Inactivation of axon guidance molecule netrin-1 in human colorectal cancer by an epigenetic mechanism.

Netrin-1, the protein product of the NTN1 gene, is an axon guidance molecule implicated in regulation of cell survival and tumorigenesis. Expression of the netrin-1 receptors deleted in colorectal cancer (DCC) and uncoordinated 5 homolog (UNC5H) is frequently silenced in colorectal cancer (CRC) by either loss of heterozygosity or epigenetic mechanisms. However, netrin-1 expression and regulation in CRC are mostly unknown. Here, we report that NTN1 expression is significantly reduced in most CRC tissues compared to the adjacent normal intestinal mucosa, and that NTN1 DNA methylation is significantly higher in CRCs (24.6%) than in the adjacent normal intestinal mucosa (4.0%). In 6 CRC cell lines, NTN1 expression is low. Treatment with 5-Aza-2'-deoxycytidine increased expression of NTN1 in CRC cell lines, indicating that DNA methylation represses NTN1 transcription in CRCs. NTN1 DNA hypermethylation was significantly associated with advanced CRC disease. Median netrin-1 serum levels were significantly decreased in CRC patients (330.1 pg/mL) compared with normal individuals (438.6 pg/mL). Our results suggest that netrin-1 is a candidate biomarker for CRC.

Robotic-Assisted Distal Gastrectomy for Gastric Cancer Using an Oval-Shaped Port Device.

INTRODUCTION: This report describes the techniques and outcomes of robot-assisted distal gastrectomy (RDG) for gastric carcinoma using an oval-shaped port device. MATERIALS AND METHODS: A total of 15 patients underwent RDG with lymphadenectomy using the E‧Z Access/LAP-PROTECTOR oval-type device (Hakko Co., Ltd., Tokyo, Japan) performed by a single surgeon between 2018 and 2019. This device was introduced to the umbilicus under two settings, depending on the patient's figure. A horizontal setting (n=7) was used to reduce the number of trocar skin incisions in thin patients by placing a scope trocar and assist port within the E-Z Access. The vertical setting (n=8) was used for large and obese patients, enabling the endoscope position to move 50mm toward the cephalad side by rotating the device 180° to improve the surgical view of the suprapancreatic area ("dual port position" using the E‧Z Access oval-type device). The intracorporeal Billroth-I anastomosis or Roux-en-Y method was used for reconstruction. The short-term patient outcomes were determined to assess the safety and feasibility of our procedures. RESULTS: The E-Z Access oval-type device was useful for maintaining an optimal surgical field and reducing the number of skin incisions and the level of surgeon stress. Furthermore, its removal cap and wound protector allowed for an airtight seal, umbilical wound protection, and smooth specimen removal and re-pneumoperitoneum. R0 resection was accomplished in all cases without the need for conversion to open or conventional laparoscopic surgery. The median operating time was 323 (range, 245-590) minutes, and the median blood loss was 5ml. The median number of retrieved lymph nodes was 30. Neither major postoperative complication, including umbilical skin damage, nor postoperative mortality, was observed. The mean length of the hospitalization was 12.5 days. CONCLUSIONS: Our robotic approach using an oval-shaped port device for gastric cancer patients is feasible in terms of patient safety and curability.

Laparoscopic approach for port site mass diagnosed as a Schloffer tumor following surgery of ascending colon cancer.

Schloffer tumor is a foreign body granuloma that develops in the subcutaneous layer of the abdomen over several months to several years after surgery due to sutures. Here, we performed a laparoscopic resection for a benign Schloffer tumor that showed positive F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) at the port site of a laparoscopic right hemicolectomy for advanced colon cancer. We report a case in which systemic chemotherapy was avoided as a result of the histological examination following the laparoscopic approach. A 66-year-old female, who underwent laparoscopic right hemi colectomy for stage IIIA ascending colon cancer, was revealed an enhanced mass at the right side of the abdominal subcutaneous layer. PET examination showed a high accumulation of FDG. Laparoscopic tumor resection was performed. Pathological findings reported the formation identical to the Schloffer tumor. Schloffer tumor, which is rare, should be considered as one of the differential diagnoses for tumor with FDG-PET positivity at the port site during the postoperative surveillance period of colorectal cancer.

The Lymphocyte-to-monocyte Ratio Is an Independent Prognostic Indicator in Pancreatic Head Cancer that Correlates With Obstructive Jaundice.

BACKGROUND/AIM: Several indicators of systemic inflammation have been reported to predict the outcomes of patients with malignant tumors but have not been fully investigated. The aim of this study was to evaluate whether the preoperative lymphocyte-to-monocyte ratio (LMR) can predict the outcomes of patients with pancreatic head cancer. PATIENTS AND METHODS: We studied 32 patients who underwent curative surgery for pancreatic head cancer in our hospital between 2006 and 2016. Patients were classified into high and low groups according to their LMR. RESULTS: The low LMR group had a significantly lower survival rate than the high LMR group (p=0.0313). A multivariate analysis showed that the pretreatment LMR (p=0.01) was an independent risk factor for cancer-related death. The LMR was correlated with obstructive jaundice (p=0.001). CONCLUSION: Preoperative LMR is a significant predictor of the outcome after pancreaticoduodenectomy in patients with pancreatic head cancer.