Soon Chan Hong

Totally laparoscopic distal gastrectomy after learning curve completion: comparison with laparoscopy-assisted distal gastrectomy.

Purpose The aims are to: (i) display the multidimensional learning curve of totally laparoscopic distal gastrectomy, and (ii) verify the feasibility of totally laparoscopic distal gastrectomy after learning curve completion by comparing it with laparoscopy-assisted distal gastrectomy. Materials and Methods From January 2005 to June 2012, 247 patients who underwent laparoscopy-assisted distal gastrectomy (n=136) and totally laparoscopic distal gastrectomy (n=111) for early gastric cancer were enrolled. Their clinicopathological characteristics and early surgical outcomes were analyzed. Analysis of the totally laparoscopic distal gastrectomy learning curve was conducted using the moving average method and the cumulative sum method on 180 patients who underwent totally laparoscopic distal gastrectomy. Results Our study indicated that experience with 40 and 20 totally laparoscopic distal gastrectomy cases, is required in order to achieve optimum proficiency by two surgeons. There were no remarkable differences in the clinicopathological characteristics between laparoscopy-assisted distal gastrectomy and totally laparoscopic distal gastrectomy groups. The two groups were comparable in terms of open conversion, combined resection, morbidities, reoperation rate, hospital stay and time to first flatus (P>0.05). However, totally laparoscopic distal gastrectomy had a significantly shorter mean operation time than laparoscopy-assisted distal gastrectomy (P<0.01). We also found that intra-abdominal abscess and overall complication rates were significantly higher before the learning curve than after the learning curve (P<0.05). Conclusions Experience with 20~40 cases of totally laparoscopic distal gastrectomy is required to complete the learning curve. The use of totally laparoscopic distal gastrectomy after learning curve completion is a feasible and timesaving method compared to laparoscopy-assisted distal gastrectomy.

Polyphenols isolated from Allium cepa L. induces apoptosis by suppressing IAP-1 through inhibiting PI3K/Akt signaling pathways in human leukemic cells.

Allium cepa Linn is commonly used as supplementary folk remedy for cancer therapy. Evidence suggests that Allium extracts have anti-cancer properties. However, the mechanisms of the anti-cancer activity of A. cepa Linn are not fully elucidated in human cancer cells. In this study, we investigated anti-cancer effects of polyphenols extracted from lyophilized A. cepa Linn (PEAL) in human leukemia cells and their mechanisms. PEAL inhibited cancer cell growth by inducing caspase-dependent apoptosis. The apoptosis was suppressed by caspase 8 and 9 inhibitors. PEAL also up-regulated TNF-related apoptosis-inducing ligand (TRAIL) receptor DR5 and down-regulated survivin and cellular inhibitor of apoptosis 1 (cIAP-1). We confirmed these findings in other leukemic cells (THP-1, K562 cells). In addition, PEAL suppressed Akt activity and the PEAL-induced apoptosis was significantly attenuated in Akt-overexpressing U937 cells. In conclusion, our data suggested that PEAL induced caspase-dependent apoptosis in several human leukemic cells including U937 cells. The apoptosis was triggered through extrinsic pathway by up-regulating DR5 modulating as well as through intrinsic pathway by modulating IAP family members. In addition, PEAL induces caspase-dependent apoptosis at least in part through the inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. This study provides evidence that PEAL might be useful for the treatment of leukemia.

Current Status of Laparoscopic Liver Resection in Korea

Since laparoscopic liver resection was first introduced in 2001, Korean surgeons have chosen a laparoscopic procedure as one of the treatment options for benign or malignant liver disease. We distributed and analyzed a nationwide questionnaire to members of the Korean Laparoscopic Liver Surgery Study Group (KLLSG) in order to evaluate the current status of laparoscopic liver resection in Korea. Questionnaires were sent to 24 centers of KLLSG. The questionnaire consisted of operative procedure, histological diagnosis of liver lesions, indications for resection, causes of conversion to open surgery, and postoperative outcomes. A laparoscopic liver resection was performed in 416 patients from 2001 to 2008. Of 416 patients, 59.6% had malignant tumors, and 40.4% had benign diseases. A total laparoscopic approach was performed in 88.7%. Anatomical laparoscopic liver resection was more commonly performed than non-anatomical resection (59.9% vs 40.1%). The anatomical laparoscopic liver resection procedures consisted of a left lateral sectionectomy (29.3%), left hemihepatectomy (19.2%), right hemihepatectomy (6%), right posterior sectionectomy (4.3%), central bisectionectomy (0.5%), and caudate lobectomy (0.5%). Laparoscopy-related serious complications occurred in 12 (2.8%) patients. The present study findings provide data in terms of indication, type and method of liver resection, and current status of laparoscopic liver resection in Korea.

Up-regulation of RhoGDI2 in Human Breast Cancer and Its Prognostic Implications

PURPOSE Recent research has identified many genes and proteins that play specific roles in the process of systemic metastasis in various types of cancer. Rho GDP dissociation inhibitor 2 (RhoGDI2) has been shown to inhibit metastasis in human bladder cancer, but its role in breast cancer is controversial. MATERIALS AND METHODS We examined the regulation and clinical significance of RhoGDI2 in Korean breast cancer patients by using proteomic approaches. RESULTS By using a proteomic approach, we observed an increased expression of RhoGDI2 in human breast cancer tissues when compared to that of the normal breast tissues, and we validated its up-regulation in an independent cohort of 8 breast cancer patients. The clinical implication of a RhoGDI2 expression was investigated in 57 breast cancer patients by performing immunohistochemistry. RhoGDI2 did not show a significant association with the tumor size, lymph node metastasis, the histologic grade or the hormone receptor status. However, the patients with RhoGDI2-expressing tumors had significantly shorter disease-free survival (p=0.043; hazard ratio, 3.87) and distant metastasis-free survival (p=0.039; hazard ratio, 5.15). CONCLUSION Our results demonstrated a potential role of RhoGDI2 as a poor prognostic marker as well as a potential therapeutic target. The pro-metastatic nature of RhoGDI2 shown in our study may indicate its organ-specific role in cancer metastasis.

CD44 Variant 9 Serves as a Poor Prognostic Marker in Early Gastric Cancer, But Not in Advanced Gastric Cancer

Purpose The present study is to investigate the significance of CD44 variant 9 (CD44v9) expression as a biomarker in primary gastric cancer. Materials and Methods With various gastric tissues, we performed immunohistochemical staining for CD44v9. Results The positive expression rates for CD44v9 in tumor, including adenoma, early gastric cancer (EGC), and advanced gastric cancer (AGC), were higher than those in non-tumor tissues (p=0.003). In addition, the higher expression for CD44v9 was observed as the tissue becomes malignant. In the analysis of 333 gastric cancer tissues, we found that positive expression rates for CD44v9 were higher in the intestinal type or well differentiated gastric cancer than in the diffuse type or poorly differentiated gastric cancer. Interestingly, the positive expression indicated poor prognosis in EGC (5-year survival rate [5-YSR] in stage I, 81.7% vs. 95.2%; p=0.013), but not in AGC (5-YSR in stage II, 66.9% vs. 62.2%; p=0.821; 5-YSR in stage III, 34.5% vs. 32.0%; p=0.929). Moreover, strong positive expression (3+) showed a trend suggesting worse prognosis only in EGC, and it appeared to be associated with lymph node metastasis. Conclusion This study suggests that CD44v9 may be a good biomarker for prognosis prediction and for chemoprevention or biomarker-driven therapies only for EGC.

Acute gastric volvulus treated with laparoscopic reduction and percutaneous endoscopic gastrostomy

Acute gastric volvulus requires emergency surgery, and a laparoscopic approach for both acute and chronic gastric volvulus was reported recently to give good results. The case of a 50-year-old patient with acute primary gastric volvulus who was treated by laparoscopic reduction and percutaneous endoscopic gastrostomy is described here. This approach seems to be feasible and safe for not only chronic gastric volvulus, but also acute gastric volvulus.

Flavonoids from Citrus unshiu Marc. inhibit cancer cell adhesion to endothelial cells by selective inhibition of VCAM-1

Citrus fruits have been used as edible fruit and a component of traditional medicine for various diseases including cancer since ancient times. Herein, we investigated the anticancer activity of flavonoids of Citrus unshiu Marc. (FCM) focusing on anti-metastatic effects. We prepared FCM and performed experiments using MDA-MB-231 human breast cancer cells. FCM inhibited TNF-induced cancer cell adhesion to human umbilical vein endothelial cells (HUVECs) without showing any toxicity. FCM inhibited the expression of VCAM-1, but not of ICAM-1, on MDA-MB-231 cells as well as HUVECs. FCM inhibited protein kinase C (PKC) phosphorylation, but not Akt phosphorylation. FCM also inhibited cancer cell invasion in a dose-dependent manner, but not MMP-9 expression. In conclusion, this study suggested that FCM inhibits TNF-induced cancer cell adhesion to HUVECs by inhibiting VCAM-1 through inhibition of PKC, providing evidence that FCM have anti-metastatic activity by inhibiting adhesion molecules and invasion on human breast cancer cells.

Intra-abdominal angiosarcoma developing in a capsule of a foreign body: report of a case with associated hemorrhagic diathesis

BackgroundsAngiosarcoma occurs very rarely in the gastrointestinal tract and can present great diagnostic difficulty, especially when it is associated with intraabdominal abscess or granulation tissue.Case presentationWe report a case where the angiosarcoma was diagnosed after the occurrence of disseminated angiosarcoma and concurrent hemoperitoneum. The tumor developed in the fibrous capsule of a foreign body, which was possibly related to the previous appendectomy twenty years ago, and became a widely disseminated malignant neoplasm in the abdomen. After the operation, the patients course was dominated by a fatal consumptive coagulapathy. Pathologic examination of the multiple intra-abdominal lesions showed the histological and immunohistological characteristics of the angiosarcoma.ConclusionEven though angiosarcoma in the gastrointestinal tract is extremely rare, when dealing with intraabdominal abscess or the gastrointestinal bleeding in patients who have undergone surgery or radiation therapy in the past, the possibility of angiosarcoma should be considered. To make the definite diagnosis of angiosarcoma and to avoid the misdiagnosis of foreign body granuloma, thorough histological examination and immunohistochemical staining may be prerequisite.

Polyphenols Isolated from Allium cepa L. Induces Apoptosis by Induction of p53 and Suppression of Bcl-2 through Inhibiting PI3K/Akt Signaling Pathway in AGS Human Cancer Cells.

Background: The extract of Allium cepa Linn is commonly used as adjuvant food for cancer therapy. We assumed that it includes a potential source of anti-cancer properties. Methods: We investigated anti-cancer effects of polyphenols extracted from lyophilized A. cepa Linn (PEAL) in AGS human cancer cells. Results: PEAL inhibited cell growth in a dose-dependent manner. It was related to caspase-dependent apoptosis. We confirmed this finding with annexin V staining. PEAL up-regulated p53 expression, and subsequent Bax induction, down regulated Bcl-2 protein, anti-apoptotic protein. In addition, PEAL suppressed Akt activity and PEAL-induced apoptosis were significantly accentuated with Akt inhibitor (LY294002). Conclusions: Our data suggested that PEAL induce caspase-dependent apoptosis through mitochondrial pathway by up-regulating p53 protein, and subsequent Bax protein as well as by modulating Bcl-2 protein, and that PEAL induces caspase-dependent apoptosis at least in part through the inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. This study provides evidence that PEAL might be useful for the treatment of cancer.

Effectiveness of endoscopic clipping and computed tomography gastroscopy for the preoperative localization of gastric cancer

Purpose Before laparoscopic gastrectomy for gastric cancer can be planned, it is very important to know the precise location of the tumor. The aim of this study was to evaluate 3 methods of predicting the exact location of the tumor: preoperative gastrofibroscopy (GFS), preoperative computed tomography gastroscopy (CT), and intraoperative gastroscopy-guided laparoscopy (Lap). Methods In this study, 15 patients were prospectively identified, and endoscopic clips were preoperatively placed on the proximal 1 cm of the tumor, at the angle on the greater curvature and opposite the angle on the greater curvature. The distances between the pylorus and the proximal tumor clip (PT), the angle clip (PA), the greater curvature clip (PG), and the gastroesophageal junction were measured by preoperative GFS, preoperative CT, intraoperative Lap, and visual inspection (Vis). Results PT, PA, and PG values measured by preoperative GFS differed significantly from the Vis values (P < 0.01). However, preoperative CT measurements of PT, PA, and PG did not differ from the Vis values (P = 0.78, P = 0.48, and P = 0.53, respectively). Intraoperative Lap and Vis PT values differed by only 1.1 cm on an average (P = 0.10), but PA and PG values varied by 1.9 and 3.4 cm, respectively (P = 0.01 for both). Conclusion Endoscopic clipping combined with preoperative CT gastroscopy is more useful than preoperative GFS for preoperatively predicting the location of early gastric cancers and will be helpful for planning laparoscopic gastrectomy.