Laparoscopy-assisted pylorus-preserving gastrectomy for early gastric cancer: A retrospective study of long-term functional outcomes and quality of life

BACKGROUND Laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) was known to have benefits of function-preserving surgery compared to laparoscopy-assisted distal gastrectomy (LADG). However, in clinical settings, delayed gastric emptying and esophageal reflux following LAPPG can be serious issues, making surgeons reluctant to perform LAPPG. It is unclear that LAPPG had better longterm functional outcomes and quality of life compared to LADG. AIM To evaluate the long-term functional outcomes and patient-reported quality of life of LAPPG compared to those of LADG. METHODS We reviewed the clinicopathological data of 195 patients who underwent LADG with Billroth II anastomosis and 101 patients who underwent LAPPG for cT1N0 gastric cancer in the middle third of the stomach between 2012 and 2015. Postoperative complications, nutritional parameters, and survey results of the European Organization for Research and Treatment of Cancer Questionnaire C30 and STO22 questionnaire were compared between the two groups. RESULTS The serum hemoglobin level was significantly higher in the LAPPG group than in the LADG group (P < 0.001). In the endoscopic findings, incidence of bile reflux was lower (P < 0.001);however, the incidence of residual food was higher in the LAPPG group than in the LADG group (P < 0.001). Regarding the quality of life score, the LAPPG group had a better physical functioning score (86.7 vs 90.0, P = 0.032) but also greater pain and reflux when compared to the LADG group [8.3 vs 16.7 in pain, 11.1 (interquartile range, 0, 22.2) vs 11.1 (interquartile range, 11.1, 33.3) in reflux, P = 0.034 and 0.001, respectively]. CONCLUSION LAPPG is beneficial to recovery of anemia and to bile reflux, however, it might be unfavorable in terms of pain and reflux symptoms compared to LADG with Billroth II anastomosis.

A comparative study of totally laparoscopic distal gastrectomy versus laparoscopic-assisted distal gastrectomy in gastric cancer patients: Short-term operative outcomes at a high-volume center

Objective： Laparoscopic gastrectomy has been established as a standard treatment for early gastric cancer, and its use is increasing recently. Compared with the conventional laparoscopy-assisted distal gastrectomy （LADG）, totally laparoscopic distal gastrectomy （TLDG） involves intracorporeal reconstruction, which can avoid the additional incision, resulting in pain reduction and early recovery. This study aimed to compare the short-term postoperative outcomes of TLDG vs. LADG in gastric cancer in a high-volume center.Methods： A retrospective cohort study was conducted on 1,322 patients who underwent laparoscopic distal gastrectomy from June 2012 to June 2017 at the National Cancer Center, Korea. LAD G was performed in the early period before July 2015, and TLDG was applied in the later period. Postoperative short-term outcomes were compared in terms of complication and clinical course between the two groups. Pain score was measured by rating the pain intensity from 0 to 10 points on postoperative day （POD） 1 and 3. Results： A total of 667 patients underwent LADG and 655 patients underwent TLDG. Clinieopathologic characteristics were not different in both groups. Intraoperative estimated blood loss （EBL） was significantly lower in the TLDG group （P〈0.001）. Postoperative pain scores were significantly lower in the TLDG group than in the LADG group on POD 1 （5.1±1.5 vs. 4.8±1.4, P=0.015）. First flatus passage after operation was significantly earlier in the TLDG group （3.4±0.8 d vs. 3.2±0.6 d, P〈0.001）. There were no differences in postoperative complications and hospital stay between the two groups. Conclusions： Based on the reported short-term postoperative outcomes, TLDG is safe and feasible as well as LADG. Moreover, compared with LADG, TLDG can reduce intraoperative EBL and postoperative pain and enhance the bowel motility in gastric cancer surgery.

Predictive value of E-cadherin and Ep CAM for detection of metastatic lymph node in early gastric cancer

Objective:There has been a demand for a tumor-specific marker for metastatic lymph nodes in sentinel navigation surgery for gastric cancer.The aim of this study is to analyze protein expression in both primary tumors and metastatic lymph nodes in early gastric cancer patients.Methods:We collected primary tumors and metastatic lymph nodes from 71 patients who underwent curative gastrectomy and pathologically diagnosed with T1 N1 or T1 N2(8 th Union for International Cancer Control 8 th edition/American Joint Committee on Cancer staging system)gastric cancer.Immunohistochemistry was used to determine the expression of six cell membrane proteins,including carcinoembryonic antigen(CEA),E-cadherin,epithelial cell adhesion molecule(Ep CAM),P-cadherin,CD44 v6,and c-erb B2 in the patient samples.Results:The expression of CEA,E-cadherin,Ep CAM,P-cadherin,CD44 v6 and c-erb B2 in the evaluable primary tumor samples was 75.4%,97.1%,100%,89.9%,11.1%and 7.2%,respectively.Among cases wherein both the primary tumor and metastatic lymph nodes were evaluable,double positivity(expression in both primary tumor and metastatic lymph nodes)was observed for CEA,E-cadherin,Ep CAM,P-cadherin,CD44 v6 and c-erb B2 in 53.2%,97.9%,98.1%,76.6%,0 and 6.8%of the cases,respectively.The proportion of metastatic lymph nodes positive for CEA,E-cadherin,Ep CAM,P-cadherin,CD44 v6 and c-erb B2 was 71.4%,100%,98.1%,83.7%,0,and75%,respectively in primary tumors positive for the same markers.Conclusions:E-cadherin and Ep CAM had an overlap of 100%and 98.1%between the primary tumor and metastatic lymph nodes,respectively.Thus,E-cadherin and Ep CAM are potential molecular markers to detect metastatic lymph nodes in patients with early gastric cancer.

Recent updates and current issues of sentinel node navigation surgery for early gastric cancer

With the increase in the incidence of early gastric cancer(EGC),several endoscopic and laparoscopic approaches,such as endoscopic submucosal dissection and function-preserving gastrectomy,have been accepted as standard treatments.Sentinel node navigation surgery(SNNS)is an ideal surgical option for preservation of most parts of the stomach and consequent maintenance of normal gastric function to improve quality of life in patients with EGC.Although many previous studies and clinical trials have demonstrated the safety and feasibility of the sentinel node concept in gastric cancer,the clinical application of SNNS is debatable.Several issues regarding technical standardization and oncological safety need to be resolved.Recently several studies to resolve these problems are being actively performed,and SNNS might be an important surgical option in the treatment of gastric cancer in the future.

Factors associated with metastasis in superior mesenteric vein lymph node in subtotal gastrectomy for gastric cancer:Retrospective case control study

Objective: The revised Japanese treatment guideline for gastric cancer recommends dissection of the superior mesenteric vein lymph node(No. 14v LN) if there is metastasis in infrapyloric lymph node(No. 6 LN). However,it is still controversial whether LN dissection is necessary. The aim of this study was to investigate the factors associated with metastasis in No. 14v LN.Methods: Patients who underwent D2 lymphadenectomy between 2003 and 2010 were included. We excluded patients who underwent total gastrectomy, had multiple lesions, or had missing data about the status of metastasis in the LNs that were included in D2 lymphadenectomy. Clinicopathologic characteristics and the metastasis in regional LNs were compared between patients with No. 14v LN metastasis(14v+) and those without(14v-).Results: Five hundred sixty patients were included in this study. Univariate analysis showed that old age, larger tumor size, tumor location, differentiation, lymphatic invasion, venous invasion, perineural invasion, T classification, and N classification were related to metastasis in No. 14v LN. Multivariate analysis showed differentiation(P=0.027) and N classification(P<0.001) were independent related factors. Metastasis in infrapyloric lymph node(No. 6 LN) and proxiaml splenic lymph node(No. 11p LN) was independently associated with metastasis in No. 14v LN.Conclusions: Differentiation and N classification were independent factors associated with No. 14v LN metastasis, and No. 6 and No. 11p LN metastasis were independent risk factors for No. 14v LN metastasis.

Current status and challenges in sentinel node navigation surgery for early gastric cancer

Although a number of feasibility studies for sentinel node （SN） concepts in gastric cancer have been conducted since 2000, there remains a debate regarding detailed detection techniques and oncological safety. Two important multicenter phase II clinical trials were performed in Japan that used different methods and reached different conclusions; one confirmed acceptable results with a false-negative rate of 7%, and the other showed an unacceptably high false-negative rate of 46.4%. The Sentinel Node Oriented Tailored Approach （SENORITA） trial is a multicenter randomized controlled phase 1/I trial being performed in Korea. Patient enrollment is now complete and the long-term results are currently awaited. Recently, an image-guided SN mapping technique using infrared ray/fluorescence was introduced. This method might be a promising technology because it allows the clear visualization of SNs. With regard to the primary tumor, the non-exposed endoscopic wall-inversion surgery technique and non-exposure endolaparoscopic full-thickness resection with simple suturing technique have been reported. These methods prevent abdominal infection and tumor seeding and can be good alternatives to conventional laparoscopic gastric wedge resection. For indications, SN navigation surgery can be extended to patients who underwent non-curative endoscopic resection. Although a few studies have been performed on these patients, sentinel concepts may be beneficial to patients as they omit the need for additional gastrectomy. SN navigation surgery can lead to actual organ-preserving surgery and plays a key role in improving the quality of life of patients with early gastric cancer in the future.

Gastric cancer surgery in South Korea: Past, present, and future

Gastric cancer remains a significant global health concern and its surgical management approaches have undergone significant changes in South Korea and worldwide. Subtotal or total gastrectomy with D2 lymph node dissection is well established as a standard surgical procedure for gastric cancer. With the active implementation of cancer screening in South Korea, the proportion of early gastric cancer cases has significantly increased over the past few decades, leading to a steady increase in the survival rate among patients. Furthermore, recent advances in surgical instruments and techniques have made minimally invasive surgery increasingly prevalent, not only for early but also for advanced gastric cancer. We aim to provide a comprehensive overview of the evolution and current status of gastric cancer surgery in South Korea.

Individual having a parent with early-onset gastric cancer may need screening at younger age

AIM: To evaluate whether individuals with gastric cancer(GC) are diagnosed earlier if they have firstdegree relatives with GC.METHODS: A total of 4282 patients diagnosed with GC at National Cancer Center Hospital from 2002 to 2012 were enrolled in this retrospective study. We classified the patients according to presence or absence of first-degree family history of GC and compared age at diagnosis and clinicopathologic characteristics. In addition, we further classified patients according to specific family member with GC(father, mother, sibling, or offspring) and compared age at GC diagnosis among these patient groups. Baseline characteristics were obtained from a prospectively collected database. Information about the family member's age at GC diagnosis was obtained by questionnaire.RESULTS: A total of 924 patients(21.6%) had a firstdegree family history of GC. The mean age at GC diagnosis in patients having paternal history of GC was 54.4 ± 10.4 years and was significantly younger than in those without a first-degree family history(58.1 ± 12.0 years, P < 0.001). However, this finding was not observed in patients who had an affected mother(57.2 ± 10.0 years) or sibling(62.2 ± 9.8 years). Among patients with family member having early-onset GC(< 50 years old), mean age at diagnosis was 47.7 ± 10.3 years for those with an affected father, 48.6 ± 10.4 years for those with an affected mother, and 57.4 ± 11.5 years for those with an affected sibling. Thus, patients with a parent diagnosed before 50 years of age developed GC 10.4 or 9.5 years earlier than individuals without a family history of GC(both P <0.001).CONCLUSION: Early-onset GC before age of 50 was associated with parental history of early-onset of GC. Individual having such family history need to start screening earlier.

Effect of dietary vitamin C on gastric cancer risk in the Korean population

AIM: To investigate the effects of dietary vitamin C and foods containing vitamin C on gastric cancer risk.METHODS: Our study included 830 control subjects and 415 patients. Data regarding demographics, medical history, and lifestyle, including dietary and nutrient intake, were collected using reliable selfadministered questionnaires. Dietary intake information was collected from the participants using a food frequency questionnaire that has been previously reported as reliable and valid. A rapid urease test and a histological evaluation were used to determine the presence of Helicobacter pylori(H. pylori) infection. Twenty-three vitamin C-contributing foods were selected, representing over 80% of the cumulative vitamin C contribution. RESULTS: In analyses adjusted for first-degree family history of gastric cancer, education level, job, household income, smoking status, and regular exercise, an inverseassociation between vitamin C intake and gastric cancer risk was observed for the highest(≥ 120.67 mg/d) vs the lowest(< 80.14 mg/d) intake category [OR(95%CI): 0.64(0.46-0.88)], with a significant trend across the three intake categories(P = 0.007). No protective effect of vitamin C was detected after stratification by gender. No effect of vitamin C intake on the gastric cancer incidence was found in either men or women infected with H. pylori. Vitamin C-contributing foods, including cabbage [0.45(0.32-0.63), 0.50(0.34-0.75), 0.45(0.25-0.81)], strawberries [0.56(0.40-0.78), 0.49(0.32-0.74), 0.52(0.29-0.93)], and bananas [0.40(0.29-0.57), 0.41(0.27-0.62), 0.34(0.19-0.63)], were protective factors against the risk of gastric cancer based on the results of the overall adjusted analyses and the results for men and women, respectively.CONCLUSION: A protective effect of vitamin C and vitamin C-contributing foods against gastric cancer was observed. Further studies using larger sample sizes are required to replicate our results.

Gastric choriocarcinoma admixed with an α-fetoprotein-producing adenocarcinoma and separated adenocarcinoma

We report a case of gastric choriocarcinoma admixed with an α-fetoprotein (AFP)-producing adeno-carcinoma. A 70-year-old man was hospitalized for gastric cancer that was detected during screening by esophagogastroduodenoscopy (EGD). Initial laboratory data showed the increased serum level of AFP and EGD revealed a 5-cm ulcerofungating mass in the greater curvature of the gastric antrum. The patient underwent radical subtotal gastrectomywith D2 lymph node dissection and Billroth gastrojejunostomy. Histopathological evaluation confirmed double primary gastric cancer: gastric choriocarcinoma admixed with an AFP-producing adenocarcinoma and separated adenocarcinoma. At 2 wk postoperatively, his human chorionic gonadotropin and AFP levels had reduced and six cycles of adjuvant chemotherapy were initiated. No recurrence or distant metastasis was observed at 4 years postoperatively.

Effects of different Helicobacter pylori culture filtrates on growth of gastric epithelial cells

AIM:To study the effects of different Helicobacter pylori(H pylori) culture filtrates on growth of gastric epithelial cells. METHODS:Broth culture filtrates of H pylori were prepared. Gastric epithelial cells were treated with the filtrates,and cell growth was determined by growth curve and flow cytometry. DNA damage of gastric epithelial cells was measured by single-cell microgel electrophoresis. RESULTS:Gastric epithelial cells proliferated actively when treated by CagA-gene-positive broth culture filtrates,and colony formation reached 40%. The number of cells in S phase increased compared to controls. Comet assay showed 41.2% comet cells in GES-1 cells treated with CagA-positive filtrates(P < 0.05) . CONCLUSION:CagA-positive filtrates enhance the changes in morphology and growth characteristics of human gastric epithelial tumor cells. DNA damage maybe one of the mechanisms involved in the growth changes.

采用环形黏膜切口的内镜下黏膜切除术治疗黏膜内胃肿瘤的经验曲线

Background: EMR with circumferential mucosal incision facilitates en bloc resection, which is the most important predictor for complete resection in the treatment of intramucosal gastric neoplasm. The objective of the study was to evaluate the efficacy and the safety of EMR with circumferential mucosal incision in re lation to the endoscopist‘s experience. Methods: In this retrospective study, w e analyzed the outcome of 80 EMR procedures performed by a single endoscopist at the National Cancer Center, Goyang, Korea. The EMR procedure with circumferenti al mucosal incision was performed with a conventional needle knife. We compared the en bloc resection rate, the complete resection rate, the duration of the pro cedure time, and the associated complications by quartiles. Results: From the fi rst to the last quartile, en bloc resection rates were 55%, 45%, 85%, and 85 %(p = 0.006), and complete resection rates were 65%, 60%, 90%, and 85%(p = 0.039) . The increase in the mean en bloc and complete resection rates between t he first two quartiles and the second two quartiles was significant (p = 0.002 a nd p = 0.019, respectively). Three perforations (15%) were reported in the firs t qua rtile and only one (1.7%) in the remaining 3 quartiles (p = 0.046) . The proced ure time also decreased after the first 20 cases (p = 0.004). Conclusions: For a n experienced endoscopist, EMR with circumferential mucosal incision could be pe rformed effectively and safely after the experience of 40 cases.