Ho Goon Kim

Multivisceral resection for locally advanced rectal cancer: adequate length of distal resection margin

Purpose Locally advanced rectal cancer may require an intraoperative decision regarding curative multivisceral resection (MVR) of adjacent organs. In bulky tumor cases, ensuring sufficient distal resection margin (DRM) for achievement of oncologic safety is very difficult. This study is designed to evaluate the adequate length of DRM in multiviscerally resected rectal cancer. Methods A total of 324 patients who underwent curative low anterior resection for primary pT3-4 rectal cancer between 1995 and 2004 were identified from a prospectively collected colorectal database. Results Short lengths of DRM (≤1 cm) did not compromise essentially poor oncologic outcomes in locally advanced rectal cancer (P = 0.736). However, especially in rectal cancers invading adjacent organs, DRM of less than 2 cm showed poor survival outcome. In 5-year and 10-year survival analysis of MVR, a shorter DRM (<2 cm) showed 41.9% and 30.5%, although a longer DRM (≥2 cm) showed 72.4% and 60.2% (P = 0.03, 0.044). In multivariate analysis of MVR, poorly differentiated histology, ulceroinfiltrative growth of tumor, and short DRM (<2 cm) were significant factors for prediction of poor survival outcome, although short DRM was not significantly related to local and systemic recurrence. Conclusion In locally advanced rectal cancer of pT3-4, a short length of DRM (≤1 cm) did not compromise essentially poor oncologic outcome. In rectal cancers invading adjacent organs and requiring MVR, a shorter DRM (<2 cm) was found to be related to poor survival outcome.

Is Laparoscopy-assisted Radical Gastrectomy Safe in Patients with Child-Pugh Class A Cirrhosis?

Purpose We investigated early postoperative morbidity and mortality in patients with liver cirrhosis who had undergone radical gastrectomy for gastric cancer. Materials and Methods We retrospectively reviewed the medical records of 41 patients who underwent radical gastrectomy at the Chonnam National University Hwasun Hospital (Hwasun-gun, Korea) between August 2004 and June 2009. There were few patients with Child-Pugh class B or C; therefore, we restricted patient selection to those with Child-Pugh class A. Results Postoperative complications were observed in 22 (53.7%) patients. The most common complications were ascites (46.3%), postoperative hemorrhage (22.0%) and wound infection (12.2%). Intra-abdominal abscess developed in one (2.4%) patient who had undergone open gastrectomy. Massive ascites occurred in 4 (9.8%) patients. Of the patients who underwent open gastrectomy, nine (21.9%) patients required blood transfusions as a result of postoperative hemorrhage. However, most of these patients had advanced gastric cancer. In contrast, most patients who underwent laparoscopic gastrectomy had early stage gastric cancer, and when the confounding effect from the different stages between the two groups was corrected statistically, no statistically significant difference was found. There was also no significant difference between open and laparoscopic gastrectomy in the occurrence rate of other postoperative complications such as ascites, wound infection, and intra-abdominal abscess. No postoperative mortality occurred. Conclusions Laparoscopic gastrectomy is a feasible surgical procedure for patients with moderate hepatic dysfunction.

Preoperative predictors of malignant gastric submucosal tumor

Purpose The preoperative prediction of malignant potential in patients with gastric submucosal tumors (SMTs) plays an important role in decisions regarding their surgical management. Methods We evaluated the predictors of malignant gastric SMTs in 314 patients with gastric SMTs who underwent surgery in Chonnam National University Hospital. Results The malignant SMTs were significantly associated with age (odds ratio [OR], 1.067; 95% confidence interval [CI], 1.042 to 1.091; P < 0.0001), presence of central ulceration (OR, 2.690; 95% CI, 1.224 to 5.909; P = 0.014), and tumor size (OR, 1.791; 95% CI, 1.483 to 2.164; P < 0.0001). Receiver operating characteristic curve analysis showed that tumor size was a good predictor of malignant potential. The most relevant predictor of malignant gastric SMT was tumor size with cut-offs of 4.05 and 6.40 cm. Conclusion Our findings indicated that age, central ulceration, and tumor size were significant preoperative predictors of malignant SMTs. We suggest that 4 cm be selected as a threshold value for malignant gastric SMTs. In patients with a gastric SMT larger than 4 cm with ulceration, wide resection of the full thickness of the gastric wall or gastrectomy with adequate margins should be performed because of its malignant potential.

Adverse prognostic impact of splenectomy on survival in gastric carcinoma patients: Regression and propensity score matching analysis of 1074 patients

Backgrounds Patients with proximal gastric carcinoma undergo total gastrectomy with concomitant splenectomy to ensure the complete removal of splenic hilar lymph nodes. However, the impact of splenectomy on survival remains uncertain. This study aimed to investigate the impact of splenectomy on survival among patients with gastric carcinoma. Methods Of 1074 patients who underwent total gastrectomy for proximal gastric carcinoma between 2006 and 2014, 229 patients underwent concomitant splenectomy or pancreaticosplenectomy during surgery. We investigated the prognostic impact of splenectomy using a regression and propensity score matched model. Results The splenectomy and non-splenectomy groups differed in many baseline characteristics, including tumor stage, and had respective crude 5-year survival rates of 55% and 81% (p <0.001). In a multivariate analysis adjusted for TNM stage and other prognostic factors, splenectomy was an independent poor prognostic factor for overall survival (hazard ratio [HR] = 1.67, 95% confidence interval [CI] = 1.11–2.51) and disease-free survival (HR = 1.61, 95% CI = 1.24–2.10). A survival evaluation stratified by TNM stage showed that splenectomy adversely affected survival among patients with stage III, but not stage I, II, and IV disease. In the propensity score-matched sample, splenectomy group also showed significantly worse overall survival (5-year, 65% vs. 79%, p = 0.010) and disease-free survival (5-year, 55% vs. 72%, p = 0.025) and was an independent poor prognostic factor in a multivariate analysis adjusting TNM stage and other prognostic factors. Conclusions Splenectomy adversely affects survival, particularly among patients with stage III gastric carcinoma, and should be avoided unless there is direct invasion to the splenic hilum.

Quantitative analysis of COX-2 promoter methylation in gastric carcinoma

Purpose To determine the occurrence of COX-2 methylation in gastric carcinoma (GC), the status and level of CpG methylation in the promoter region of cyclooxygenase-2 (COX-2) were analyzed in early and advanced GCs, as well as in normal gastric tissues. Methods The extent of promoter methylation of the COX-2 gene was assessed quantitatively using pyrosequencing in 60 early and 60 advanced GCs samples harvested upon gastrectomy, and 40 normal gastric mucosa samples from patients with benign gastric diseases as controls. Results The methylation frequency for the COX-2 gene was significantly higher in early than in advanced GCs (40.0% vs. 20.0%, P < 0.05). A significant difference was found in COX-2 methylation between GCs and normal gastric tissues (30.0% vs. 10.0%, by PS; P < 0.05). COX-2 gene methylation was significantly associated with the depth of invasion (P = 0.003), lymph node metastasis (P = 0.009), distant metastasis (P = 0.036), and TNM staging (P = 0.007). The overall survival of patients with COX-2 methylation was significantly lower than that of patients without COX-2 methylation (P = 0.005). Conclusion These results demonstrated that COX-2 promoter methylation was significantly higher in tumor tissues, and was an early event for GC, thus, COX-2 gene methylation may be important in the initial development of gastric carcinogenesis. Thus, GCs with methylation in COX-2 may not be good candidates for treatment with COX-2 inhibitors. Furthermore, COX-2 methylation could be a significant prognostic factor predicting a favorable effect on GC patient outcome when downregulated.

Transition from Conventional to Reduced-Port Laparoscopic Gastrectomy to Treat Gastric Carcinoma: a Single Surgeon's Experience from a Small-Volume Center

Purpose This study aimed to evaluate the surgical outcomes and investigate the feasibility of reduced-port laparoscopic gastrectomy using learning curve analysis in a small-volume center. Materials and Methods We reviewed 269 patients who underwent laparoscopic distal gastrectomy (LDG) for gastric carcinoma between 2012 and 2017. Among them, 159 patients underwent reduced-port laparoscopic gastrectomy. The cumulative sum technique was used for quantitative assessment of the learning curve. Results There were no statistically significant differences in the baseline characteristics of patients who underwent conventional and reduced-port LDG, and the operative time did not significantly differ between the groups. However, the amount of intraoperative bleeding was significantly lower in the reduced-port laparoscopic gastrectomy group (56.3 vs. 48.2 mL; P<0.001). There were no significant differences between the groups in terms of the first flatus time or length of hospital stay. Neither the incidence nor the severity of the complications significantly differed between the groups. The slope of the cumulative sum curve indicates the trend of learning performance. After 33 operations, the slope gently stabilized, which was regarded as the breakpoint of the learning curve. Conclusions The surgical outcomes of reduced-port laparoscopic gastrectomy were comparable to those of conventional laparoscopic gastrectomy, suggesting that transition from conventional to reduced-port laparoscopic gastrectomy is feasible and safe, with a relatively short learning curve, in a small-volume center.

Clinicopathological features of female gastric carcinoma patients with curative resection: comparison with male patients.

Little is known about the clinicopathological features of female gastric carcinoma (FGC) patients. We compared the clinicopathologic features and outcomes of FGC patients with curative resection with those of male gastric carcinoma (MGC) patients. We reviewed the hospital records of 940 FGC patients between 1986 and 2005 at Chonnam National University Hospital. Multivariate analysis showed that presence of serosal invasion, lymph node metastasis, and operative type were significant prognostic factors for survival of FGC patients with curative resection. Furthermore, the overall 5-year survival rate of FGC patients with curative resection (53.4%) was higher than that of MGC patients (47.6%, p<0.05). In advanced cases, no significant difference was observed in the overall 5-year survival rate between the FGC and MGC patients (41.6% vs 37.4%, p>0.05). Therefore, serosal invasion, lymph node metastasis, and type of operation were statistically significant parameters associated with survival. Early detection is more important for improving the prognosis of female patients with gastric cancer than for male patients.