Hiroki Hamamoto

Oncological impact of laparoscopic lymphadenectomy with preservation of the left colic artery for advanced sigmoid and rectosigmoid colon cancer.

Background: Laparoscopic lymphadenectomy around the inferior mesenteric artery (IMA) with preservation of the left colic artery (LCA) remains a controversial approach. The aim of the study was to investigate the clinical outcomes. Methods: This study analysed 211 patients who underwent laparoscopic resection of advanced (≥T3) sigmoid and rectosigmoid colon cancers with D3 lymphadenectomy including 91 high ligations of the IMA (HL) and 120 low ligations with preservation of the LCA (LL) from January 1998 to December 2009. Results: There were no significant differences in operative result between the groups. In stage II cancer, the overall survival rate (94.8% HL vs. 91.8% LL; 95% confidence interval (CI), -0.8 to 0.68, p = 0.920) and disease-free survival (93.0% HL vs. 87.6% LL; 95% CI, -0.8 to 0.40, p = 0.540) did not differ significantly between the two groups. A similar tendency in overall survival was observed in patients with stage III cancer (88.3% HL vs. 86.9% LL; 95% CI, -0.44 to 0.57, p = 0.989) and disease-free survival (71.4% HL vs. 69.8% LL; 95% CI, -0.38 to 0.40, p = 0.637). Conclusions: Laparoscopic lymphadenectomy around the IMA with preservation of the LCA resulted in acceptable clinical outcomes in patients with advanced sigmoid and rectosigmoid colon cancer.

The utility of the subcuticular suture in hepatic resection

Aim of the study Despite recent technical progress and advances in the perioperative management of liver surgery, postoperative surgical site infection (SSI) is still one of the most common complications that extends hospital stays and increases medical expenses following hepatic surgery. Material and methods From 2001 to 2017 a total of 1180 patients who underwent hepatic resection for liver tumours were retrospectively analysed with respect to the predictive factor of superficial incisional SSI, using a propensity score matching by procedure (subcuticular or mattress suture). Results The incidence of superficial and deep incisional SSIs was found to be 7.1% (84/1180). By propensity score matching (PSM), 121 of the 577 subcuticular suture group patients could be matched with 121 of the 603 mattress suture group patients. Multivariate analysis demonstrated wound closure technique as the only independent risk factor that correlated significantly with the occurrence of superficial incisional SSIs (p = 0.038). C-reactive protein (CRP) levels on postoperative day 4 were significantly higher in patients with incisional SSIs than in those without (p < 0.001). Conclusions Wound closure technique with subcuticular continuous spiral suture using absorbable suture should be considered to minimise the incidence of incisional SSIs. Moreover, wounds should be carefully checked when CRP levels are high on postoperative day 4.

Delta-like 3 is silenced by HBx via histone acetylation in HBV-associated HCCs

Hepatocellular carcinoma (HCC) is a common malignant tumor with poor prognosis. We previously showed that expression of Delta-like 3 (DLL3), a member of the family of Delta/Serrate/Lag2 ligands for the Notch receptor, is silenced by aberrant DNA methylation and that overexpression of DLL3 in an HCC cell line induces cellular apoptosis. However, how DLL3 expression is regulated during hepatocarcinogenesis is still unclear. Here, we show that silencing of DLL3 during hepatocarcinogenesis is closely related to viral infection, especially hepatitis B virus (HBV) infection (p = 0.005). HepG2.2.15 cells, which are stably transformed with the HBV genome, showed lower DLL3 expression than the parent cell line, HepG2 cells. Treatment with Hepatitis B virus X protein (HBx) small interfering RNA upregulated DLL3 expression in HepG2.2.15 cells, and overexpression of HBx in HepG2 cells downregulated DLL3 expression. Treatment of cells with a histone deacetylase inhibitor induced DLL3 expression in HepG2.2.15 cells. These data suggest that DLL3 expression is silenced during hepatocarcinogenesis in association with HBV infection via an epigenetic mechanism.

Intestinal endometriosis combined with colorectal cancer: a case series

BackgroundIntestinal endometriosis is a common benign disease among menstruating women that affects the intestinal tract.Case presentationThis case report presents seven Japanese cases of intestinal endometriosis with colorectal cancer treated by laparoscopic surgery. Five of the seven cases reported here are women presenting with bowel obstruction due to colorectal endometriosis with colorectal cancer. It can be confused with serious lesions such as advanced colorectal cancer with peritoneal involvement or invasion of adjacent organs (T4).ConclusionsTherefore, we should consider the probability that the cause of bowel obstruction is not T4 but intestinal endometriosis. For surgical treatment, we recommend laparoscopic surgery for colorectal resection because of its benefits of differential diagnosis of T4, preserving fertility, and preventing excessive surgical stress. We performed laparoscopic resection in seven patients with intestinal endometriosis and colorectal cancer. These cases demonstrate the difficulty of establishing a differential diagnosis of intestinal endometriosis with colorectal cancer from T4.

The Relationship Between Postoperative Chemotherapy and Remnant Liver Regeneration and Outcomes After Hepatectomy for Colorectal Liver Metastasis

BackgroundPostoperative chemotherapy for treating colorectal liver metastasis (CLM) has been introduced with the aim of improving therapeutic outcomes. However, there is no consensus on the utility of multidisciplinary treatments with postoperative chemotherapy. Therefore, we evaluated surgical outcomes in patients with CLMs who underwent hepatectomy, while focusing on the effects of post-hepatectomy chemotherapy on remnant liver regeneration.MethodsTwo hundred ninety patients who underwent hepatectomy were retrospectively analyzed using propensity score matching. Postoperative outcomes were evaluated with a focus on the effects of post-hepatectomy chemotherapy on regeneration of the remnant liver in patients with CLM. The remnant liver volumes (RLVs) were measured postoperatively using multi-detector computed tomography on day 7 and months 1, 2, 5, and 12 after the operation.ResultsRLV regeneration and postoperative blood laboratory data did not differ significantly between patients who received postoperative chemotherapy and those who did not receive postoperative chemotherapy immediately after surgery or at any time point from postoperative day 7 to postoperative month 12. The recurrence rates, including same and other segmental intrahepatic recurrences, as well as the resection frequency of the remnant liver were not significantly different between the two groups.ConclusionPostoperative chemotherapy may be of small significance for patients with CLM in terms of the remnant liver volume regeneration and functional recovery.