Long-term oncologic outcome of D3 lymph node dissection for clinical stage 2/3 right-sided colon cancer.

PURPOSE: To investigate oncologic outcomes including overall survival and disease-free survival depending on the extent of lymphadenectomy (D3 versus D2) by comparing D3 and D2 lymphadenectomy in patients with clinical stage 2/3 right colon cancer. METHODS: Consecutive series of patients who underwent radical resection for right colon cancer at our three hospitals between January 2015 and June 2018 were retrospectively analyzed. Study cohorts were divided into two groups: D3 group and D2 group. Oncologic, pathologic, and perioperative outcomes of the two groups were compared. RESULTS: A total of 295 patients (167 in the D2 group and 128 in the D3 group) were included in this study. Patients' characteristics showed no significant difference between the two groups. The median number of harvested lymph nodes was significantly higher in the D3 group than in the D2 group. The rate of complications was not significantly different between the two groups except for chyle leakage, which was more frequent in the D3 group. Five-year disease-free survival was 90.2% (95% CI: 84.8-95.9%) in the D3 group, which was significantly (p = 0.028) higher than that (80.5%, 95% CI: 74-87.5%) in the D2 group. There was no significant difference in overall survival between the two groups. CONCLUSION: Our results indicate that D3 lymphadenectomy is associated with more favorable 5-year disease-free survival than D2 lymphadenectomy for patients with stage 2/3 right-sided colon cancer. D3 lymphadenectomy might improve oncologic outcomes in consideration of the recurrence rate.

Endoscopic Stenting for Malignant Left-Sided Large-Bowel Obstruction in Patients with Colorectal Cancer: Evaluation according to Pathological Stage.

INTRODUCTION: Self-expandable metallic stents (SEMSs) are widely used in patients with malignant left-sided large-bowel obstruction (MLLO) to convert an emergency situation into an elective one. However, the effects of endoscopic stenting on oncological outcomes remain unclear. This study aimed to analyze the oncological outcomes of SEMS placement in patients with MLLO stratified by pathological stage. METHODS: We reviewed the data of patients with MLLO that were prospectively collected between January 2005 and December 2016. Patients were divided into those who underwent SEMS placement as a bridge to surgery and those who underwent emergency surgery. Disease-free survival (DFS) and overall survival (OS) were compared between groups, and their prognostic factors were determined by pathological stage. RESULTS: SEMS placement and emergency surgery were performed in 130 and 45 patients, respectively. There was no difference in the 5-year DFS and OS rate between two groups. Subgroup analysis revealed a significant difference in the 5-year DFS and OS rate in patients with stage III MLLO, but was not observed in patients with stage II MLLO. Multivariate Cox regression analysis for stage III MLLO revealed endoscopic stenting (hazard ratio [HR], 2.051; 95% confidence interval [CI], 1.018-4.131; p = 0.044) as the only prognostic factor for DFS. Age, tumor differentiation, perineural invasion, and endoscopic stenting (HR, 3.189; 95% CI, 1.346-7.556; p = 0.008) were prognostic factors for OS. CONCLUSION: In terms of oncologic outcomes, endoscopic stenting might be more beneficial than ES in patients with stage III MLLO.

Clinical Significance of Surgical Resection Timing from Endoscopic Stenting for Left-Sided Large-Bowel Obstruction in Colorectal Cancer.

BACKGROUND: The optimal interval between self-expanding metallic stent (SEMS) insertion and surgery remains controversial in malignant left-sided large-bowel obstruction (MLLO), especially with respect to oncologic aspects. AIMS: The aim of this study is to examine whether the time interval to surgery is related to oncologic outcomes. METHODS: Prospectively collected database of MLLO between January 2005 and December 2017 were reviewed. They were divided according to established cut-off value of 14 days for the time interval to surgery. The two groups (early and late groups) were compared with respect to disease-free survival (DFS) and overall survival (OS). Additional subgroup analysis was performed using the established cut-off values for patients with stage II and III tumors. RESULTS: A total of 149 patients underwent surgery after SEMS insertion. There were no significant differences between the early and late groups in the 5-year DFS (78.0% vs 72.4%; P = 0.513) and the OS (74.2% vs 75.7%; P = 0.864) rates in all MLLO. Subgroup analysis showed that there were significant differences between the two groups for DFS and OS in stage II MLLO. The multivariate Cox regression analysis in stage II MLLO demonstrated that the time to surgery was a prognostic factor for DFS (HR, 2.051; 95% CI, 1.528-42.136; P = 0.014) and for OS (HR, 4.947; 95% CI, 1.520-16.107; P = 0.008). CONCLUSIONS: The time to surgery was demonstrated not to be a significant prognostic factor in all MLLO. However, it was a prognostic factor for patients with stage II MLLO.

Clinical Implications of Combined Lymphocyte and Neutrophil Count in Locally Advanced Rectal Cancer After Preoperative Chemoradiotherapy.

BACKGROUND: There are controversies about the ability of neutrophil to lymphocyte ratio to predict the recurrence and survival in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiation. The objective of this study is to investigate the prognostic potential of combined lymphocyte count (LC) and neutrophil count (NC) in LARC patients treated with chemoradiotherapy (CRT) followed by curative surgery. METHODS: Patients with LARC who underwent surgical resection between January 2010 and December 2017 were reviewed retrospectively. We divided the patients into three groups: high LC and low NC, low LC and high NC, and the remaining patients. The cut-off values of LC and NC were determined by receiver operating characteristic curve analysis and log-rank test statistics. We compared the disease-free survival (DFS) rate between the groups. RESULTS: A total of 176 consecutive patients were included in this study. The 5 year DFS rate was significantly different among the three groups in pathologic node (pN)+ patients (73.2% vs. 61.9% vs. 14.2%; P = 0.025). Cox multivariate analysis for pN+ patients demonstrated that combination of low LC and high NC (hazard ratio, 3.630; 95% confidence interval [CI], 1.306-10.093; P = 0.013) was significantly correlated with decreased DFS. CONCLUSIONS: This study showed that the combination of LC and NC is a powerful predictive factor for disease recurrence in pN+ LARC patients who underwent CRT.

Prognostic Reappraisal of Postoperative Carcinoembryonic Antigen in T1-2N0 Colorectal Cancer.

BACKGROUND/AIM: The purpose of this study was to compare the prognostic value of preoperative carcinoembryonic antigen (CEA), preoperative CEA/tumor size and postoperative CEA in stage I colorectal cancer. PATIENTS AND METHODS: We analyzed a total of 305 consecutive stage I colorectal cancer patients who underwent a radical surgery at our Department. The patients were divided into low and high preoperative CEA groups, low and high preoperative CEA/tumor size groups, and low and high postoperative CEA groups according to the optimal cut-off values. RESULTS: Multivariate analysis showed that postoperative CEA was independently associated with OS and DFS. However, the preoperative CEA and preoperative CEA/tumor size were not. CONCLUSION: The prognostic value of postoperative CEA is better than preoperative CEA and preoperative CEA/tumor size in patients with stage I colorectal cancer. Moreover, the common 5 ng/ml cut-off was not optimal for risk stratification in stage I colorectal cancer.