondary endpoints include the 5-year overall survival (OS), recurrence pattern, morbidity, mortality, and surgical outcomes.

RESULTS

D2 + CME was associated with less intraoperative bleeding loss, a greater number of lymph nodes harvested, and less time to first postoperative flatus, but the postoperative morbidity was similar. The 5-year DFS was 95.6% (95% CI 92.7-98.5%) and 90.4% (95% CI 85.5-95.3%) in the D2 + CME group and the D2 group, respectively, with a hazard ratio (HR) of 0.455 (95% CI 0.188-1.097; p = 0.071). In terms of recurrence patterns, local recurrence was more prone to occur in the D2 group (p = 0.031). Subgroup analysis indicated that for patients with T1b-3N0M0 GC, the 5-year DFS in the D2 + CME group was considerably greater than that in the D2 group (95.3% [95% CI 91.6-99.0%] vs. 87.6% [95% CI 80.7-94.5%], HR 0.369, 95% CI 0.138-0.983; log-rank p = 0.043).

CONCLUSION

Laparoscopic D2 + CME for T1-3N0M0 GC is safe and feasible. Furthermore, it not only reduces the local recurrence rate but also improves the 5-year DFS in cases of T1b-3N0M0 GC.

Biomechanical characterization of the passive porcine stomach

The complex mechanics of the gastric wall facilitates the main digestive tasks of the stomach. However, the interplay between the mechanical properties of the stomach, its microstructure, and its vital functions is not yet fully understood. Importantly, the pig animal model is widely used in biomedical research for preliminary or ethically prohibited studies of the human digestion system. Therefore, this study aims to thoroughly characterize the mechanical behavior and microstructure of the porcine stomach. For this purpose, multiple quasi-static mechanical tests were carried out with three different loading modes, i.e., planar biaxial extension, radial compression, and simple shear. Stress-relaxation tests complemented the quasi-static experiments to evaluate the deformation and strain-dependent viscoelastic properties. Each experiment was conducted on specimens of the complete stomach wall and two separate layers, mucosa and muscularis, from each of the three gastric regions, i.e., fundus, body, and antrum. The significant preconditioning effects and the considerable regional and layer-specific differences in the tissue response were analyzed. Furthermore, the mechanical experiments were complemented with histology to examine the influence of the microstructural composition on the macrostructural mechanical response and vice versa. Importantly, the shear tests showed lower stresses in the complete wall compared to the single layers which the loose network of submucosal collagen might explain. Also, the stratum arrangement of the muscularis might explain mechanical anisotropy during tensile tests. This study shows that gastric tissue is characterized by a highly heterogeneous microstructure with regional variations in layer composition reflecting not only functional differences but also diverse mechanical behavior. STATEMENT OF SIGNIFICANCE: Unfortunately, only few experimental data on gastric tissue are available for an adequate material parameter and model estimation. The present study therefore combines layer- and region-specific stomach wall mechanics obtained under multiple loading conditions with histological insights into the heterogeneous microstructure. On the one hand, the extensive data sets of this study expand our understanding of the interplay between gastric mechanics, motility and functionality, which could help to identify and treat associated pathologies. On the other hand, such data sets are of high relevance for the constitutive modeling of stomach tissue, and its application in the field of medical engineering, e.g., in the development of surgical staplers and the improvement of bariatric surgical interventions.

The short- and long-term effect of membrane anatomy-guided laparoscopic D2 lymphadenectomy plus regional complete mesogastrium excision for locally advanced gastric cancer

OBJECTIVE

Retrospectively analyzed the short- and long-term efficacy between laparoscopic D2 lymphadenectomy plus regional complete mesogastrium excision (D2 + rCME) and traditional laparoscopic D2 in the treatment of patients with locally advanced gastric cancer (LAGC), in order to obtain more evidence for D2 + rCME gastrectomy.

METHODS

A total of 599 LAGC patients who underwent laparoscopy-assisted radical gastrectomy from January 2014 to December 2019, including 367 cases in the D2 + rCME group and 232 cases in the D2 group. Intraoperative and postoperative clinicopathological parameters, postoperative complications and long-term survival in the two groups were statistically analyzed.

RESULTS

No significant differences in the positive rate of mesogastric tumor deposits, the number of positive lymph nodes and postoperative length of stay were found between the two groups (P > 0.05). In the D2 + rCME group, intraoperative blood loss was significantly reduced (84.20 ± 57.64 ml vs. 148.47 ± 76.97 ml, P < 0.001), the time to first postoperative flatus and first liquid diet intake were significantly shortened (3[2-3] days vs. 3[3-3] days, P < 0.001; 7[7-8] days vs. 8[7-8] days, P < 0.001), and the number of lymph nodes dissected was greater (43.57 ± 16.52 pieces vs. 36.72 ± 13.83 pieces, P < 0.001). The incidence of complications did not significantly differ between the D2 + rCME group (20.7%) and D2 group (19.4%) (P > 0.05). Although there was no statistically difference in 3-year OS and DFS between the two groups. However, the trend was better in D2 + rCME group. In subgroup analysis, patients with positive tumor deposits (TDs) in the D2 + rCME group had significantly better 3-year DFS compared With D2 group (P < 0.05).

CONCLUSION

Laparoscopic D2 + rCME is safe and feasible for the treatment of LAGC and is characterized by less bleeding, greater lymph node dissection and rapid recovery, without increasing postoperative complications. D2 + rCME group showed a better trend of long-term efficacy, especially significant beneficial for LAGC patients who with positive TDs.

Short-term outcomes of D2 lymphadenectomy plus complete mesogastric excision for gastric cancer: a propensity score matching analysis

BACKGROUND

Our previous study has demonstrated the surgical advantages of D2 lymphadenectomy plus complete mesogastric excision (D2 + CME) in gastric cancer surgery. To further verify the safety of D2 + CME procedure, we conducted this large-scale, observational cohort study and applied propensity score matching (PSM) approach to compare D2 + CME with conventional D2 in terms of short-term outcomes in gastric cancer patients.

METHODS

Data on 855 patients from Tongji Hospital who underwent laparoscopic-assisted distal gastrectomy (LADG) with R0 resection (496 in the conventional D2 cohort and 359 in the D2 + CME cohort) between Dec 12, 2013 and Dec 28, 2017 were retrieved from prospectively maintained clinical database. After PSM analysis at a 1:1 ratio, each cohort included 219-matched patients. Short-term outcomes, including surgical results, morbidity, and mortality within 30 days after the operation, were collected and analyzed.

RESULTS

In this large-scale, observational cohort study based on PSM analysis, the D2 + CME procedure showed less intra-laparoscopic blood loss, more lymph node harvest, and faster postoperative flatus than the conventional D2 procedure. However, both the overall and severe postoperative adverse events (Clavien-Dindo classification grade ≥ III a) seemed comparable between two cohorts.

CONCLUSION

The present study showed that D2 + CME was associated with better short-term outcomes than conventional D2 dissection for patients with resectable gastric cancer.

Evaluating quality and completeness of gastrectomy for gastric cancer: review of surgical videos from the public domain

Background

YouTube^® has provided a forum to share surgical videos in the public domain which may be used for education. The quality of surgery and accompanying educational material is unknown. YouTube^® videos of gastrectomy with D2 lymphadenectomy (D2-LND) for gastric cancer were evaluated for quality and completeness.

Methods

YouTube^® was searched using the terms "D2 lymphadenectomy" and "Gastric Cancer" for open and laparoscopic videos. The Korean Laparoscopic Gastrointestinal Surgical Society (KLASS) outlined 22 steps that define quality and completeness of D2-LND. These guidelines were used to score D2-LND for each video. Four physician reviewers independently scored each surgical video. Scores were compared using Student's t-test.

Results

Ten laparoscopic and 10 open surgery videos were assessed. Each video was scored for quality and completeness and assigned a score out of 22. Mean score for open D2-LND was 15 (95% CI: 12.54-17.46). Mean score for laparoscopic D2-LND was 15.4 (95% CI: 14.34-16.46; P=0.77). The most consistently performed steps were the dissection of lymph node stations 1, 3, 4 and 5. The most commonly omitted steps were the dissection of lymph node station 6: exposure and identification of the lowest anterior superior pancreaticoduodenal vein; removal of the prepancreatic soft tissues above the lowest anterior superior pancreaticoduodenal vein; removal of the prepancreatic soft tissues above the level of the bifurcation of the anterior superior pancreaticoduodenal vein and right gastroepiploic vein.

Conclusions

There is a wide range of quality and completeness of D2-LND videos. On average, D2-LND videos are only two-thirds complete.

Complete mesogastric excision for locally advanced gastric cancer: short-term outcomes of a randomized clinical trial

Implementation of complete mesogastric excision in gastric cancer surgery, named D2 lymphadenectomy plus complete mesogastric excision (D2+CME), has recently been proposed as an optimal procedure. However, the safety and efficacy of D2+CME remain uncertain. In this randomized controlled trial, patients receiving D2+CME exhibit less intraoperative blood loss, more lymph node harvesting, and earlier postoperative flatus than patients receiving conventional D2 radical surgery. Univariate Cox regression analysis reveals that the risk ratio for postoperative flatus in D2+CME group is 1.247 (p = 0.044). Overall postoperative complications are comparable between the two groups, but complications are significantly less severe in the D2+CME group than the D2 group (Clavien-Dindo classification grade ≥ IIIa: 4 D2+CME patients [11.8%] versus 9 D2 patients [33.3%]; p = 0.041). In conclusion, our work shows that D2+CME is associated with better short-term outcomes and surgical safety than conventional D2 dissection for patients with advanced gastric cancer.

Gastric cancer patients receiving D2+CME exhibit less intraoperative blood loss

The number of lymph nodes harvested with D2+CME is significantly improved

D2+CME surgery could provide faster postoperative flatus

D2+CME is less likely to cause severe complications than conventional surgery

Surgical treatment of gastric cancer: Current status and future directions

Surgery is the most important and effective method for the treatment of gastric cancer. Since the first gastrectomy in the early 19th century, surgical treatment of gastric cancer has undergone more than 100 years of development. With the increasing understanding of gastric cancer and the promotion of a series of clinical trials, the concept of gastric cancer surgery has evolved from the initial "bigger is better" to today's "standardized surgery" and is developing towards individualized surgery focusing on accurate resection and quality of life. This trend has had a tremendous impact on the development of surgical treatments, such as minimally invasive surgeries, function-preserving surgeries, and the optimal extent of lymph node dissection. Understanding the development and current status of gastric cancer surgery and exploring the remaining academic controversies are goals that every gastric surgeon should constantly pursue. However, how should gastric cancer surgery develop in the future? What opportunities and challenges will we encounter? In this review, we elaborate on the development and current status of gastric cancer surgery based on a series of clinical studies and discuss the controversy in the development of gastric cancer surgery.

Superiority of log odds of positive lymph nodes (LODDS) for prognostic prediction after gastric cancer surgery: a multi-institutional analysis of 7620 patients in China

PURPOSE

To compare the 8th pN system with ratio-based and Log odds of positive lymph nodes (LODDS) staging systems for predicting the overall survival (OS) of gastric cancer (GC) patients after curative gastric resection.

METHODS

We analyzed, retrospectively, clinicopathologic and prognostic data from three Chinese medical centers, on 7620 patients who underwent curative surgery for GC. We established a hypothetical tumor-LODDS-metastasis (TLM) and tumor-ratio-metastasis (TRM) staging system. The relative discriminative abilities of the different staging systems were assessed using Akaike's Information Criterion (AIC), a linear trend chi-square test, and a likelihood ratio chi-square test.

RESULTS

The cut-off points of the LODDS were set as: ≤ - 1.5, - 1.5 to - 1.0, - 1.0 to - 0.5, - 0.5 to 0, and > 0. There were significant differences in the survival of patients in different LODDS classifications for each pN or LNR group. When stratified by the LODDS classification, the prognosis was more homologous according to the pN or lymph-node ratio (LNR) classifications. The modified TLM staging system had better discriminatory ability and better optimistic prognostic stratification than the 8th TNM or the TRM staging systems for predicting the prognosis of patients with GC.

CONCLUSIONS

The LODDS staging system was superior to other lymph-node classifications for predicting the prognosis of patients undergoing gastrectomy GC. LODDS may be incorporated into a GC staging system if these results are confirmed by other studies.

LESSONS LEARNED ANALYZING COMPLICATIONS AFTER LAPAROSCOPIC TOTAL GASTRECTOMY FOR GASTRIC CANCER

Background:

Laparoscopic surgery has been gradually accepted as an option for the surgical treatment ofgastric cancer. There are still points that are controversial or situations that are eventually associated with intra-operative difficulties or postoperative complications.

Aim:

To establish the relationship between the difficulties during the execution of total gastrectomy and the occurrence of eventual postoperative complications.

Method:

The operative protocols and postoperative evolution of 74 patients operated for gastriccancer, who were subjected to laparoscopic total gastrectomy (inclusion criteria) were reviewed. The intraoperative difficulties recorded in the operative protocol and postoperative complications of a surgical nature wereanalyzed (inclusion criteria). Postoperative medical complications were excluded (exclusion criteria). For the discussion, an extensive bibliographical review was carried out.

Results:

Intra-operative difficulties or complications reported correspond to 33/74 and of these; 18 events (54.5%) were related to postoperative complications and six were absolutely unexpected. The more frequent were leaks of the anastomosis and leaks of the duodenal stump; however, other rare complications were observed. Seven were managed with conservative measures and 17 (22.9%) required surgical re-exploration, with a postoperative mortality of two patients (2.7%).

Conclusion:

We have learned that there are infrequent and unexpected complications; the treating team must be mindful of and, in front of suspicion of complications, anappropriate decision must be done which includes early re-exploration. Finally, after the experience reported, some complications should be avoided.

Impact of the number of examined lymph nodes on stage migration in node-negative gastric cancer patients: a Chinese multi-institutional analysis with propensity score matching

BACKGROUND

This propensity score matching (PSM) analysis assessed the influence of examined lymph nodes (ELNs) count on stage migration and survival in node-negative (pN0) gastric cancer (GC) patients.

METHODS

We performed a retrospective analysis of 7,620 GC patients who underwent curative gastric resection in three Chinese medical centers. PSM was used to reduce the confounding effects between the pN0 GC patients with ELNs <16 or ≥16. Survival differences among various subgroups of GC patients were analyzed to assess the impact of the ELNs count on the stage migration in accordance with the overall survival (OS) of pN0 GC patients.

RESULTS

After matching, the backgrounds of pN0 GC patients in the ELNs <16 (n=825) and ELNs ≥16 (n=826) groups were well-balanced. Survival analyses revealed that the ELNs count was positively correlated with the OS (P=0.001). Multiple Cox analysis indicated that the ELNs count was an independent predictor of the OS in pN0 GC patients. Stage migrations were mainly detected in subgroups of pN0 GC patients with specific pTNM stages, as follows: (I) pT2N0M0 with ELNs <16 vs. pT3N0M0 with ELNs ≥16; (II) pT3N0M0 with ELNs <16 vs. pT3N1M0 with ELNs ≥16; and (III) pT4aN0M0 with ELNs <16 vs. pT4aN1M0 with ELNs ≥16.

CONCLUSIONS

We show that stage migration can be detected in pN0 GC patients, and that it could be gradually reduced or prevented by increasing the ELNs count.

The Significant Influence of the Neuroendocrine Component on the Survival of Patients with Gastric Carcinoma Characterized by Coexisting Exocrine and Neuroendocrine Components

Background

Gastric adenocarcinoma patients with a neuroendocrine (NE) component are frequently observed in routine practice. Several previous studies have investigated the influence of a NE component on the survival of these patients; however, the results were inconsistent.

Methods

We retrospectively investigated a consecutive series of 95 gastric adenocarcinoma patients with a NE component and 190 gastric adenocarcinoma patients without a NE component. We adopted 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 90% as the cut-off proportions of the NE component, respectively, and analyzed the patients' overall survival according to the proportion of the NE component.

Results

The 1-, 3-, and 5-year actual survival rates of the patients with a NE component were 90.1%, 72.3%, and 67.2%, respectively, and for those without a NE component 94.2%, 79.3%, and 75.7%, respectively. The multivariate analysis showed that the patients with NE components >70% (HR: 2.156; 95% CI: 1.011, 4.597; p=0.047) and >90% (HR: 2.476; 95% CI: 1.088, 5.634; p=0.031) had significantly worse survival than those without a NE component. Only the diameter of tumors (>4.64 cm) (HR: 2.585; 95% CI: 1.112, 6.006; p=0.027) and pN3 (HR: 2.953; 95% CI: 1.051, 8.293; p=0.040) were independently associated with worse overall survival for gastric adenocarcinoma patients with a NE component (all p<0.05).

Conclusion

Gastric adenocarcinoma patients with a NE component >70% and >90% have significantly worse survival than those without a NE component. Only the diameter of tumors and the number of metastatic lymph nodes are independent prognostic factors for gastric adenocarcinoma patients with a NE component.

CURRENT STATUS OF THE MULTIDISCIPLINARY TREATMENT OF GASTRIC ADENOCARCINOMA

Background:

The complexity of the management of gastric cancer requires a multidisciplinary evaluation of patients with this tumor. Several treatments have been employed, associated to the surgical resection.

Objective:

To review the available therapeutic alternatives for the treatment of gastric adenocarcinoma.

Methods:

A review of selected articles on multidisciplinary treatment of gastric adenocarcinoma in the Pubmed and Medline databases between 2000 and 2017 was carried out. The following headings were related: stomach cancer, treatment, chemotherapy and radiotherapy.

Results:

There are several valid alternatives, with good results for the treatment of gastric cancer: chemoradiotherapy or chemotherapy in the adjuvant scenario; perioperative chemotherapy; and chemoradiotherapy after neoadjuvance with isolated chemotherapy.

Conclusion:

Current evidences suggest that combined multidisciplinary treatment is superior to surgery alone. However, the optimal treatment regimen is not yet established, and depends on a number of factors, especially the type of surgical resection employed. Therefore, the therapeutic decision should be made by a multidisciplinary team, assessing patient’s personal characteristics, biology of the tumor, residual disease, risks and side effects.

Detection of carcinoembryonic antigen in peritoneal fluid of patients undergoing laparoscopic distal gastrectomy with complete mesogastric excision

Background

Surgery for gastric cancer may result in free intraperitoneal cancer cells. This study aimed to determine whether laparoscopic gastrectomy with complete mesogastric excision (D2 + CME) reduces the number of free intraperitoneal cancer cells.

Methods

Patients with gastric cancer who had a conventional D2 or D2 + CME laparoscopic distal gastrectomy between April 2015 and February 2017 were included in the study. Intraoperative peritoneal washings were collected before and after tumour resection. Reverse transcriptase–quantitative real-time PCR for carcinoembryonic antigen (CEA) was used to assess the presence of gastric cancer cells.

Results

Eighty-five patients underwent conventional D2 lymphadenectomy and 76 had the D2 + CME procedure. Of 161 peritoneal fluid samples obtained before gastrectomy, 137 (D2, 72; D2 + CME, 65) had low CEA expression indicative of no cancer cells. After gastrectomy, high CEA expression was detected in 23 of the 72 samples (32 per cent) from patients in the D2 group, and in ten of the 65 samples (15 per cent) from the D2 + CME group. In the overall cohort, mean CEA expression level after gastrectomy was lower in the D2 + CME group than in the D2 group (P = 0·0038). In patients with low CEA expression before gastrectomy, disease-free survival in the D2 + CME group was better than that in the D2 group (P = 0·033).

Conclusion

Laparoscopic distal gastrectomy with complete mesogastric excision reduces the number of free intraperitoneal cancer cells and is associated with a better disease-free survival than conventional D2 gastrectomy.

Total iron-binding capacity is a novel prognostic marker after curative gastrectomy for gastric cancer

BACKGROUND

Patients with gastric cancer (GC) are affected by changes in iron status. Before surgery, GC patients are likely to have iron-deficiency anemia; and after gastrectomy, patients suffer from low nutritional status and low iron. This study investigated preoperative iron status associated with prognosis after curative gastrectomy for gastric cancer.

METHODS

We evaluated preoperative serum hemoglobin (Hgb), Fe and total iron-binding capacity (TIBC) in 298 patients who underwent curative gastrectomy for GC without preoperative chemotherapy, and analyzed these factors' associations with prognosis after surgery.

RESULTS

Of the 298 patients, 129 (43.2%) had low Hgb levels, and 33 (11.1%) had low TIBC (< 260 µg/dl) that was not associated with Hgb or Fe level. Patients with low TIBC were significantly associated with older age (≥ 65 years old; P = 0.0085), low albumin (< 3.9 g/dl; P = 0.0388) and high CRP (≥ 0.15 mg/dl; P = 0.0018) in multivariate analysis. Low Fe (< 60 µg/dl) was not associated with disease-free survival (DFS) or overall survival (OS); however, low Fe was associated with longer cancer-specific survival in Stage III GC patients (P = 0.0333). Both low Hgb and low TIBC were significantly associated with shorter DFS (Hgb: P = 0.0433; TIBC: P < 0.0001) and shorter OS (Hgb: P = 0.0352; TIBC: P < 0.0001). Low TIBC were significantly associated with shorter DFS (HR 2.167, 95% CI 1.231-3.639, P = 0.0086) and shorter OS (HR 2.065, 95% CI 1.144-3.570, P = 0.0173) in multivariate Cox hazard regression analysis.

CONCLUSIONS

Preoperative serum TIBC level of GC patients who undergo curative gastrectomy is a novel prognostic marker in univariate and multivariate analyses.

Intraoperative Pancreatic Injury Gives Rise to Severe Postoperative Pancreatic Fistula: Results of a Review of Unedited Videos of the Laparoscopic Surgical Procedures

Objective

To examine risk factors for and causes of severe postoperative pancreatic fistula (sPOPF) after laparoscopic gastrectomy (LG).

Summary of Background Data

There are few reports on POPF after LG.

Methods

Between February 2012 and March 2014, we examined 86 patients who underwent LG, comparing them with 33 patients who underwent open gastrectomy (OG) for gastric cancer. Risk factors for severe POPF (sPOPF) of Clavien–Dindo grade IIIa or higher were examined. To investigate causes of sPOPF, we reviewed unedited video recordings of laparoscopic surgical procedures.

Results

sPOPF occurred in 3 patients (3.5%) after LG and 1 patient (3.0%) after OG, indicating no significant difference (P = 0.901). Univariate analysis showed no significant risk factors for sPOPF after LG. By reviewing video recordings, all 3 patients with sPOPF after LG had direct pancreatic injury by ultrasonically activated device (USAD) during peripancreatic lymphadenectomy. In 2 patients, pancreas was injured while the contour of pancreas was obscured by bleeding. Durations of drain placement and postoperative hospitalization were longer for patients with sPOPF than for those without POPF or grades I and II POPF (P = 0.003, 0.018; respectively).

Conclusions

No risk factors for sPOPF after LG could be identified. USAD-induced direct pancreatic injury resulted in sPOPF, which significantly complicated the postoperative clinical course. Direct pancreatic injury can occur whether patient has previously reported risk factors (i.e., male, high body mass index, distal pancreatectomy) or not. To prevent pancreatic injury, surgeons should manage hemostasis and keep good surgical field to recognize the contour of pancreas accurately.

Prognostic and predictive value of metastatic lymph node ratio in stage III gastric cancer after D2 nodal dissection

Introduction

This study is to evaluate the prognostic and predictive value of metastatic lymph node ratio (MLR) in stage III gastric cancer following radical D2 dissection.

Methods

87 patients who underwent radical resection with D2 lymphadenectomy were retrospectively evaluated. The median age was 60 with a 2:1 ratio of male/female. Of these 87 patients, 83 underwent total gastrectomy, the remaining 4 underwent subtotal gastrectomy and 57 patients received adjuvant chemotherapy with fluoropyrimidines. Indexes of lymph node involvement and other clinicopathological data were analyzed. Survival was determined by the Kaplan-Meier method and log-rank test. Multivariate analysis was performed using the Cox proportional hazards model.

Results

Median total retrieved lymph node number was 35 (range: 10-104) with median metastatic lymph node amount of eight (range: 0-71). Median survival time was 31.7 months with a 3-year survival rate of 36.4%. Patients were divided into four groups according to MLR: MLR0, 0; MLR1, <0.1; MLR2, 0.1-0.25; MLR3, >0.25. After median follow-up of 31 months, median OS rates of MLR0 to MLR3 were 37.1m, 35.9m, 31.5m and 20.8m, respectively (p=0.013). Median OS rates were significantly different among subgroups: 39.3m and 36.5m were obtained for low subgroups (MLR<0.24) with or without adjuvant chemotherapy, respectively; 22.9m and 12.2m were found in high subgroups (MLR>0.24) with and without chemotherapy, respectively (p=0.002). Finally, MLR constituted an independent prognostic factor in multivariable analysis.

Conclusions

After R0 resection with D2 lymphadenectomy for stage III gastric cancer, MLR constitutes an effective prognostic indicator. Patients with high MLR may benefit the most from adjuvant chemotherapy.

East Versus West: Differences in Surgical Management in Asia Compared with Europe and North America

In recent decades, there has been considerable worldwide progress in the treatment of gastric cancer. Gastrectomy with a modified D2 lymphadenectomy (sparing the distal pancreas and spleen) has increasingly gained acceptance as a preferable standard surgical approach among surgeons in the East and the West. Despite growing consensus significant differences still exist in surgical techniques in clinical trials and clinical practices secondary to variations in epidemiology, clinicopathologic features, and surgical outcomes among geographic regions. In addition, Western physicians tend to prefer adjuvant chemotherapy and radiotherapy after surgery instead of using S-1 chemotherapy, as is the preference in the East.

Current status of surgical treatment of gastric cancer in the era of minimally invasive surgery in China: Opportunity and challenge

Gastric cancer is one of the most common cancers in China. In the past decade, with the developments in surgical instruments and technologies, minimally invasive surgery has rapidly become an accepted treatment for gastric cancer in China. Many Chinese surgeons and researchers have contributed to the rapid evolution of minimally invasive surgery for gastric cancer. Their efforts have transformed into unique laparoscopic technique, workshops, academic communications, education and international communications in China. Meanwhile, many retrospective comparative trials and randomized controlled trials have revealed the advantages in minimally invasive surgery for gastric cancer. However, multicenter randomized controlled trials are still needed to delineate significantly quantifiable differences between laparoscopic and open gastrectomy. With more and more experience has accumulated, laparoscopic gastrectomy has been performed on older and overweight patients. Moreover, advanced minimally invasive techniques, such as modified laparoscopic spleen-preserving splenic hilum lymphadenectomy, various laparoscopic gastric reconstruction methods and robotic gastrectomy have been developed. It seems that China owns the potential to keep up with her neighbor, Japan and Korea, to become one of leading countries utilizing minimally invasive surgery for gastric cancer.

Enhanced recovery after surgery with laparoscopic radical gastrectomy for stomach carcinomas

AIM: To study the efficacy of the enhanced recovery after surgery (ERAS) program in laparoscopic radical gastrectomy for stomach carcinomas.

METHODS: From June 2010 to December 2012, 61 gastric cancer patients who underwent laparoscopic-assisted radical gastrectomy with D2 lymphadenectomy at First Hospital of Jilin University were enrolled in this randomized controlled trial. (Clinical Trials.gov, registration ID: NCT01955096). The subjects were divided into the ERAS program group and the conventional control group. The clinical characteristics, recovery variables, and complications of patients were analyzed.

RESULTS: The time to first ambulation, oral food intake, and time to defecation were significantly shorter in the ERAS group (n = 30), compared to the conventional group (n = 31; P = 0.04, 0.003, and 0.01, respectively). The postoperative hospital stay was less in the ERAS group (6.8 ± 1.1 d) compared to the conventional group (7.7 ± 1.1 d) (P = 0.002). There was no significant difference in postoperative complications between the ERAS (1/30) and conventional care groups (2/31) (P = 1.00). There were no readmissions or mortality during the 30-d follow-up period.

CONCLUSION: The ERAS program is associated with a shorter hospital stay in gastric cancer patients undergoing laparoscopic radical gastrectomy. The ERAS protocol is useful in the treatment of gastric cancer.

Superior antitumor activity of trastuzumab combined with capecitabine plus oxaliplatin in a human epidermal growth factor receptor 2-positive human gastric cancer xenograft model

In the treatment of human epidermal growth factor receptor 2 (HER2)-positive advanced gastric or gastroesophageal junction cancer, it has been reported that the combination of trastuzumab with capecitabine plus cisplatin, or with 5-fluorouracil (5-FU) plus cisplatin, significantly increased overall survival compared with chemotherapy alone (ToGA trial). In addition, adjuvant therapy with capecitabine plus oxaliplatin (XELOX) improved the survival of patients who received curative D2 gastrectomy (CLASSIC trial). However, the efficacy of the combination of trastuzumab with XELOX for patients with HER2-positive gastric cancer remains unknown. The aim of this study, was to investigate the efficacy of the combination of trastuzumab with XELOX in a HER2-positive human gastric cancer xenograft model. Combination treatment with these three agents (trastuzumab 20 mg/kg, capecitabine 359 mg/kg and oxaliplatin 10 mg/kg), was found to exhibit a significantly stronger antitumor activity in NCI-N87 xenografts compared with either trastuzumab or XELOX alone. In this model, treatment with trastuzumab alone or trastuzumab plus oxaliplatin enhanced the expression of thymidine phosphorylase (TP), a key enzyme in the generation of 5-FU from capecitabine in tumor tissues. In in vitro experiments, trastuzumab induced TP mRNA expression in NCI-N87 cells. In addition, NCI-N87 cells co-cultured with the natural killer (NK) cell line CD16(158V)/NK-92 exhibited increased expression of TP mRNA. When NCI-N87 cells were cultured with CD16(158V)/NK-92 cells in the presence of trastuzumab, the mRNA expression of cytokines reported to have the ability to induce TP was upregulated in tumor cells. Furthermore, a medium conditioned by CD16(158V)/NK-92 cells also upregulated the expression of TP mRNA in NCI-N87 cells. These results suggest that trastuzumab promotes TP expression, either by acting directly on NCI-N87 cells, or indirectly via a mechanism that includes trastuzumab-mediated interactions between NK and NCI-N87 cells. Therefore, the combination of trastuzumab with XELOX may be a potent therapy for HER2-positive gastric cancer.

Prognostic significance of metastatic lymph node number, ratio and station in gastric neuroendocrine carcinoma

The objective of this study was to analyze the prognostic significance of metastatic lymph node status in gastric neuroendocrine carcinoma (GNEC) patients following radical gastrectomy. A consecutive series of 73 patients who underwent gastrectomy between 1999 and 2011 for GNEC was retrospectively reviewed. Indexes of lymph node involvement (the pN classification, metastatic lymph node number [MLNn], ratio [MLNr], and station [MLNs]) and other clinicopathological data were analyzed. Fifty-four patients met the inclusion criteria and were enrolled in the study. Among them, 44 patients (81 %) were found to have lymph node metastases. The median survival time of the entire cohort was 63.2 (range, 14-153) months with 3- and 5-year survival rates of 88.9 and 47.9 %, respectively. The median total number of lymph nodes, MLNn, and MLNr were 19 (range, 10-56), 5 (range, 1-21), and 25 % (6-100 %), respectively. Cox regression analysis revealed pN classification = 1, MLNn >2, MLNr >0.1, and MLNs = 2, and distant metastases influenced prognosis independently (P = 0.0266, 0.0091, 0.0031, 0.0119, and 0.0021, respectively). In addition to the pN classification, indexes of metastatic lymph node involvement, including MLNn, MLNr, and MLNs, were all significant predictors of survival in GNEC patients. Distant metastasis was also a significant prognostic factor. These indexes proved to be accurate and important supplements to survival factors, which may improve risk classification of GNEC patients.

Identification of EGFR expression status association with metastatic lymph node density (ND) by expression microarray analysis of advanced gastric cancer

Metastatic lymph node density (ND) has been reproducibly proven to be a prognostic factor in gastric cancer. The molecular mechanisms that underlie this aggressiveness are underexplored. Here, we aimed to identify molecules associated with this unique phenotype. Tumor specimens from patients with stage III gastric cancer with high or low ND (n = 4 for both) were compared at the mRNA level using Affymetrix microarray (harboring 54,675 genes). The expression data were prioritized, and genes that correlated with ND were selected. Ultimately, the EGFR was validated as such a candidate molecule in patients with primary advanced gastric cancer who underwent standard treatment (n = 167). Expression data of the microarray were prioritized based on gene expression ratio and frequency of gene expression. The first priority genes to be selected were genes that are known to be amplified in cancer, which included NKX2.1, CHST9, CTNND2, SLC25A27, FGFR2, EGFR, and PTGER1. Of these genes, the EGFR gene was of particular interest. EGFR expression in primary gastric cancer was examined using immunohistochemistry (IHC). The Student's t-test elucidated a significant difference in EGFR expression between IHC 2+/3+ and IHC 1+ according to ND (P = 0.0035). The Chi-square test also indicated a significant difference between high and low levels of EGFR immunohistochemical staining (IHC2+/3+ and IHC1+, respectively) and ND status (P = 0.0023). According to the least squares method, as ND increased, the risk that EGFR staining levels changed from IHC 1+ to IHC 2+ also increased. In this study, we determined that high EGFR expression may underlie the aggressive mechanism of advanced gastric cancer with high ND.

Adjuvant Chemotherapy with Docetaxel, Cisplatin, and Continuous-Infusion 5-Fluorouracil for Gastric Cancer: A Phase II Study

PURPOSE

This study evaluated the efficacy and safety of adjuvant chemotherapy with the docetaxel plus cisplatin and 5-fluorouracil (5-FU) (DCF) regimen in patients with gastric cancer.

PATIENTS AND METHODS

Thirty-two patients with gastric or gastroesophageal junction cancer were enrolled in this study after undergoing radical resection. The patients received the following chemotherapy: docetaxel (60 mg/m(2)) on day 1, cisplatin (12 mg/m(2) per day) on days 1 to 5, and 5-FU (2500 mg/m(2)) continuous infusion for 120 hours, repeated every 3 weeks for six cycles. The primary end point was disease-free survival (DFS).

RESULTS

The median DFS was 17.0 months. The 1-year DFS was 72%, and the 2-year DFS was 37.5%. The median overall survival was 28.0 months. Using univariate analysis, the technique of lymph node dissection was a predictor for postoperative relapse. The median DFS was 15.0 months in the D1 group and 18.0 months in the D2 group (P = .043). The most frequent grade 3/4 adverse events were neutropenia (56.25%), diarrhea (9.38%), nausea (6.25%), and vomiting (6.25%); 12.5% of patients developed febrile neutropenia. There were no chemotherapy-related deaths.

CONCLUSIONS

The modified DCF regimen is an effective adjuvant chemotherapy in gastric cancer. Hematologic toxicity was frequent but manageable. This regimen merits further investigation.

Optimal management of gastric cancer: results from an international RAND/UCLA expert panel

OBJECTIVE

Defining processes of care, which are appropriate and necessary for management of gastric cancer (GC), is an important step toward improving outcomes.

METHODS

Using a RAND/UCLA Appropriateness Method, an international multidisciplinary expert panel created 22 statements reflecting optimal management. All statements were scored for appropriateness and necessity.

RESULTS

The following tenets were scored appropriate and necessary: (1) preoperative staging by computed tomography of abdomen/pelvis; (2) positron-emission tomographic scans not routinely indicated; (3) consideration for adjuvant therapy; (4) further clinical trials; (5) multidisciplinary decision making; (6) sufficient support at hospitals; (7) assessment of 16 or more lymph nodes (LNs); (8) in metastatic disease, surgery only for palliation of major symptoms; (9) surgeons experienced in GC management; (10) and surgeons experienced in both GC management and advanced laparoscopic surgery for laparoscopic resection. The following were scored appropriate, but of indeterminate necessity: (1) diagnostic laparoscopy before treatment; (2) a multidisciplinary approach to linitis plastica; (3) genetic assessment for diffuse GC and family history, or age less than 45 years; (4) endoscopic removal of select T1aN0 lesions; (5) D2 LN dissection in curative intent cases; (6) D1 LN dissection for early GC or patients with comorbidities; (7) frozen section analysis of margins; (8) nonemergent cases performed in a hospital with a volume of more than 15 resections per year; and (9) by a surgeon with more than 6 resection per year.

CONCLUSIONS

The expert panel has created 22 statements for the perioperative management of GC patients, to provide guidance to clinicians and improve the care received by patients.

Lymph node ratio is a critical prognostic predictor in gastric cancer treated with S-1 chemotherapy

BACKGROUND

S-1 is an oral anticancer drug widely used in postoperative adjuvant therapy for patients in Japan with stage II/III gastric cancer. Candidates for more intense adjuvant treatments need to be identified, particularly among patients with stage III cancer.

METHODS

Univariate and multivariate analyses were conducted for patients with stage II/III gastric cancer who underwent surgery and received S-1 postoperatively between 2000 and 2010.

RESULTS

Factors indicating poor prognosis identified by univariate analysis include male sex (P = 0.022), age ≥67 years (P = 0.021), intestinal-type histology (P = 0.049), lymph node ratio ≥16.7 % (P < 0.0001), open surgery (P = 0.039), as well as the 13th JGCA stage (P < 0.0001) and the 14th JGCA/7th International Union Against Cancer (UICC) stage (P < 0.0001). Multivariate analysis revealed that lymph node ratio ≥16.7 % and intestinal-type histology were significant as predictors of prognosis, independent from the pathological stages. Based on these and other findings, stage IIIC cancer on the 14th JGCA/7th UICC stage system in combination with the lymph node ratio could identify patients with extremely high risk for recurrence

CONCLUSIONS

Our current findings suggest that lymph node ratio ≥16.7 % in combination with the new staging system could be a useful prognostic indicator in advanced gastric cancer. Because these high-risk patients cannot be identified preoperatively by any diagnostic tool, further improvement in postoperative adjuvant therapy is warranted.

Clinicopathologic characteristics and outcomes of surgery of middle-third gastric cancer

Many issues of middle-third gastric cancer need to be address for obtaining preferably clinical treatment. The objective of this retrospective study was to analyze clinicopathologic characteristics and results of surgery for 113 middle-third gastric cancer patients admitted to our hospital. Retrospective cohort analyses of clinicopathologic data and postoperative prognosis of 113 middle-third gastric cancer patients who underwent curative resection between January 1997 and December 2003 were reviewed. Compared with lower-third gastric cancer patients, middle-third gastric cancer patients had significantly lower 5-year survival rate (P < 0.001) and higher recurrence rate (P < 0.001). With the Cox proportional hazards model analysis, the types of gastrectomy (hazard ratio (HR) = 0.495, P = 0.012) and ratio between metastatic and dissected lymph nodes (RML) (HR = 1.681, P < 0.001) were identified as the independent predictors of overall survival (OS) of middle-third gastric cancer patients. Besides, only RML (HR = 3.026, P < 0.001) was an independent predictor of recurrence for middle-third gastric cancer patients after surgery identified using the logistic regression analysis. The prognosis of middle-third gastric cancer was significantly worse than lower-third gastric cancer. RML was a key indicator for OS and recurrence of middle-third gastric cancer.

Evaluation of serum high-density lipoprotein cholesterol levels as a prognostic factor in gastric cancer patients

BACKGROUND AND AIM

Although there are some reports of an adverse effect of low serum high-density lipoprotein cholesterol (HDL-C) levels on gastrointestinal cancers, the specific correlation between serum HDL-C levels and gastric cancer remains unknown.

METHODS

Preoperative serum HDL-C levels were retrospectively examined in 184 patients who had undergone gastrectomy. The patients who had undergone gastrectomy were divided into two groups: the normal-HDL-C group and the low-HDL-C group. We examined the characteristics and outcomes of these two groups. Univariate and multivariate analyses were performed to investigate the association between serum HDL-C levels and gastric cancer.

RESULTS

There was no significant difference between the groups in terms of the progression of gastric cancer. In the low-HDL-C group, lymphatic and vascular invasion was significantly increased. The prognosis of the patients in the normal-HDL-C group was significantly better than those in the low-HDL-C group.

CONCLUSIONS

In this study, a positive correlation between low preoperative serum HDL-C levels and prognosis for gastric cancer was demonstrated. Serum HDL-C level may be a clinical prognostic factor for gastric cancer patients.

Ratio between negative and positive lymph nodes is suitable for evaluation the prognosis of gastric cancer patients with positive node metastasis

OBJECTIVE

To date, there is no consensus to evaluate the most appropriate category of the nodal metastasis for precise predication the prognosis of gastric cancer patients with positive node metastasis after curative surgery.

METHODS

We retrospectively analyzed the clinicopathologic characteristics and overall survival (OS) of 299 gastric cancer patients with positive node metastasis after curative surgery for evaluation the optimal category of the nodal metastasis.

RESULTS

With the univariate and multivariate survival analyses, the depth of primary tumor invasion was identified as the independent predicators with the OS of 299 gastric cancer patients with nodal metastasis postoperatively, as were the number of positive lymph nodes (PLNs), the number of negative lymph nodes (NLNs), and the ratio between negative and positive lymph nodes (RNPL). The RNPL was identified to be more suitable for predication the OS of gastric cancer patients with positive node metastasis than the ratio between positive and dissected lymph nodes (RPDL) by using the stratum procedure of survival analysis. Besides, we found both PLNs and NLNs were independently correlated with OS of gastric cancer patients with nodal metastasis when RNPL, instead of RPDL, was controlled in the partial correlation model.

CONCLUSIONS

RNPL, a new category of the nodal metastasis, was suitable for predication the OS of gastric cancer patients with nodal metastasis after curative resection, as were the PLNs, and NLNs.

Minimally invasive approaches for gastric cancer-Japanese experiences

Since development of laparoscopy-assisted distal gastrectomy with lymph node dissection in 1991 in Japan, laparoscopic gastrectomy (LAG) is improving and evolving. Recently, advanced LAG techniques including D2 lymph node dissection or anastomosis after total gastrectomy have been developed. Retrospective and prospective multicenter studies have been conducted for early and non-early gastric cancers to establish high-quality evidence. This review summarizes the current trends of minimally invasive approaches for gastric cancer based on current Japanese experiences.

Long-term outcomes and feasibility with laparoscopy-assisted gastrectomy for gastric cancer

Purpose

Recently, laparoscopy-assisted gastrectomy (LAG) has been widely accepted modality for early gastric cancer in Korea. The indication of LAG may be extended in an experienced institution. In our institution, the first case of laparoscopy-assisted gastrectomy (LAG) for gastric cancer was performed in May 1998. We retrospectively reviewed the long-term oncologic outcomes over 12 years to clarify the feasibility of LAG for gastric cancer.

Materials and Methods

The authors retrospectively analyzed 753 patients who underwent LAG for gastric cancer, from May 1998 to August 2010. We reviewed clinicopathological features, postoperative outcomes, mortality and morbidity, recurrence, and survival of LAG for gastric cancer.

Results

During the time period, 3,039 operations for gastric cancer were performed. Among them, 753 cases were done by LAG (24.8%). There were 69 cases of total gastrectomy, 682 subtotal gastrectomies, and 2 proximal gastrectomies. According to TNM stage, 8 patients were in stage 0, 619 in stage I, 88 in stage II, and 38 in stage III. The operation-related complications occurred in 77 cases (10.2%). Median follow-up period was 56.2 months (range 0.7~165.6 months). Twenty-five patients (3.3%) developed recurrence, during the follow-up period. The overall 5-year and disease free survival rates were 97.1% and 96.3%, respectively.

Conclusions

The number of postoperative complications and survival rates of our series were comparable to the results from that of other reports. The authors consider LAG to be a feasible alternative for the treatment of early gastric cancer. However, rationale for laparoscopic surgery in advanced gastric cancer has yet to be determined.

Evaluation of modified estimation of physiologic ability and surgical stress in colorectal carcinoma surgery

BACKGROUND

We recently modified Estimation of Physiologic Ability and Surgical Stress, our prediction scoring system.

OBJECTIVE

This study evaluated the usefulness of our modified version for colorectal carcinoma in comparison with existing models.

DESIGN

This investigation studied a multicenter cohort.

SETTINGS

The study was conducted in regional referral hospitals in Japan.

PATIENTS

Patients were included who underwent elective surgery for colorectal carcinoma.

MAIN OUTCOME MEASURES

Postoperative morbidity, mortality, and predicted mortality rates for original and modified Estimation of Physiologic Ability and Surgical Stress were investigated in 2388 patients in comparison with existing European models.

RESULTS

Among the models, the modified Estimation of Physiologic Ability and Surgical Stress demonstrated the highest discriminatory power in terms of in-hospital mortality (area under receiver operating characteristic curve: 0.84 for Estimation of Physiologic Ability and Surgical Stress, 0.87 for modified Estimation of Physiologic Ability and Surgical Stress, 0.84 for Portsmouth modification of POSSUM, 0.74 for ASA status-based model), as well as 30-day mortality (area under receiver operating characteristic curve: 0.82 for Estimation of Physiologic Ability and Surgical Stress, 0.84 for modified Estimation of Physiologic Ability and Surgical Stress, 0.81 for POSSUM, 0.78 for colorectal POSSUM, 0.76 for Association of Coloproctology of Great Britain and Ireland score). British models, in general, overpredicted postoperative mortality rates by more than 10 times.

LIMITATIONS

The current study analyzed only the Japanese population treated in medium-volume centers.

CONCLUSIONS

Among the models, modified Estimation of Physiologic Ability and Surgical Stress was the most accurate in predicting postoperative mortality in colorectal carcinoma surgery. These findings should be validated in Western populations, because the Japanese population may differ from Western populations in terms of body shape or reserve capacity.

Lymph node metastasis of gastric cancer

Despite a decrease in incidence in recent decades, gastric cancer is still one of the most common causes of cancer death worldwide [1]. In areas without screening for gastric cancer, it is diagnosed late and has a high frequency of nodal involvement [1]. Even in early gastric cancer (EGC), the incidence of lymph node (LN) metastasis exceeds 10%; it was reported to be 14.1% overall and was 4.8 to 23.6% depending on cancer depth [2]. It is important to evaluate LN status preoperatively for proper treatment strategy; however, sufficient results are not being obtained using various modalities. Surgery is the only effective intervention for cure or long-term survival. It is possible to cure local disease without distant metastasis by gastrectomy and LN dissection. However, there is no survival benefit from surgery for systemic disease with distant metastasis such as para-aortic lymph node metastasis [3]. Therefore, whether the disease is local or systemic is an important prognostic indicator for gastric cancer, and the debate continues over the importance of extended lymphadenectomy for gastric cancer. The concept of micro-metastasis has been described as a prognostic factor [4-9], and the biological mechanisms of LN metastasis are currently under study [10-12]. In this article, we review the status of LN metastasis including its molecular mechanisms and evaluate LN dissection for the treatment of gastric cancer.

Revisional surgery after gastrectomy for gastric cancer: review of the literature

Recent reports have shown that morbidity and mortality after gastrectomy for gastric cancer vary between authors, countries, and procedures. Common complications related to gastrectomy are postoperative bleeding, anastomotic leakage, pancreatic juice leakage, intra-abdominal abscess, intestinal obstruction, wound dehiscence, and so on. Recently, laparoscopic gastrectomy for gastric cancer has developed, especially in Japan and East Asian countries because it is less invasive. Several retrospective studies have shown that the operative complication rate is similar to that of conventional open surgery. Although most postoperative complications can be successfully treated by conservative therapies, surgical management is occasionally needed to prevent a fatal outcome. This review article provides insight into how surgeons can make efforts to reduce postoperative complications through proper preoperative evaluation and improved surgical skills during the initial gastrectomy. In addition, it reviews guidance for timely revisional surgery to allow salvage of patients with serious acute operative complications based on clinical findings made by a group of experienced surgeons.

Present and future status of gastric cancer surgery

The type of surgery and the role of adjuvant therapies in the treatment of gastric cancer have changed in recent times. The treatment of gastric cancer with curative intent is moving away from standard D2 or more extensive surgery to a tailored approach depending on the stage of the disease. Data collected from extensive lymphadenectomy for all stages of gastric cancer have confirmed that some subsets of early gastric cancer are very low risk for nodal metastasis. This group of patients may benefit from resection by endoscopic or laparoscopic techniques and may also be suitable for function-preserving procedures. The extent of resection for gastric cancer has always excited debate. D2 gastrectomy was criticized for its higher mortality in the early European Phase III trials, but recent studies from Taiwan and Italy have shown that the procedure is safe when performed by experienced surgeons and has a survival benefit over D1 gastrectomy. The role of para-aortic lymph node dissection for nodes without apparent metastasis in advanced gastric cancer was assessed by a Phase III Japanese trial and showed no additional benefit over D2 resection. Radical gastric resections, involving resection of adjacent organs for direct tumor invasion result in higher rates of complications, and the role of multi-visceral resections has also been reevaluated. Effective adjuvant therapies for gastric cancer have been reported since the early part of 2000. Development of more effective adjuvant therapy combined with D2 resection should continue to improve survival in the future.

Gastric Cancer Working Group report

EPIDEMIOLOGY

Gastric cancer is the second most common cancer in Asia, more than half of the world's gastric cancer cases arise in Eastern Asia, and the majority of Asia's cases still occur in the distal part of the stomach.

ETIOLOGY AND PREVENTION

The etiology of gastric cancer consists of genetic susceptibility, Helicobacter pylori infection and environmental risk factors. Helicobacter pylori eradication treatment, consumption of fresh vegetables and fruits and use of aspirin and non-steroidal anti-inflammatory drugs seem to reduce the risk of gastric cancer.

ENDOSCOPY AND DIAGNOSIS

Screening for gastric cancer is cost-effective in countries with high incidence. Risk stratification may increase the cost-effectiveness of screening in populations at moderate risk. Endoscopic resection is curative in a subset of patients with early cancer.

SURGERY AND ADJUVANT TREATMENT

R0 resection with D2 lymph node dissection has produced the best survival data. Some kind of post-operative adjuvant chemotherapy including S-1 is recommended after D2 surgery.

CHEMOTHERAPY FOR ADVANCED GASTRIC CANCER

As chemotherapy for gastric cancer, fluorouracils plus platinum are the most widely accepted first-line regimens, whereas taxanes or irinotecan are mostly used in second- and third-line settings. Differences in the approval and medical insurance systems may influence the status of these regimens. Trastuzumab in combination with fluorouracils/platinum will be a standard regimen for HER2-positive gastric cancer. Many new targeting agents are currently under investigation, and Asian countries are playing important roles in investigation and development of new and better treatments for this malignancy.

Large-scale investigation into dumping syndrome after gastrectomy for gastric cancer

BACKGROUND

The aim of this study was to investigate early and late dumping syndromes in a large number of patients after gastrectomy for gastric cancer.

STUDY DESIGN

Responses to questions on a visual analogue scale survey completed by 1,153 gastrectomy patients were analyzed for associations between clinical factors and occurrence of dumping syndrome. Types of gastrectomy included distal gastrectomy with Billroth I or with Roux-Y reconstruction, pylorus preserving gastrectomy, proximal gastrectomy, and total gastrectomy.

RESULTS

Based on the visual analogue scale rating of symptomatic discomfort, patients were categorized into 1 of 2 groups: symptom-free or symptomatic. Incidences of early or late dumping syndrome in all patients were 67.6% and 38.4%, respectively. Patients in whom early dumping syndrome developed were significantly more likely to experience late dumping syndrome than those in whom it did not develop (p < 0.001). According to multivariate analyses, factors that decreased the risk for developing early dumping syndrome were reduced weight loss (p < 0.01), old age (p < 0.01), pylorus preserving gastrectomy (p < 0.01), distal gastrectomy with Roux-Y reconstruction (p < 0.01), and distal gastrectomy with Billroth I (p = 0.019). In addition, factors that decreased the risk of developing late dumping syndrome were reduced weight loss (p = 0.03), being male (p < 0.01), pylorus preserving gastrectomy (p < 0.01), and distal gastrectomy with Roux-Y reconstruction (p < 0.01). No other clinical factors (lymph node dissection, vagal nerve preservation, and postoperative period) showed a substantial association with the occurrence of dumping syndrome in multivariate analyses.

CONCLUSIONS

Substantially more patients suffered from early dumping syndrome than late dumping syndrome after gastrectomy. Two clinical factors, surgical procedures and amount of body weight loss, associated significantly with the occurrence of both early and late dumping syndrome.

The role of ¹⁸F-FDG PET/CT in the assessment of suspected recurrent gastric cancer after initial surgical resection: can the results of FDG PET/CT influence patients' treatment decision making?

PURPOSE

(18)F-fluorodeoxyglucose (FDG) PET/CT has been widely used for staging, re-staging and for monitoring therapy-induced changes and response to therapy in patients with various types of cancer, but its utilization for gastric cancer has been limited. The purpose of this study was to evaluate the clinical role of FDG PET/CT in the detection of gastric cancer recurrence as compared with diagnostic CT and to assess the impact of FDG PET/CT results on patients' treatment planning.

METHODS

Thirty-four patients with suspected recurrent gastric cancer, who had previously undergone curative gastrectomy and lymph node dissection, were retrospectively analysed. The diagnostic CT and FDG PET/CT imaging were performed for all patients as clinically indicated. The results of FDG PET/CT were compared with the findings of the diagnostic CT. The changes in the clinical management of patients according to the results of FDG PET/CT were also evaluated.

RESULTS

FDG PET/CT was performed in 19 patients (55.9%) due to the suspicion of distant metastasis at diagnostic CT. The remaining 15 patients were suspected to have local recurrence at diagnostic CT (n = 4) or gastroscopy (n = 1) and due to an increase in tumour markers or clinical manifestations (n = 10). The FDG PET/CT result was positive in 23 patients (67.6%) and negative in 11 patients (32.4%). In total, 24 (70.6%) of the 34 patients had documented recurrent disease by histopathology in 7 (29.1%) and by clinical follow-up in 17 (70.9%), while 11 patients had no evidence of recurrent disease. FDG PET/CT correctly confirmed recurrent disease in 23 of the patients with recurrence and it was classified as true-positive in these patients. However, FDG PET/CT was false-negative in one patient but recurrent disease was confirmed by histopathology. The overall sensitivity, specificity, accuracy, positive and negative predictive values of FDG PET/CT were significantly superior to those of diagnostic CT (95.8 vs 62.5%, 100 vs 10%, 97 vs 47%, 100 vs 62.5% and 90.9 vs 10%, respectively, p = 0.012) in the detection of recurrent gastric cancer after initial surgery. The FDG PET/CT results changed the patients' management in 18 (52.9%) cases by leading to the use of previously unplanned treatment procedures in 9 (50%) patients and the avoidance of previously planned therapeutic procedures in 9 (50%) patients.

CONCLUSION

FDG PET/CT is a superior post-therapy surveillance modality for the diagnosis of recurrent gastric cancer compared with diagnostic CT imaging after initial surgery. In addition, integrated FDG PET/CT was specifically helpful in optimizing the treatment plan and it might play an important role in treatment stratification in the future.

Prognosis of metastatic splenic hilum lymph node in patients with gastric cancer after total gastrectomy and splenectomy

AIM

To clarify the significance of combined resection of the spleen to dissect the No. 10 lymph node (LN).

METHODS

We studied 191 patients who had undergone total gastrectomy with splenectomy, excluding non-curative cases, resection of multiple gastric cancer, and those with remnant stomach cancer. Various clinicopathological factors were evaluated for any independent contributions to No. 10 LN metastasis, using χ(2) test. Significant factors were extracted for further analysis, carried out using a logistic regression method. Furthermore, lymph node metastasis was evaluated for any independent contribution to No. 10 LN metastasis, using the same methods. The cumulative survival rate was calculated using the Kaplan-Meier method. The significance of any difference between the survival curves was determined using the Cox-Mantel test, and any difference was considered significant at the 5% level.

RESULTS

From the variables considered to be potentially associated with No. 10 LN metastasis, age, depth, invasion of lymph vessel, N factor, the number of lymph node metastasis, Stage, the number of sites, and location were found to differ significantly between those with metastasis (the Positive Group) and those without (the Negative Group). A logistic regression analysis showed that the localization and Stage were significant parameters for No. 10 LN metastasis. There was no case located on the lesser curvature in the Positive Group. The numbers of No. 2, No. 3, No. 4sa, No. 4sb, No. 4d, No. 7, and No. 11 LN metastasis were each found to differ significantly between the Positive Group and the Negative Group. A logistic regression analysis showed that No. 4sa, No. 4sb, and No. 11 LN metastasis were each a significant parameter for No. 10 LN metastasis. There was no significant difference in survival curves between the Positive Group and the Negative Group.

CONCLUSION

Splenectomy should be performed to dissect No. 10 LN for cases which have No. 4sa, No. 4sb or No. 11 LN metastasis. However, in cases where the tumor is located on the lesser curvature, splenectomy can be omitted.

Outcomes of adjuvant chemoradiotherapy after a radical gastrectomy and a D2 node dissection for gastric adenocarcinoma

PURPOSE

Intergroup 0116 (INT-0116) established adjuvant chemoradiation as the standard of care for resected high-risk adenocarcinoma of the stomach in the United States. However, adjuvant chemoradiation remains controversial in many parts of Asia and Europe, where patients tend to undergo a more thorough D2 dissection. In INT-0116, 90% of patients had a limited or inadequate node dissection (D0 or D1). Also, 17% of patients in the chemoradiation arm had to discontinue treatment because of toxicities. The objectives of this retrospective study are to report the clinical outcomes of a cohort of patients who were mostly treated with a D2 node dissection and received adjuvant chemoradiation as per INT-0116, and the toxicities of chemoradiation in the context of more aggressive surgery.

METHODS

After the results of INT-0116 became apparent, we adopted an institutional policy whereby patients who would otherwise fit the inclusion criteria of INT-0116 received adjuvant chemoradiation. Between March 1999 and November 2004, 70 consecutive patients with pathologic stage T3, T4, or node-positive disease were treated according to the chemoradiation arm of INT-0116. Patients received intravenous 5-fluorouracil 425 mg/m and leucovorin 20 mg/m in cycles 1, 3, and 4. Concurrent chemoradiation was given in cycle 2 and consisted of bolus 5-fluorouracil and leucovorin and radiotherapy (45 Gy over 25 fractions in 5 weeks). All patients were operated on by dedicated Japan-trained Surgical Oncologists.

RESULTS

Sixty-seven patients (96%) had a D2 nodal dissection. Sixty-five patients (93%) had negative pathologic margins (R0 resection) and 5 (7%) had microscopically involved margins (R1 resection). The median follow-up was 27 months (range, 10.1-60.3). The 3-year overall survival, disease-free survival, and local control were 60.6%, 54.1%, and 84.3%, respectively. Of the 30 patients who relapsed, 5 (17%) had isolated locoregional recurrences only. The National Cancer Institute--Common Terminology Criteria version 3.0 acute grade 3 or 4 gastrointestinal and hematological toxicity rates were 15.7% and 4.3%, respectively. Toxicities led to chemotherapy dose-reductions in 18 patients and dose-delay in 19 patients. Including chemotherapy dose-reductions and delays, 66 patients (94%) completed the entire chemoradiation regimen. There were no toxicity-related deaths.

CONCLUSION

In our cohort of 70 patients who had a more thorough D2 node dissection, adjuvant chemoradiation was well tolerated with acceptable toxicities and reasonable tumor control.

Clinical role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in post-operative follow up of gastric cancer: Initial results

AIM: To evaluate the clinical role of ¹⁸F-fluorodeo-xyglucose positron emission and computed tomography (¹⁸F-FDG PET/CT) in detection of gastric cancer recurrence after initial surgical resection.

METHODS: In the period from January 2007 to May 2008, 23 patients who had previous surgical resection of histopathologically diagnosed gastric cancer underwent a total of 25 ¹⁸F-FDG PET/CT scans as follow-up visits in our center. The standard of reference for tumor recurrence consisted of histopathologic confirmation or clinical follow-up information for at least 5 mo after PET/CT examinations.

RESULTS: PET/CT was positive in 14 patients (61%) and negative in 9 (39%). When correlated with final diagnosis, which was confirmed by histopathologic evidence of tumor recurrence in 8 of the 23 patients (35%) and by clinical follow-up in 15 (65%), PET/CT was true positive in 12 patients, false positive in 2, true negative in 8 and false negative in 2. Overall, the accuracy of PET/CT was 82.6%, the negative predictive value (NPV) was 77.7%, and the positive predictive value (PPV) was 85.7%. The 2 false positive PET/CT findings were actually chronic inflammatory tissue lesions. For the two patients with false negative PET/CT, the final diagnosis was recurrence of mucinous adenocarcinoma in the anastomosis in one patient and abdominal wall metastasis in the other. Importantly, PET/CT revealed true-positive findings in 11 (47.8%) patients who had negative or no definite findings by CT. PET/CT revealed extra-abdominal metastases in 7 patients and additional esophageal carcinoma in one patient. Clinical treatment decisions were changed in 7 (30.4%) patients after introducing PET/CT into their conventional post-operative follow-up program.

CONCLUSION: Whole body ¹⁸F-FDG PET/CT was highly effective in discriminating true recurrence in post-operative patients with gastric cancer and had important impacts on clinical decisions in a considerable portion of patients.

Surgery and adjuvant chemotherapy

It was clearly demonstrated that good local control by either radiotherapy or D2 surgery is essential to cure gastric cancer. D2 surgery can be carried out safely with a large volume of patients and can provide better survival than limited surgery. More extended surgery than D2 cannot provide better survival and causes greater morbidity; therefore, it should not be carried out as prophylactic lymphadenectomy. The effect of adjuvant treatment depends on the type of surgery. Neoadjuvant plus post-operative triplet chemotherapy, postoperative adjuvant chemoradiotherapy, and postoperative S-1 monotherapy now are the standards of care in Europe, the United States, and Japan, respectively.

Outcomes and survival after laparoscopic gastrectomy for adenocarcinoma. Analysis on 65 patients operated on by conventional or robot-assisted minimal access procedures

AIMS

Despite laparoscopic surgery for gastric cancer has gained worldwide acceptance, long term results and survival are seldom reported. This study was designed to assess long term outcomes after laparoscopic gastrectomy with D2 dissection. The short term results of conventional and robot-assisted minimally invasive procedures were also examined.

PATIENTS AND METHODS

The charts of 65 patients who underwent laparoscopic surgery for non-metastatic adenocarcinoma were reviewed retrospectively. This series included 35 patients with early gastric cancer (EGC) and 30 with advanced gastric cancer (AGC). A 4/5 laparoscopic subtotal gastrectomy (LSG) with D2 nodal clearance was the procedure of choice for distal cancers. Laparoscopic total gastrectomy (LTG) with modified D1 lymphadenectomy was performed for mid-proximal EGC.

RESULTS

Sixty gastrectomies were carried out laparoscopically, 56 LSG and 4 LTG. Conversion to laparotomy was required in 5 patients with distal cancer. No intraoperative complication was registered. Morbidity included 2 duodenal leaks that healed conservatively. Two postoperative deaths were registered. An average number 31.3+/-8.8 lymph nodes were collected. The mean hospital stay was 10 days (range 7-24). The mean follow up was 30 months (range 2-86) and the cumulative overall 5 year survival rate was 78%. Survival at 5 years for EGC was 94% and survival at 4 years for AGC was 53% (57% for non-converted patients).

CONCLUSIONS

Laparoscopic gastrectomy for cancer represents a valid alternative to open surgery with minimal morbidity and acceptable long term survival. Considering the risk of preoperative under diagnoses a D2 lymphadenectomy is suggested also for EGC. This study validated the effectiveness of minimally invasive technique in the management of gastric cancer.