Gyu Seok Cho

Soonchunhyang University, Onyang, Chungcheongnam-do, South Korea

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Publications (29)82.43 Total impact

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    ABSTRACT: A small number of nomograms have been previously developed to predict the individual survival of patients who undergo curative resection for gastric cancer. However, all were derived from single high-volume centers. The aim of this study was to develop and validate a nomogram for gastric cancer patients using a multicenter database. We reviewed the clinicopathological and survival data of 2012 patients who underwent curative resection for gastric cancer between 2001 and 2006 at eight centers. Among these centers, six institutions were randomly assigned to the development set, and the other two centers were assigned to the validation set. Multivariate analysis using the Cox proportional hazard regression model was performed, and discrimination and calibration were evaluated by external validation. Multivariate analyses revealed that age, tumor size, lymphovascular invasion, depth of invasion, and metastatic lymph nodes were significant prognostic factors for overall survival. In the external validation, the concordance index was 0.831 (95% confidence interval, 0.784-0.878), and Hosmer-Lemeshow chi-square statistic was 3.92 (P = 0.917). We developed and validated a nomogram to predict 5-year overall survival after curative resection for gastric cancer based on a multicenter database. This nomogram can be broadly applied even in general hospitals and is useful for counseling patients, and scheduling follow-up.
    PLoS ONE 02/2015; 10(2):e0119671. DOI:10.1371/journal.pone.0119671 · 3.53 Impact Factor
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    ABSTRACT: The aim of this study was to investigate learning curves for surgeons performing D2 lymph node dissection based on actual patient survival. A total of 3,284 patients with gastric cancer who underwent curative intent gastric cancer surgery by nine surgeons in eight Korean hospitals between 2001 and 2006 were included. Each surgeon's experience was coded as the number of D1 + β or more gastrectomies performed before that for each patient, which indicates the surgeon's total number of prior surgical experiences. Surgeon experience was grouped into two sets of categories. The set of categories included four groups of experience: ≤50, 51-100, 101-200, and >200 applicable operations. Multivariate survival time regression models were used to evaluate the association between surgeon experience and overall survival. The learning curve for gastric cancer survival after open gastric cancer surgery was steep and did not reach a plateau until a surgeon completed 100 operations. Overall survival rate was the lowest among patients treated by a surgeon with an experience of 50-100 cases. The overall survival of patients at 5 years when the surgeon had a history of more than 100 experiences was higher in each stage than that when the surgeon had a history of fewer than 100 experiences. As a surgeon's experience increases, survival after gastric cancer surgery improves. Special attention needs to be paid to the second period of surgeon experience because survival of patients in this period was the lowest.
    Gastric Cancer 02/2015; DOI:10.1007/s10120-015-0477-0 · 4.83 Impact Factor
  • 01/2015; 15(1). DOI:10.7704/kjhugr.2015.15.1.53
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    ABSTRACT: Whether signet ring cell (SRC) histology carries a worse prognosis than other forms of gastric adenocarcinoma has been questioned. The present study investigated the differences in clinicopathologic features and survival between SRC and non-SRC adenocarcinoma. The prospectively collected data of 2643 patients who had undergone curative gastrectomy between 1998 and 2005 by 10 surgeons were reviewed. Additionally, we employed analysis of covariance, propensity-score risk adjustment, and propensity-based matching to account for possible selection bias. The baseline characteristics of prematched patients with SRC or non-SRC adenocarcinoma histology differed: SRC presented in younger patients and less often in men, was more likely found in the middle stomach, and was more likely to be Stage I. After applying the propensity-score strata and propensity-score matching, there was no difference in the baseline characteristics, and SRC was not an independent risk factor for mortality in the same stage. SRC is not an independent predictor of poor prognosis after curative resection for gastric cancer in Korea.
    Medicine 12/2014; 93(27):e136. DOI:10.1097/MD.0000000000000136 · 4.87 Impact Factor
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    ABSTRACT: There are two surgical procedures for proximal early gastric cancer (EGC): total gastrectomy (TG) and proximal gastrectomy (PG). This study aimed to compare the long-term outcomes of PG with those of TG. Between January 2001 and December 2008, 170 patients were diagnosed with proximal EGC at Soonchunhyang University Cheonan Hospital, of which 64 patients underwent PG and 106 underwent TG. Clinicopathologic features, postoperative complications, blood chemistry data, changes in body weight, and oncological outcomes were analyzed and retrospectively compared between both groups. Tumor size was smaller and the number of retrieved lymph nodes was lower in the PG group. The postoperative complication rate was 10.9% in the TG group and 16.9% in the PG group. The incidence of Los Angeles grade C and D reflux esophagitis was significantly higher in the TG group. Hemoglobin level was higher and body weight loss was greater in the TG group at 2, 3, and 5 years postoperatively. The albumin levels at 3 and 5 years were lower in the TG group. There was no significant difference in the 5-year overall survival rates between the two groups (P=0.789). Postoperative complications and oncologic outcomes were observed to be similar between the two groups. The PG group showed better laboratory data and weight loss than did the TG group. Moreover, severe reflux esophagitis occurred less frequently in the PG group than in the TG group. PG can be considered as an effective surgical treatment for proximal EGC.
    12/2014; 14(4):246-51. DOI:10.5230/jgc.2014.14.4.246
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    ABSTRACT: Background/Aims This study aimed to compare the outcomes of endoscopic submucosal dissection (ESD) and gastrectomy based on the two sets of indications for ESD, namely guideline criteria (GC) and expanded criteria (EC). Methods Between January 2004 and July 2007, 213 early gastric cancer (EGC) patients were enrolled in this study. Of these patients, 142 underwent ESD, and 71 underwent gastrectomy. We evaluated the clinical outcomes of these patients according to the criteria. Results The complication rates in the ESD and gastrectomy groups were 8.5% and 28.2%, respectively. The duration of hospital stay was significantly shorter in the ESD group than the gastrectomy group according to the GC and EC (p<0.001 and p<0.001, respectively). There was no recurrence in the ESD and gastrectomy groups according to the GC, and the recurrence rates in the ESD and gastrectomy groups were 4.7% and 0.0% according to the EC, respectively (p=0.279). The occurrence rates of metachronous cancer in the ESD and gastrectomy groups were 5.7% and 5.0% according to the GC (p=1.000) and 7.5% and 0.0% according to the EC (p=0.055), respectively. Conclusions Based on safety, duration of hospital stay, and long-term outcomes, ESD may be an effective and safe first-line treatment for EGC according to the EC and GC.
    Gut and liver 09/2014; 8(5):519-25. DOI:10.5009/gnl13061 · 1.49 Impact Factor
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    ABSTRACT: Bariatric surgery is considered to be the effective treatment alternative conducted over the lifetime for reducing weight in patients with clinically morbid obesity. For many patients, the benefits of weight loss, including decreases in blood glucose, lipids, and blood pressure as well as increase in mobility, will outweigh the risks of surgical complications. But patients undergoing bariatric surgery have the least risk for long-term diet-related complications as reported in several studies. Thus, with an increasing number of severely obese patients undergoing bariatric surgery, the multidisciplinary healthcare system will need to be managed continuously. Many nutrition support specialists will need to become familiar with the metabolic consequences for the frequent monitoring of nutrition status of the patients. South Korea has a very short history with bariatric surgery, and relatively few studies have been conducted on bariatric surgery. Therefore, the objective of this report was to compare the nutrient intake, weight loss, body fat composition, and visceral fat before and after the bariatric surgery.
    07/2014; 3(2):157. DOI:10.7762/cnr.2014.3.2.157
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    ABSTRACT: The oncologic outcomes of laparoscopy-assisted gastrectomy for the treatment of gastric cancer have not been evaluated. The aim of this study is to validate the efficacy and safety of laparoscopic gastrectomy for gastric cancer in terms of long-term survival, morbidity, and mortality retrospectively. The study group comprised 2,976 patients who were treated with curative intent either by laparoscopic gastrectomy (1,477 patients) or open gastrectomy (1,499 patients) between April 1998 and December 2005. The long-term 5-year actual survival analysis in case-control and case-matched population was conducted using the Kaplan-Meier method. The morbidity and mortality and learning curves were evaluated. In the case-control study, the overall survival, disease-specific survival, and recurrence-free survival (median follow-up period, 70.8 months) were not statistically different at each cancer stage with the exception of an increased overall survival rate for patients with stage IA cancer treated via laparoscopy (laparoscopic group; 95.3%, open group: 90.3%; P < .001). After matching using a propensity scoring system, the overall survival, disease-specific survival, and recurrence-free survival rates were not statistically different at each stage. The morbidity of the case-matched group was 15.1% in the open group and 12.5% in the laparoscopic group, which also had no statistical significance (P = .184). The mortality rate was also not statistically significant (0.3% in the open group and 0.5% in the laparoscopic group; P = 1.000). The mean learning curve was 42. The long-term oncologic outcomes of laparoscopic gastrectomy for patients with gastric cancer were comparable to those of open gastrectomy in a large-scale, multicenter, retrospective clinical study.
    Journal of Clinical Oncology 01/2014; 32(7). DOI:10.1200/JCO.2013.48.8551 · 18.43 Impact Factor
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    ABSTRACT: Despite the initial absolute or relative contraindication of laparoscopic surgery during pregnancy, in the last decade, laparoscopic appendectomy (LA) has been performed in pregnant women. But few studies compare the outcomes of LA compared with open appendectomy (OA). We investigated clinical outcomes to evaluate the safety and efficacy of LA compared with OA in pregnant women. We recruited consecutive pregnant patients with a diagnosis of acute appendicitis who were undergoing LA or OA between May 2007 and August 2011 into the study. Sixty-one patients (22 LA and 39 OA) enrolled in our study. There were no significant differences in duration of surgery, postoperative complication rate and obstetric and fetal outcomes, including incidence of preterm labour, delivery type, gestation age at delivery, birth weight and APGAR scores between the 2 groups. However, the LA group had shorter time to first flatus (2.4 ± 0.4 d v. 4.0 ± 1.7 d, p = 0.034), earlier time to oral intake (2.3 ± 1.6 d v. 4.1 ± 1.9 d, p = 0.023) and shorter postoperative hospital stay (4.2 ± 2.9 d v. 6.9 ± 3.7 d, p = 0.043) than the OA group. Laparoscopic appendectomy is a clinically safe and effective procedure in all trimesters of pregnancy and should be considered as a standard treatment alternative to OA. Further evaluation including prospective randomized clinical trials comparing LA with OA are needed to confirm our results.
    Canadian journal of surgery. Journal canadien de chirurgie 10/2013; 56(5):341-6. DOI:10.1503/cjs.022112 · 1.27 Impact Factor
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    ABSTRACT: Radiation image sensor properties affect the dose of radiation that patients are exposed to in a clinical setting. Numerous radiation imaging systems use scintillators as materials that absorb radiation. Rare-earth scintillators produced from elements such as gadolinium, yttrium, lutetium, and lanthanum have been investigated to improve the properties of radiation imaging systems. Although such rare-earth scintillators are manufactured with a bulk structure, they exhibit low resolution and low efficiency when they are used as conversion devices. Nanoscintillators have been proposed and researched as a possible solution to these problems. According to the research, the optical properties and size of fine scintillators are affected by the sintering temperature used to produce nanoscintillators instead of the existing bulk-structured scintillators. Therefore, the main purpose of this research is to develop radiation-imaging sensors based on nanoscintillators in order to evaluate the quantitative properties of various scintillators produced under various conditions such as sintering temperature. This is accomplished by measuring acquired phantom images, and modulation transfer functions (MTFs) for complementary-symmetry metal-oxide-semiconductor (CMOS) image sensors under the same X-ray conditions. Low-temperature solution combustion was used to produce fine scintillators consisting of 5 wt% of europium as an activator dopant in a Gd2O3 scintillator host. Variations in the characteristics of the fine scintillators were investigated. The characteristics of fine scintillators produced at various sintering temperatures (i.e., 600, 800, or 1000 degrees C) and with a europium concentration of 0.5 wt% were also analyzed to determine the optimal conditions for synthesizing the fine scintillators.
    Journal of Nanoscience and Nanotechnology 10/2013; 13(10):7026-9. DOI:10.1166/jnn.2013.7668 · 1.34 Impact Factor
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    ABSTRACT: A randomized controlled trial to evaluate the long-term outcomes of laparoscopic distal gastrectomy for gastric cancer is currently ongoing in Korea. Patients with cT1N0M0-cT2aN0M0 (American Joint Committee on Cancer, 6th edition) distal gastric cancer were randomized to receive either laparoscopic or open distal gastrectomy. For surgical quality control, the surgeons participating in this trial had to have performed at least 50 cases each of laparoscopy-assisted distal gastrectomy and open distal gastrectomy and their institutions should have performed more than 80 cases each of both procedures each year. Fifteen surgeons from 12 institutions recruited 1,415 patients. The primary endpoint is overall survival. The secondary endpoints are disease-free survival, morbidity, mortality, quality of life, inflammatory and immune responses, and cost-effectiveness (ClinicalTrials.gov ID: NCT00452751).
    Journal of the Korean Surgical Society 02/2013; 84(2):123-30. DOI:10.4174/jkss.2013.84.2.123 · 0.62 Impact Factor
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    ABSTRACT: A 53-year-old woman was diagnosed with gastrointestinal stromal tumor (GIST) of the stomach. Computed tomography (CT) revealed a huge mass (12 cm in diameter), likely to invade pancreas and spleen. In the operation field, the tumor was in an unresectable state. The patient was then started on imatinib therapy for 4 months. On follow-up imaging studies, the tumor almost disappeared. We performed total gastrectomy and splenectomy upon which two small-sized residual tumors were found on microscopy. In this paper, we describe a case of clinicopathologic change in unresectable GIST after neoadjuvant imatinib mesylate.
    02/2012; 82(2):120-4. DOI:10.4174/jkss.2012.82.2.120
  • Gyu Seok Cho
    06/2011; 7(1):40-46. DOI:10.14216/kjco.11007
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    ABSTRACT: A 54 year old man was referred to our hospital with gastric cancer. The patient had a history of splenectomy and a left nephrectomy as a result of a traffic accident 15 years earlier. The endoscopic findings were advanced gastric cancer at the lower body of the stomach. Abdominal ultrasonography (USG) and magnetic resonance imaging demonstrated a metastatic nodule in the S2 segment of the liver. Eventually, the clinical stage was determined to be cT2cN1cM1 and a radical distal gastrectomy, lateral segmentectomy of the liver were performed. The histopathology findings confirmed the diagnosis of intrahepatic splenosis, omental splenosis. Hepatic splenosis is not rare in patients with a history of splenic trauma or splenectomy. Nevertheless, this is the first report describing a patient with gastric cancer and intrahepatic splenosis that was misinterpreted as a liver metastatic nodule. Intra-operative USG guided fine needle aspiration should be considered to avoid unnecessary liver resections in patients with a suspicious hepatic metastasis.
    03/2011; 11(1):64-8. DOI:10.5230/jgc.2011.11.1.64
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    ABSTRACT: Although a novel technique for the performance of intestinal sutureless anastomosis using a compression device has recently been investigated, it has not yet received widespread acceptance. We performed a multicenter prospective randomized trial in order to determine the clinical efficacy of the NiTi Hand CAC 30, a type of compression anastomosis clip (CAC), for jejunojejunostomy in gastric cancer surgery. Forty-seven patients from 6 institutions, who were diagnosed with gastric adenocarcinoma, were enrolled; these patients were randomized to a CAC group and a hand-sewn (control) group. Three patients dropped out for various reasons, and results for 44 patients were finally analyzed. The CAC group consisted of 20 patients, and there were 24 patients in the control group. Anastomosis time, the primary endpoint of this trial, was shorter in the CAC group than in the control group (P < 0.001). However, total operation times (P = 0.055) did not differ. All reconstructions were completed by Roux-en-Y anastomosis, and the complication rates of the two groups did not differ (P = 0.908); however, jejunojejunostomy leakage occurred in two patients in the CAC group. Our prospective multicenter clinical trial showed that the use of the NiTi Hand CAC™ 30 for jejunojejunostomy in gastric cancer surgery was feasible and could reduce anastomosis time. However, considering that there were two cases of leakage, extended use of the NiTi Hand CAC™ 30 should be carefully applied.
    Gastric Cancer 02/2011; 14(2):124-9. DOI:10.1007/s10120-011-0010-z · 4.83 Impact Factor
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    ABSTRACT: Since Kalloo and colleagues first reported the feasibility and safety of a peroral transgastric approach in the porcine model in 2004, various groups have reported more complex natural orifice transluminal endoscopic surgery (NOTES) procedures, such as the cholecystectomy, splenectomy and liver biopsy, in the porcine model. Natural orifice access to the abdominal cavity, such as transgastric, transvesical, transcolonic, and transvaginal, has been described. Although a novel, minimally invasive approach to the abdominal cavity is a peroral endoscopic transgastric approach, there are still some challenging issues, such as the risk of infection and leakage, and the method of gastric closure. Hybrid-NOTES is an ideal first step in humans. Human hybrid transvaginal access has been used for years by many surgeons for diagnostic and therapeutic purposes. Here, we report a transvaginal flexible endoscopic appendectomy, with a 5-mm umbilical port using ultrasonic scissors in a 74-year-old woman with acute appendicitis.
    Journal of the Korean Society of Coloproctology 12/2010; 26(6):429-32. DOI:10.3393/jksc.2010.26.6.429
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    ABSTRACT: Since reconstruction after laparoscopy-assisted distal gastrectomy (LADG) is performed through a small minilaparotomy window, the clinical course and complication rate are influenced by clinical technical expertise and experience. The aim of this study was to compare postoperative complications and survival rates of Billroth I and Billroth II reconstructions after LADG. We retrospectively collected data from 1,259 patients who underwent LADG performed by ten surgeons at ten hospitals between April 1998 and December 2005. Patients were classified into two groups according to reconstruction method used: the Billroth I group (n=875) and the Billroth II group (n=384). Patient and tumor characteristics, operative details, and postoperative complications were analyzed. Billroth II reconstruction was performed on obese patients (p=0.003) and patients with more advanced tumors (p<0.001). Billroth I reconstruction was performed more frequently in the lower portion of the stomach (p<0.001) and yielded shorter operating times. The postoperative complication rate was 11.4% in the Billroth I group, which was lower than that in the Billroth II group (16.9%) (p=0.011). However, the differences in the major complication rates were not statistically significant (p=0.263). Of the intra-abdominal complications, intraluminal or intraperitoneal bleeding was the most frequent complication in the Billroth I group and duodenal stump leakage was the most frequent in the Billroth II group. The postoperative mortality rate did not show a statistically significant difference. Both Billroth I and Billroth II techniques are feasible and safe reconstruction methods after LADG for gastric cancer. To reduce major complication rates, surgeons should pay attention to bleeding in Billroth I reconstruction and stump leakage in Billroth II reconstruction.
    Surgical Endoscopy 12/2010; 25(6):1953-61. DOI:10.1007/s00464-010-1493-0 · 3.31 Impact Factor
  • 06/2010; 6(1):27-32. DOI:10.14216/kjco.10004
  • G. S. Cho, W. Kim
    British Journal of Surgery 05/2010; 97(5):791 - 792. DOI:10.1002/bjs.7068 · 5.21 Impact Factor
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    ABSTRACT: The risk of recurrence and recurrence patterns after laparoscopy-assisted gastrectomy for gastric cancer remain unclear. The objective of this study is to assess recurrence and its timing, patterns, and risk factors following laparoscopy-assisted gastrectomy from multicenter data. A retrospective multicenter study was performed using data from 1,485 patients who had undergone laparoscopy-assisted gastrectomy for gastric cancer at ten institutions from 1998 to 2005. Recurrence and its timing and patterns were reviewed. Univariate and multivariate analyses were performed to identify risk factors for recurrence. Excluding 68 patients (9 postoperative mortalities, 1 synchronous distant metastasis, 2 nonadenocarcinomas, and 56 losses to follow-up), 50 of 1,417 patients (3.5%) had recurrences. Incidence of recurrence was 1.6% (19/1186) in early gastric cancer and 13.4% (31/231) in advanced gastric cancer. Recurrence occurred in 34 of 50 patients (68.0%) within 2 years of surgery, and in 45 of 50 patients (90.0%) within 3 years. The recurrence pattern was hematogenous in 17 patients (34.0%), peritoneal in 11 (22.0%), locoregional in 10 (20.0%), distant lymph nodes in 2 (4.0%), and mixed in 10 (20.0%). Advanced T-classification and lymph node metastases were risk factors for recurrence. Laparoscopy-assisted gastrectomy showed satisfactory long-term oncologic outcomes similar to those of open surgery. The study provides additional evidence suggesting that laparoscopy-assisted gastrectomy is a good alternative to open gastrectomy in patients with gastric cancer of relatively early stage, although results of a randomized controlled trial and more long-term follow-up are needed to provide conclusive evidence.
    Annals of Surgical Oncology 02/2010; 17(7):1777-86. DOI:10.1245/s10434-010-0932-4 · 3.94 Impact Factor

Publication Stats

588 Citations
82.43 Total Impact Points

Institutions

  • 2008–2015
    • Soonchunhyang University
      • College of Medicine
      Onyang, Chungcheongnam-do, South Korea
    • Bucheon College
      Bucheon, Gyeonggi Province, South Korea
    • Catholic University of Korea
      • College of Medicine
      Seoul, Seoul, South Korea
  • 2013
    • Inje University
      • Department of Biomedical Engineering
      Kŭmhae, Gyeongsangnam-do, South Korea