The submucosal invasion depth predicts prognosis in early colorectal cancer. Although colorectal cancer with shallow submucosal invasion can be treated via endoscopic resection, colorectal cancer with deep submucosal invasion requires surgical colectomy. However, accurately diagnosing the depth of submucosal invasion via endoscopy is difficult. We developed a tool to diagnose the depth of submucosal invasion in early colorectal cancer using artificial intelligence. We reviewed data from 196 patients who had undergone a preoperative colonoscopy at the Osaka University Hospital and Osaka International Cancer Institute between 2011 and 2018 and were diagnosed pathologically as having shallow submucosal invasion or deep submucosal invasion colorectal cancer. A convolutional neural network for predicting invasion depth was constructed using 706 images from 91 patients between 2011 and 2015 as the training dataset. The diagnostic accuracy of the constructed convolutional neural network was evaluated using 394 images from 49 patients between 2016 and 2017 as the validation dataset. We also prospectively tested the tool from 56 patients in 2018 with suspected early-stage colorectal cancer. The sensitivity, specificity, accuracy, and area under the curve of the convolutional neural network for diagnosing deep submucosal invasion colorectal cancer were 87.2% (258/296), 35.7% (35/98), 74.4% (293/394), and 0.758, respectively. The positive predictive value was 84.4% (356/422) and the sensitivity was 75.7% (356/470) in the test set. The diagnostic accuracy of the constructed convolutional neural network seemed to be as high as that of a skilled endoscopist. Thus, endoscopic image recognition by deep learning may be able to predict the submucosal invasion depth in early-stage colorectal cancer in clinical practice.

The aim of this study was to compare the incidence of postoperative complications, including superficial incisional surgical site infection (SSI) following purse‑string skin closure (PS) and conventional skin closure with a drainage tube (CD) following stoma closure. A total of 55 consecutive patients who underwent loop colostomy and loop ileostomy closures in our hospital between October, 2011 and September, 2014 were retrospectively assessed. The patients were divided into two groups, namely the PS group (26 patients) and the CD group (29 patients). There were no significant differences in the characteristics of the patients between the two groups. The baseline and operative characteristics also did not differ significantly between the two groups. However, the incidence of superficial incisional SSI was lower in the PS group compared to that in the CD group (0 vs. 13.8%, respectively; P=0.049). The overall incidence of complications did not differ significantly between the two groups (P=0.313). The duration of postoperative hospital stay in the PS group was shorter compared to that in the CD group. In conclusion, the results of this study suggest that PS may an effective technique to reduce the incidence of superficial incisional SSI. This technique appears to be superior to the conventional technique, allowing for better cosmesis.

Background: Sarcopenia, the age-related loss of muscle mass, is a negative prognostic factor in gastrointestinal cancer. Sarcopenia combined with visceral obesity (sarcopenic obesity) is associated with poor outcomes. We explored the influence of obesity and other factors on the prognosis of patients with colorectal cancer diagnosed with sarcopenia. Methods: We enrolled 211 patients with colorectal cancer diagnosed with preoperative sarcopenic obesity who underwent radical resection at Osaka University Hospital between January 2009 and January 2012. Muscle mass was assessed using the psoas muscle mass index. Obesity was evaluated by measuring the visceral fat area in the umbilical region. Patients were categorized into two groups: sarcopenia with obesity (SO) and sarcopenia without obesity (non-SO). Overall survival, cancer-specific survival, and cancer-related relapse-free survival (CRRFS) were compared between the two groups. Patient characteristics, including age, sex, body mass index, serum albumin, C-reactive protein, tumor markers, prognostic nutritional index (PNI), modified Glasgow prognostic score (mGPS), and geriatric nutritional risk index (GNRI), were also analyzed. Results: CRRFS was significantly shorter in the SO group than in the non-SO group (p = 0.028). PNI, mGPS, and GNRI were not identified as significant prognostic factors for CRRFS. Multivariate analysis highlighted sarcopenic obesity, elevated carcinoembryonic antigen levels, and unfavorable histological types as significant predictors of poor CRRFS outcomes. Conclusions: Sarcopenic obesity is an independent predictor of poor prognosis in patients with CRC. Thus, interventions aimed at increasing muscle mass and reducing visceral fat could potentially improve the prognosis of these patients.

Previous randomized trials evaluated the effectiveness of triclosan-coated sutures for fascial closure in preventing surgical site infection (SSI). However, available evidence remains still inconclusive. We aimed to evaluate the effectiveness of triclosan-coated sutures in fascia closure in preventing postoperative SSI in elective gastrointestinal surgery. A meta-analysis included present outcomes, evaluating the advantages of triclosan-coated compared with non-coated sutures in preventing SSIs for fascia closure of laparotomy in abdominal gastrointestinal surgery. To identify prospective randomized trials regarding this topic, we searched Cochrane Central Register of Controlled Trials (Central) and PubMed with the following search terms: “triclosan or triclosan coated;” “surgical site infection;” and “randomized controlled trial” was searched, respectively. To avoid the evaluation of the heterogenous group of patients, the following studies were excluded; only emergency surgery, or not including gastroenterological surgery. The Mantel-Haenszel random-effects model was performed with R software (CRAN, R3·6·2; https://cran.r-project.org/). This meta-analysis included eleven phase-III and two prospective studies, which comprised 9588 patients. The aggregated phase-III results of the trials demonstrate a significant superiority of triclosan-coated sutures compared with non-coated sutures (random-effect model, OR 0.71, 95 % CI 0.56–0.90, P = 0.0052). The meta-analysis showed benefit with triclosan-coated sutures in preventing SSI after gastrointestinal surgery.

Circulating tumor cells (CTCs) play an important role in metastasis and recurrence. However, which cells comprise the complex tumor lineages in recurrence and are key in metastasis are unknown in colorectal cancer (CRC). CRC with high expression of POU5F1 has a poor prognosis with a high incidence of liver metastatic recurrence. We aim to reveal the key cells promoting metastasis and identify treatment-resistant lineages with established EGFP-expressing organoids in two-dimensional culture (2DOs) under the POU5F1 promotor. POU5F1-expressing cells are highly present in relapsed clinical patients’ blood as CTCs. Sorted POU5F1-expressing cells from 2DOs have cancer stem cell abilities and abundantly form liver metastases in vivo. Single-cell RNA sequencing of 2DOs identifies heterogeneous populations derived from POU5F1-expressing cells and the Wnt signaling pathway is enriched in POU5F1-expressing cells. Characteristic high expression of CTLA4 is observed in POU5F1-expressing cells and immunocytochemistry confirms the co-expression of POU5F1 and CTLA4. Demethylation in some CpG islands at the transcriptional start sites of POU5F1 and CTLA4 is observed. The Wnt/β-catenin pathway inhibitor, XAV939, prevents the adhesion and survival of POU5F1-expressing cells in vitro. Early administration of XAV939 also completely inhibits liver metastasis induced by POU5F1-positive cells.