Feasibility of pylorus-preserving gastrectomy with a wider scope of lymphadenectomy

Pathological and oncological outcomes of pylorus-preserving versus conventional distal gastrectomy in early gastric cancer: a systematic review and meta-analysis

Background

Pylorus-preserving gastrectomy (PPG) is a function-preserving surgery for the treatment of early gastric cancer (EGC) in the middle third of the stomach. According to the literature reports, PPG decreases the incidence of dumping syndrome, bile reflux, gallstone formation, and nutritional deficit compared with conventional distal gastrectomy (CDG). However, the debates about PPG have been dominated by the incomplete lymphadenectomy and oncological safety. We carried out a systematic review and meta-analysis to evaluate the pathological and oncological outcomes of PPG.

Methods

The protocol was registered in PROSPERO under number CRD42022304677. Databases including PubMed, Embase, Web of Science, and the Cochrane Register of Controlled Trials were searched before February 21, 2022. The outcomes included the pooled odds ratios (ORs) for dichotomous variables and weighted mean differences (WMDs) for continuous variables. For all outcomes, 95% confidence intervals (CIs) were calculated. Meta-analysis was performed using STATA software (Stata 14, Stata Corporation, Texas) and Review Manager 5.4.

Results

A total of 4500 patients from 16 studies were included. Compared with the CDG group, the PPG group had fewer lymph nodes harvested (WMD= −3.09; 95% CI −4.75 to −1.43; P < 0.001). Differences in the number of resected lymph nodes were observed at stations No. 5, No. 6, No. 9, and No. 11p. There were no differences in lymph node metastasis at each station. Shorter proximal resection margins (WMD = −0.554; 95% CI −0.999 to −0.108; P = 0.015) and distal resection margins (WMD = −1.569; 95% CI −3.132 to −0.007; P = 0.049) were observed in the PPG group. There were no significant differences in pathological T1a stage (OR = 0.99; 95% CI 0.80 to 1.23; P = 0.88), T1b stage (OR = 1.01; 95% CI 0.81 to 1.26; P = 0.88), N0 stage (OR = 0.97; 95% CI 0.63 to 1.48; P = 0.88), tumor size (WMD = −0.10; 95% CI −0.25 to 0.05; P = 0.187), differentiated carcinoma (OR = 1.04; 95% CI 0.74 to 1.47; P = 0.812) or signet ring cell carcinoma (OR = 1.22; 95% CI 0.90 to 1.64; P = 0.198). No significant differences were observed between the groups in terms of overall survival (HR = 0.63; 95% CI 0.24 to 1.67; P = 0.852) or recurrence-free survival (HR = 0.29; 95% CI 0.03 to 2.67; P = 0.900).

Conclusions

The meta-analysis of existing evidence demonstrated that the survival outcomes of PPG may be comparable to those of CDG. However, fewer lymph nodes at stations in No. 5, No. 6, No. 9, and No. 11p were harvested with PPG. We also found shorter proximal resection margins and distal resection margins for PPG, meaning more remnant stomachs would be preserved in PPG.

A comparison between pylorus-preserving and distal gastrectomy in surgical safety and functional benefit with gastric cancer: a systematic review and meta-analysis

BACKGROUND

Due to better functional outcomes, pylorus-preserving gastrectomy (PPG) has been widely applied for early gastric cancer (EGC) patients as an alternative to distal gastrectomy (DG). However, controversies still persist regarding the surgical efficacy and oncological safety of PPG.

METHODS

Original studies comparing PPG and DG for EGC were searched in PubMed, Embase, and the Cochrane Register of Controlled Trials up to December 2019. The weight mean difference, standardized mean difference, or odds risk was used to calculate the short-term and long-term outcomes between the two groups.

RESULTS

Twenty-one comparative studies comprising 4871 patients (1955 in the PPG group and 2916 in the DG group) were enrolled in this systematic review and meta-analysis. PPG showed longer hospital day, decreased harvested lymph nodes, and more delayed gastric emptying. However, PPG had the benefits of lower incidence of anastomosis leakage, early dumping syndrome, gastritis and bile reflux, and better recovery of total protein, albumin, hemoglobin, and weight. No difference was found in operative time, blood loss, and overall complications. Moreover, the long-term survival and recurrence rate were similar in two groups.

CONCLUSION

Owing to the non-inferiority of surgery and oncology outcomes and the superiority of function outcomes in PPG, we revealed that PPG can be clinically applicable instead of DG in EGC. However, more high-quality comparative studies and randomized clinical trials would be required for further confirmation.

Risk factors for lymph node metastasis in non-sentinel node basins in early gastric cancer: sentinel node concept

BACKGROUND

Sentinel node (SN) concept is being applied to early gastric cancer. However, when SNs are positive for metastasis, it is unclear how often LNs in other LN basins show metastasis. We aimed to investigate LN metastasis possibility in LN basins without SNs (non-SN basins). We determined risk factors for metastasis in non-SN basins and identified a prediction model for non-SN basin metastasis using classification and regression tree (CART) analysis.

METHODS

We enrolled 550 patients who were diagnosed with cT1N0M0 or cT2N0M0 gastric cancer with a single lesion and underwent SN mapping. We adopted a dual-tracer method using a radioactive colloid and blue dye to detect SNs.

RESULTS

Of all, 45 (8.2%) patients had SN metastasis; we divided them into two groups: LN metastasis positive and LN metastasis negative in non-SN basins. Univariate analysis showed that the groups differed significantly regarding lymphatic invasion (p = 0.007), number of identified SNs (p = 0.032), and macrometastasis in SN basins (p = 0.005). The CART decision tree for predicting LN metastasis in non-SN basins had area under the curve value of 0.86. Moreover, there were significantly differences in cancer-specific survival (CSS) between the two groups (p = 0.028).

CONCLUSIONS

Macrometastasis in SN basins, lymphatic invasion, and number of identified SNs ≥ 5 are risk factors for LN metastasis in non-SN basins among gastric cancer patients. We identified a prediction model with CART analysis; patients with macrometastasis in SN basins and lymphatic invasion were considered to be at the highest risk for LN metastasis.

Preservation of the celiac branch of the vagal nerve for pylorus-preserving gastrectomy: is it meaningful?

BACKGROUND

Preserving the hepatic and pyloric branches of the vagal nerve in laparoscopic pylorus-preserving gastrectomy (LPPG) is considered necessary to maintain the function of the pyloric cuff. However, the clinical benefits of preservation of the celiac branch of the vagal nerve (CBVN) remain unclear.

METHODS

Of 391 patients who underwent LPPG for early gastric cancer, 116 patients in whom the CBVN was preserved (CBP group) and 58 patients in whom it was not preserved (non-CBP group) were selected through the propensity score-matching method. To evaluate the surgical and oncological safety of preserving the CBVN, postoperative morbidity and mortality were analyzed between these matched groups. Postoperative nutritional status, body weight changes, endoscopic findings, and the incidence of gallstones were compared to evaluate any functional advantages.

RESULTS

The short-term surgical outcomes in the CBP group were similar to those in the non-CBP group. The number of dissected lymph nodes did not differ (34 vs. 33.5, P = 0.457), and the 5-year recurrence-free survival rates were also similar between both groups (99.1% vs. 97.1%, P = 0.844). There were no significant differences in postoperative nutritional status, body weight changes, or the incidence of gallstones. By endoscopy, 1 year after surgery residual food was frequently observed in both groups; however, there were no significant differences in the frequency of remnant gastritis and esophageal and bile reflux.

CONCLUSIONS

Preserving CBVN in LPPG for early gastric cancer is a feasible procedure. However, no clinical benefits of the preservation of the CBVN after LPPG are identified.

功能保留手术在早期胃癌治疗中的作用

随着人们健康意识的增加和胃镜等医疗诊断技术的不断进步, 早期胃癌的诊断率逐年上升. 早期胃癌的功能保留胃切除术是在根治原发病灶, 行标准淋巴结清扫前提下, 限制胃切除范围, 同时保留幽门及迷走神经功能, 以达到改善患者术后生活质量的目的, 其手术方式包括: 保留幽门的胃切除术, 近端胃切除术, 胃节段切除以及局部切除. 此外, 内镜下黏膜切除术和黏膜剥离也被认为属于功能保留胃切除术范畴. 对于大部分早期胃癌患者, 根治性手术具有良好的治疗效果, 其5年生存率在90%以上. 因此, 在达到手术根治目的的前提下, 保留部分胃的解剖和生理功能, 提高患者术后的生活质量, 对早期胃癌患者具有重要的意义.

Pylorus-Preserving Gastrectomy for Gastric Cancer

Pylorus-preserving gastrectomy (PPG) is a function-preserving surgery for the treatment of early gastric cancer (EGC), aiming to decrease the complication rate and improve postoperative quality of life. According to the Japanese gastric cancer treatment guidelines, PPG can be performed for cT1N0M0 gastric cancer located in the middle-third of the stomach, at least 4.0 cm away from the pylorus. Although the length of the antral cuff gradually increased, from 1.5 cm during the initial use of the procedure to 3.0 cm currently, its optimal length still remains unclear. Standard procedures for the preservation of pyloric function, infra-pyloric vessels, and hepatic branch of the vagus nerve, make PPG technically more difficult and raise concerns about incomplete lymph node dissection. The short- and long-term oncological and survival outcomes of PPG were comparable to those for distal gastrectomy, but with several advantages such as a lower incidence of dumping syndrome, bile reflux, and gallstone formation, and improved nutritional status. Gastric stasis, a typical complication of PPG, can be effectively treated by balloon dilatation and stent insertion. Robot-assisted pylorus-preserving gastrectomy is feasible for EGC in the middle-third of the stomach in terms of the short-term clinical outcome. However, any benefits over laparoscopy-assisted PPG (LAPPG) from the patient's perspective have not yet been proven. An ongoing Korean multicenter randomized controlled trial (KLASS-04), which compares LAPPG and laparoscopy-assisted distal gastrectomy for EGC in the middle-third of the stomach, may provide more clear evidence about the advantages and oncologic safety of PPG.

Totally laparoscopic pylorus-preserving gastrectomy for early gastric cancer in the middle stomach: technical report and surgical outcomes

INTRODUCTION

The feasibility, safety, and improved quality of postoperative life following laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) with a hand-sewn anastomosis via a mini-laparotomy for early gastric cancer (EGC) have been previously established. Here we describe the surgical procedure of totally laparoscopic pylorus-preserving gastrectomy (TLPPG) using an intracorporeal delta-shaped anastomosis technique, and the short-term surgical outcomes of 60 patients with EGC in the middle stomach are reported.

METHODS

After lymphadenectomy and mobilization of the stomach, intraoperative gastroscopy was performed in order to verify the location of the tumor, and then the distal and proximal transecting lines were established, 5 cm from the pyloric ring and just proximal to Demel's line, respectively. Following transection of the stomach, a delta-shaped intracorporeal gastrogastrostomy was made with linear staplers.

RESULTS

There were no intraoperative complications or conversions to open surgery. Mean operation time and blood loss were 259 min and 28 mL, respectively. Twelve patients (20.0%) experienced postoperative complications classified as grade II using the Clavien-Dindo classification, with the most frequent complication being gastric stasis (6 cases, 10.0 %). The incidence of severe complications classified as grade III or above was 1.7%; only one patient required reoperation and intensive care due to postoperative intraabdominal bleeding and subsequent multiple organ failure.

CONCLUSION

TLPPG with an intracorporeal delta-shaped anastomosis was found to be a safe procedure, although it tended to require a longer operating time than the well-established LAPPG with a hand-sewn gastrogastrostomy.

Meta-analysis of pylorus-preserving gastrectomy for middle-third early gastric cancer

BACKGROUND

Pylorus-preserving gastrectomy (PPG) has been performed to reduce postprandial symptoms for some early gastric cancer (EGC) cases. The aim of this study was to evaluate the possible advantages after PPG for middle-third EGC in comparison with distal gastrectomy.

MATERIALS AND METHODS

We searched Medline, Embase, and Science Citation Index Expanded for relevant studies. Statistical analyses were conducted to calculate the summary weighted mean differences (WMDs) and odds ratios (ORs) with corresponding 95% confidence intervals (95% CIs) using random-effects models.

RESULTS

We identified 15 nonrandomized controlled trials (16 studies) with 1774 patients, which consisted of 11 studies for conventional PPG (CPPG) versus conventional distal gastrectomy (CDG) and 5 studies for laparoscopy-assisted PPG (LAPPG) versus laparoscopy-assisted distal gastrectomy (LADG). Meta-analysis of CPPG versus CDG revealed that CPPG had the advantage of prevention of early dumping syndrome (OR=0.18; 95% CI 0.12, 0.27), gastritis (OR=0.19; 95% CI 0.07, 0.53), duodenal juice reflux (OR=0.20; 95% CI 0.06, 0.66), and regaining of weight (WMD=3.53; 95% CI 2.34, 4.72). However, the incidence of gastric stasis was higher in the CPPG group than in the CDG group (OR=1.70; 95% CI 1.13, 2.57). Meta-analysis of LAPPG versus LADG revealed that LAPPG shortened the operation time (WMD=-21.12; 95% CI -31.33, -10.90) and did not increase the occurrence of postoperative complication (OR=0.72; 95% CI 0.41, 1.27).

CONCLUSIONS

With the benefits of prevention of early dumping syndrome, duodenal juice reflux, gastritis, and regaining of weight, PPG can be an excellent option for middle-third EGC.

Quality of life after laparoscopy-assisted pylorus-preserving gastrectomy: an evaluation using a questionnaire mailed to the patients

PURPOSE

This study investigated the postoperative quality of life (QOL) after laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) in comparison to laparoscopy-assisted distal gastrectomy (LADG).

METHODS

Twenty-one patients with early-stage gastric cancer underwent minimally invasive LADG (n = 12) or LAPPG (n = 9). Demographic and cancer-related data were obtained retrospectively from medical records. QOL was assessed using a 13-item questionnaire and the Japanese edition of the Gastrointestinal Symptom Rating Scale, which were mailed to patients twice postoperatively. Body weight and hemoglobin levels were measured at the same time.

RESULTS

Early upper abdominal pain was rated as significantly worse with LAPPG than with LADG at the first checkup (1.4 vs. 1.0, P = 0.02) but not at the second checkup (1.3 vs. 1.0, P = 0.07). There was a trend toward less body weight loss in the LAPPG patients in comparison to the LADG patients. The serum hemoglobin levels of LAPPG patients at the second checkup showed significantly higher than LADG patients (13.3 vs. 11.6 g/dL, P < 0.05).

CONCLUSIONS

LAPPG and LADG produce similar QOL in patients. Trends toward less body weight loss and improved anemia in LAPPG patients may therefore become more pronounced in future studies that have adequate number of the patients and longer follow-up periods.

Nutritional assessment of patients after pylorus-preserving gastrectomy for early gastric cancer

The aim of this study was to evaluate the nutritional advantages of pylorus-preserving gastrectomy (PPG) in comparison with distal gastrectomy with Billroth I anastomosis (DG) in early gastric cancer (EGC). Between 2005 and 2007, 24 patients underwent PPG and 30 underwent DG. Subjective global assessment, objective data assessment, and endoscopic findings of the remnant stomach were compared between the two groups. Two years after surgery, the patients' body weights recovered to 97% in PPG, but they continued to decrease in DG. Postoperative blood lymphocyte counts remained low in DG, but recovered to preoperative levels 6 months after surgery in PPG. Food residue in the gastric remnant was frequently observed in PPG (71.4%) than in DG (15.8%, P = 0.001). In nutritional aspect, PPG may be a more ideal operation than DG. However, food residue in the gastric remnant should be considered in PPG.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (doi:10.1007/s12262-010-0167-4) contains supplementary material, which is available to authorized users.

Vagus nerve preservation selectively restores visceral fat volume in patients with early gastric cancer who underwent gastrectomy

BACKGROUND

Body weight loss is a well-known complication after gastrectomy, and is mainly due to reduced fat volume. The effect of vagotomy on the postoperative fat volume was investigated in patients with early stage gastric cancer who underwent gastrectomy.

METHODS

Subcutaneous fat area (SFA) and visceral fat area (VFA) were separately measured in a computed tomographic (CT) image at the level of the umbilicus using Fat Scan software. The changes in these two fat areas were determined by comparing CT images taken before and more than 6 mo after gastrectomy, and the ratio of postoperative to preoperative fat area was calculated in 77 patients.

RESULTS

VFA was reduced significantly greater after total gastrectomy (TG) than distal gastrectomy (DG) (P = 0.0003). In 63 patients who underwent DG, the reduction in VFA, but not in SFA, was significantly less in vagus nerve-preserved than in vagus nerve-nonpreserved cases (59.0% ± 24.2% versus 74.9% ± 28.2%, P = 0.027). If compared in each case, VFA showed a significantly greater decrease than did SFA in vagus-nonpreserving, but not in vagus-preserving, gastrectomy (68.2% ± 37.0% versus 52.7% ± 25.2%, P < 0.0001; 76.3% ± 30.0% versus 74.9% ± 28.2%, P = 0.79).

CONCLUSIONS

The vagus nerve has a function to locally regulate the amount of intra-abdominal fat tissue, and selective vagotomy in gastrectomy results in a preferential reduction of visceral fat in gastrectomy. Surgical denervation of vagus may be reconsidered as a reasonable treatment for excessive obesity.

Evaluation of the adequacy of lymph node dissection in pylorus-preserving gastrectomy for early gastric cancer using the maruyama index

BACKGROUND

The Maruyama computer program predicts the percentage likelihood of disease in lymph node stations left undissected by a surgeon, according to the age and sex of the patient and the gross type, size, location, depth of invasion, and histology of the tumor. The Maruyama index (MI) is defined as the sum of the predictions of the percentage likelihood of disease in undissected regional lymph node station (station 1-12). It has been shown that an MI < 5 is a strong predictor of survival and that the MI is an independent predictor of overall survival and relapse risk. We used the MI to evaluate the adequacy of lymph nodes dissection in pylorus-preserving gastrectomy (PPG) for early gastric cancer (EGC) performed at Seoul National University Hospital.

METHODS

From March 2003 to September 2007, PPG was performed for patients with EGC of the middle third of the stomach when the distal resection margin was greater than 2 cm and preservation of 3 cm antral segment was possible. MIs and pathologic data such as TNM stage and the presence of metastatic lymph node for each station were reviewed.

RESULTS

PPG were performed on 24 patients. The mean age of the patients was 55 years. The median tumor size was 2.1 cm. The median and mean MI were 0 and 0.8, respectively. There were 23 cases of T1N0M0 tumor and one case of T2N0M0 tumor postoperatively. There were no recurrences (mean follow-up period: 27.2 months).

CONCLUSIONS

The MI indicates that lymph node dissection during PPG performed in these 24 patients was adequate.

The safety of the dissection of lymph node stations 5 and 6 in pylorus-preserving gastrectomy

BACKGROUND

This study was intended to examine the safety of possibly incomplete dissection of lymph node stations (LNS) 5 and 6 in pylorus-preserving gastrectomy (PPG) for gastric cancer.

MATERIALS AND METHODS

We reviewed the medical information from 1802 gastric cancer patients who underwent curative gastrectomy and whose lymph nodes were topographically classified according to LNS between March 2003 and December 2008. We divided the patients who underwent subtotal gastrectomy into 2 groups according to the distance between the distal resection margin (DRM) and primary tumor: those with a distance of < 6 cm (the < 6 DRM group) and those with a distance of >or= 6 cm (the >or= 6 DRM group). We analyzed the lymph node metastasis rate to LNS 5 and 6 according to T stage and the location. The number of retrieved lymph nodes according to LNS was compared between subtotal gastrectomy (STG) and PPG.

RESULTS

The metastasis rate to LNS 5 was very rare in >or= 6 DRM group: T1a, 0% (0 of 105); T1b, 0.9% (1 of 113); and T2a, 0% (0 of 56), although the number of retrieved LNS 5 was significantly lower in PPG than in STG. The metastasis rate to LNS 6 in the >or= 6 DRM group was significantly lower than in the < 6 DRM group, but higher than that of LNS 5: T1a, 0% (0 of 107); T1b, 1.8% (2 of 114); and T2a, 3.6% (2 of 56). The number of retrieved LNS 6 was not significantly different between STG and PPG.

CONCLUSIONS

PPG seems to be safe for early gastric cancer located >or= 5 cm from the pylorus in terms of LNS 5 and 6.

Evaluation of a pylorus-preserving gastrectomy for patients preoperatively diagnosed with early gastric cancer located in the middle third of the stomach

PURPOSE

Patients diagnosed with early gastric cancer located in the middle third of the stomach have two major surgical options, namely a conventional distal gastrectomy with Billroth I anastomosis (DG) or a pylorus-preserving gastrectomy (PPG). Pyloruspreserving gastrectomy is thought to have greater functional benefits than DG, but the evaluation of its prognosis and outcome has so far been insufficient.

METHODS

Between 1997 and 2007, 133 patients were diagnosed with early gastric cancer located in the middle third of the stomach. Distal gastrectomy was performed in 87 and PPG was performed in 46 of these patients. The clinicopathological characteristics were compared between the groups.

RESULTS

There were fewer dissected lymph nodes in PPG (mean: 21.9) than in DG (mean: 30.4, P = 0.001). Complications were detected in 16.1% of DG patients and in 6.5% of PPG patients. The occurrence of stasis after PPG (6.5%) was similar to that observed after DG (6.9%). One patient in the DG group died from cancer recurrence, but cancer recurrence was not detected in the PPG group. Although the difference was not significant, the overall 5-year survival rate in the 46 PPG patients (95%) was better than that in the 87 DG patients (86%, P = 0.087).

CONCLUSIONS

Pylorus-preserving gastrectomy patients had fewer postoperative complications than DG patients. The long-term follow-up of these patients will clarify the nutritional and prognostic benefits of PPG.

Clinical outcome of pylorus-preserving gastrectomy in gastric cancer in comparison with conventional distal gastrectomy with Billroth I anastomosis

BACKGROUND

Pylorus-preserving gastrectomy (PPG) was originally a treatment option in gastric ulcer surgery and is now being performed as a limited surgery in some early gastric cancer cases. This study was designed to evaluate the postoperative functional characteristics of PPG versus conventional distal gastrectomy with Billroth I anastomosis (BI).

METHODS

Patients who underwent PPG (study group) between November 1999 and April 2003 were enrolled and BI patients (control group) were matched for number, gender, age, weight, height, stage, and follow-up period. We evaluated postprandial symptoms and nutritional status. Gastric emptying studies with a 99mTc gamma camera, follow-up endoscopies with random biopsies of remnant gastric mucosa to evaluate bile reflux gastritis, and ultrasonography to detect gallbladder stones were performed. Recurrence and survival also were investigated.

RESULTS

Twenty-two PPG patients (study group) and 17 BI patients (control group) were enrolled. Overall modified Visick scores of postprandial symptoms were lower in PPG patients than in BI patients (0.9 +/- 0.7 vs. 2.3 +/- 1.4; p = 0.018). Gastric emptying was delayed in PPG patients versus BI patients for solids (p < 0.05). Moderate gastritis, bile reflux, and gallbladder stone were observed only in BI patients. Remnant stomach pathologic findings corresponding to bile reflux gastritis in the two groups were similar, except for Helicobacter pylori colonization. No recurrence occurred in either group (mean follow-up period = 41 +/- 9.5 months).

CONCLUSIONS

PPG patients had fewer subjective postprandial symptoms than BI patients. The present study also suggests that PPG has advantages over BI in terms of the avoidance of bile reflux and gallbladder stones.

Outcome of pylorus-preserving gastrectomy for early gastric cancer

Background

Pylorus-preserving gastrectomy has been introduced as a function-preserving operation for early gastric cancer in Japan. The aim of this study was to investigate the safety and radicality of the procedure.

Methods

Between 1995 and 2004, 611 patients with apparent early gastric cancer in the middle third of the stomach had pylorus-preserving gastrectomy. The short-term surgical and long-term oncological outcomes of these operations were assessed.

Results

The accuracy of preoperative diagnosis of early gastric cancer was 94·3 per cent. Nodal involvement was seen in 62 patients (10·1 per cent). There were no postoperative deaths. Complications developed in 102 patients (16·7 per cent). Major complications, such as leakage and abscess, were observed in 19 (3·1 per cent). The most common complication was gastric stasis, occurring in 49 (8·0 per cent). The overall 5-year survival rate in patients with early gastric cancer was 96·3 per cent.

Conclusion

Pylorus-preserving gastrectomy is a safe operation with an excellent prognosis in patients with early gastric cancer. It is recommended as the standard procedure for early gastric cancer in the middle third of the stomach.

Gastroesophageal carcinoma: individualized surgical therapy

During the twentieth century, surgical management of gastroesophageal carcinoma was developed by an establishment of standard procedures with lymph node dissection according to the metastatic distribution. The "fear" of invisible micrometastasis caused surgeons to perform more aggressive resection with lymphadenectomy to control the disease locally. Although several promising results of extensive lymph node dissection have been reported, the prognostic benefits of extensive surgery have not been proven by prospective randomized trials. A novel technology to detect micrometastasis without extensive surgical resection is required to gastroesophageal carcinoma. The lymphatic mapping technique is one of the attractive candidates for a novel tool to approach this issue.

Assessment of the preserved function of the remnant stomach in pylorus-preserving gastrectomy by gastric emptying scintigraphy

BACKGROUND

This study evaluated the preserved function of the remnant stomach by gastric emptying scintigraphy in patients who underwent pylorus-preserving gastrectomy (PPG), and it investigated whether this examination method is a useful tool for evaluation.

MATERIALS AND METHODS

The residual stomach function was evaluated by gastric emptying scintigraphy in 45 patients with early gastric cancer who had undergone PPG. Function was classified as rapid, intermediate, and delayed emptying types according to gastric emptying curves. Then, the relationships were examined between the gastric emptying types and postprandial symptoms, food intake status, body weight changes, and endoscopic findings.

RESULTS

Seventy-three percent of the PPG patients were classified as belonging to the intermediate emptying type, and the remainder to the delayed emptying type. The frequencies of complaints such as epigastric fullness, nausea, and vomiting were high in the delayed emptying-type patients. The intermediate emptying-type patients consumed larger amounts of food and gained more weight than the delayed emptying-type patients. It was difficult to estimate gastric emptying function from endoscopic findings.

CONCLUSIONS

Gastric function was evaluated by gastric emptying scintigraphy in PPG patients. This method might be useful not only for evaluating the motor function of the remnant stomach, but also for predicting postoperative status.

Laparoscopy-assisted pylorus-preserving gastrectomy with quality controlled lymph node dissection in gastric cancer operation

BACKGROUND

Pylorus-preserving gastrectomy (PPG) with extensive lymph node dissection is useful for treatment of early gastric cancer with preservation of function. This technique could be improved by using laparoscopy-assisted gastrectomy.

STUDY DESIGN

Between September 2000 and September 2004, 109 patients with T1 gastric cancer underwent surgical treatment; 72 underwent laparoscopy-assisted PPG (LAPPG) and 37 underwent conventional PPG (CPPG). Total numbers of dissected lymph nodes, retrieval at each lymph node station, intraoperative blood loss, and operation times were used as measures of the quality of lymph node dissection to compare the procedures. Continuous data are summarized as mean +/- SE.

RESULTS

Operation times with the LAPPG procedure (279 +/- 6 minutes) were significantly, but only 20 minutes, longer than with CPPG (259 +/- 8 minutes) (p = 0.047), although estimated blood loss for LAPPG patients (153 +/- 13 mL) was not significantly different for those undergoing CPPG (184 +/- 13 mL, p = 0.13). Mean total number of dissected lymph nodes was 32.3 +/- 1.6 in the LAPPG group and 28.5 +/- 2.2 in the CPPG group (p = 0.16). There was no significant difference in the number of lymph nodes retrieved for any of the nodal stations between the LAPPG and CPPG procedures.

CONCLUSIONS

Clinical outcomes of surgical treatment were comparable for gastric cancer patients who underwent LAPPG and those treated with CPPG in terms of station-dependent lymph node dissection and estimated blood loss.

Diagnosis of gastric cancer with MDCT using the water-filling method and multiplanar reconstruction: CT-histologic correlation

OBJECTIVE

The purpose of this study was to assess the utility of MDCT with a thin-sliced multiplanar reconstruction (MPR) technique and water-filling method for the diagnosis of gastric cancers.

MATERIALS AND METHODS

Sixty-five patients with gastric cancers were preoperatively examined with MDCT using the water-filling method. The abdomen was dynamically scanned at 30 and 80 sec after the start of contrast medium administration. MPR images were reconstructed with a slice width of 1.25 mm and a slice interval of 1 mm. The detection rate and accuracy of T staging for gastric cancer were evaluated on MPR images and compared with 5-mm-slice axial images. In addition, MDCT images were correlated with pathologic findings.

RESULTS

The detection rate of all gastric cancers using the MPR technique was 65%. The detection rate of advanced gastric cancers was 96.2% (25 of 26), whereas that of early gastric cancers was 41.2% (14 of 34). There was a statistically significant difference (p < 0.05) in the detection rate of early gastric cancers between MPR and 5-mm-slice axial images. The MDCT appearances of gastric cancers were well correlated with pathologic findings such as mucinous component or differences in infiltration of cancer cells. The overall accuracy of CT staging was 85%. MPR images were superior to axial images for the evaluation of the z-axis extent of tumor.

CONCLUSION

MDCT with the water-filling method has advantages in acceptable evaluation of depth invasion of gastric carcinomas and in visualization of histologic changes in the tumors. MPR images may be a useful guide for the evaluation of the z-axis extent of tumor.

Pylorus-preserving gastrectomy in gastric cancer surgery--open and laparoscopic approaches

BACKGROUND AND AIMS

Pylorus-preserving gastrectomy (PPG) has been accepted as a function-preserving procedure for early gastric cancer for the prevention of postgastrectomy syndrome. In general, PPG procedures have not included suprapyloric lymph node dissection to preserve the pyloric branch of the vagal nerve and the right gastric artery. The aim of this article is to describe procedures for PPG. The technique of laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) is also introduced because PPG is an ideal application for laparoscopic surgery.

PATIENTS/METHODS

Between September 2000 and September 2004, we performed 37 cases of conventional PPG and further 73 cases of LAPPG. In these patients, PPG including complete lymph node dissection around the remnant pyloric cuff was performed. For this purpose, it is recommended that the blood flow to the pyloric cuff be maintained by preserving the infrapyloric artery.

RESULTS

All the patients showed good postoperative recovery, and no intraoperative or postoperative major complications were observed. No sign of recurrence was found in these 110 patients, and none of them demonstrated dumping syndrome.

CONCLUSION

The procedures of both PPG and LAPPG are technically feasible and have an important role in the surgical management of early gastric cancer in terms of better quality of postoperative life, even with lymphadenectomy including combined suprapyloric lymph node dissection and right gastric artery division.

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.

Concepts, rationale, and current outcomes of less invasive surgical strategies for early gastric cancer: data from a quarter-century of experience in a single institution

Previously proposed criteria of less invasive surgery for early gastric cancer (EGC) were based mainly on the pathological analyses of the resected specimens; however, preoperative and intraoperative information are also obviously essential for decision making on stage-dependent patient management. Furthermore, most indications and treatment options have not been systematically integrated or evaluated by treatment outcomes. We investigate in this report the rationality of less invasive surgery employed for EGC. Distribution analyses of positive nodes were investigated among 684 patients with primary solitary EGC (379 mucosal and 305 submucosal) who underwent curative resection between 1976 and 2000. Clinicopathological factors highlighted and analyzed included clinical (preoperative and intraoperative) and pathological (postoperative) cancer depth and nodal involvement, gross form, histological type, and maximum cancer diameter, as well as postoperative morbidity and mortality. The scope of lymphadenectomy can be reduced to a modified D1 for clinically mucosal, node-negative, nonpalpable gastric cancer, or for clinically submucosal, node-negative gastric cancer < or = 1.5 cm for intestinal type, or < or = 1.0 cm for diffuse type. Otherwise, a modified D2 lymphadenectomy is sufficient. Local resection can be recommended for clinically mucosal, node-negative gastric cancer without apparent ulceration < or = 4 cm if adjacent lymph nodes are proved cancer negative by a frozen section examination. If the gastric cancer has spread beyond the above criteria, a pylorus-preserving gastrectomy (PPG) can be recommended for tumors located in the middle or lower third of the stomach, provided the distal margin of the cancer is at least 4.5 cm from the pyloric ring. The PPG can be accompanied by a modified D1 or a modified D2 lymphadenectomy according to the respective dissection criteria. Results of these less invasive strategies showed reduced morbidity and mortality, as well as no recurrence or cancer-related deaths. These results suggest that each of our criteria for less invasive surgery for EGC is realistic, well stratified, and satisfactory.

Outcomes after pylorus-preserving gastrectomy for early gastric cancer: a prospective multicenter trial

The aim of the present study was to compare in a prospective, multicenter trial the results early and late after pylorus-preserving gastrectomy (PPG) versus conventional distal gastrectomy (CDG) with Billroth I anastomosis for early gastric cancer. Eighty-one patients with early gastric cancer were randomized and then underwent either PPG or CDG. Duration of operation, intraoperative blood loss, days until removal of the nasogastric tube, days until start of oral intake, and decrease in body weight were studied as parameters for outcomes early after the surgery. Late results were studied in patients followed for longer than 3 years. Change in body weight, status of oral intake, symptoms suggesting early dumping syndrome, and overall satisfaction were addressed in the questionnaire. The presence of gallstones was examined with ultrasonography. There were no differences in early results between PPG and CDG. The incidence of early dumping syndrome was lower in PPG (8%) than in CDG (33%). Other late results including the incidence of gallstones were not different between the 2 groups. These results indicate that PPG is as safe as CDG and has an advantage in terms of early dumping syndrome.

Gastric motility after laparoscopically assisted distal gastrectomy, with or without preservation of the pylorus, for early gastric cancer, as assessed by digital dynamic x-ray imaging

This study aimed to evaluate the usefulness of digital x-ray imaging for measuring gastric motility in patients subjected to laparoscopically assisted distal gastrectomy without preservation of the pylorus (LADG) or laparoscopically assisted pylorus-preserving gastrectomy (LAPPG) for early gastric cancer. Between April 1998 and February 2002, 52 patients with preoperative stage IA gastric cancer underwent laparoscopically assisted distal gastrectomy, with 26 receiving LADG for tumors in the lower third of the stomach and 26 receiving LAPPG for tumors in the middle third of the stomach. The gastric emptying ratio at 15 min after the ingestion of the test meal was 61.8% +/- 28.0% for LADG and 42.9% +/- 18.0% for LAPPG ( p < 0.01). The motility index was 2.65% +/- 2.54% for LADG and 8.13% +/- 2.46% for LAPPG ( p < 0.001). In conclusion, LAPPG results in better motility than LADG for patients with early gastric cancer arising in the middle third of the stomach.

Application of minimally invasive treatment for early gastric cancer

BACKGROUND AND OBJECTIVES

Although various types of minimally invasive treatment have emerged as the best front-line therapies for early gastric cancer (EGC), there have been no established indications that these attempts are applicable. The purpose of this study was to propose indications for the application of minimally invasive therapy for EGC.

METHODS

A total of 566 patients with EGC who had undergone gastrectomy with D2 or more extended lymphadenectomy, from July 1993 to December 1997 were retrospectively analyzed. The risk factors that determine lymph node metastasis were investigated by univariate and multivariate analysis.

RESULTS

The rate of lymph node metastasis was 11.8% for all EGC, 3.4% for mucosal cancer, and 21.0% for submucosal cancer. Lymph node metastasis was associated with submucosal invasion, larger tumor size, undifferentiated histology, and the presence of lymphatic or blood vessel invasion (LBVI) by univariate and multivariate analyses. When LBVI was absent, there was no lymph node metastasis if the tumor was smaller than 2.5 cm with differentiated histology, and smaller than 1.5 cm with undifferentiated histology, regardless of depth of invasion. Extra-perigastric lymph node metastases were noted in patients with submucosal tumors that have LBVI while none of mucosal cancer showed extra-perigastric lymph node metastases.

CONCLUSIONS

Minimally invasive treatment can be possibly applied for patients with EGC using these four independent risk factors for lymph node metastasis in EGC. For mucosal cancers, EMR is indicated for EGCs without lymph node involvement based on tumor size and histology. When we found LBVI by pathologic examination after EMR, gastrectomy with D1 lymph node dissection is mandatory. For submucosal cancers, patients with small tumors could be treated with laparoscopic wedge resection without lymph node dissection. However, patients with larger sized tumors or tumors with LBVI should be treated with extended (D2) lymph node dissection.

The role of surgery in the current treatment of gastric carcinoma

Surgery currently is the only curative option in the treatment of gastric cancer. For early gastric cancer, an endoscopic mucosal resection (EMR) is adequate for intramucosal cancer less than 2 cm in diameter without ulcer. For early cancers ineligible for EMR, limited surgical operation (proximal gastrectomy, segmental resection, and pylorus-preserving distal gastrectomy) can be recommended to reduce surgical risk and achieve improvements in quality of life without decreasing survival. Subtotal/total gastrectomy plus D2 lymph node dissection is the standard surgery for advanced gastric cancer in Japan. Pancreas-preserving total gastrectomy is recommended due to the reduced risk of pancreatic fistula and postoperative diabetes. Regarding extended surgery, results of a phase III study to evaluate the role of paraaortic node dissection will be analyzed in a few years' time after the accrual of more than 500 patients in a Japan Clinical Oncology Group (JCOG) study. For scirrhous gastric cancer, left upper abdominal exenteration appears to be associated with improved survival and should be tested in another controlled trial.

Pathophysiological studies on the relationship between postgastrectomy syndrome and gastric emptying function at 5 years after pylorus-preserving distal gastrectomy for early gastric cancer

Pylorus-preserving distal gastrectomy (PPG) has frequently been performed on patients with early gastric cancer in Japan to prevent the postgastrectomy syndrome seen after conventional distal gastrectomy (CDG). The long-term postoperative quality of life (QOL) and gastric emptying function in patients after PPG has not been assessed in detail. To clarify the usefulness of PPG for treating early gastric cancer we investigated the relation between postgastrectomy syndrome and gastric emptying function 5 years after PPG and then compared the results with those 5 years after CDG. Altogether, 32 patients who underwent curative gastrectomy at our clinic for early gastric cancer (submucosal cancer without lymph node metastasis) were studied. Ten subjects who underwent PPG with D2 lymphadenectomy without preserving the hepatic and pyloric branches of the vagal nerve [group A: eight men, two women; age 33-70 years (mean 60.7 years)] were interviewed and asked about appetite, weight loss, epigastric fullness, reflux esophagitis, and early dumping syndrome. They were compared with patients after CDG [group B: 36-72 years (mean 63.6 years)]. Esophagogastric endoscopy, abdominal ultrasonography, and gastric emptying function were also studied. The gastric emptying time of a semisolid diet was measured with a radioisotope method using (99m)Tc-labeled rice gruel; the gastric emptying time of a liquid diet was measured with the acetaminophen method using orange juice. The control subjects (group C) consisted of 18 healthy volunteers (10 men, 8 women) without gastrointestinal symptoms aged 38 to 68 years (mean 60.8 years). The following results were obtained: PPG (group A) alleviated postoperative gastrointestinal symptoms such as appetite loss, reflux esophagitis, early dumping syndrome, lost body weight, endoscopic reflux esophagitis, endoscopic gastritis in the remnant stomach, and postogastrectomy cholecystolithiasis better than did CDG (group B). The only weak point with the PPG procedure was that it produced a feeling of epigastric fullness. The pattern of the gastric emptying curve for the semisolid diet was almost the same among groups A, B, and C, although delayed gastric emptying was clearly more frequent in group A than in group B or C ( p < 0.05). Gastric emptying with the liquid diet in group B was significantly faster than that in groups A and C ( p < 0.01). Gastric emptying in groups A and C was similar. These results showed that PPG improved the postoperative QOL, but the delayed emptying of semisolid diet after PPG led to a feeling of epigastric fullness after meals due to retention of contents in the residual stomach. Epigastric fullness after meals continued in many patients after PPG. Thus the only disadvantage of the PPG procedure is the sensation of epigastric fullness and gastric stasis due to delayed gastric emptying of a semisolid diet.

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.

Studies of 13C-urea breath test for diagnosis of Helicobacter pylori infection in patients after partial gastrectomy

BACKGROUND/AIMS

Many of the reports on the diagnostic efficacy of the 13C-urea breath test (13C-UBT) for the detection of Helicobacter pylori in the residual stomach have shown negative results. We conducted an evaluation to establish a standardized protocol and an appropriate cutoff value for 13C-UBT in partial gastrectomy patients.

METHODS

Forty-two patients undergoing partial gastrectomy were included. Three gastric biopsies from the anastomotic site and mid-to-high body were taken at panendoscopy for histology, culture and rapid urease test (RUT). The 13C-UBT protocol included ingestion of 100 mg 13C-urea, use of mouthwash, and the body in a horizontal position on the left side. Six breath samples were taken after ingestion.

RESULTS

The Delta 13CO2 values were significantly elevated in infected patients at all time points, and values were higher at 20 min and thereafter than at an earlier time point. The sensitivity of 13C-UBT was 96.3% with the cutoff of 2.0 per thousand at 40 min. The accuracy rates were highest with 13C-UBT, culture, RUT and histological tests, in that order.

CONCLUSION

Forty minutes and a cutoff of 2.0 per thousand were found to be optimal for the test, with the body position horizontal on the left side. In the present protocol 13C-UBT appears to be a reliable tool with the same accuracy rate as other routine tests in patients with a remnant stomach.

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.

Functional characteristics of the pylorus in patients undergoing pylorus--preserving gastrectomy for early gastric cancer

BACKGROUND

This study investigates the functional characteristics of the pylorus in patients undergoing pylorus-preserving gastrectomy (PPG) for early gastric cancer.

METHODS

In study 1, postprandial symptoms and gastric emptying were compared between 2 groups of 12 patients with early gastric cancer more than 1 year after either PPG (PPG group) or distal gastrectomy (DG) (DG group). Gastric emptying was evaluated with the dual isotope technique for liquids and solids separately. In study 2, pyloric motility was evaluated with a sleeve/sidehole manometric assembly in 7 patients undergoing PPG, which was compared with that in the preoperative patients.

RESULTS

In study 1, the overall modified Visick score of postprandial symptoms and the Sigstad dumping score were significantly lower in the PPG group compared with the DG group (P <.05). Early accelerated gastric emptying was observed in both groups for liquids, but only in the DG group for solids. In study 2, isolated pyloric pressure waves induced by intraduodenal lipid infusion and phase III-like activity induced by intravenous erythromycin infusion were preserved after PPG.

CONCLUSIONS

The quantitative analysis of postoperative symptoms revealed that PPG patients were associated with better clinical conditions than DG patients. The clinical benefits of PPG are considered to be based on the function of the preserved pylorus.

Results of local resection with regional lymphadenectomy for early gastric cancer

BACKGROUND

In 1999, the authors reported preliminary results of local resection with regional lymphadenectomy(LR) for early gastric cancer.

METHODS

Twenty-four patients underwent LR until May 2000. Laparoscopic techniques were recently applied. The dissected area for lymphadenectomy depended on the lymphatic flow from the tumor. Local gastric resection was performed with a 2 cm cancer-free margin. Among the 24 patients, 14 who had been followed up for more than 1 year were eligible for the nutritional study, and the nutritional parameters were compared with those for patients undergoing pylorus-preserving gastrectomy (PPG).

RESULTS

Twenty-two patients not receiving additional gastrectomy needed no restriction of food intake and had neither postgastrectomy symptoms nor recurrence. All nutritional parameters remained stable between the preoperative and the subsequent period. Nutritional superiority of LR over PPG was observed.

CONCLUSIONS

For selected patients with early gastric cancer, LR can be a treatment of choice to provide a good quality of life.

Wider indications for the local resection of gastric cancer by adjacent lymphadenectomy

BACKGROUND AND OBJECTIVES

A variety of minimal invasive treatment strategies for early gastric cancer without reducing the curability have been introduced, however, the indications for the local resection of early gastric cancer have not been precisely established.

METHODS

Two approaches are adopted in this study to elucidate indications for local resection. One is a retrospective review of surgically resected, postoperatively histologically proven early gastric cancers between 1976 and 1996 (611 patients), and the other is the patient selection from those who underwent modified D(1) lymphadenectomy in a prospective manner between 1987 and 1996, based on the preoperative and intraoperative diagnoses of mucosal, node negative, nonpalpable gastric cancer (125 patients). In these approaches, patterns of nodal involvement in association with clinicopathological characteristics of gastric cancer were investigated.

RESULTS

The depressed with ulceration type and histologically high grade type were predominant characteristics of mucosal, node positive gastric cancer patients. Of these patients, after the exclusion of those who were diagnosed to have submucosal or advanced cancer preoperatively or who had palpable cancer intraoperatively, the gastric cancer < or =4 cm in maximum diameter had positive nodes confined to only one station adjacent to the cancer without simultaneous nodal involvement in the other stations.

CONCLUSIONS

Local resection can be performed for gastric cancers < or = 4 cm in maximum diameter that meet our criteria for modified D(1) lymphadenectomy, in association with the frozen section confirmation of cancer negative in the simultaneously dissected lymph nodes in the stations adjacent to the cancer. The adjacent lymphadenectomy and frozen section examination make the application of local resection possible for a wider segment of patients.

Current status and future perspectives in gastric cancer management

Gastric cancer is still a major health problem and a leading cause of cancer mortality despite a worldwide decline in incidence. Environmental and Helicobacter pylori (Hp) acting early in life in a multistep and multifactorial process may cause intestinal type carcinomas, whereas genetic abnormalities are related more to the diffuse type of disease. Primarily due to early detection of the disease, the results of treatment for gastric cancer have improved in Japan, Korea and several specialized Western centres. Surgery offers excellent long-term survival results for early gastric cancer (EGC). Advances in diagnostic and treatment technology have contributed to a trend towards minimal invasive surgery such as endoscopic mucosal resection (EMR) and laparoscopic surgery for selected mucosal cancers. In the Western world, however, more than 80% of patients at diagnosis have an advanced gastric cancer with a poor prognosis. The aim of surgery is complete removal of the tumour (UICC R0-resection), which is known to be the only proven, effective treatment modality and the most important treatment-related prognostic factor. Gastrectomy with preservation of the spleen and pancreas in most cases is the standard procedure. However, at present there is no consensus about the optimal extent of lymph-node dissection. The hypothesis that extended (D2) lymph-node dissection leads to improved survival has not been confirmed in randomized trials. Results from specialized centres and ongoing multi-institutional randomized trials, however, indicate that D2 dissection, with preservation of the spleen and pancreas, can be performed with the same safety as a D1 dissection. Furthermore, in 50% of patients with node-positive disease, the extraperigastric N2 nodes are involved (N2 disease) and thus an R0-resection is achievable only by a D2 node dissection resulting in a 5-year survival of about 30% for such patients. However, even after a D2 node dissection with curative potential, disease recurs in two-thirds of patients with locally advanced gastric cancer (LAGC) and is rapidly fatal. The need for an adjuvant treatment is obvious, but at present there is no such treatment of proven effectiveness. Promising results with preoperative chemotherapy, which increases the R0-resection rate, and intra-or early postoperative intraperitoneal chemohyperthermia to prevent peritoneal dissemination have been reported. However, randomized trials are necessary before these combined treatments become widely accepted. Present data indicate that the treatment of gastric cancer has become more and more sophisticated with a tailored therapy for individual cases. Treatment includes a broad spectrum of therapeutic options from EMR for selected mucosal cancers to aggressive combined treatment for LAGC. Precise knowledge of patterns of recurrence and metastases, critical evaluation of clinicopathologic variables, integration of high technology into diagnosis to predict accurately pre-treatment staging, and the surgeon's ability to perform minimally invasive surgery and D2 node dissection technique are necessary for an appropriate treatment option. All these prerequisites are best ensured by management in experienced surgical oncology units.

Surgical intervention and understanding of diseases of the stomach and duodenum

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

Dual roles of peptic ulcer in the carcinogenesis or extension of early gastric cancer

BACKGROUND

Early gastric cancer (EGC) often coexists with peptic ulcer. In this study we investigated the roles of peptic ulcer in the carcinogenesis and extension of gastric cancer.

METHODS

The clinicopathological characteristics of EGC and peptic ulcer and their relationship, as well as that of the background intestinal metaplasia, were compared among the following three groups: patients with peptic ulcer only inside the EGC (Contained group, 53 patients); patients with peptic ulcer only outside the EGC (Separate group, 26 patients); and patients of EGC with no peptic ulcer (Absent group, 43 patients).

RESULTS

In the Separate group, a male preponderance was observed (P = .006), and all EGCs developed in the middle or lower third of the stomach (P = .06). Most of the EGCs were an intestinal type of cancer with severe background intestinal metaplasia. Topographically, 88% of the peptic ulcers in the Separate group developed proximal to the EGC. On the other hand, in the Contained group, most EGCs developed in the middle third of the stomach with an intestinal/diffuse type ratio of 1:1. Peptic ulcers inside the EGC were significantly more shallow than those that developed outside the EGC (P = 0.008). Although the incidences of submucosal cancer were nearly the same among the three groups, the maximum cancer diameter tended to be increased in the Contained group compared to that in the Absent group, and the incidence of lymph node involvement tended to be higher in the Contained group (8%) as compared with the other two groups (4%-5%).

CONCLUSIONS

These results suggest that peptic ulcer outside the EGC contributes to the development of the intestinal type of EGC, with the background of more severe intestinal metaplasia during the peptic ulcer healing processes, whereas peptic ulcer inside the EGC develops secondary to EGC and favors cancer extension and metastasis. Peptic ulcer associated with EGC can be considered to exert different biological roles in the carcinogenesis or extension of ECG according to the location of the peptic ulcer.