Korean Practice Guidelines for Gastric Cancer 2022: An Evidence-based, Multidisciplinary Approach

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Intraoperative tumor localization using a titanium ring strip in totally laparoscopic distal gastrectomy for middle-third gastric cancer / 고신대학교의과대학학술지

Background@#This study presents a novel technical tip for intraoperative tumor localization and determination of the proximal resection line using a titanium ring strip for totally laparoscopic distal gastrectomy in patients with middle-third gastric cancer and describes the short-term results of its application. @*Methods@#In total, 42 patients with middle-third gastric cancer who underwent intraoperative tumor localization using a titanium ring strip and determination of the proximal resection line through intraoperative radiography between January 2020 and December 2021 were enrolled in this study. We retrospectively analyzed patients’ prospectively collected clinical, pathological, and surgical data. @*Results@#Twenty-six men and 16 women with a mean age of 58.3±12.5 years were enrolled. The mean operation time and estimated blood loss were 212.6±43.0 minutes and 122.4±77.6 mL, respectively. The lengths of the proximal and distal resection margin were 2.0±0.4 cm (range, 0.8–3.7 cm) and 10.5±4.1 cm (range, 0.4–20.4 cm), respectively. Roux-en-Y anastomosis was performed in 30 patients, while Billroth II with Braun anastomosis was performed in 12 patients. There were no procedure-related complications, and the mean postoperative hospital stay was 7.2±1.9 days. For all patients, the negative proximal resection margin was confirmed by postoperative pathological examinations. @*Conclusions@#Intraoperative tumor localization and determination of the proximal resection line using a titanium ring strip is a useful alternative method that can be easily and safely performed. This method is especially useful for patients with middle-third gastric cancer requiring an appropriate proximal resection margin.

Clinical features of internal hernia after gastrectomy for gastric cancer

Purpose@#Internal hernia after gastrectomy is a rare but potentially life-threatening condition without surgical intervention. Clinical risk factors of internal hernia should, hence, be reviewed after gastrectomy.From 2008 to 2018, patients who underwent gastrectomy for gastric cancer were investigated. @*Methods@#Abdominal computed tomography (CT) was used to screen for internal hernia, and surgical exploration was performed to confirm the diagnosis. Using retrospective statistical analysis, the incidence, characteristics, and risk factors were identified, and the characteristics of the internal hernia group were reviewed. @*Results@#The overall incidence of internal hernia was 0.9%. From statistical analysis, it was found that laparoscopic surgery was almost five times riskier than open gastrectomy (odds ratio [OR], 4.947; 95% confidence interval [CI], 1.308–18.710; p = 0.019). Body mass index < 25 kg/m2 (OR, 4.596; 95% CI, 1.056– 20.004; p = 0.042) and proximal gastrectomy (OR, 4.238; 95% CI, 1.072–16.751; p = 0.039) were also associated with internal hernia. Among 20 patients with internal hernia, 12 underwent laparotomy, and five had their bowels removed due to ischemia. All patients with bowel resected had suffered from short bowel syndrome. @*Conclusion@#Suspecting an internal hernia should be an important step when a patient with a history of laparoscopic gastrectomy visits for medical care. When suspected, emergent screening through CT scan and surgical intervention should be considered as soon as possible to prevent lifetime complications accordingly.

Reduction rate of C-reactive protein as an early predictor of postoperative complications and a reliable discharge indicator after gastrectomy for gastric cancer

PURPOSE: Postoperative complications (PCs) after gastrectomy are associated with readmission and longer hospital stay. This study aimed to determine the role of CRP as an early predictor of PCs and a reliable discharge indicator after gastrectomy. METHODS: Clinicopathologic data and PCs of 613 patients who underwent gastrectomy for gastric cancer in 2015–2016 were retrospectively analyzed, including consecutive blood samples for CRP obtained preoperatively, at the operative day, and postoperatively. Following the Clavien-Dindo classification, the patients were divided into a group with major PCs and a group with minor/no PCs. Diagnostic accuracy was determined by the area under the receiver operating characteristic curve (AUC). Clinical factors related to major PCs were identified using univariate and multivariate logistic regression analyses. RESULTS: PCs occurred in 89 patients (14.5%). The most significant predictive factor for major PCs was a CRP concentration reduction rate of ≤38.1% (AUC, 0.82; sensitivity, 76.4%; specificity, 76.1%) between postoperative day (POD) 3 and 5 (R5), followed by ≤11.1% (AUC, 0.75; sensitivity, 73%; specificity, 76%) between POD 2 and 3 (R4). When both factors were applied (R4 ≤ 11.1% and R5 ≤ 38.1%), the specificity was 91.6%; when only one condition was satisfied (R4 ≤ 11.1% or R5 ≤ 38.1%), the sensitivity was 91%. CONCLUSION: CRP concentration reduction rates between POD 3 and 5 and between POD 2 and 3 were the best combination factors to predict PCs and indicate a safe discharge after gastrectomy for gastric cancer.

Common Hepatic Artery Originating from Left Gastric Artery: A Rare Variant Encountered in Gastric Cancer Surgery / 고신대학교의과대학학술지

The hepatic artery can have numerous variations. However, a common hepatic artery originating from the left gastric artery and the entire hepatic blood supply furnished by the left gastric artery is an extremely rare anomaly. We encountered this anomaly in a patient with advanced gastric cancer. A surgeon should recognize this image appearance and identify the anomaly. Without knowledge of this anomaly and given the strategy for extensive lesser sac dissection generally employed during gastric cancer surgery, a surgeon could easily inadvertently divide this vessel, resulting in critical liver damage. We report a case of common hepatic artery originating from left gastric artery and review of the literatures.

Analysis of Postoperative Complications Following Laparoscopic Gastrectomy in 1332 Gastric Cancer Patients

PURPOSE: To analyze postoperative complications for gastric cancer patients undergoing laparoscopic gastrectomy in single institution over long period of time. METHODS: The data of 1332 consecutive patients undergoing laparoscopic gastrectomy for gastric cancer at a single institution from January 2007 to December 2015 were reviewed. The patients were classified into the early or late surgery group; the initial 100 cases were classified as the initial group. We compared between the two groups and analyzed risk factors for postoperative complications. RESULTS: A total of 265 postoperative complications occurred in 223 patients (16.7%). Major complications occurred in 38 patients (2.9%) including 1 death (0.1%). Operative time and hospital stay were significantly shorter in the late group. Blood loss was greater in the initial group. Sex, comorbidity, tumor location, D2 LND, operative method, non B-I anastomosis, co-resection, long operative time, and blood loss were significant risk factors for overall postoperative complication. In the multivariate analysis, male sex, comorbidity, D2 lymph node dissection, total or proximal gastrectomy, non B-I anastomosis, co-resection, operative time and blood loss were associated with postoperative overall complications. CONCLUSION: Sex, co-morbidity, D2 LND, operative method, co-resection, operative time and blood loss revealed as the risk factor of overall postoperative complication. And there was no significant differences of risk factor related to postoperative complication between initial and maturation surgical period. This suggests that beginners also can safely perform laparoscopic gastrectomy through the appropriate patient selection.

Erratum to: Complications and Survival Rate of Patients Over 80 Years Old Who Underwent Laparoscopic Gastrectomy for Gastric Cancer

Authors requested to change the name of the hospital to proper name.

Complications and Survival Rate of Patients Over 80 Years Old Who Underwent Laparoscopic Gastrectomy for Gastric Cancer

PURPOSE: As the life expectancy increases, the population of elderly patients increases. We evaluated the complications and survival rate of patients over 80 years old, who underwent laparoscopic gastrectomy. METHODS: A retrospective analysis was conducted for a total of 1,912 patients, who underwent surgery with stomach cancer from 2008 to 2016. We analyzed postoperative complications and the survival rate between the middle old (70~79, n=255) group and the very old (≥80, n=37) group. RESULTS: Among 1,912 patients, 255 people in the middle old group and 37 people within the very old group underwent laparoscopic gastrectomy. We confirmed that there was no significant difference except for the age (p<0.001) between the two groups. Overall complications were not statistically significantly different between the Middle old (70~79) group and the very old (≥80) group, 11.8% and 16.2%, respectively. There were also no statistically significant differences in severe complications beyond Clavien-Dindo classification Grade III. Risk factors for overall complications were higher in males than in females (p=0.002). Overall survival was statistically significantly lower with very old group (p<0.001). CONCLUSION: Laparoscopic gastrectomy in gastric cancer patients over 80 years of age is feasible and safe in terms of complications. However, considering the life expectancy, it seems necessary to pay attention to the patients who apply surgery.

Risk factors for lymph node metastasis in mucosal gastric cancer and re-evaluation of endoscopic submucosal dissection

PURPOSE: The selection of the appropriate treatment strategy for patients with mucosal gastric cancer (MGC) remains controversial. In the present study, we aimed to determine the risk factors for lymph node (LN) metastasis in MGC and reassess the role of endoscopic submucosal dissection (ESD). METHODS: We examined 1,191 MGC patients who underwent curative gastrectomy between January 2005 and December 2014. We determined the clinicopathologic risk factors for LN metastasis among the MGC patients. RESULTS: Among 1,191 patients with MGC, 42 patients (3.5%) had LN metastasis. Univariate analysis indicated that age ≤ 50 years (P = 0.045), tumor invasion to the muscularis mucosa (P 2 cm (P = 0.014), presence of ulceration (P = 0.01), diffuse type as per Lauren classification (P = 0.005), and undifferentiated-type histology (P = 0.001) were associated with LN metastasis. Moreover, multivariate analysis indicated that tumor invasion to the muscularis mucosa (P = 0.001; odds ratio [OR], 4.909), presence of ulceration (P = 0.036; OR, 1.982), and undifferentiated-type histology (P = 0.025; OR, 4.233) were independent risk factors for LN metastasis. In particular, LN metastasis was observed in some MGC cases with indications for ESD, including absolute indications (1 of 179, 0.6%) and expanded indications (9 of 493, 1.8%). CONCLUSION: Although MGC patients can be treated via ESD, we recommend that they undergo a more aggressive treatment strategy if they have tumor invasion to the muscularis mucosa, ulceration, or undifferentiated-type histology in the final pathology report.

Risk factors for lymph node metastasis in mucosal gastric cancer and re-evaluation of endoscopic submucosal dissection

PURPOSE: The selection of the appropriate treatment strategy for patients with mucosal gastric cancer (MGC) remains controversial. In the present study, we aimed to determine the risk factors for lymph node (LN) metastasis in MGC and reassess the role of endoscopic submucosal dissection (ESD). METHODS: We examined 1,191 MGC patients who underwent curative gastrectomy between January 2005 and December 2014. We determined the clinicopathologic risk factors for LN metastasis among the MGC patients. RESULTS: Among 1,191 patients with MGC, 42 patients (3.5%) had LN metastasis. Univariate analysis indicated that age ≤ 50 years (P = 0.045), tumor invasion to the muscularis mucosa (P 2 cm (P = 0.014), presence of ulceration (P = 0.01), diffuse type as per Lauren classification (P = 0.005), and undifferentiated-type histology (P = 0.001) were associated with LN metastasis. Moreover, multivariate analysis indicated that tumor invasion to the muscularis mucosa (P = 0.001; odds ratio [OR], 4.909), presence of ulceration (P = 0.036; OR, 1.982), and undifferentiated-type histology (P = 0.025; OR, 4.233) were independent risk factors for LN metastasis. In particular, LN metastasis was observed in some MGC cases with indications for ESD, including absolute indications (1 of 179, 0.6%) and expanded indications (9 of 493, 1.8%). CONCLUSION: Although MGC patients can be treated via ESD, we recommend that they undergo a more aggressive treatment strategy if they have tumor invasion to the muscularis mucosa, ulceration, or undifferentiated-type histology in the final pathology report.

Necrotizing soft tissue infection: analysis of the factors related to mortality in 30 cases of a single institution for 5 years

PURPOSE: Necrotizing soft tissue infection is the infection of the soft tissue with necrotic changes. It is rare, but results in high mortality. We analyzed the characteristics of patients, prognosis, and mortality factors after reviewing 30 cases of a single hospital for 5 years. METHODS: From January 2009 to December 2013, 30 patients diagnosed with necrotizing fasciitis or Fournier's gangrene in Pusan National University Hospital were enrolled for this study. The following parameters were analyzed retrospectively: demographics, infection site, initial laboratory finding, initial antibiotics, isolated microorganisms, number of surgeries, time to first operation, length of intensive care unit, and total hospital stays. RESULTS: The overall mortality rate was 23.3%. Mean body mass index (BMI) of the survival group (24.7 ± 5.0 kg/m2) was significantly higher than the nonsurvival group (22.0 ± 1.4 kg/m2, P = 0.029). When BMI was less than 23 kg/m2, the mortality rate was significantly higher (P = 0.025). Two patients (6.7%) with chronic kidney disease requiring hemodialysis died (P = 0.048). Initial WBC count (>13×103/µL), CRP (>26.5 mg/dL), and platelet (PLT) count (27.6 mg/dL), serum creatinine (>1.2 mg/dL) that reflected kidney function were significant mortality factors. CONCLUSION: Patients with low BMI or abnormal values of WBC count, CRP, and PLT count reflecting the degree of infection or abnormal renal function will need more intensive care.

Necrotizing soft tissue infection: analysis of the factors related to mortality in 30 cases of a single institution for 5 years

PURPOSE: Necrotizing soft tissue infection is the infection of the soft tissue with necrotic changes. It is rare, but results in high mortality. We analyzed the characteristics of patients, prognosis, and mortality factors after reviewing 30 cases of a single hospital for 5 years. METHODS: From January 2009 to December 2013, 30 patients diagnosed with necrotizing fasciitis or Fournier's gangrene in Pusan National University Hospital were enrolled for this study. The following parameters were analyzed retrospectively: demographics, infection site, initial laboratory finding, initial antibiotics, isolated microorganisms, number of surgeries, time to first operation, length of intensive care unit, and total hospital stays. RESULTS: The overall mortality rate was 23.3%. Mean body mass index (BMI) of the survival group (24.7 ± 5.0 kg/m2) was significantly higher than the nonsurvival group (22.0 ± 1.4 kg/m2, P = 0.029). When BMI was less than 23 kg/m2, the mortality rate was significantly higher (P = 0.025). Two patients (6.7%) with chronic kidney disease requiring hemodialysis died (P = 0.048). Initial WBC count (>13×103/µL), CRP (>26.5 mg/dL), and platelet (PLT) count (27.6 mg/dL), serum creatinine (>1.2 mg/dL) that reflected kidney function were significant mortality factors. CONCLUSION: Patients with low BMI or abnormal values of WBC count, CRP, and PLT count reflecting the degree of infection or abnormal renal function will need more intensive care.

Duodenal stump fistula after gastrectomy for gastric cancer: risk factors, prevention, and management

PURPOSE: A duodenal stump fistula is one of the most severe complications after gastrectomy for gastric cancer. We aimed to analyze the risk factors for this problem, and to identify the methods used for its prevention and management. METHODS: We retrospectively reviewed the clinical data of 716 consecutive patients who underwent curative gastrectomy with a duodenal stump for gastric cancer between 2008 and 2013. RESULTS: A duodenal stump fistula occurred in 16 patients (2.2%) and there were 2 deaths in this group. Univariate analysis revealed age >60 years (odds ratio [OR], 3.09; 95% confidence interval [CI], 0.99-9.66), multiple comorbidities (OR, 4.23; 95% CI, 1.50-11.92), clinical T stage (OR, 2.91; 95% CI, 1.045-8.10), and gastric outlet obstruction (OR, 8.64; 95% CI, 2.61-28.61) to be significant factors for developing a duodenal stump fistula. Multivariate analysis identified multiple comorbidities (OR, 3.92; 95% CI, 1.30-11.80) and gastric outlet obstruction (OR, 5.62; 95% CI, 1.45-21.71) as predictors of this complication. CONCLUSION: Multiple comorbidities and gastric outlet obstruction were the main risk factors for a duodenal stump fistula. Therefore, preventive methods and aggressive management should be applied for patients at high risk.

Evaluation of P-POSSUM as a Risk Prediction Model in Laparoscopic Gastrectomy of Elderly Patients with Gastric Cancer

PURPOSE: The physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM) is a validated scoring system for auditing surgical outcomes. However, evaluation of this system has primarily been applied to open surgical techniques. The present study demonstrates the validity of P-POSSUM in predicting morbidity and mortality in the treatment of elderly patients with gastric cancer who underwent curative laparoscopic gastrectomy. METHODS: All patients aged 70 years or over, who underwent curative laparoscopic gastrectomy between January 2014 and January 2015, were collected from our hospital database. A case-note review was used to collate data in terms of clinical and operative factors as described in P-POSSUM. Observed/Estimated ratio of morbidity and 30-day mortality were calculated. RESULTS: Laparoscopic gastrectomy was performed in 101 patients. The mean age was 74.9 years (70~83 years). A significant postoperative morbidity was observed in 20 (19.8%) of 101 patients. There was no 30-day mortality. Using exponential analysis, P-POSSUM predicted morbidity in 22 patients. Thus, O/E ratios for morbidity and mortality were 0.9 and 0, respectively. CONCLUSION: P-POSSUM scoring slightly overestimated predictions of morbidity and mortality. An assessment of its application to laparoscopic gastrectomy of elderly patients with gastric cancer merits further evaluation. Also, laparoscopic gastrectomy was a feasible and safe treatment for elderly patients in terms of P-POSSUM.

Effect of extramucin pools in gastric cancer patients

PURPOSE: Mucinous gastric adenocarcinoma (MGC) is defined by the World Health Organization as a gastric adenocarcinoma with >50% extracellular mucin pools within the tumors. In this study, we attempted to analyze the clinicopathologic features of patients pathologically diagnosed as gastric cancer with lower than 50% tumor volume of extracellular mucin pool adenocarcinoma (LEMPC). We compared MGC versus nonmucinous gastric adenocarcinoma (NMGC). We were used in abbreviations LEMPC for NMGC including extracellular mucin pool. METHODS: Files of 995 patients with gastric cancer NMGC (n = 935), MGC (n = 20), LEMPC (n = 40) who underwent curative resection at Pusan National University Yangsan Hospital from December 2008 to December 2013 were retrospectively analyzed. All pathologic reports after curative resection and evaluated clinicopathologic features were reviewed to identify the effect of extracellular mucin pools in gastric cancer. RESULTS: Compared with the NMGC patients, the clinicopathological features of MGC patients were as follows: more frequent open surgery, larger tumor size, more advanced T stage and N stage, more positive lymph node metastasis, and perineural invasion. LEMPC patients showed similar features compared with NMGC patients. MGC and LEMPC patients showed similar clinicopathological features, except T stage and lymph node metastasis. CONCLUSION: LEMPC can be thought of as a previous step of MGC. It is reasonable to consider LEMPC patients in the diagnostic criteria of MGC, and to adequately treat.

Single-incision intragastric resection for upper and mid gastric submucosal tumors: a case-series study

PURPOSE: Laparoscopic gastric wedge resection is a standard treatment for removing gastric submucosal tumors (SMTs). So far, however, there have been few reports of single-incision laparoscopic intragastric wedge resection. Our aim was to describe this procedure and our experience with it. METHODS: From January 2010 to December 2013, a total of 21 consecutive patients with gastric SMTs underwent single-incision intragastric resection at our institution. Their clinicopathologic data were analyzed retrospectively. RESULTS: The patients consisted of nine men and 12 women with a mean age of 51.9 +/- 12.9 years (22-69 years). Their mean body mass index was 22.6 +/- 2.0 kg/m2. Mean tumor size was 2.4 +/- 0.7 cm, with the following anatomic distribution: esophagogastric junction in three patients, fundus in twelve, upper body in three, and lower body in two. Mean operating time was 68.6 +/- 12.0 minutes. There were no conversions to open surgery and no major intraoperative complications. Time to resumption of water intake was 1.4 +/- 0.5 days. Mean hospital stay was 4.9 +/- 1.7 days. There were no recurrences or deaths during the mean 19-month follow-up. CONCLUSION: Single-incision intragastric wedge resection is a feasible and safe procedure. It is especially efficient for treating small endophytic gastric SMTs located on the upper and mid portion of the stomach.

The Comparison between Laparoscopic Wedge Resection and Open Wedge Resection for Gastric Gastrointestinal Stromal Tumors / 대한내시경복강경외과학회지

PURPOSE: A laparoscopic wedge resection is increasingly being used for gastrointestinal stromal tumors of the stomach. The aim of this study is to evaluate the safety and the feasibility of laparoscopic wedge resection compared to conventional open wedge resection. METHODS: Fifty-six patients who underwent laparoscopic wedge resection (LW group, n=32) or open wedge resection (OW group, n=24) for gastric submucosal tumor, between January 2005 and December 2007, were enrolled in this retrospective study. RESULTS: here were no significant differences in the patients' clinicopathological datas between the two groups. Although there were no significant difference in the operation time and the postoperative morbidity, the time to the first oral intake (1.2+/-1.5 vs. 1.5+/-0.6 days, p=0.015), the duration of hospital stay (3.4+/-0.7 vs. 5.5+/-0.8 days, p<0.001), and the number of analgesic use (2.2+/-0.9 vs. 4.0+/-1.2 times, p<0.001) were shorter or lower in the LW group than in the OW group. Among the LW group, three patients with endophytic growth pattern underwent intraoperative gastroduodenoscopy to identify the precise location of the tumor. CONCLUSION: Laparoscopic wedge resection is a safe and feasible treatment option for gastrointestinal stromal tumors. In addition, appropriate approach should be utilized according to the size, the location, and the growth pattern of the tumor.

Effect of melatonin on the induction of foci of aberrant crypts in the colon by azoxymethane in rats

<p><b>OBJECTIVE</b>A program of research was established on the question whether melatonin played a chemopreventive role in the development of foci of aberrant crypts in the intestinal tract of male rats. Male F344 rats were injected i.p. with an aqueous solution of 15 mg/kg azoxymethane (AOM) on day 50 and day 57, and a group was also injected i.p with 0.5 mg melatonin in 0.5 ml of 10% ethanol solution 5 times per week beginning at age 47 days. Foci and multiplicity of aberrant crypts were determined after 8 weeks. These groups of animals were kept in light daily from 4∶30 to 16∶30.</p><p><b>RESULTS</b>In the group receiving AOM and the melatonin injections, there were fewer foci of aberrant crypts in the colon and the average number of crypts was lower after 8 weeks, compared to the group on AOM alone.</p><p><b>CONCLUSIONS</b>Melatonin inhibited the formation of foci of aberrant crypts in the descending colon of rats. Also, it reduced the number of aberrant crypts per focus from foci with 3 and more aberrant crypts.</p>