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Clinical outcomes compared between laparoscopic and open distal pancreatectomy

BackgroundLaparoscopic surgery for pancreatic disease has gained increasing popularity. A laparoscopic distal pancreatectomy is technically simple and has been adopted as the preferred method in many centers. However, there is limited information on the outcomes of the laparoscopic surgery compared with open surgery. Therefore, this study aimed to investigate the clinical outcomes of laparoscopic distal pancreatectomy and to evaluate its efficacy compared with open distal pancreatectomy.MethodsFrom February 1995 to March 2006, 31 patients underwent laparoscopic distal pancreatectomy, and 167 patients underwent open distal pancreatectomy at Seoul National University Hospital and Bundang Seoul National University Hospital. A case–control design was used with 2:1 matching to compare laparoscopic surgery with open surgery. Among 167 patients who underwent open distal pancreatectomy, 62 patients whose age, gender, and pathology were similar to those of patients who underwent laparoscopic surgery were selected for this study. The operation time, intraoperative transfusion requirements, duration of postoperative hospitalization, complications, mortality, recurrence, and hospital charges were analyzed.ResultsThere were no significant differences in operation time, rate of intraoperative transfusions, complications, recurrence, or mortality between the two groups. Laparoscopic distal pancreatectomy was associated with a statistically significant shorter hospital stay (11.5 days vs 13.5 days; p = 0.049), but with more expensive hospital charges than open distal pancreatectomy (p < 0.01).ConclusionLaparoscopic distal pancreatectomy is a clinically safe and effective procedure for benign and borderline pancreatic tumors.

Synchronous and metachronous cancers in patients with gastric cancer

The purpose of this study is to investigate characteristics of synchronous and metachronous cancer in gastric cancer and to suggest appropriate methods of treatment management.

Long-term survival after endoscopic resection versus surgery in early gastric cancers.

BACKGROUND AND STUDY AIM Endoscopic resection for early gastric cancers that meet the expanded indication is considered to be an investigational treatment. The study aim was to evaluate long-term outcomes of endoscopic resection compared with surgery for early gastric cancers meeting the expanded indication. METHODS We retrospectively reviewed data from patients who underwent endoscopic resection or surgery for gastric cancers meeting the expanded indication between 2001 and 2009. Overall survival rate was the primary outcome; gastric cancer recurrence rates and complication rates were secondary outcomes. RESULTS Among 457 patients included, 165 underwent endoscopic resection and 292 surgery, with median follow-up duration of 58.6 months. The 5-year overall survival rates were 97.5 % and 97.0 % for endoscopic resection and surgery, respectively; Kaplan-Meier analysis showed no significant difference (P = 0.425). The 5-year gastric cancer recurrence rate was higher for endoscopic resection than for surgery (4.8 % vs. 0.3 %; P < 0.001) mainly because of metachronous cancers which developed only in the endoscopic resection group (9/165, 5.5 %). Most of the metachronous cancers (88.9 %) were curatively treated with endoscopic resection. Early complication rates were similar between the groups (P = 0.557), but the endoscopic resection group had more grade III or higher complications according to the Clavien-Dindo classification compared with the surgery group (4.8 % vs. 1.4 %, P = 0.026). Late complications occurred only following surgery (4.8 %, P = 0.004), and most (92.9 %) were grade III or higher. CONCLUSIONS Endoscopic resection may be an optimal alternative to surgery for gastric cancers that meet the expanded indication criteria, because of a comparable long-term overall survival rate.

Is the sentinel node biopsy clinically applicable for limited lymphadenectomy and modified gastric resection in gastric cancer? A meta-analysis of feasibility studies.

Sentinel node biopsies (SNBs) have been clinically applied in melanoma and breast cancer for limited lymphadenectomy. However, the use of SNB remains controversial in gastric cancer due to unsatisfactory sensitivity and variability. This meta‐analysis was performed to determine the sensitivity of SNB in gastric cancer and to identify factors that improve its sensitivity.

Predictors of Timing and Patterns of Recurrence after Curative Resection for Gastric Cancer

Aims: The aim of the study was to characterize recurrence patterns and identify predictors of recurrence after curative resection. Methods: Of 2,786 patients that underwent curative resection for gastric cancer from 2001 to 2006 at the Korean National Cancer Center, 439 (15.8%) experienced recurrence. Patterns of recurrence, clinicopathological characteristics, and therapeutic modalities were compared between 251 patients who had recurrence within 1 year (the early recurrence group) and 188 patients who had recurrence after more than a year (the late recurrence group). Multivariate analysis was performed to identify independent factors associated with the timing of recurrence. Results: In the early recurrence group, the most common pattern was hematogenous metastasis, and in the late recurrence group, the most common pattern was locoregional and peritoneal recurrence. The early recurrence group was characterized by a larger tumor, frequent lymph node (LN) metastasis, and venous, and perineural invasion. Multivariate analysis showed that LN metastasis and venous invasion were independent predictors of early recurrence. Median survival after recurrence was significantly shorter in the early recurrence group (p < 0.001). Conclusion: Hematogeneous metastasis was more common in the early recurrence group and LN metastasis and venous invasion were independent predictors of the timing of recurrence.

Emerging Role of Robot-assisted Gastrectomy: Analysis of Consecutive 200 Cases

Purpose Robotic surgery for gastric cancer is a promising alternative to laparoscopic surgery, but the data are limited. We aimed to evaluate whether gaining experience in robotic gastrectomy could improve surgical outcomes in the treatment of gastric cancer. Materials and Methods Two hundred and seven consecutive cases of patients with clinical stage I gastric cancer who underwent robotic surgery at the National Cancer Center of Korea between February 2009 and February 2012 were retrospectively reviewed. Surgical outcomes were analyzed and compared between the initial 100 and later 100 cases. Results Seven patients required conversion to open surgery and were excluded from further analysis. The mean operating time for all patients was 248.8 minutes, and mean length of hospitalization was 8.0 days. Twenty patients developed postoperative complications. Thirteen were managed conservatively, while 6 had major complications requiring invasive procedures. One mortality occurred owing to myocardial infarction. Operating time was significantly shorter in the latter 100 cases than in the initial 100 cases (269.9 versus 233.5 minutes, P<0.001). The number of retrieved lymph nodes was significantly greater in the latter cases (35.9 versus 39.9, P=0.032). The hospital stay of patients with complications was significantly longer in the initial cases than in the latter cases (16 versus 7 days, P=0.005). Conclusions Increased experience with the robotic procedure for gastric cancer was associated with improved outcomes, especially in operating time, lymph node retrieval, and shortened hospital stay of complicated patients. Further development of surgical techniques and technology might enhance the role of robotic surgery for gastric cancer.

Laparoscopy Assisted versus Open Distal Gastrectomy with D2 Lymph Node Dissection for Advanced Gastric Cancer: Design and Rationale of a Phase II Randomized Controlled Multicenter Trial (COACT 1001)

Purpose Laparoscopy-assisted distal gastrectomy for early gastric cancer has gained acceptance and popularity worldwide. However, laparoscopy-assisted distal gastrectomy for advanced gastric cancer is still controversial. Therefore, we propose this prospective randomized controlled multi-center trial in order to evaluate the safety and feasibility of laparoscopy assisted D2-gastrectomy for advanced stage gastric cancer. Materials and Methods Patients undergoing distal gastrectomy for advanced gastric cancer staged cT2/3/4 cN0/1/2/3a cM0 by endoscopy and computed tomography are eligible for enrollment after giving their informed consent. Patients will be randomized either to laparoscopy-assisted distal gastrectomy or open distal gastrectomy. Sample size calculation revealed that 102 patients are to be included per treatment arm. The primary endpoint is the non-compliance rate of D2 dissection; relevant secondary endpoints are three-year disease free survival, surgical and postoperative complications, hospital stay and unanimity rate of D2 dissection evaluated by reviewing the intraoperative video documentation. Discussion Oncologic safety is the major concern regarding laparoscopy-assisted distal gastrectomy for advanced gastric cancer. Therefore, the non-compliance rate of clearing the N2 area was chosen as the most important parameter for the technical feasibility of the laparoscopic procedure. Furthermore, surgical quality will be carefully reviewed, that is, three independent experts will review the video records and score with a check list. For a long-term result, disease free survival is considered a secondary endpoint for this trial. This study will offer promising evidence of the feasibility and safety of Laparoscopy-assisted distal gastrectomy for advanced gastric cancer.Trial Registration: NCT01088204 (international), NCCCTS-09-448 (Korea).

The lymphangiogenic factor SOX 18: A key indicator to stage gastric tumor progression

SOX group F genes are important regulators of angiogenesis and lymphangiogenesis. The aim of the present study was to examine the relationships between Sox group F expression and clinicopathological factors in gastric cancer. Three hundred and fifteen gastric cancer tissues and the corresponding normal gastric tissue were obtained from the tumor bank at the National Cancer Center, Korea. SOX group F mRNA levels in these tissues were evaluated by reverse transcriptase polymerase chain reaction (RT‐PCR). The serum levels of SOX 18 proteins in 219 gastric cancer patients and in 30 healthy volunteers were also measured by enzyme‐linked immunosorbent assay. Furthermore, immunohistochemistry (IHC) was performed on 679 gastric cancer tissues and the clinicopathological characteristics, as well as the survival rates of SOX 18 positive and negative gastric cancers were compared. RT‐PCR showed that SOX group F mRNA was increased in the gastric cancer tissues compared to the normal gastric tissues (p < 0.001, respectively). The serum levels of SOX 18 protein were also increased in gastric cancer patients compared to healthy volunteers. IHC showed that of the 679 gastric cancer cases, 177 (26.1%) were positive for SOX 18 expression in their tumor stroma, and the frequencies of both lymphovascular invasion and lymph node metastases were higher in the SOX 18 positive than in the negative group. Both the 5‐year survival and the recurrence‐free survival were shorter for SOX 18 positive tumors (p = 0.023 and 0.012, respectively). SOX 18 expression might be a prognostic tumor marker and a potential therapeutic target in gastric cancer.

Improved survival after adding dissection of the superior mesenteric vein lymph node (14v) to standard D2 gastrectomy for advanced distal gastric cancer

BACKGROUND Extended lymph node dissection in gastric cancer (D3) was proven to have no survival benefit compared with a D2 dissection, but whether adding the superior mesenteric nodes (No. 14v) to the dissection provides survival benefit for gastric cancer patients remains controversial. METHODS From April 2001 to June 2007, 1,661 patients underwent curative resection for middle or lower third gastric cancer. Patients were grouped according to No. 14v lymphadenectomy (14vD+/14vD-). Clinicopathologic characteristics and treatment-related factors were compared between the groups. Overall survival according to the clinical stage (Union for International Cancer Control tumor-node-metastasis staging 6th edition) was analyzed using the Cox proportional hazard model. RESULTS The incidence of No. 14v lymph node metastasis was 5.0%. There was no difference in morbidity or mortality between the 14vD+ and the 14vD- groups. The proportion of locoregional recurrence was greater in 14vD- group (P = .018). In clinical stages I and II, 14v lymph node dissection did not affect overall survival; in contrast, 14v lymph node dissection was an independent prognostic factor in patients with clinical stage III/IV gastric cancer (hazard ratio, 0.58; 95% confidence interval, 0.38-0.88; P = .01). CONCLUSION Extended D2 gastrectomy including No. 14v lymph node dissection seems to be associated with improved overall survival of patients with clinical stage III/IV gastric cancer in the middle or lower third of the stomach.

History of Minimally Invasive Surgery for Gastric Cancer in Korea

Laparoscopic gastrectomy was begun in 1995 in Korea. But, there was 4 years gap to reactivate in 1999. High incidence of gastric cancer and increasing proportion of early cancer through national screening program along with huge effort and enthusiasm of laparoscopic gastric surgeon, and active academic exchange with Japanese doctors contributed development of laparoscopic gastrectomy in Korea. Study group activity of Korean Laparoscopic Gastrointestinal Surgery Study (KLASS) group and Collaborative Action for Gastric Cancer (COACT) group were paramount to evoke large scale multicenter clinical study and various well performed clinical studies. This review encompasses mainly international publications about this area so far in Korea.