An early gastric carcinoma treatment strategy based on analysis of lymph node metastasis

Gastric cancer with a giant lymph node metastasis: a case report and review of the literature

A 78-year-old man presented with a large abdominal mass detected by ultrasonography during a regular checkup. Even if the mass was > 10 cm in diameter, he was asymptomatic. Computed tomography detected an oval-shaped mass, with a maximum diameter of 12 cm, adjacent to the greater curvature of the stomach. Esophagogastroduodenoscopy revealed a 20 mm slightly depressed (type 0-IIc) lesion on the posterior wall of the gastric antrum, which was confirmed to be adenocarcinoma. Three cycles of combination chemotherapy with S-1 and oxaliplatin were administered as neoadjuvant chemotherapy. After neoadjuvant chemotherapy, the patient underwent distal gastrectomy, and a histopathological study identified the 12 cm giant mass as a lymph node metastasis. The postoperative course was uneventful, and thus far, the patient has completed adjuvant chemotherapy without relapse. Cases of gastric cancer with a giant lymph node metastasis are extremely rare. In this study, we report the present case and review the previous literature.

Identification of critical prognosis signature associated with lymph node metastasis of stomach adenocarcinomas

Lymph node metastasis (LNM) is an important factor affecting the prognosis of patients with gastric adenocarcinoma (STAD), which is the most common malignancy of the human digestive system. Current detection techniques have limited sensitivity and specificity, and there is a lack of effective biomarkers to screen for LNM. Therefore, it is critical to screen for biomarkers that predict LNM in STAD. Gene expression differential analysis (false discovery rate < 0.05, |log₂Fold change| ≥1.5) was performed on 102 LNM samples, 224 non-LNM samples, and 29 normal gastric tissue samples from The Cancer Genome Atlas (TCGA) STAD dataset, and 269 LNM-specific genes (DEGs) were obtained. Enrichment analysis showed that LNM-specific genes functioned mainly in cytokine-cytokine receptor interactions, calcium signaling, and other pathways. Ten DEGs significantly associated with overall survival in STAD patients were screened by multivariate Cox regression, and an LNM-based 10-mRNA prognostic signature was established (Logrank P < 0.0001). This 10-mRNA signature was well predicted in both the TCGA training set and the Gene Expression Omnibus validation dataset (GSE84437) and was associated with survival in patients with LNM or advanced-stage STAD. Using Kaplan-Meier survival, receiver operating characteristic curve, C-index analysis, and decision curve analysis, the 10-mRNA signature was found to be a more effective predictor of prognosis in STAD patients than the other two reported models (P < 0.0005). Protein-protein interaction network and gene set enrichment analysis of the 10-mRNA signature revealed that the signature may affect the expression of multiple biological pathways and related genes. Finally, the expression levels of prognostic genes in STAD tissues and cell lines were verified using qRT-PCR, Western blot, and the Human Protein Atlas database. Taken together, the prognostic signature constructed in this study may become an indicator for clinical prognostic assessment of LNM-STAD and provide a new strategy for future targeted therapy.

Current and future imaging modalities in gastric cancer

Gastric adenocarcinoma treatment can include endoscopic mucosal resection, surgery, chemotherapy, radiation, and palliative measures depending on staging. Both invasive and noninvasive staging techniques have been used to dictate the best treatment pathway. Here, we review the current imaging modalities used in gastric cancer as well as novel techniques to accurately stage and screen these patients.

Laparoscopic gastrectomy for gastric cancer: has the time come for considered it a standard procedure?

Radical gastrectomy with an adequate lymphadenectomy is the main procedure which makes it possible to cure patients with resectable gastric cancer. A number of randomized controlled trials and meta-analysis provide phase III evidence that laparoscopic gastrectomy is technically safe and that it yields better short-term outcomes than conventional open gastrectomy for early-stage gastric cancer. At present, laparoscopic gastrectomy is considered a standard procedure for early-stage gastric cancer, especially in Asian countries. On the other hand, the use of minimally invasive techniques is still controversial for the treatment of more advanced tumours, principally due to existing concerns about its oncological adequacy and capacity to carry out an adequately extended lymphadenectomy. Additional high-quality studies comparing laparoscopic gastrectomy versus open gastrectomy for gastric cancer have been recently published, in particular concerning the latest results obtained by laparoscopic approach to advanced gastric cancer. It seems very useful to update the review of literature in light of these new evidences for this subject and draw some considerations.

Patient Selection for Adjuvant Chemotherapy in High-Risk Stage II Colon Cancer: A Systematic Review and Meta-Analysis

OBJECTIVES

Patients with high-risk stage II colon cancer (CC) are recommended to undergo adjuvant chemotherapy (ACT). However, whether such patients can benefit from ACT remains unclear. This meta-analysis aimed to investigate the clinicopathologic parameters that are important for selecting patients for ACT in high-risk stage II CC.

METHODS

We systematically retrieved articles from PubMed, the Cochrane Library, and Embase that were published up to September 13, 2018. We analyzed overall survival (OS) and disease-free survival (DFS) based on hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

A total of 23 cohort studies and 1 randomized controlled trial were included in our study. Overall analyses showed that ACT improved OS (HR=0.64, 95% CI=0.51-0.80, P<0.001) and DFS (HR=0.46, 95% CI=0.28-0.76, P=0.002) in patients with high-risk stage II CC. Subgroup analyses showed that ACT improved OS in patients with localized intestinal perforation and obstruction and pT4 lesions and improved OS and DFS in patients with <12 sampled lymph nodes. However, ACT had no significant effect on OS in patients with lymphovascular invasion, perineural invasion, or poorly differentiated histology.

CONCLUSIONS

Our study suggests that not all high-risk factors (lymphovascular invasion, perineural invasion, poorly differentiated histology) show a benefit from ACT. Randomized controlled trials selectively targeting high-risk patients will need to be conducted in the future.

Prognostic nomogram based on log odds of positive lymph nodes for gastric carcinoma patients after surgical resection

Aim: To build a prognostic nomogram based on log odds of positive lymph nodes for patients with gastric carcinoma (GC) after resection, and to compare the predictive performance with the American Joint Committee on Cancer (AJCC) staging system and lymph node ratio (LNR). Methods: Multivariate analyses were performed to identify the independent variables for cancer-specific survival (CSS). A nomogram was constructed based on independent clinicopathological factors. Results: The C-indices for predicting CSS were 0.674 in development cohort and 0.647 in validation cohort, which were higher than that of the AJCC staging system and LNR. Conclusion: The nomogram was more accurate than the AJCC staging system and LNR for predicting CSS in patients undergoing resection for GC.

Usefulness of Combined PET/CT to Assess Regional Lymph Node Involvement in Gastric Cancer

Aims and Background

The aim of this study was to evaluate the value of positron emission tomography/computed tomography (PET/CT) for preoperative staging of gastric cancer and to compare the diagnostic performance of PET/CT with that of contrast-enhanced computed tomography (CECT).

Methods

We retrospectively reviewed 74 gastric cancer patients who underwent preoperative PET/CT and CECT, and subsequent curative surgical resection between April 2007 and July 2011. Preoperative PET/CT and CECT images for primary tumors of the stomach and lymph node metastases were reviewed retrospectively. The final diagnoses of primary tumors and LN metastases were based on histopathological specimens in all patients.

Results

Advanced gastric cancer was present in 65% of patients (n = 48), and the remaining patients had early gastric cancer (n = 26). Sixteen patients (22%) showed signet-ring-cell histology. For the detection of the primary tumor, the sensitivity of PET/CT was significantly higher than that of CECT (67% vs 55%, respectively; P = 0.049). For the evaluation of regional lymph node metastasis, the sensitivity, specificity, and accuracy of PET/CT and CECT were 34% and 51% (P = 0.065), 88% and 79% (P = 0.687), and 58% and 64% (P = 0.332), respectively. Neither PET/CT nor CECT detected regional lymph node metastases in early gastric cancer patients. Signet-ringcell histology showed trends of non-FDG-avid lymph node metastases (odds ratio = 0.15, 95% confidence interval 0.17–1.37, P = 0.093)

Conclusions

The accuracy of PET/CT is low and it is not a useful tool in the staging of gastric cancer overall in early gastric cancer and in signet-ring-cell carcinoma. Furthermore, the sensitivity of PET/CT could be inferior to that of CECT in the diagnosis of regional lymph node metastasis.

Surgical Resection First for Localized Gastric Adenocarcinoma: Are There Adjuvant Options?

A 55-year-old male presented with upper abdominal bloating followed by modest hematemesis that led to the diagnosis of an ulcerated poorly differentiated (with signet ring cells) adenocarcinoma in the angularis of the stomach. A contrast-enhanced positron emission tomography (PET) with computed tomography (CT) scan showed higher-than-normal physiologic avidity (standardized uptake value, 4.3) in the proximal stomach but not in the lower stomach, and the CT scan vaguely suggested a polypoid lesion in the distal stomach. Nodes were normal in size, and there were no metastases. He underwent esophagoduodenoscopy with ultrasonography (EUS) that showed a 3- x 2-cm flat nodular mass with an 8-mm ulcer in the angularis. The tumor mass was demarcated well on narrow-band imaging, and with a 20-MHz EUS probe, it was designated eusT1bN0. His case was presented to our weekly Multidisciplinary Gastric Adenocarcinoma Conference, and the consensus was to offer surgery as primary therapy. He underwent a subtotal gastrectomy with Roux-en-Y gastrojejunostomy along with D2 nodal dissection. The surgical pathology showed a poorly differentiated adenocarcinoma with signet ring cells; the primary tumor measured 2.8 x 2.2 cm in diameter with infiltration through the muscularis propria and into the subserosal fat. Seven of 53 examined lymph nodes were malignant; therefore, his cancer was staged pT3N3M0 (a higher stage than designated clinically). He recovered well without complications, and the postoperative CT scans showed no metastases. His case was represented at the tumor board meeting, and adjuvant chemotherapy with oxaliplatin and capecitabine was recommended.

A New Statistical Model Identified Two-thirds of Clinical T1 Gastric Cancers as Possible Candidates for Endoscopic Treatment

BACKGROUND

Clinical T1 gastric cancer has low metastatic potential to lymph nodes and is generally curable by local treatment. Endoscopic resection can preserve the whole stomach and does not impair the patient's quality of life; however, its indication is strictly limited to the subset of patients without nodal metastasis. The study was designed to predict reliably the patients without nodal metastasis based only on the clinical information.

METHODS

We examined patients with clinical T1 disease who were treated with surgery. The clinically available information was evaluated for its ability to predict nodal metastasis by logistic regression model. Then, the predictive ability of the logistic regression model using the risk factors for nodal metastasis was evaluated by a receiver operating characteristic curve.

RESULTS

A total of 511 patients were entered into this study. The clinical depth (cT1a or cT1b), maximal tumor diameter, and pathological type were confirmed to be significantly different between patients with and without nodal metastasis. The cutoff value of the tumor diameter differed depending on the histology and clinical depth: 79 mm for differentiated type and 48 mm for undifferentiated type in cT1a tumors, and 43 mm for differentiated type and 11 mm for undifferentiated type in cT1b tumors. According to these criteria, 348 of the 511 patients (68.1 %) were classified to have predictive N0 status. The negative predictive value was 95.7 % (95 % confidence interval 94.0-97.5 %).

CONCLUSIONS

The predictive criteria based on the multivariate logistic model identified that almost two-thirds of the patients with clinical T1 gastric cancer were possible candidates for endoscopic treatment.

Diagnostic accuracy of endoscopic ultrasonography (EUS) for the preoperative locoregional staging of primary gastric cancer

BACKGROUND

Endoscopic ultrasound (EUS) is proposed as an accurate diagnostic device for the locoregional staging of gastric cancer, which is crucial to developing a correct therapeutic strategy and ultimately to providing patients with the best chance of cure. However, despite a number of studies addressing this issue, there is no consensus on the role of EUS in routine clinical practice.

OBJECTIVES

To provide both a comprehensive overview and a quantitative analysis of the published data regarding the ability of EUS to preoperatively define the locoregional disease spread (i.e., primary tumor depth (T-stage) and regional lymph node status (N-stage)) in people with primary gastric carcinoma.

SEARCH METHODS

We performed a systematic search to identify articles that examined the diagnostic accuracy of EUS (the index test) in the evaluation of primary gastric cancer depth of invasion (T-stage, according to the AJCC/UICC TNM staging system categories T1, T2, T3 and T4) and regional lymph node status (N-stage, disease-free (N0) versus metastatic (N+)) using histopathology as the reference standard. To this end, we searched the following databases: the Cochrane Library (the Cochrane Central Register of Controlled Trials (CENTRAL)), MEDLINE, EMBASE, NIHR Prospero Register, MEDION, Aggressive Research Intelligence Facility (ARIF), ClinicalTrials.gov, Current Controlled Trials MetaRegister, and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), from 1988 to January 2015.

SELECTION CRITERIA

We included studies that met the following main inclusion criteria: 1) a minimum sample size of 10 patients with histologically-proven primary carcinoma of the stomach (target condition); 2) comparison of EUS (index test) with pathology evaluation (reference standard) in terms of primary tumor (T-stage) and regional lymph nodes (N-stage). We excluded reports with possible overlap with the selected studies.

DATA COLLECTION AND ANALYSIS

For each study, two review authors extracted a standard set of data, using a dedicated data extraction form. We assessed data quality using a standard procedure according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria. We performed diagnostic accuracy meta-analysis using the hierarchical bivariate method.

MAIN RESULTS

We identified 66 articles (published between 1988 and 2012) that were eligible according to the inclusion criteria. We collected the data on 7747 patients with gastric cancer who were staged with EUS. Overall the quality of the included studies was good: in particular, only five studies presented a high risk of index test interpretation bias and two studies presented a high risk of selection bias.For primary tumor (T) stage, results were stratified according to the depth of invasion of the gastric wall. The meta-analysis of 50 studies (n = 4397) showed that the summary sensitivity and specificity of EUS in discriminating T1 to T2 (superficial) versus T3 to T4 (advanced) gastric carcinomas were 0.86 (95% confidence interval (CI) 0.81 to 0.90) and 0.90 (95% CI 0.87 to 0.93) respectively. For the diagnostic capacity of EUS to distinguish T1 (early gastric cancer, EGC) versus T2 (muscle-infiltrating) tumors, the meta-analysis of 46 studies (n = 2742) showed that the summary sensitivity and specificity were 0.85 (95% CI 0.78 to 0.91) and 0.90 (95% CI 0.85 to 0.93) respectively. When we addressed the capacity of EUS to distinguish between T1a (mucosal) versus T1b (submucosal) cancers the meta-analysis of 20 studies (n = 3321) showed that the summary sensitivity and specificity were 0.87 (95% CI 0.81 to 0.92) and 0.75 (95% CI 0.62 to 0.84) respectively. Finally, for the metastatic involvement of lymph nodes (N-stage), the meta-analysis of 44 studies (n = 3573) showed that the summary sensitivity and specificity were 0.83 (95% CI 0.79 to 0.87) and 0.67 (95% CI 0.61 to 0.72), respectively.Overall, as demonstrated also by the Bayesian nomograms, which enable readers to calculate post-test probabilities for any target condition prevalence, the EUS accuracy can be considered clinically useful to guide physicians in the locoregional staging of people with gastric cancer. However, it should be noted that between-study heterogeneity was not negligible: unfortunately, we could not identify any consistent source of the observed heterogeneity. Therefore, all accuracy measures reported in the present work and summarizing the available evidence should be interpreted cautiously. Moreover, we must emphasize that the analysis of positive and negative likelihood values revealed that EUS diagnostic performance cannot be considered optimal either for disease confirmation or for exclusion, especially for the ability of EUS to distinguish T1a (mucosal) versus T1b (submucosal) cancers and positive versus negative lymph node status.

AUTHORS' CONCLUSIONS

By analyzing the data from the largest series ever considered, we found that the diagnostic accuracy of EUS might be considered clinically useful to guide physicians in the locoregional staging of people with gastric carcinoma. However, the heterogeneity of the results warrants special caution, as well as further investigation for the identification of factors influencing the outcome of this diagnostic tool. Moreover, physicians should be warned that EUS performance is lower in diagnosing superficial tumors (T1a versus T1b) and lymph node status (positive versus negative). Overall, we observed large heterogeneity and its source needs to be understood before any definitive conclusion can be drawn about the use of EUS can be proposed in routine clinical settings.

Usefulness of three-dimensional angiographic analysis of perigastric vessels before laparoscopic gastrectomy

BACKGROUND

Recognition of perigastric vessel anatomy is important to safely perform gastric surgery, especially in the case of laparoscopic gastrectomy. This study was designed to reevaluate the efficacy of preoperative three-dimensional (3D) angiography reconstructed from enhanced multidetector-row computed tomography (MDCT) data and to classify right gastric artery (RGA) branching patterns.

METHODS

Perigastric vessel anatomy was preoperatively analyzed using MDCT-based 3D angiography reconstructed by computer software in patients undergoing laparotomic (n = 75) and laparoscopic (n = 25) gastrectomy. Results were compared with intraoperative findings in all cases, and were also compared with maximum intensity projection (MIP) imaging, which is similar to conventional angiography, in 10 patients.

RESULTS

Preoperative diagnoses by 3D angiography were identical to intraoperative findings. The rates of branching patterns of the celiac artery and left gastric vein were comparable with previous reports. The detection rate of the right gastric artery (RGA) was 77.0%. Branching patterns of the hepatic artery were classified into four types: right hepatic artery (RHA) + left hepatic artery (LHA) type, replaced RHA + LHA type, RHA + replaced LHA type, and replaced RHA + replaced LHA type. RGA ramification patterns were classified into three types according to hepatic arterial running patterns: distal (68.8%), proximal (14.3%), and caudal (16.9%). Because of vessel overlapping, RGA ramified points were misdiagnosed under MIP images in two of ten cases (20%).

CONCLUSIONS

Preoperative 3D angiography is useful for a new system of classifying RGA ramification patterns into three types. With this system, surgeons can perform laparoscopic gastrectomy with lymph node dissection more safely.

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.

Treatment strategy for early gastric cancer

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

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.

Trends in characteristics of surgically treated early gastric cancer patients after the introduction of gastric cancer treatment guidelines in Japan

BACKGROUND

The gastric cancer treatment guidelines (Guidelines) of the Japanese Gastric Cancer Association allow endoscopic treatment and a modified gastrectomy for the treatment of early gastric cancer (EGC). Endoscopic treatment is indicated for EGC with a minimal chance of nodal metastasis. Consequently, surgeons will likely treat an increasing number of EGC patients with greater chance of nodal metastasis using a reduced extent of lymphadenectomy. The aim of this study was to investigate the trends in characteristics and long-term oncological outcomes of surgically treated EGC patients after the introduction of the Guidelines.

METHODS

Between 2001 and 2003, 696 patients underwent a gastrectomy according to the Guidelines. These 696 patients (the Guidelines group) were retrospectively compared with 635 patients (the control group) who had undergone a gastrectomy between 1991 and 1995 (before the introduction of the Guidelines).

RESULTS

The incidence of nodal metastasis in mucosal cancers was higher in the Guidelines group than in the control group (6.5% vs 2.6%). The proportion of D2 or greater extended lymphadenectomy in the Guidelines group was lower than that in the control group (29.7% vs 62.5%). Nevertheless, the 5-year survival rate in the Guidelines group was similar to that in the control group (94.2% vs 92.3%).

CONCLUSION

Surgeons treated more cases of mucosal cancer with nodal metastasis after the introduction of the Guidelines. The long-term oncological outcomes for patients with EGC remained excellent. So far, the Guidelines for the treatment of EGC appear acceptable.

Pattern of lymph node involvement in proximal gastric cancer

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Comparison of long-term outcomes of laparoscopy-assisted and open distal gastrectomy for early gastric cancer

BACKGROUND

Application of laparoscopy-assisted distal gastrectomy (LADG) for early gastric cancer (EGC) is still controversial because of scant evidence of long-term safety and feasibility. We evaluated the long-term outcome of LADG compared with conventional open distal gastrectomy (ODG) for EGC.

METHODS

Between March 1999 and July 2006, 106 patients underwent LADG and 105 patients underwent ODG for EGC. Clinicopathologic characteristics, postoperative outcomes, hospital course, postoperative morbidity, postoperative mortality, and long-term outcomes, including cancer recurrence and survival, were retrospectively compared between the two groups. Survival of all patients was confirmed with 55-month median follow-up.

RESULTS

Postoperative recovery was significantly faster in the LADG group; passing flatus occurred earlier, starting a liquid diet began sooner, and postoperative hospital stay was shorter (p < 0.05). Mean operation time was significantly longer in the LADG group. Postoperative complications in the LADG group occurred less frequently compared with in the ODG group (4.7% versus 13.3%, p = 0.046). Tumor recurrence occurred in two cases (0.9%) and death related to recurrence occurred in only one patient (0.5%). Overall 5-year survival rate (5-YSR) of all patients was 95.5%, while disease-specific 5-YSR was 98.8%. There was no significant difference in survival rates between the two groups; overall 5-YSR of the ODG and LADG groups was 94.9% and 95.9%, respectively.

CONCLUSIONS

Our data suggest that LADG for EGC is feasible and safe. We expect the results of the present study to be confirmed by prospective randomized analysis.

Risk factors associated with local recurrence of early gastric cancers after endoscopic submucosal dissection

BACKGROUND

Although endoscopic submucosal dissection (ESD) is expected to reduce the local recurrence of gastric cancers, we still experience cases of recurrence after an ESD.

OBJECTIVE

To characterize clinical and pathologic features of cases with local recurrence of early gastric cancer after an ESD.

DESIGN

A prospective cohort study.

SETTING AND PATIENTS

A total of 306 patients with gastric cancers removed by ESD at Okayama University Hospital and Tsuyama Central Hospital between March 2001 and December 2005 were enrolled.

INTERVENTION

ESD.

MAIN OUTCOME MEASUREMENT

Local recurrence.

RESULTS

The incidence of a complete en bloc resection was 80.4% when pathologically evaluated. Within a median follow-up period of 26 months (12-64 months), a local recurrence was found in 7 cases, all of which had been declared incomplete resections. One patient underwent a second ESD, and the remaining 6 underwent a surgical resection. All removed lesions were mucosal cancers. No lymph-node metastases were found in patients with a surgical resection. There was a significant correlation between the incidence of an incomplete resection and that of a local recurrence (P < .0001). Among the clinical characteristics, tumor size (>30 mm vs <20 mm; odds ratio [OR] 16 mm [95% CI, 2.0-130 mm]) and tumor location (upper vs middle or lower; OR 7.6 [95% CI, 1.3-45]) were identified as factors that were significantly associated with the incidence of a local recurrence.

LIMITATION

Short follow-up duration.

CONCLUSIONS

The incidence of a local recurrence was strongly associated with that of an incomplete resection. The frequency of a local recurrence also showed significant correlations with the tumor size and location within the stomach.

Current status of minimal access surgery for gastric cancer

BACKGROUND

The aim was to conduct a systematic review of the literature on the subject of laparoscopic gastrectomy (LG) and determine the relative merits of laparoscopic (LG) and open gastrectomy (OG) for gastric carcinoma.

MATERIAL AND METHODS

A search of the Medline, Embase, Science Citation Index, Current Contents and PubMed databases identified individual retrospective and prospective series on LG (proximal, distal and total). Furthermore, all clinical trials that compared LG and OG published in the English language between January 1990 and the end of December 2006 were also identified. A large number of outcome variables were analysed for individual series and comparative trials between LG and OG and results discussed and tabulated.

RESULTS

The majority of the literature is published from Japan showing both oncological adequacy and safety of LG. The majority of early series and comparative studies have utilized laparoscopic resection for early and distal gastric cancer. However, with increasing advanced laparoscopic experience, advancement in digital technology and improvement in instrumentation, more advanced gastric cancers and more extensive procedures such as laparoscopic-assisted total gastrectomy and laparoscopy-assisted D2 dissection are becoming more common. To date lymph node harvesting, resection margins and complication rates seem to be equivalent to open procedures. Furthermore, the earlier fears of port-site metastases have not been borne out.

CONCLUSIONS

The available data suggests that LG seems to be associated with quicker return of gastrointestinal function, faster ambulation, earlier discharge from hospital, and comparable complications and recurrence rate to OG. However, the operating time for LG remains significantly longer compared to its open counterpart, although with experience it is achieving parity with OG. However, the majority of the comparative trials (if not all) probably do not have the power to detect differences in the outcome. As far as the RCT's (LG vs. OG) are concerned, the numbers of patients in such trials are small and the majority of patients were operated upon for early distal gastric cancer and, therefore, any meaningful conclusions regarding the advantages or disadvantages of LG for both the ECGs and extensive and advanced gastric tumours are difficult to justify.

The role of surgery after incomplete endoscopic mucosal resection for early gastric cancer

PURPOSE

Endoscopic mucosal resection (EMR) is a relatively new treatment option for early gastric cancer (EGC). However, cases of incomplete EMR resulting in a positive lateral margin or submucosal invasion (positive vertical margin) have been reported. We conducted this study to evaluate the role of surgery after incomplete EMR for EGC.

METHODS

We analyzed 19 patients who underwent gastrectomy as a result of an incomplete EMR. The patients were divided into three groups according to the type of incomplete EMR: a positive lateral margin (LM) group (n = 9), a positive vertical margin (VM) group (n = 4), and a positive lateral and vertical margin (LM + VM) group (n = 6).

RESULTS

The positive residual tumor rate and the positive lymph node rate were 44.4% (4/9) and 0% (0/9) in the LM group, 50.0% (2/4) and 25.0% (1/4) in the VM group, and 83.3% (5/6) and 16.7% (1/6), LM + VM group, respectively. Curative resection was performed in all patients and there was no recurrence in 30.8 months of follow-up.

CONCLUSION

Radical surgery is recommended for patients with a positive lateral resection margin or submucosal invasion, or both, after EMR for EGC, because of the possibility of residual tumor or lymph node metastasis.

Laparoscopic gastrectomy with lymph node dissection for gastric cancer

Since 1991, laparoscopic surgery has been adopted for the treatment of gastric cancer, and it has been performed worldwide, especially in Japan and Korea. We reviewed the English-language literature to clarify the current status of and problems associated with laparoscopic gastrectomy with lymph node dissection as treatment for gastric cancer. In Japan, early-stage gastric cancer (T1/T2, N0) is considered the only indication for laparoscopic gastrectomy. As yet, there is little high-level evidence based on long-term outcome supporting laparoscopic gastrectomy for cancer, but reports have provided level 3 evidence that the procedure is technically safe, and that it yields better short-term outcomes than open surgery; that is, recovery is faster, hospital stay is shorter, there is less pain, and cosmesis is better. However, investigation into the oncological outcome of laparoscopic gastrectomy as treatment for cancer is lacking. To establish laparoscopic surgery as a standard treatment for gastric cancer, multicenter randomized controlled trials to compare the short- and long-term outcomes of laparoscopic surgery versus open surgery are necessary.

Surgical results of early gastric cancer and proposing a treatment strategy

BACKGROUND

Prognosis for patients with early gastric cancer after surgical resection is excellent. The 5-year or even 10-year survival is more than 90%. In the present study, we investigated the result of treating early gastric cancer surgically in our hospital, with special reference to the risk factor(s) for tumor recurrence and the relationship between age and survival.

PATIENTS AND METHODS

From January 1988 to December 2002, a total of 479 patients with early gastric cancer underwent resection by our surgeons. Results of preoperative studies, operative findings, histopathology and postoperative follow-up were recorded respectively, and the postoperative disease-related survival, overall survival, tumor recurrence and recurrent patterns were analyzed. The clinicopathological factors were also analyzed to identify the risk factor(s) related to tumor recurrence.

RESULTS

Older patients (>75 years old) had a poorer overall survival than younger patients. However, the disease-related survival was not significantly different between the two. Recurrence was observed in 21 patients, the most important factor of which was lymph node status. Lymph node metastases occurred in 54 patients (11.3%)-coming from mucosal tumors in 12 patients (4.4%) and from submucosal tumors in 42 (20.3%). When the size of the mucosal tumor was smaller than 1 cm, no lymph node metastasis was found in our patients.

CONCLUSIONS

The most important risk factor of recurrence in early gastric cancer is lymph node status. Given the low probability of lymph node metastasis and recurrence in tumors less than 1 cm in diameter limited to the mucosa, more limited surgery maybe appropriate in these carefully selected instances.

EUS staging of upper GI malignancies: results of a prospective randomized trial

BACKGROUND

Electronic 270 degrees transverse-array EUS (TA-EUS) provides high-quality cross-sectional images but cannot guide FNA. Linear EUS (L-EUS) provides longitudinal images of malignancies and the ability to guide FNA.

OBJECTIVE

We conducted a prospective randomized comparison of TA-EUS and L-EUS for the staging of upper-GI (UGI) malignancies.

DESIGN

Forty-three patients underwent L-EUS immediately followed by TA-EUS (N = 27, 63%) or TA-EUS immediately followed by L-EUS (N = 16, 37%).

PATIENTS

Forty-three subjects (mean age, 64 years; 37 men) with an UGI malignancy (4 stomach and 38 esophageal) were evaluated with both TA-EUS and L-EUS.

INTERVENTIONS

Abnormal lymph nodes were sampled by FNA for cytology.

RESULTS

There was agreement on the T stage by linear and radial techniques in 38 of 43 subjects (88%). Twenty-seven of 43 patients (63%) had abnormal lymph nodes by linear or transverse-array imaging. L-EUS demonstrated 66 abnormal lymph nodes in 27 subjects (average of 2.4 nodes/subject). TA-EUS demonstrated 90 abnormal lymph nodes in 27 subjects (average of 3.3 nodes/subject, P = .009, compared with L-EUS). In 16 of the 27 subjects, an FNA was performed, which was positive in 13 cases (81%) and negative in 3 cases (10%) for malignancy.

CONCLUSIONS

TA-EUS and L-EUS provide similar results of T staging of UGI malignancies. However, the number of abnormal lymph nodes detected by TA-EUS was more than by L-EUS. These findings suggest that radial or transverse-array EUS imaging should be the primary method for staging of UGI malignancies.

Number of lymph node metastases and its prognostic significance in early gastric cancer: a multicenter Italian study

BACKGROUND AND OBJECTIVES

This study was aimed at evaluating the prognostic significance of the number of metastatic nodes in early gastric cancer (EGC).

METHODS

In this multicenter retrospective study 652 cases of resected EGC were analyzed. We searched for lymph node metastases-associated risk factors and to identify subsets of patients with different prognosis according to the number of involved nodes.

RESULTS

Nodal involvement was observed in 14.1%. A significant correlation was found between the presence of node metastases and tumor size (RR 1.34, P = 0.001), submucosal invasion (RR: 3.14, P = 0.007), Lauren diffuse/mixed type (RR: 4.88, P < 0.001) and Kodama Pen A type (RR: 4.59, P < 0.001). The 10-year survival rate was 92% for N0 cases, 82% and 73% for tumors with one to three and four to six positive nodes while it dropped to 27% with more than six metastatic nodes. Interestingly enough, the 10-year risk of recurrence diminished with the increasing number of retrieved nodes (>15) even in N0 patients.

CONCLUSIONS

Nodal involvement confirmed to be a significant prognostic factor. In view of the trend to a lower risk of recurrence when more than 15 nodes were retrieved and the better staging achieved we consider D2 lymphadenectomy the treatment of choice.

Grasping forceps-assisted endoscopic mucosal resection of early gastric cancer with a novel 2-channel prelooped hood

BACKGROUND

Endoscopic mucosal resection with a cap-fitted panendoscope (EMRC) such as a soft prelooped hood is a useful, effective, and safe technique. One problem with this method is that the lesion cannot always be maintained in the center of the cap because the procedure is performed blindly after aspiration.

OBJECTIVE

We developed a 2-channel prelooped hood that facilitates EMRC while simultaneously allowing both grip of the center in the lesion and irrigation of the aspiration site and evaluated the usefulness of this end hood for early gastric cancer.

DESIGN

Retrospective study.

SETTING

Between August 2003 and October 2004, patients underwent our novel EMR.

PATIENTS

Twelve cases of early gastric cancer.

INTERVENTIONS

Two side holes were fabricated by drilling in the cap portion of a conventional soft prelooped hood, and then the irrigation tube and the accessory channel tube were glued to the exterior surface of the holes. We placed the fabricated transparent hood at the tip of the endoscope and performed grasping forceps-assisted endoscopic aspiration mucosectomy.

MAIN OUTCOME MEASUREMENTS

Accurate aspiration and the rate of en bloc resection.

RESULTS

We obtained a satisfactory field of view and accurate aspiration in the center of the tumor in all lesions. The rate of en bloc resection was 91.7% (11/12).

LIMITATIONS

Gastric intramucosal cancer.

CONCLUSION

Grasping forceps-assisted endoscopic mucosal resection with a novel 2-channel prelooped hood is safe and useful for mucosal resection of intramucosal cancers less than 20 mm and may help center the lesion in the cap before resection.

Endoscopic mucosal resection

Endoscopic mucosal resection (EMR) is a promising therapeutic option for removal of superficial carcinomas or premalignant lesions throughout the gastrointestinal tract. This review discusses indications and the several techniques of EMR in early tumors of esophagus, stomach, duodenum, and colon. EMR is not yet widely utilized in the West. However, great benefits may be obtained from this non-invasive technique after an accurate evaluation of patients and a careful staging of lesions that may assess the depth of infiltration and exclude the presence of lymph node metastases. EMR permits a complete removal of the lesion with histologic assessment of the entire specimen and the change in the pathologic stage in a significant number of patients. To minimize the risk of serious complications (mostly bleeding and perforation), only experienced endoscopists should undertake EMR in an appropriate environment. Data from literature are encouraging on the use of EMR, but a long-term follow-up of a large number of patients is necessary to confirm the effectiveness of this therapy.

Assessment of lymph node metastases using 18F-FDG PET in patients with advanced gastric cancer

PURPOSE

The aim of this study was to assess the diagnostic accuracy of (18)F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) with respect to lymph node (LN) metastasis in patients with advanced gastric cancer, and to ascertain the factors that affect this accuracy.

METHODS

Seventy-three patients with advanced gastric cancer, verified in all cases by endoscopic biopsy, were enrolled in this prospective study. We conducted FDG PET and other routine preoperative studies, including abdominal computed tomography (CT). Patients underwent either curative-intent gastrectomy and lymphadenectomy (n = 67) or exploratory laparotomy. The Japanese system for the classification of gastric cancer was used for LN assessment.

RESULTS

FDG PET was able to detect primary lesions in 70 of the 73 cases. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value of FDG PET for LN metastasis were 40%, 95%, 91% and 56%, respectively. Signet-ring cell carcinoma was associated with the lowest sensitivity (15%), whereas other cell types could be detected with moderate sensitivity (30-71%) and high specificity (93-100%). According to multiple logistic regression, the standardised uptake value for primary tumours was the only independent variable to be significantly related to sensitivity for LN metastasis (p = 0.02, odds ratio = 1.14). CT was superior to PET in terms of sensitivity (p < 0.0001), and PET was superior to CT in terms of specificity (p < 0.0001) and PPV (p = 0.05).

CONCLUSION

FDG PET exhibits good specificity for LN staging of gastric cancer, and FDG uptake in the primary tumour is significantly related to the accuracy of FDG PET. Despite some clear limitations, FDG PET proved useful in the LN staging of FDG-avid gastric cancer.

Gastric cancer

Gastric cancer is one of the most common cancers and one of the most frequent causes of cancer-related deaths. The incidence, diagnostic studies, and therapeutic options have undergone important changes in the last decades, but the prognosis for gastric cancer patients remains poor, especially in more advanced stages. Surgery is the mainstay of treatment of this disease, even if it is associated with a high rate of locoregional and distant recurrence. There is ongoing debate regarding the role of adjuvant treatment In advanced disease, palliation of symptoms, rather than cure, is the primary goal of patient management. Several combination therapies have been developed and have been examined in phase III trials; however, in most cases, they have failed to demonstrate a survival advantage over the reference arm. This review summarizes the most important recommendations for the management of patients with gastric cancer.

Minimally invasive treatment for gastric cancer: approaches and selection process

Minimally invasive treatment of gastric cancer has emerged as a result of the technical advances, better understanding of gastric physiology, and more knowledge of the biologic behavior of gastric cancer. This treatment results in improved quality of life embodied by smaller incisions, reduced length of hospital stay, and a faster return to productive life. However, minimally invasive treatment for gastric cancer must take into consideration the potential effects of these techniques on tumor dissemination at the time of the treatment procedure, as well as the rates of recurrence and overall survival. Several technical treatment approaches to gastric cancer have now become possible, utilizing endoscopy, laparoscopy, or an open method. Endoscopic mucosal resection (EMR), limited resection, and laparoscopic surgical resection are the currently practiced modalities as the minimally invasive treatment. Lymph node dissection with the minimally invasive techniques is a barrier to its wide application. Although it is not commonly performed in Western countries, the use of minimally invasive treatment for gastric cancer is growing, especially in Korea and Japan. Minimally invasive treatment for early gastric cancer (EGC) has already been shown to be safe and effective in many retrospective series though no prospective randomized studies comparing it to open resection have been performed. Therefore, routine implementation of these procedures must await confirmatory outcomes generated by well-done randomized prospective clinical trials.

Minimally Invasive Treatment of Stomach Cancer

The rate of detection of early gastric cancer has increased because of the development of diagnostic techniques, such as endoscopy, biopsy, and endoscopic ultrasonography. Recently, minimally invasive surgical procedures for benign gastric conditions have been advocated, and the laparoscopic approach is noted as a technique that increases the quality of life. However, the development of laparoscopic gastric resections and laparoscopically assisted gastric operations for malignancy still deserve a word of caution. Laparoscopic local resection of the stomach is used to treat mucosal cancer without lymph node metastasis, and laparoscopy-assisted distal gastrectomy is used to treat early gastric cancer with lymph node metastasis in the perigastric portion. According to short-term results reported by a small group of surgeons, laparoscopic approaches for gastric cancer result in a minimally invasive approach, early recovery, and decreased morbidity and mortality. However, the longterm results of these less invasive treatments are not known in advanced gastric cancer. If the results of randomized controlled studies for advanced gastric cancer are confirmed, the use of these techniques will spread worldwide and may become a standard technique for the resection of gastric cancer.

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.

Circulating level of hepatocyte growth factor as a useful tumor marker in patients with early-stage gastric carcinoma

BACKGROUND

Although conventional tumor markers including carcinoembryonic antigen (CEA) and carbohydrate antigen (CA19-9) have been used in gastric cancer patients, clinically useful markers of early gastric cancer have not been identified. The present study was designed to clarify the clinical significance of the circulating level of hepatocyte growth factor (HGF) as a tumor marker, especially in early-stage gastric cancer patients.

METHODS

Preoperative serum HGF levels were measured with an enzyme-linked immunosorbent assay in 30 early-stage and 42 advanced-stage gastric cancer patients.

RESULTS

The mean value of serum HGF in 72 patients was significantly higher than that in the normal subjects. There was a significant increase in serum HGF levels in both advanced-stage and early-stage patients compared with normal subjects. The positivity rates of HGF in early disease cases were higher than those of CEA and CA19-9. The serum HGF level was significantly higher in patients with vessel invasion than in those without invasion. In smaller early gastric cancers, serum HGF elevation was associated with lymphatic invasion.

CONCLUSIONS

The serum HGF level may be a clinically significant tumor marker in patients with early-stage, as well as advanced-stage, gastric cancer. HGF elevation in early-stage patients may help us to predict the risk of lymph node metastasis of early gastric tumors, even of smaller tumor size. HGF may be a useful indicator for appropriate lymphadenectomy in early gastric cancer.

EMR of upper GI lesions when using a novel soft, irrigation, prelooped hood

BACKGROUND

EMR with a cap-fitted endoscope, including a soft, prelooped hood, is a useful, effective, and safe technique. One problem with this method, however, is that the lesion cannot always be kept in the center of the cap because the procedure is performed blindly after aspiration. A soft, prelooped hood with attached irrigation tube was developed. The usefulness of this device for EMR of upper-GI intramucosal cancers was evaluated.

METHODS

The end-hood piece was fabricated by drilling a side hole in the cap portion of a conventional soft, prelooped hood and then attaching an irrigation tube with glue to the exterior surface of the hole. The fabricated transparent hood was placed at the tip of an endoscope, and aspiration mucosectomy under irrigation was performed in 15 patients with upper-GI intramucosal cancer. When the field of view at the aspiration site was obscured by oozing blood, the site was irrigated.

RESULTS

A satisfactory view was obtained of all lesions. The mean diameter of specimens was 24.5 mm (interquartile range: 15-35). The proportion of en bloc resected lesions was 86.7% (13/15). Bleeding was the only complication (4/15; 26.7%) and was controlled by using endoscopic hemostatic techniques under irrigation.

CONCLUSIONS

EMR when using the soft, prelooped hood with irrigation tube is effective and safe for intramucosal cancers 20 mm or less in diameter.

Survival after surgical treatment of early gastric cancer, surgical techniques, and long-term survival

Early gastric cancer (EGC) is well accepted as having a favorable prognosis after surgical treatment. Difference in treatment strategies for EGC between Japan and western countries indicates a need for current information to be evaluated with regard to long-term survival rates of EGC patients throughout the world. To analyze survival rates and recurrence after resection of EGC, we investigated 51 reports in English that each included more than 50 cases of EGC treated by gastrectomy and had been published during the past 12 years (1992-2003). Prevalence of EGC among all gastric cancers was 45%-51% in Japan, but only 7%-28% in western countries. Mean age at diagnosis was less than 60 years in Japan and Korea, but was more than 60 in most of the Western countries. Actuarial and disease-specific 5-year survival rates for EGC were 72%-95.8% and 88%-98.3%, respectively. Those for EGC that were invading the submucosal layer were 71.6%-94.1% and 82%-96.6%, respectively. Those for EGC with lymph node metastasis were 57%-89.1% and 72%-93.5%, respectively. Prevalence of recurrence ranged from 1.0% to 13.8%. Larger clinical series with more EGC cases showed a lower prevalence of recurrence (P=0.531, P=0.0026). Liver and blood-borne distant metastasis represented the predominant pattern of relapse, accounting for over half (54%). Local recurrence and peritoneal dissemination represented 20% and 18% of all recurrences, respectively. Clinicopathological studies have shown lymph node metastasis to be closely related to depth of invasion, size of lesion, histological type, presence of ulcer or ulcer scar, and vessel involvement. Information on these factors is the key to successful treatment of EGC. When sufficient information has been assessed preoperatively, surgeons can select patients for whom less-invasive surgery should not increase the risk of recurrence.

Gastric Adenocarcinoma

Adenocarcinoma of the stomach is advanced enough in some patients to preclude curative treatment, but many gastric cancer patients have what appears to be localized disease that is amenable to surgical resection, which is the only truly effective treatment. Long-term results of what appear to be "curative resections" are relatively poor, however, and new management tools such as sentinel lymph node biopsy, recently promising adjunctive therapies (such as radiochemotherapy), and the organization of the order of treatment combinations do require further study with an eye to improving outcomes. However, there appears to be little hope for a dramatic improvement in treatment results from these innovations for patients with established gastric cancer. Fortunately, gastric cancer in the United States has gone from being the number one cause of cancer death in our population 50 years ago to that of being the number eight cause of cancer death at this time. This intriguing major decrease in the incidence of this disease must be considered secondary to one or more changes in our own environment that we hope will be exploitable in the future. As with cancers of all types and in all sites, a prevention strategy may prove more effective than the treatment strategies that are outlined here. The management strategies outlined are hopefully only temporary ones until we are able to develop a better handle on primary prevention.

Preoperative simulation of vascular anatomy by three-dimensional computed tomography imaging in laparoscopic gastric cancer surgery

BACKGROUND

Treatment of early gastric cancer may be an ideal application for laparoscopic surgery. But laparoscopic surgery has various limitations derived from the lack of tactile feedback and a two-dimensional display of the operative field. So, laparoscopic surgery is technically challenging and requires a more detailed understanding of local anatomy than conventional open surgery does. The purpose of this study was to evaluate the value of three-dimensional computed tomography imaging in the preoperative simulation of laparoscopic gastric cancer surgery.

STUDY DESIGN

Multidetector-row helical CT was performed preoperatively in 49 patients who underwent laparoscopic gastric cancer surgery. Scanning was initiated approximately 20 seconds after an intravenous injection of 100 mL of contrast material at 5 mL/second. Three-dimensional CT images were reconstructed using the volume-rendering technique.

RESULTS

3D-CT imaging depicted the stomach, arterial, and venous anatomy and was able to identify important vascular variants. Preoperative information concerning the right gastric artery led us to the site of its branching and facilitated dissection of suprapyloric lymph nodes. The left gastric artery furnishing the aberrant left hepatic artery was successfully revealed and this information enabled us to avoid accidental hemorrhage and ischemic liver damage. Preoperative confirmation of the drainage routes of the left gastric vein was also useful in accomplishing secure lymphadenectomy.

CONCLUSIONS

3D-CT imaging provides a vascular "road map," which is critical for surgical guidance, and prevents the risks involved in surgery. Preoperative 3D-CT imaging may be an informative device to overcome the disadvantages of laparoscopic gastric cancer surgery.

Laparoscopy-assisted distal gastrectomy for early gastric cancer: is it beneficial for patients of heavier weight?

OBJECTIVE

In this retrospective review, we evaluated the advantages and disadvantages of LADG for patients of heavier weight with early gastric cancer.

SUMMARY BACKGROUND DATA

LADG has been used to treat early gastric cancer. We and others have reported less operative blood loss, less pain, early recovery of bowel activity, early restart of oral intake, and a shorter hospital stay with LADG compared with a conventional open method. There is, however, little information on the advantages of LADG for obese patients with early gastric cancer.

METHODS

Between January 1996 and March 2002, 76 patients with preoperatively diagnosed early gastric carcinoma underwent LADG in our department. We classified these patients into 2 groups on the basis of body mass index (BMI). Nineteen patients had a high-BMI (>/= 24.2 kg/m2), and 57 patients had a normal-BMI (<24.2 kg/m2). We collected data by retrospectively reviewing the medical charts.

RESULTS

Extension of the minilaparotomic incision or conversion to laparotomy was needed in 6 (32%) of the 19 patients in the high-BMI group, whereas only 3 (5%) of 57 patients in the normal-BMI group required either. In the high-BMI group, Roux-en-Y anastomosis rather than Billroth I anastomosis was adopted more often than in the normal-BMI group, due to the difficulty of the reconstruction (58% versus 4%, P = 0.001). Significantly longer operative time (370 +/- 61 minutes versus 317 +/- 58 minutes, P = 0.015) and prolonged recovery of bowel activity (3.5 +/- 1.0 days versus 2.6 +/- 1.0 days, P = 0.007) were observed in the patients in the high-BMI group.

CONCLUSIONS

In the current study, LADG in patients of heavier weight was accompanied by more technical difficulties, and the disadvantages of longer operative time and delayed recovery of bowel activity was observed in patients of heavier weight. Heavier weight appears to be an ominous factor in the successful completion of LADG and should be considered in the decision to use LADG. There are still benefits of a decreased incidence of serious wound and hernia complications in successful cases.

Prognostic significance of the number of metastatic lymph nodes in early gastric cancer

BACKGROUND

The prognostic value of the number of metastatic lymph nodes in early gastric cancer has not been evaluated much, although the significance of metastatic lymph nodes is defined by the location of positive nodes, according to the JRSGC for gastric cancer.

METHODS

The postoperative courses of 305 early gastric cancer patients who had undergone D2-extended lymphadenectomy were followed up for a median of 108 months to evaluate the significance of the number of metastatic lymph nodes on recurrence of the disease.

RESULTS

Recurrence of gastric cancer was more frequently observed in submucosal cancer than in mucosal cancer. All patients but one who revealed recurrence had nodal metastasis at the time of surgery. In cases with 1-3 metastatic lymph nodes, no patient had revealed any sign of recurrence; however, in cases with 4 or more metastatic lymph nodes, 6 of 7 patients died of recurrent disease. There were 3 cases of bone metastases, 2 of peritoneal dissemination, and 1 each of both recurrent diseases.

CONCLUSIONS

These data suggest that in n-positive cases, in which there are 4 or more metastatic lymph nodes, there is a high probability of recurrence of early gastric cancer, and especially of hematogenic metastasis.

Endoscopic interventions for preneoplastic and neoplastic lesions: mucosectomy, argon plasma coagulation, and photodynamic therapy

The classical treatment of neoplastic lesions is surgical resection. Improved detection of early lesions has offered new therapeutic strategies. Thus, for the last 20 years it has been increasingly attempted to undertake endoscopic resection of such tumors. While there is no doubt that morbidity and mortality are lower than after surgery, it was assumed that the long-term prognosis is not as good as with surgery. Surprisingly, however, the 5-year survival rates are excellent. Therefore, in local mucosal lesions of colon, stomach, and esophagus, endoscopic removal has become standard treatment. In Barrett's esophagus, the treatment modality it is still discussed controversially, despite encouraging results. Since we are yet not able to completely eliminate the premalignant specialized intestinal epithelium of the esophagus, it is still uncertain whether eradication of the malignant or dysplastic lesion is sufficient.

Modern treatment of early gastric cancer: review of the Japanese experience

BACKGROUND

Recently, detections of early gastric cancer (EGC) have been increasing, and the treatment strategies for gastric cancer have been changing. To demonstrate recent clinical experience of EGC in Japan and to assess modern strategies for the treatment of EGC, we investigated the English-language literature of the past 10 years through computer searches.

METHODS

This article intends to provide gastric surgeons with recent Japanese experience of the treatment for EGC. In a search for modern treatments of EGC, we selected 100 papers published in well-known medical journals, and focused on the following items of EGC: (1) prognostic factors, (2) endoscopic treatment, (3) surgical procedures, and (4) Japanese guidelines.

RESULTS

The most important factor influencing the survival of patients with EGC is the status of lymph node metastasis. The incidence of lymph node metastasis is 1-3% for mucosal cancers and 11-20% for submucosal cancers. Endoscopic mucosal resection (EMR) is a technique for the treatment of EGC, and the recent indication includes the tumors confined to the mucosa up to 3 cm in size or those invading the superficial submucosa. Surgical procedures include conventional Billroth I gastrectomy, limited resections, and laparoscopic surgery. Laparoscopic wedge resection using the lesion-lifting method and laparoscopy-assisted distal gastrectomy provide less pain, faster recovery and shorter hospital stay. Guidelines for the treatment of gastric cancer proposed by the Japanese Gastric Cancer Association show that patients with mucosal cancer can be managed by EMR or distal gastrectomy, whereas patients with submucosal cancer are candidates for distal gastrectomy with lymph node dissection.

CONCLUSION

Although the prognosis of patients with EGC depends on the presence or absence of lymph node metastasis, most are successfully treated by modern endoscopic or surgical techniques. Laparoscopic surgery and limited resections will contribute to the better quality of life of patients with EGC.

Hand-assisted laparoscopic total gastrectomy

Although the standard method to manage gastric cancer is still radical gastrectomy, minimally invasive surgery is of great interest in early gastric cancer because of its potential impact on improving the quality of life, if the disease is curable. With its degree of technical difficulty, laparoscopic total gastrectomy has not yet met with widespread acceptance. However, using a hand-access device, a total gastrectomy and Roux-en-Y esophagojejunostomy with a D1 plus alpha lymph node dissection and omentectomy with an Ultrashear was performed in its entirety. The operation took 6 hours, and the blood loss was 500 mL. The patient recovered uneventfully and was discharged on the 16th postoperative day. In terms of recovery and quality of life, laparoscopic total gastrectomy is a technically feasible and reasonable option for the management of early gastric cancer in the proximal stomach, especially when an endoscopic mucosal resection is not indicated.

Editorial comment: feasibility of central gastrectomy for gastric cancer

BACKGROUND

Central gastrectomy (CG) for gastric cancer was developed to preserve pyloric function and maintain a large gastric volume. Whether this procedure is feasible for limited cases of gastric cancer is unclear.

METHODS

On the basis of Union Internationale Contre le Cancer TNM classification, pathologic characteristics, perioperative parameters, and long-term results, we analyzed 100 patients who underwent CG.

RESULTS

Pathologic findings included T1 (tumor depth, mucosal or submucosal) in 82 patients and T2 (muscularis propria or subserosal) in 18 patients. Mean number of dissected lymph nodes was 17.3, and pathologic N1 (node metastasis, 6 or less) was found in 14 patients. There were no operative deaths, but 5 patients had postoperative complications: anastomotic leakage in 1, severe gastric stasis in 2, ischemic gastric ulcer in 1, and intra-abdominal bleeding in 1. No patient had a cancer recurrence in a mean follow-up of 49 months. New early gastric cancer was detected in 3 patients during follow-up endoscopic examination. The 5-year cumulative survival was 0.97. One year after CG, 63 patients had early satiety after food intake. Mean ratio of 1-year postoperative/preoperative body weight was 95%.

CONCLUSIONS

Central gastrectomy with sufficient node dissection resulted in good long-term survival and minimal postoperative weight loss. CG is a safe and useful procedure for selected patients with gastric cancer, although close follow-up for recurrence and a more precise analysis on physiologic states is needed.

Indications of a minimized scope of lymphadenectomy for submucosal gastric cancer

BACKGROUND

A recent trend for less invasive surgery has increased consideration for a minimized scope of lymphadenectomy for submucosal cancer; however, feasibility criteria have not been precisely established.

METHODS

Patterns and sites of nodal involvement were retrospectively investigated in 294 patients with solitary submucosal gastric cancer in association with other clinicopathologic characteristics, including pre- and intraoperative evaluations of cancer depth (cT) and nodal involvement (cN).

RESULTS

Among the early (cT1) and node-negative (cN0) cancer, intestinal (< or =1.5 cm) and diffuse types (< or =1.0 cm) of submucosal cancer showed low incidences of nodal involvement (3%) confined to the first tier. When the cancer exceeded these cutoff diameters, positive nodes of the second tier were confined to three priority stations (left gastric, common hepatic, and celiac arteries) at an incidence of 2.3%. Perigastric and preferential dissection of these three node stations (modified D2 dissection) showed survival benefits identical to those of a conventional D2 dissection.

CONCLUSIONS

When submucosal cancer is evaluated as cT1cN0, a virtually sufficient minimized scope of lymphadenectomy is a D1 dissection for that within the cutoff diameter and a modified D2 dissection for that exceeding the cutoff diameter. These two types of dissection can even cover the infrequently observed node-positive stations and can realize no residual disease at surgery.