Sentinel Node Mapping Using a Fluorescent Dye and Visible Light During Laparoscopic Gastrectomy for Early Gastric Cancer: Result of a Prospective Study From a Single Institute.

OBJECTIVE: The aim of this study was to investigate the feasibility of sentinel node mapping using a fluorescent dye and visible light in patients with gastric cancer. BACKGROUND: Recently, fluorescent imaging technology offers improved visibility with the possibility of better sensitivity or accuracy in sentinel node mapping. METHODS: Twenty patients with early gastric cancer, for whom laparoscopic distal gastrectomy with standard lymphadenectomy had been planned, were enrolled in this study. Before lymphadenectomy, the patients received a gastrofiberoscopic peritumoral injection of fluorescein solution. The sentinel basin was investigated via laparoscopic fluorescent imaging under blue light (wavelength of 440-490 nm) emitted from an LED curing light. The detection rate and lymph node status were analyzed in the enrolled patients. In addition, short-term clinical outcomes were also investigated. RESULTS: No hypersensitivity to the dye was identified in any enrolled patients. Sentinel nodes were detected in 19 of 20 enrolled patients (95.0%), and metastatic lymph nodes were found in 2 patients. The latter lymph nodes belonged to the sentinel basin of each patient. Meanwhile, 1 patient (5.0%) experienced a postoperative complication that was unrelated to sentinel node mapping. No mortality was recorded among enrolled cases. CONCLUSIONS: Sentinel node mapping with visible light fluorescence was a feasible method for visualizing sentinel nodes in patients with early gastric cancer. In addition, this method is advantageous in terms of visualizing the concrete relationship between the sentinel nodes and surrounding structures.

Endoscopic versus surgical resection of GI stromal tumors in the upper GI tract.

BACKGROUND AND AIMS: Endoscopic resection has been performed for treatment of GI stromal tumors (GISTs) in the upper GI tract. However, the therapeutic roles of the endoscopic procedure remain debatable. We aimed in this retrospective study to evaluate the feasibility and long-term follow-up results of endoscopic resection of GISTs in the upper GI tract, compared with surgery. METHODS: Between March 2005 and August 2014, 130 cases of GIST in the upper GI tract were resected. We compared baseline characteristics and clinical outcomes including R0 resection rate and recurrence rate between the endoscopy group (n = 90) and surgery group (n = 40). RESULTS: The most common location of GIST was the stomach body in the endoscopy group, whereas it was the duodenum in the surgery group (P = .001). Tumor size was significantly smaller (2.3 vs 5.1 cm; P < .001), and procedure time (51.8 ± 36.2 vs 124.6 ± 74.7 minutes; P < .001) and hospital stay (3.3 ± 2.4 vs 8.3 ± 5.4 days; P < .001) were significantly shorter in the endoscopy group than in the surgery group. The R0 resection rate was 25.6% in the endoscopy group, whereas it was 85.0% in the surgery group (P = .001), and 50.0% of resected tumors belonged to a very low-risk group in the endoscopy group, whereas 35.0% and 30.0% belonged to low-risk and high-risk in the surgery group (P = .001). However, during 45.5 months of follow-up, the recurrence rate was not significantly different between the 2 groups (2.2% vs 5.0%; P = .586). CONCLUSIONS: Endoscopic resection might be an alternative therapeutic modality for GISTs in the upper GI tract in selective cases.

Should lymph node micrometastasis be considered in node staging for gastric cancer?: the significance of lymph node micrometastasis in gastric cancer.

BACKGROUND: In TNM staging system, lymph node staging is based on the number of metastatic lymph nodes in gastric cancer and micrometastasis is not considered. Several reports proposed the importance of lymph node micrometastasis as the causative factor for recurrence and poor survival, but it remains controversial among researchers. METHODS: A total of 482 gastric cancer patients who underwent curative resection from 2004 to 2010 at Korea University Medical Center Ansan Hospital, South Korea were prospectively enrolled. For detecting lymph node micrometastasis, immunohistochemical staining with anti-cytokeratin antibody (CAM 5.2) was performed on negative lymph nodes by hematoxylin-eosin (H-E) staining. Survival differences were compared between conventional node staging and new node staging that took micrometastasis into consideration. Also, the prognostic value of lymph node micrometastasis was investigated in multivariate analysis. RESULTS: A total of 156 patients (32.4%) showed lymph node micrometastasis. Overall, the micrometastatic group had more advanced tumor and lymph node stage, lymphovascular cancer cell invasion, a higher rate of recurrence, and poor survival. Furthermore, when the cumulative numbers of macro- and micrometastatic lymph nodes were calculated together, the discriminative power of survival difference between each node stage became more stratified. Also, multivariate analysis using Cox's proportional hazards model demonstrated perineural invasion, pathologic T stage, dissected lymph nodes, macro- and micrometastatic lymph nodes are independent prognostic factors. CONCLUSIONS: Lymph node micrometastasis was clinically significant as a risk factor for recurrent gastric cancer. Lymph node micrometastasis should be considered when estimating TNM stage for determining prognosis and the best treatment strategy.

Pattern, Timing and Survival in Patients with Recurrent Gastric Cancer.

BACKGROUND/AIMS: The aim of this study was to investigate the recurrence patterns, the timing of recurrence, and the survival rate in recurrent cases of gastric cancer. METHODOLOGY: Of 1,029 patients who underwent curative resection for gastric cancer at the Department of Surgery, Korea University Guro Hospital between 2000 and 2006, 146 patients developed recurrence and were included in this study. Timing and patterns of recurrence, the recurrence pattern according to clinicopathological factors, and post-recurrence survival rate were analyzed retrospectively. RESULTS: The mean time to recurrence was 21.2 months. Forty-two patients (28.8%) had recurrence within 1 year, and 54 patients (37.0%) had recurrence 1-2 years after surgery. Single-site recurrence occurred in 72.6% of patients, and multiple-site recurrence in 27.4%. The most frequent pattern of recurrence was peritoneal recurrence in 39.7% of patients, hematogeneous in 24.7%, locoregional in 18.5%, and to a distant lymph node in 17.1%. In cases that showed recurrence within 1 year, the most frequent pattern of recurrence was hematogeneous recurrence, while it was peritoneal in the group with recurrence between 1 and 2 years after surgery. Patterns of recurrence significantly differed according to the sex and gross tumor morphology. The mean post-recurrence survival time was 15.7 months. There was no statistically significant difference in the post-recurrence survival time according to the pattern of recurrence. CONCLUSIONS: The most frequent pattern of recurrence was peritoneal recurrence, and recurrence most often occurred within 2 years after curative resection. There was no significant difference in post-recurrence survival time according to the pattern of recurrence.

Adjuvant capecitabine and oxaliplatin for gastric cancer after D2 gastrectomy (CLASSIC): a phase 3 open-label, randomised controlled trial.

BACKGROUND: D2 gastrectomy is recommended in US and European guidelines, and is preferred in east Asia, for patients with resectable gastric cancer. Adjuvant chemotherapy improves patient outcomes after surgery, but the benefits after a D2 resection have not been extensively investigated in large-scale trials. We investigated the effect on disease-free survival of adjuvant chemotherapy with capecitabine plus oxaliplatin after D2 gastrectomy compared with D2 gastrectomy only in patients with stage II-IIIB gastric cancer. METHODS: The capecitabine and oxaliplatin adjuvant study in stomach cancer (CLASSIC) study was an open-label, parallel-group, phase 3, randomised controlled trial undertaken in 37 centres in South Korea, China, and Taiwan. Patients with stage II-IIIB gastric cancer who had had curative D2 gastrectomy were randomly assigned to receive adjuvant chemotherapy of eight 3-week cycles of oral capecitabine (1000 mg/m(2) twice daily on days 1 to 14 of each cycle) plus intravenous oxaliplatin (130 mg/m(2) on day 1 of each cycle) for 6 months or surgery only. Block randomisation was done by a central interactive computerised system, stratified by country and disease stage. Patients, and investigators giving interventions, assessing outcomes, and analysing data were not masked. The primary endpoint was 3 year disease-free survival, analysed by intention to treat. This study reports a prespecified interim efficacy analysis, after which the trial was stopped after a recommendation by the data monitoring committee. The trial is registered at ClinicalTrials.gov (NCT00411229). FINDINGS: 1035 patients were randomised (520 to receive chemotherapy and surgery, 515 surgery only). Median follow-up was 34·2 months (25·4-41·7) in the chemotherapy and surgery group and 34·3 months (25·6-41·9) in the surgery only group. 3 year disease-free survival was 74% (95% CI 69-79) in the chemotherapy and surgery group and 59% (53-64) in the surgery only group (hazard ratio 0·56, 95% CI 0·44-0·72; p<0·0001). Grade 3 or 4 adverse events were reported in 279 of 496 patients (56%) in the chemotherapy and surgery group and in 30 of 478 patients (6%) in the surgery only group. The most common adverse events in the intervention group were nausea (n=326), neutropenia (n=300), and decreased appetite (n=294). INTERPRETATION: Adjuvant capecitabine plus oxaliplatin treatment after curative D2 gastrectomy should be considered as a treatment option for patients with operable gastric cancer. FUNDING: F Hoffmann-La Roche and Sanofi-Aventis.

Robot versus laparoscopic gastrectomy for cancer by an experienced surgeon: comparisons of surgery, complications, and surgical stress.

BACKGROUND: No previous robotic studies present an equivalent surgical quality comparison in an experienced setting for gastric cancer. In addition, a reliable postoperative complication assessment is needed to accurately evaluate surgical outcomes. METHODS: After 20 cases of robotic-assisted gastrectomy (RAG), a total of 121 consecutive gastric cancer patients underwent gastrectomy (38 RAG vs 83 laparoscopic-assisted gastrectomy [LAG]) from February 2009 to November 2010 at the Department of Surgery, Korea University Anam Hospital, Seoul, Korea. The Clavien-Dindo (C-D) classification was used to classify surgical complications. The granulocyte-to-lymphocyte (G:L) ratio was analyzed to evaluate surgical stress. RESULTS: The baseline characteristics, with the exception of age, were similar. The mean total operation time for RAG (234.4 ± 48.0 min) was not significantly different than that for LAG (220.0 ± 60.6 min; P = 0.198). However, in obese patients, fewer lymph nodes were harvested by RAG (23.4 ± 7.0) than by LAG (32.2 ± 12.5, P = 0.006). Overall C-D complications were more common for RAG (47.3 vs 38.5 %), but the difference was not significant (P = 0.361). The mean hospital stay was similar for the 2 groups. Surgical stress as estimated by the G:L ratio was comparable between the 2 groups. CONCLUSIONS: RAG performed by an experienced surgeon resulted in similar postoperative outcomes and complications to those of LAG. Assessment of operation time, C-D complication grade, and G:L ratio revealed that RAG is a practical and feasible alternative to LAG, with the possible exception of obese patients.

Expression of moesin and CD44 is associated with poor prognosis in gastric adenocarcinoma.

AIMS: CD44 has been reported as a negative prognostic marker in gastric cancer. It interacts with moesin in epithelial-mesenchymal transition. To date, to our knowledge, there has been no clinical study dealing with the relationship between moesin and gastric adenocarcinoma. We analysed the expression of moesin and CD44 in gastric adenocarcinoma tissue, and correlations with clinicopathological factors. METHODS AND RESULTS: A retrospective analysis was made of 430 patients who had undergone gastrectomy at the Korea University Guro Hospital between 2002 and 2005 for gastric adenocarcinoma. Using tissue microarray and immunohistochemical staining, moesin expression was observed in 192 (44.7%) cases; it was associated significantly with poorly differentiated histology, invasion depth, lymph node metastasis, lymphatic invasion and advanced pathological TNM stage. CD44 expression was not correlated with clinicopathological features or moesin expression. Moesin expression was a strong predictor of lymph node metastasis in logistic regression analysis. Both moesin expression and CD44 expression were associated significantly with poor overall survival in univariate analysis. Furthermore, in multivariate analysis, moesin and CD44 were independent markers of poor prognosis, along with pathological TNM stage and older patient age. CONCLUSION: Moesin expression and CD44 expression might be useful markers of poor prognosis in gastric adenocarcinoma.

Expression of estrogen receptors in gastric cancer and their clinical significance.

BACKGROUNDS AND OBJECTIVES: The male predominance of gastric cancer suggests that female sex hormones may have a protective effect against gastric cancer. We evaluated the expression of estrogen receptors in gastric cancer tissue and cells and the clinical significance of ER-ß expression in gastric cancer. METHOD: ER-α, ER-ß proteins extracted from normal stomach, gastric cancer tissues, and cultured gastric cancer cells (KATO-III, mkn28, mkn45, and mkn74) were assessed by Western blot analysis. The clinical significance of ER-ß was explored using tissue microarray methods and immunohistochemical staining of specimens from 148 gastric cancers. RESULTS: Both ER-α and ß protein expression were noted in normal and gastric cancer tissues. However, in cultured gastric cells, only ER-ß was noted in mkn28 and mkn74. Of 148 gastric cancers, 67 (45.3%) were ER-ß positive. The ER-ß positive group was associated with lower tumor stage, Lauren's intestinal type, negative perineural invasion, and free of recurrence. The ER-ß positive group had a better 3-year survival compared with the negative group in survival analysis. CONCLUSION: Our results suggest that the presence of ER-ß in gastric cancer could have a protective effect against invasiveness of gastric cancer. Further studies are needed to clarify the role of ER-ß in gastric cancers.

Metastatic lymph node targeted chemosensitivity test for gastric cancer.

BACKGROUND: The objective of this study was to compare the chemosensitivity of primary tumor and metastasized lymph node from patient with gastric adenocarcinoma. MATERIALS AND METHODS: We studied 26 gastric cancer patients with lymph node metastasis who underwent gastric resection at the Korea University Guro Hospital from Feb 2007 to July 2008. The chemosensitivity of primary tumor and metastatic lymph node were studied using an adenosine triphosphate-based chemotherapy response assay (ATP-CRA). RESULTS: The concordance rate of the ATP-CRA test was 30.8% (8/26). The concordance rate between primary tumor and metastatic N2 group lymph node was only 9.1% (1/11). The metastatic tumor inhibition rates with 5-fluorouracil, cisplatin, doxorubicin, and oxaliplatin were higher than the inhibition rates for primary tumor. Tumor inhibition rates was significantly different between primary tumor and metastatic tumor after doxorubicin treatment (27.734±20.95 versus 38.403±26.87, P=0.021). We detected simple correlations of tumor inhibition rates between primary and metastatic tumors with cisplatin (r=0.661, P<0.001) and doxorubicin (r=0.475, P=0.031). CONCLUSIONS: We observed differences between first choice chemotherapeutic agents based on ATPCRA tests of primary tumor and metastatic tumor in lymph node. Therefore, chemotherapeutic agents should be carefully selected for adjuvant chemotherapy using a chemosensitivity test.

Laparoscopic resection of small gastric submucosal tumors.

BACKGROUND: No consensus exists regarding the necessity of operative resection for patients with small, asymptomatic gastric submucosal tumors (SMTs). The purpose of this study is to evaluate clinical outcomes of resection by minimally invasive surgery. METHODS: The medical records of 20 consecutive patients who had undergone laparoscopic or robotic wedge resection for small (<5 cm) gastric SMTs between March 2008 and February 2009 were reviewed. Operative indications included all SMTs unquestionably visible by endoscopy, irrespective of symptoms. The operative procedures, clinicopathologic features, and operative results were assessed. RESULTS: Out of a total of 20 patients, 17 were asymptomatic, and 3 presented with vague abdominal discomfort. One patient had two tumors, therefore 21 total lesions were resected and evaluated (19 by laparoscopy and 2 by robotic procedures). There were 12 exogastric and 9 transgastric wedge resections. Mean operative time was 84 ± 28 min, and mean length of hospitalization was 4.7 ± 1.6 days. There were no major peri- or postoperative complications or mortalities. Mean tumor size was 2.4 ± 1.2 cm (range 0.6-4.8 cm). All lesions had microscopically negative resection margins. There were 16 gastrointestinal tumors (GISTs) and 5 other benign lesions. Fifteen of the GISTs had mitotic count (MC) <5 per 50 high-power fields (HPFs), and one lesion measuring 2.5 cm in size had MC of 38 per 50 HPFs. CONCLUSIONS: Small size cannot guarantee a specific malignant risk for gastric SMTs. Laparoscopic/robotic wedge resection is safe and effective in treating small, asymptomatic lesions. Therefore, an active surgical approach should be considered for management of patients with small gastric SMTs.

Clinical significance of immunohistochemically-identified lymphatic and/or blood vessel tumor invasion in gastric cancer.

BACKGROUND: Tumor invasion and lymph node metastasis are significant prognostic factors for gastric cancer, and lymphatic and vascular tumor invasion are also significant risk factors for gastric cancer recurrence. Recently, the immunohistochemical detection of lymphatic and blood vessel tumor invasion (LBVI) has been shown to have a higher sensitivity and specificity than hematoxylin-eosin staining methods. MATERIALS AND METHODS: One hundred forty-nine gastric cancer patients who underwent curative resection at Korea University Hospital between November 2003 and December 2006 served as the study subjects. Lymphatic vessel invasion was evaluated by immunostaining with the new selective marker, D2-40, and blood vessel invasion was assessed with anti-CD31 antibody. Patients were divided according to the presence of LBVI, clinicopathologic factors were compared, and postoperative surgical outcomes were analyzed. RESULTS: LBVI was present in 66 patients (44.3%). LBVI was significantly correlated with depth of tumor invasion (P < 0.001), lymph node stage (P < 0.001), and lymph node micrometastasis (P = 0.013). Cancer recurrence was more common in the LBVI group (P = 0.007), and peritoneal seeding was the most prevalent type of recurrence (P = 0.028). Univariate analysis showed tumor size, depth of tumor invasion, lymph node stage, and LBVI to have a significant impact on survival. Based on multivariate analysis, however, depth of tumor invasion and lymph node stage were correlated with survival. CONCLUSION: Immunohistochemical demonstration of LBVI is an additional prognostic marker, and provides useful information for planning treatment strategies in gastric cancer patients.

Advanced gastric cancer in the middle one-third of the stomach: Should surgeons perform total gastrectomy?

BACKGROUND AND OBJECTIVES: To determine which optimal surgical procedure for middle-third advanced gastric cancer (AGC) based on comparative study of the long-term prognosis between total gastrectomy (TG) and distal gastrectomy (DG). METHODS: Between March 1993 and December 2005, 402 patients with middle-third AGC who underwent gastric resection were enrolled in this study. We analyzed the long-term prognosis according to the length of the proximal resection margin (PRM) and the extent of gastric resection, and determined independent prognostic factors. RESULTS: TG was performed in 244 patients (60.7%) and DG was performed in 158 patients (39.3%). There were no significant differences in the 5-year survival rates according to the length of PRM. The 5-year survival rates of patients who underwent DG were significantly higher than the rates of the patients who underwent TG in curative cases (67.8% vs. 58.4%, P = 0.037). Nevertheless, there was no significant difference in the stage-stratified survival rates according to the extent of gastric resection. Multivariate analysis revealed that surgical curability, extent of lymphadenectomy, and stage were independent prognostic factors. CONCLUSION: If curative resection can be performed, the long-term prognosis of patients with middle-third AGC was not affected by the length of PRM or the extent of gastric resection.

Clinical significance of gastric outlet obstruction on the oncologic and surgical outcomes of radical surgery for carcinoma of the distal stomach.

BACKGROUND AND OBJECTIVES: To determine the significance of gastric outlet obstruction (GOO) on the outcomes of radical surgery for distal gastric cancer. METHODS: Three hundred seventy-one patients who underwent radical surgery for advanced gastric cancer arising at the distal stomach were categorized into two groups according to the presence of GOO, that is, 59 patients with GOO and 312 patients without. Clinicopathologic variables, postoperative morbidity and mortality, recurrence pattern, and survival outcomes of the two groups were compared. RESULTS: Distal gastric carcinoma with GOO was usually diagnosed at a more advanced stage with aggressive pathologic features. GOO adversely affected overall survival after radical surgery with an odds ratio of 2.068 (P < 0.001). In patients with recurrent diseases, patients with GOO had higher rate of locoregional recurrence after radical surgery (P = 0.021). High-grade postoperative complications occurred at similar rates in both groups (P = 0.539). CONCLUSIONS: The presence of GOO is an independent prognostic factor after radical surgery for advanced distal gastric cancer and provide additional information for identifying patients at higher risk of recurrence and pattern of recurrence during follow-up. Radical surgery in patients with GOO can be performed with acceptable morbidity and mortality.

Comparison of Short-Term Outcomes Using Three-Dimensional and Two-Dimensional Laparoscopic Gastrectomy for Gastric Cancer.

Introduction: This study investigated the oncological and technical advantages of three-dimensional (3D) versus two-dimensional (2D) laparoscopic gastric cancer surgery. Materials and Methods: This study included 68 gastric cancer patients who had undergone laparoscopic distal gastrectomy at Korea University Ansan Hospital (3D group, n = 34; 2D group, n = 34). The surgical outcomes and duration of each phase were compared between the groups. Results: The total operative time with 3D laparoscopy was significantly shorter than with 2D laparoscopy (227.8 ± 39.0 versus 249.6 ± 45.3 minutes; P = .037). There were no significant differences between the groups in the number of gauze pads used, time to first postoperative flatus, and number of harvested lymph nodes (2.0 [1.0-2.0] versus 2.0 [1.0-2.0]; P = .692; 4.0 [4.0-4.0] versus 4.0 [4.0-4.0] days; P = .196; 40.8 ± 16.6 versus 44.0 ± 15.7; P = .412, respectively). The time from omentectomy to right gastric artery ligation and the duration of the reconstruction phase were shorter with 3D than with 2D laparoscopy (62.6 ± 14.5 versus 71.9 ± 18.8 minutes; P = .027; 32.3 ± 7.6 versus 47.7 ± 16.8 minutes; P < .001). Conclusion: In a procedure requiring spatial perception, the operative time was shortened by introducing 3D laparoscopy. Despite the anticipation of a better view for lymph node dissection, the 3D image showed no advantage. Further study may be required by novice surgeons.

Characteristics of proximal early gastric cancer differentiating distal early gastric cancer.

Previous studies reported substantial differences between proximal and distal gastric cancer, however, most of the cases included in these studies were advanced gastric cancers (AGCs). The aim of this study was to investigate the unique characteristics of proximal early gastric cancer (EGC) by comparing with distal EGC. From March 2007 to March 2016, proximal and distal EGC patients who underwent endoscopic or surgical resection at our institution were matched 1:3 according to age and sex. We retrospectively analyzed the clinical and histopathological information. A total of 368 patients were enrolled including 92 (25%) in the proximal and 276 (75%) in the distal group. The proportion of patients who underwent surgery (56.5 vs. 20.3%, p<0.001), undifferentiated type (38.0 vs. 19.6%, p<0.001), tumor size (29.5 ±19.4 vs. 20.3 ±16.8 mm, p<0.001) and submucosal (SM) invasion (60.9 vs. 25.7%, p<0.001) were significantly higher in the proximal group than in the distal group. In multivariate analysis, the proximal location of EGC was a significant risk factor for SM invasion in the total population (odds ratio [OR], 3.541; 95% confidence interval [CI], 2.053-6.110; p<0.001), and in subgroup with EGC < 30mm (n = 279) (OR, 5.940; 95% CI, 2.974-11.862; p<0.001). In conclusion, careful therapeutic decision of proximal EGC is essential due to the different histopathological characteristics such as large tumor size and higher potential for SM invasion.

Gastric cancer histology: clinicopathologic characteristics and prognostic value.

BACKGROUND AND OBJECTIVES: Gastric cancer can be divided into two major histologic categories, that is, differentiated and undifferentiated types. In the present study, we sought to clarify the prognoses and clinicopathologic characteristics of signet ring cell carcinoma and mucinous carcinoma, both of which are mucin-producing tumors of the undifferentiated type. METHODS: We retrospectively reviewed medical records of 2,275 patients who underwent gastric resection. Cases were divided into four histologic groups: differentiated carcinoma (well differentiated and moderately differentiated, WMD), poorly differentiated (PD), signet ring cell carcinoma (SRC), and mucinous carcinoma (MC). RESULTS: The overall cumulative 5-year survival rates for patients were 67% for WMD, 54% for PD, 65% for SRC, and 48% for MC. The outcome of SRC was similar to that of WMD, whereas that of MC was similar to that of PD. Stage-stratified analysis revealed that histologic type was not statistically related to survival in patients with stage I, II, or III. On the other hand, histologic type in patients with stage IV disease was found to be significantly associated with survival. CONCLUSIONS: Histologic classifications of mucin-producing gastric cancers should separately be considered from other histologic types.

Laparoscopic treatment of a huge cystic lymphangioma: partial aspiration technique with a spinal needle.

A cystic lymphangioma is a rare intra-abdominal lesion. Treatment is a complete excision of the cyst because of complications and a rare chance of malignancy. In this paper we report on 2 patients with a huge cystic lymphangioma who were treated by laparoscopic surgery successfully. Each of the cysts were 13 and 11 cm in diameter, were diagnosed by ultrasonography and computed tomography scan. After partial aspiration of the cysts, using a spinal needle, we were prone to grasp the cysts without spillage. Traction and dissection were easy without spillage or injury of the mesenteric vessels. The laparoscopic approach can be successfully and safely performed by an experienced surgeon in keeping with oncologic principles.

Comparison of oncological benefits of deep neuromuscular block in obese patients with gastric cancer (DEBLOQS_GC study): A study protocol for a double-blind, randomized controlled trial.

PURPOSE: Many studies have demonstrated the advantage of maintaining intraoperative deep neuromuscular block (NMB) with sugammadex. This trial is designed to evaluate the impact of muscle relaxation during laparoscopic subtotal gastrectomy on the oncological benefits, particularly in obese patients with gastric cancer. MATERIALS AND METHODS: This is a double-blind, randomized controlled multicenter prospective trial. Patients with clinical stage I-II gastric cancer with a body mass index of 25 and over, who undergo laparoscopic subtotal gastrectomy will be eligible for trial inclusion. The patients will be randomized into a deep NMB group or a moderate NMB group with a 1:1 ratio. A total of 196 patients (98 per group) are required. The primary endpoint is the number of harvested lymph nodes, which is a critical index of the quality of surgery in gastric cancer treatment. The secondary endpoints are surgeon's surgical condition score, patient's sedation score, and surgical outcomes including peak inspiratory pressure, operation time, postoperative pain, and morbidity. DISCUSSION: This is the first study that compares deep NMB with moderate NMB during laparoscopic gastrectomy in obese patients with gastric cancer. We hope to show the oncologic benefits of deep NMB compared with moderate NMB during subtotal gastrectomy. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (NCT03196791), date of registration: October 10, 2017.

Clinical and genomic landscape of gastric cancer with a mesenchymal phenotype.

Gastric cancer is a heterogeneous cancer, making treatment responses difficult to predict. Here we show that we identify two distinct molecular subtypes, mesenchymal phenotype (MP) and epithelial phenotype (EP), by analyzing genomic and proteomic data. Molecularly, MP subtype tumors show high genomic integrity characterized by low mutation rates and microsatellite stability, whereas EP subtype tumors show low genomic integrity. Clinically, the MP subtype is associated with markedly poor survival and resistance to standard chemotherapy, whereas the EP subtype is associated with better survival rates and sensitivity to chemotherapy. Integrative analysis shows that signaling pathways driving epithelial-to-mesenchymal transition and insulin-like growth factor 1 (IGF1)/IGF1 receptor (IGF1R) pathway are highly activated in MP subtype tumors. Importantly, MP subtype cancer cells are more sensitive to inhibition of IGF1/IGF1R pathway than EP subtype. Detailed characterization of these two subtypes could identify novel therapeutic targets and useful biomarkers for prognosis and therapy response.

Multiple malignant extragastrointestinal stromal tumors of the greater omentum and results of immunohistochemistry and mutation analysis: a case report.

To report an extragastrointestinal stromal tumor (EGIST) that occurs outside the gastrointestinal tract and shows unique clinicopathologic and immunohistochemical features. In our case, we experienced multiple soft tissue tumors that originate primarily in the greater omentum, and in immunohistochemical analysis, the tumors showed features that correspond to malignant EGIST. Two large omental masses measured 15 cm multiply 10 cm and 5 cm multiply 4 cm sized and several small ovoid fragments were attached to small intestine, mesentery and peritoneum. On histologic findings, the masses were separated from small bowel serosa and had high mitotic count (115/50 HPFs). In the results of immunohistochemical stains, the tumor showed CD117 (c-kit) positive reactivity and high Ki-67 labeling index. On mutation analysis, the c-kit gene mutation was found in the juxtamembrane domain (exon 11) and it was heterozygote. Platelet-derived growth factor receptor (PDGFR) gene mutation was also found in the juxtamemembrane (exon 12) and it was polymorphism. From above findings, we proposed that there may be several mutational pathways to malignant EGIST, so further investigations could be needed to approach this unfavorable disease entity.