Background Laparoscopic rectal surgery involving rectal transection and anastomosis with stapling devices is technically difficult. The aim of this study was to evaluate the risk factors for anastomotic leakage (AL) after laparoscopic low anterior resection (LAR) with double-stapling technique (DST) anastomosis. Methods This was a retrospective single-institution study of 154 rectal cancer patients who underwent laparoscopic LAR with DST anastomosis between June 2005 and August 2013. Patient-, tumor-, and surgery-related variables were examined by univariate and multivariate analyses. The outcome of interest was clinical AL. Results The overall AL rate was 12.3 % (19/154). In univariate analysis, tumor size (P = 0.001), operative time (P = 0.049), intraoperative bleeding (P = 0.037), lateral lymph node dissection (P = 0.009), multiple firings of the linear stapler (P = 0.041), and precompression before stapler firings (P = 0.008) were significantly associated with AL. Multivariate analysis identified tumor size (odds ratio [OR] 4.01; 95 % confidence interval [CI] 1.25–12.89; P = 0.02) and precompression before stapler firings (OR 4.58; CI 1.22–17.20; P = 0.024) as independent risk factors for AL. In particular, precompression before stapler firing tended to reduce the AL occurring in early postoperative period. Conclusions Using appropriate techniques, laparoscopic LAR with DST anastomosis can be performed safely without increasing the risk of AL. Important risk factors for AL were tumor size and precompression before stapler firings.

Chemokines and their receptors play key roles in leukocyte trafficking and are also implicated in cancer metastasis. We previously demonstrated that forced expression of CXCR3 promotes colon cancer metastasis preferentially to the draining lymph nodes (LNs), with poor prognosis. Using clinical colorectal cancer (CRC) samples, here, we show that expressions of CXCR3 and CXCR4 are significantly higher in metastatic foci within LNs and liver compared to primary tumors, whereas ligands for CXCR3 and CXCR4 are not. We also have demonstrated that some human CRC cell lines constitutively express both CXCR3 and CXCR4, and that activation of CXCR3 strengthens the CXCR4‐mediated cell migration in vitro in a synergistic manner. By constructing SW620 cell lines with reduced expression of CXCR3 and/or CXCR4 using microRNA, we investigated in vivo metastatic activities in a mouse rectal transplantation model. Six weeks after inoculation, CXCR3‐, CXCR4‐, and CXCR3/CXCR4 double‐knockdowns significantly reduced metastasis to LNs, liver and lungs, compared to the control (p < 0.05). Importantly, its suppressive effect on LN metastasis was significantly stronger in CXCR3‐ and CXCR3/CXCR4 double‐knockdowns. In addition, CXCR3‐ and CXCR3/CXCR4 double‐knockdowns significantly decreased the dissemination of cancer cells to liver and lungs, even after 2 weeks. These results indicate that targeting CXCR3 and CXCR4 can be a promising therapy against CRC metastasis.

Background: Laparoscopic surgery for rectal cancer is widely performed all over the world and several randomized controlled trials have been reported. However, the usefulness of laparoscopic surgery compared with open surgery has not been demonstrated sufficiently, especially for the low rectal area. Objective: The aim of this study was to investigate the hypothesis that laparoscopic primary tumor resection is safe and effective when compared with the open approach for locally advanced low rectal cancer. Patients and Methods: Data from patients with clinical stage II to III low rectal cancer below the peritoneal reflection were collected and analyzed. The operations were performed from 2010 to 2011. Short-term outcomes and long-term prognosis were analyzed with propensity score matching. Results: Of 1608 cases collated from 69 institutes, 1500 cases were eligible for analysis. The cases were matched into 482 laparoscopic and 482 open cases. The mean height of the tumor from the anal verge was 4.6 cm. Preoperative treatment was performed in 35% of the patients. The conversion rate from laparoscopic to open surgery was 5.2%. Estimated blood loss during laparoscopic surgery was significantly less than that during open surgery (90 vs 625 mL, P < 0.001). Overall, the occurrence of complications after laparoscopic surgeries was less than that after open surgeries (30.3% vs 39.2%, P = 0.005). Three-year overall survival rates were 89.9% [95% confidence interval (95% CI) 86.7–92.4] and 90.4% (95% CI 87.4–92.8) in the laparoscopic and open groups, respectively, and no significant difference was seen between the 2 groups. No significant difference was observed in recurrence-free survival (RFS) between the 2 groups (3-year RFS: 70.9%, 68.4 to 74.2 vs 71.8%, 67.5 to 75.7). Conclusion: Laparoscopic surgery could be considered as a treatment option for advanced, low rectal cancer below the peritoneal reflection, based on the short-term and long-term results of this large cohort study (UMIN-ID: UMIN000013919).