Comparative analysis of organ preservation attempt and radical surgery in clinical T2N0 mid to low rectal cancer.

PURPOSE: Debate persists regarding the feasibility of adopting an organ-preserving strategy as the treatment modality for clinical T2N0 rectal cancer. This study aimed to compare the outcomes of attempting organ-preserving strategies versus radical surgery in patients with clinical T2N0 mid to low rectal cancer. METHODS: Patients diagnosed with clinical T2N0 rectal cancer, with lesions located within 8 cm from the anal verge as determined by pre-treatment magnetic resonance imaging between January 2010 and December 2020 were included. RESULTS: Of 119 patients, 91 and 28 were categorized into the organ-preserving attempt group and the radical surgery group, respectively. The median follow-up duration was 48.8 months (range, 0-134 months). The organ-preserving attempt group exhibited a reduced incidence of stoma formation (44.0% vs. 75.0%; p = 0.004) and a lower occurrence of grade 3 or higher surgical complications (5.8% vs. 21.4%; p = 0.025). Univariate analyses revealed no significant association between treatment strategy and 3-year local recurrence-free survival (organ-preserving attempt 87.9% vs. radical surgery 96.2%; p = 0.129), or 3-year disease-free survival (79.6% vs. 84.9%; p = 0.429). Multivariate analysis did not identify any independent prognostic factors associated with oncologic outcomes. CONCLUSION: Compared with radical surgery, attempted organ preservation resulted in lower incidences of stoma formation and severe surgical complications, whereas oncological outcomes were comparable. Attempting organ preservation may be a safe alternative to radical surgery for clinical T2N0 mid to low rectal cancer.

Characteristics and risk factors of axillary lymph node metastasis of microinvasive breast cancer.

PURPOSE: To select patients who would benefit most from sentinel lymph node biopsy (SLNB) by investigating the characteristics and risk factors of axillary lymph node metastasis (ALNM) in microinvasive breast cancer (MIBC). METHODS: This retrospective study included 1688 patients with MIBC who underwent breast surgery with axillary staging at the Asan Medical Center from 1995 to 2020. RESULTS: Most patients underwent SLNB alone (83.5%). Seventy (4.1%) patients were node-positive, and the majority had positive lymph nodes < 10 mm, with micro-metastases occurring frequently (n = 37; 55%). Node-positive patients underwent total mastectomy and axillary lymph node dissection (ALND) more than breast-conserving surgery (BCS) and SLNB compared with node-negative patients (p < 0.001). In the multivariate analysis, independent predictors of ALNM included young age [odds ratio (OR) 0.959; 95% confidence interval (CI) 0.927-0.993; p = 0.019], ALND (OR 11.486; 95% CI 5.767-22.877; p < 0.001), number of lymph nodes harvested (≥ 5) (OR 3.184; 95% CI 1.555-6.522; p < 0.001), lymphovascular invasion (OR 6.831; 95% CI 2.386-19.557; p < 0.001), presence of multiple microinvasion foci (OR 2.771; 95% CI 1.329-5.779; p = 0.007), prominent lymph nodes in preoperative imaging (OR 2.675; 95% CI 1.362-5.253; p = 0.004), and hormone receptor positivity (OR 2.491; 95% CI 1.230-5.046; p = 0.011). CONCLUSION: Low ALNM rate (4.1%) suggests that routine SLNB for patients with MIBC is unnecessary but can be valuable for patients with specific risk factors. Ongoing trials for omitting SLNB in early breast cancer, and further subanalyses focusing on rare populations with MIBC are necessary.

5-aminosalicylic acid suppresses osteoarthritis through the OSCAR-PPARγ axis.

Osteoarthritis (OA) is a progressive and irreversible degenerative joint disease that is characterized by cartilage destruction, osteophyte formation, subchondral bone remodeling, and synovitis. Despite affecting millions of patients, effective and safe disease-modifying osteoarthritis drugs are lacking. Here we reveal an unexpected role for the small molecule 5-aminosalicylic acid (5-ASA), which is used as an anti-inflammatory drug in ulcerative colitis. We show that 5-ASA competes with extracellular-matrix collagen-II to bind to osteoclast-associated receptor (OSCAR) on chondrocytes. Intra-articular 5-ASA injections ameliorate OA generated by surgery-induced medial-meniscus destabilization in male mice. Significantly, this effect is also observed when 5-ASA was administered well after OA onset. Moreover, mice with DMM-induced OA that are treated with 5-ASA at weeks 8-11 and sacrificed at week 12 have thicker cartilage than untreated mice that were sacrificed at week 8. Mechanistically, 5-ASA reverses OSCAR-mediated transcriptional repression of PPARγ in articular chondrocytes, thereby suppressing COX-2-related inflammation. It also improves chondrogenesis, strongly downregulates ECM catabolism, and promotes ECM anabolism. Our results suggest that 5-ASA could serve as a DMOAD.

Dysbiosis of gut microbiota during fecal stream diversion in patients with colorectal cancer.

BACKGROUND: The effect of fecal stream diversion on the gut microbiota is still uncertain. The present study was designed to assess the effect of fecal stream diversion on the composition of the gut microbiota in patients with colorectal cancer. We included patients undergoing left-sided colorectal cancer surgery with (ileostomy group) or without (control group) diverting ileostomy. Fecal samples were collected from 10 patients in each group before surgery (t1) and after ileostomy repair in the ileostomy group and 6-12 months after the initial surgery in the control group (t2). The fecal microbiota was assessed using 16S rRNA sequencing, and changes in the composition of the fecal microbiota were compared between the two groups. RESULTS: Alpha diversity analysis revealed that the complexity of fecal microbiota decreased between t1 and t2 only in the ileostomy group. Beta diversity analysis also showed dissimilarity between t1 and t2 only in the ileostomy group. The composition of the microbiota was similar between the two groups at t1. However, at t2, the ileostomy group had lower proportion of beneficial bacteria (Lachnospiraceae, 3.8% vs. 29.9%, p < 0.001; Ruminococcaceae, 0.6% vs. 18.4%, p < 0.001; Blautia, 0.1% vs. 9.1%, p < 0.001; Faecalibacterium, 0.2% vs. 7.5%, p < 0.001) and a higher proportion of harmful bacteria (Proteobacteria, 17.9% vs. 5.1%, p = 0.006; Clostridium, 16.2% vs. 1.1%, p = 0.013; Streptococcus, 17.7% vs. 1.6%, p = 0.002) than the control group. CONCLUSIONS: Fecal stream diversion was closely associated with less diversity and dysbiosis of the gut microbiota.

Effect of preoperative immunonutrition on fecal microbiota in colon cancer patients: a secondary analysis of a randomized controlled trial.

BACKGROUND/OBJECTIVES: This study aimed to evaluate the effect of preoperative immunonutrition on the composition of fecal microbiota following a colon cancer surgery. MATERIALS/METHODS: This study was a secondary analysis of a randomized controlled trial assessing the impact of preoperative immunonutrition on the postoperative outcomes of colon cancer surgery. Patients with primary colon cancer were enrolled and randomly assigned to receive additional preoperative immunonutrition or a normal diet alone. Oral nutritional supplementation (400 mL/day) with arginine and ω-3 fatty acids were administered to patients in the immunonutrition group for 7 days prior to surgery. Thirty-two fecal samples were collected from 16 patients in each group, and the composition of fecal microbiota was compared between the 2 groups. RESULTS: At the phylum level, no significant difference was observed in the composition of microbiota between the 2 groups (Firmicutes, 69.1% vs. 67.5%, P = 0.624; Bacteroidetes, 19.3% vs. 18.1%, P = 0.663; Actinobacteria, 6.7% vs. 10.6%, P = 0.080). The Firmicutes/Bacteroidetes ratio (4.43 ± 2.32 vs. 4.55 ± 2.51, P = 0.897) was also similar between the 2 groups. At the genus level, the proportions of beneficial bacteria such as Faecalibacterium spp. (8.1% vs. 6.4%, P = 0.328) and Prevotella spp. (6.9% vs. 4.8%, P = 0.331) were higher, while that of Clostridium spp. was lower (0.5% vs. 1.2%, P = 0.121) in the immunonutrition group, but the difference was not significant. CONCLUSIONS: Immunonutrition showed no significant association with the composition of fecal microbiota. The relationship between immunonutrition and the fecal microbiota should be investigated further in large-scale studies.

Clinical significance of microinvasive breast cancer across the different subtypes and human epidermal growth factor receptor 2 expression levels.

PURPOSE: The clinical behavior, prognosis, and management of microinvasive breast cancer (MiBC) is controversial. We aimed to clarify its significance across different subtypes and the role of human epidermal growth factor receptor 2 (HER2) expression in MiBC. METHODS: We analyzed 1530 patients with T1mi (tumor size ≤ 0.1 cm), node-negative breast cancer who underwent breast conserving surgery or total mastectomy between 2001 and 2020 at the Asan Medical Center (AMC). RESULTS: When divided into four subtypes, hormone receptor (HR)+/HER2-, HR+ /HER2+ , HR-/HER2+ , and HR-/HER2-, HR-/HER2+ had the highest prevalence rate of 38.5% in MiBC patients. In a median follow-up period of 74 months (0-271 months), 103 (6.7%) patients had recurrent tumor, and 95 (6.2%) had local recurrence. Disease-free survival (DFS) and local recurrence-free survival (LRFS) were worst in the HR-/HER2+ group. The five-year DFS for the HR-/HER2+ group was 92.2%, while it was 97.1% for the HR+/HER2- group (p = 0.024 The five-year LRFS for HER2- patients were better than that of HER2+ MiBC patients, which were 97.1 and 93.8%, respectively (p = 0.010). Univariate and multivariate Cox regression analyses showed that the HR-/HER2+ group had relatively higher risk of recurrence compared to the HR+/HER2- group (hazard ratio [HR] = 2.332, 95% confidence interval [CI] 1.412-3.852, p = 0.001 unadjusted; HR = 3.346, 95% CI 1.408-7.953, p = 0.006 adjusted). CONCLUSION: HER2 overexpression was significantly associated with adverse clinicopathologic parameters and increased local recurrence risk in MiBC. Therefore, more understanding of the clinical behavior of HER2 in MiBC will enable tailoring of adjuvant therapy for these patients.

Impact of non-muscle cutting periumbilical transverse incision on the risk of incisional hernia as compared to midline incision during laparoscopic colon cancer surgery: a study protocol for a multi-centre randomised controlled trial.

BACKGROUND: Minimally invasive surgery has become popular as a surgical approach for colorectal cancer because it has fewer complications related to the abdominal incision and perioperative complications. However, the incidence of incisional hernias in laparoscopic surgery has been reported to be similar to that in open surgery. We developed a new method, the non-muscle-cutting periumbilical transverse incision, for a small incision in laparoscopic colon cancer surgery. This study aims to evaluate the effectiveness of the non-muscle-cutting periumbilical transverse incision in comparison with the midline incision in reducing the incidence of an incisional hernia in patients undergoing laparoscopic colon cancer surgery. METHODS: This is an open-label, multi-centre, parallel, superiority, and randomised trial. Altogether, 174 patients will be allocated in a 1:1 ratio to either the midline incision or the non-muscle-cutting periumbilical transverse incision group, after stratifying by the location of the tumour (right- or left-sided). The primary outcome of this study is the incidence of incisional hernias (both symptomatic and radiologic hernias) at 12 months after surgery. The secondary outcomes include operative outcomes, 30-day postoperative complications, pathological results, and patient-reported outcomes (short form-12 health survey questionnaire and body image questionnaire). Both primary (intention-to-treat) and secondary (as-treated principles) analyses will be performed for all outcomes. The statistical significance level was set at p < 0.05 (two-sided testing). DISCUSSION: This trial may show that the non-muscle-cutting periumbilical transverse incision will reduce the incidence of incisional hernias compared to the midline incision. TRIAL REGISTRATION: Clinical Research Information Service (CRiS) of Republic of Korea, KCT0006082 . Registered on April 12, 2021.

Impact of Preoperative Immunonutrition on the Outcomes of Colon Cancer Surgery: Results from a Randomized Controlled Trial.

OBJECTIVE: This study aimed to assess the impact of preoperative immunonutrition on the outcomes of colon cancer surgery. BACKGROUND: Although current guidelines recommend that immunonutrition should be prescribed for malnourished patients before major gastrointestinal surgery, the benefit of preoperative immunonutrition remains debatable. METHODS: Between April 2019 and October 2020, 176 patients with primary colon cancer were enrolled and randomly assigned (1:1) to receive preoperative immunonutrition plus a normal diet (n = 88) or a normal diet alone (n = 88). Patients in the immunonutrition group received oral nutritional supplementation (400 mL/d) with arginine and ω-3 fatty acids for 7 days before elective surgery. The primary endpoint was the rate of infectious complications, and the secondary endpoints were the postoperative complication rate, change in body weight, and length of hospital stay. RESULTS: The rates of infectious (17.7% vs 15.9%, P = 0.751) and total (31.6% vs 29.3%, P = 0.743) complications were not different between the two groups. Old age was the only significant predictive factor for the occurrence of infectious complications (odds ratio = 2.990, 95% confidence interval 1.179-7.586, P = 0.021). The length of hospital stay (7.6 ± 2.5 vs 7.4 ± 2.3 days, P = 0.635) and overall change in body weight ( P = 0.379) were similar between the two groups. However, only the immunonutrition group showed weight recovery after discharge (+0.4 ± 2.1 vs -0.7 ± 2.3 kg, P = 0.002). CONCLUSIONS: Preoperative immunonutrition was not associated with infectious complications in patients undergoing colon cancer surgery. Routine administration of immunonutrition before colon cancer surgery cannot be justified.

Deep Learning Enhances Multiparametric Dynamic Volumetric Photoacoustic Computed Tomography In Vivo (DL-PACT).

Photoacoustic computed tomography (PACT) has become a premier preclinical and clinical imaging modality. Although PACT's image quality can be dramatically improved with a large number of ultrasound (US) transducer elements and associated multiplexed data acquisition systems, the associated high system cost and/or slow temporal resolution are significant problems. Here, a deep learning-based approach is demonstrated that qualitatively and quantitively diminishes the limited-view artifacts that reduce image quality and improves the slow temporal resolution. This deep learning-enhanced multiparametric dynamic volumetric PACT approach, called DL-PACT, requires only a clustered subset of many US transducer elements on the conventional multiparametric PACT. Using DL-PACT, high-quality static structural and dynamic contrast-enhanced whole-body images as well as dynamic functional brain images of live animals and humans are successfully acquired, all in a relatively fast and cost-effective manner. It is believed that the strategy can significantly advance the use of PACT technology for preclinical and clinical applications such as neurology, cardiology, pharmacology, endocrinology, and oncology.

Anastomotic leak after minimally invasive anterior resection for rectal cancer with high versus low ligation of the inferior mesenteric artery: a study protocol for a multicentre randomized clinical trial.

BACKGROUND: Although many efforts have been made to decrease the incidence of anastomotic leak (AL), it remains one of the most serious complications of rectal cancer surgery. Many previous studies have reported an association between the ligation level of the inferior mesenteric artery (IMA) (high or low) and the incidence of AL after rectal cancer surgery. However, we cannot draw a solid conclusion because of the low quality and heterogeneity of those studies. Therefore, this study aims to investigate the impact of the IMA ligation level on the occurrence of AL after minimally invasive anterior resection of rectal cancer. METHODS/DESIGN: Patients with primary rectal cancer without distant metastases will be included after screening. They will be randomly assigned (1:1) to receive high or low ligation of the IMA. The primary endpoint is AL incidence; secondary endpoints are quality of life; urinary, sexual, and defecatory functions; and 3-year disease-free survival. We hypothesized that the incidence rate of AL would be 15% and 5% in the high- and low-ligation groups, respectively. With a two-sided α of 0.05 and a power of 0.8, the sample size is calculated to be 314 patients (157 per group), considering a 10% dropout rate. DISCUSSION: Although many studies have compared the short- and long-term outcomes of high and low ligation of the IMA in rectal cancer surgery, it is still debatable. This trial aims to help draw a more solid conclusion regarding the association between the IMA ligation level and AL incidence after rectal cancer surgery. We also hope to contribute to standardizing the method of rectal cancer surgery in this trial. TRIAL REGISTRATION: Clinical Research Information Service KCT0003523. Registered on February 18, 2019.

Pim1 promotes IFN-ß production by interacting with IRF3.

The Pim (proviral integration site for Moloney murine leukemia virus) proteins compose a serine threonine kinase family whose members regulate cell proliferation, migration and cell survival. However, whether Pim kinases participate in innate immune responses is unclear. Here, we show for the first time that Pim1 plays an essential role in the production of interferon (IFN)-ß by macrophages after their Toll-like receptor (TLR) pathway is activated by pathogen-associated molecular patterns (PAMPs). Specifically, Pim1 was quickly upregulated in an NF-κB-dependent manner after TLR stimulation with PAMPs. Pim1 deficiency reduced TLR3- or TLR4-stimulated IFN-ß and IFN-stimulated gene (ISG) expression but not proinflammatory cytokine expression in macrophages. Mechanistically, Pim1 specifically upregulates IRF3 phosphorylation and nuclear translocation. However, this role is not dependent on Pim1 kinase activity. Rather, Pim1 appears to promote IRF3 phosphorylation by enhancing the formation of IFN-ß signaling complexes composed of TRIF, TRAF3, TBK1, and IRF3. Poly (I:C)-treated Pim1-/- mice produced less serum IFN-ß and were less likely to survive than wild-type mice. These findings show for the first time that Pim1 participates in TLR-mediated IFN-ß production, thus revealing a novel target for controlling antiviral innate immune responses.

Association between microsatellite instability and tumor response to neoadjuvant chemoradiotherapy for rectal cancer.

Purpose: The relationship between microsatellite instability (MSI) and tumor response after neoadjuvant chemoradiotherapy (nCRT) in rectal cancer remains unclear. The present study aimed to evaluate the association between MSI and tumor response to nCRT in rectal cancer treatment. Methods: Patients with rectal cancer from 2 tertiary hospitals who underwent nCRT, followed by radical surgery, were included. The microsatellite status was determined using a PCR-based Bethesda panel. Tumors with a Dworak's tumor regression grade of 3 or 4 were considered to have a good response. Predictive factors for a good response to nCRT were analyzed. Results: Of the 1,401 patients included, 910 (65.0%) had MSI results and 1.5% (14 of 910) showed MSI-H. Among all the patients, 519 (37.0%) showed a good response to nCRT. A univariate analysis showed that MSI-H tended to be negatively associated with a good response to nCRT, but no statistical significance was observed (7.1% vs. 24.1%, P = 0.208). Multivariate analysis showed that well-differentiated tumors were the only predictive factor for good response to nCRT (odds ratio [OR], 2.241; 95% confidence interval [CI], 1.492-3.364; P < 0.001). MSI status tended to be associated with the response to nCRT (OR, 0.215; 95% CI, 0.027-1.681; P = 0.143). Conclusion: MSI-H was not associated with response to nCRT in patients with rectal cancer.

Impact of circumferential tumor location of mid to low rectal cancer on oncologic outcomes after preoperative chemoradiotherapy.

Purpose: Some studies have suggested that circumferential tumor location (CTL) of rectal cancer may affect oncological outcomes. However, studies after preoperative chemoradiotherapy (CRT) are rare. This study aimed to evaluate the impact of CTL on oncologic outcomes of patients with mid to low rectal cancer who received preoperative CRT. Methods: Patients with mid to low rectal cancer who underwent total mesorectal excision after CRT from January 2013 to December 2018 were included in this retrospective study. The impact of CTL on the pathological circumferential resection margin (CRM) status, local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS) was analyzed. Results: Of the 381 patients, 98, 70, 127, and 86 patients were categorized into the anterior, posterior, lateral, and circumferential tumor groups, respectively. Tumor location was not significantly associated with the pathological CRM involvement (anterior, 12.2% vs. posterior, 14.3% vs. lateral, 11.0% vs. circumferential, 17.4%; P = 0.232). Univariate analyses revealed no correlation between CTL and 3-year LRFS (93.0% vs. 89.1% vs. 91.5% vs. 88%, P = 0.513), 3-year DFS (70.3% vs. 70.2% vs. 75.3% vs. 75.7%, P = 0.832), and 5-year OS (74.7% vs. 78.0% vs. 83.9% vs. 78.2%, P = 0.204). Multivariate analysis identified low rectal cancer and pathological CRM involvement as independent risk factors for all survival outcomes (all P < 0.05). Conclusion: CTL of rectal cancer after preoperative CRT was not significantly associated with the pathological CRM status, recurrence, and survival.

Effect of the First Assistant on Anastomotic Leakage after Rectal Cancer Surgery with Double-Stapling Anastomosis: A Propensity Score Matching Analysis.

INTRODUCTION: Proper handling and firing of the circular stapler are important for secure anastomosis in rectal cancer surgery. This study aimed to investigate the association between the first assistant and anastomotic leakage (AL) after rectal cancer surgery with double-stapling anastomosis. METHODS: Patients with primary rectal cancer who underwent low anterior resection with double-stapling anastomosis between January 2015 and September 2019 were included. Data on clinicopathological characteristics, including the first assistant's sex and experience level, were retrospectively reviewed, and the risk factors for AL were analyzed using propensity score matching analysis. RESULTS: Among 758 rectal cancer surgeries, residents participated in 401 (52.9%) surgeries, and fellows participated in 357 (47.1%) surgeries as first assistants. After propensity score matching (n = 650), AL occurred in 5.4% (35/650). The first assistant's experience level (resident: 5.5% vs. fellow: 5.2%, p = 0.862) and sex (male: 5.4% vs. female: 4.9%, p = 0.849) were not associated with the occurrence of AL. Male sex in patients was the only significant predictive factor for AL (odds ratio = 2.804, 95% confidence interval 1.070-7.351, p = 0.036). DISCUSSION/CONCLUSION: The first assistant's sex and experience level were not associated with AL after rectal cancer surgery with double-stapling anastomosis. These findings may justify resident participation in rectal cancer surgeries in which circular staplers are used.

BCAT1 promotes osteoclast maturation by regulating branched-chain amino acid metabolism.

Branched-chain aminotransferase 1 (BCAT1) transfers the amine group on branched-chain amino acids (BCAAs) to alpha-ketoglutarate. This generates glutamate along with alpha-keto acids that are eventually oxidized to provide the cell with energy. BCAT1 thus plays a critical role in sustaining BCAA concentrations and availability as an energy source. Osteoclasts have high metabolic needs during differentiation. When we assessed the levels of amino acids in bone marrow macrophages (BMMs) that were undergoing receptor activator of nuclear factor κB ligand (RANKL)-induced osteoclast differentiation, we found that the BCAA levels steadily increase during this process. In vitro analyses then showed that all three BCAAs but especially valine were needed for osteoclast maturation. Moreover, selective inhibition of BCAT1 with gabapentin significantly reduced osteoclast maturation. Expression of enzymatically dead BCAT1 also abrogated osteoclast maturation. Importantly, gabapentin inhibited lipopolysaccharide (LPS)-induced bone loss of calvaria in mice. These findings suggest that BCAT1 could serve as a therapeutic target that dampens osteoclast formation.

Identification of genetic mutations of cutaneous squamous cell carcinoma using whole exome sequencing in non-Caucasian population.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is the second most common nonmelanoma skin cancer worldwide. Recent studies have reported several genetic mutations in development of cSCC such as TP53, HRAS, and NOTCH1. Whole-exome sequencing (WES) of cSCC has not been reported in East Asian populations. OBJECTIVE: We aimed to investigate genetic mutations of cSCCs in Korean patients by WES. METHODS: cSCCs and paired peripheral blood samples were obtained from 19 Korean patients who underwent wide excision on the cheek from 2016 to 2020 and divided into moderate to poor-differentiated (MP-D) cSCCs (n = 9) and well-differentiated (W-D) cSCCs (n = 10) according to the histopathological evaluation. WES was performed for analysis of genomic mutations of cSCCs. RESULTS: The mean total mutation burden of MP-D cSCCs was higher than W-D cSCCs. Also, we observed proportionately more driver mutations in MP-D cSCC than W-D cSCC groups. CSMD3, COL22A1, FMN2, and ASXL3 mutations are highly frequent than the results of previous reports in cSCC of Caucasians. CONCLUSION: These results may aid in further our understanding of the complex process underlying tumorigenesis of cSCC in non-Caucasian populations.

Periumbilical Transverse Incision for Reducing Incisional Hernia in Laparoscopic Colon Cancer Surgery.

BACKGROUND: Although off-midline incisions (unilateral low transverse or Pfannenstiel incision) have been reported to have a lower incidence of incisional hernia (IH) than periumbilical vertical incision for the purpose of specimen extraction, it is most commonly used in laparoscopic colon cancer surgery because off-midline incisions are associated with the limitation of colon exteriorization. This study aims to investigate the risk of IH after laparoscopic colectomy and compare midline vertical incision versus transverse incision focusing on the incidence of IH. METHODS: Patients who underwent elective laparoscopic colectomy due to colon malignancy from June 2015 to May 2017 were included. All patients had either vertical (n = 429) or muscle splitting periumbilical transverse incisions (n = 125). RESULTS: Median duration of the follow-up period was 23.6 months, during which IHs occurred in 12.1% patients. The incidence of hernia was significantly lower in the transverse group (3 vs. 64, 2.4% vs. 14.9%, p < 0.001). On multivariate analysis, BMI ≥ 23 [odds ratio (OR) 2.282, 95% confidence interval (CI) 1.245-4.182, p = 0.008], postoperative surgical site infection (OR 3.780, 95% CI 1.969-7.254, p < 0.001) and vertical incision (OR 7.113, 95% CI 2.173-23.287, p < 0.001) were independently related with increased incidence of IH. CONCLUSIONS: A muscle splitting periumbilical transverse incision could significantly reduce the rate of IH in minimally invasive colon cancer surgery.

Proper surgical extent for clinical Stage I right colon cancer.

PURPOSE: Pre-operative evaluation identifying clinical-stage affects the decision regarding the extent of surgical resection in right colon cancer. This study was designed to predict a proper surgical resection through the prognosis of clinical Stage I right colon cancer. PATIENTS AND METHODS: We included patients who were diagnosed with clinical and pathological Stage I right-sided colon cancer, including appendiceal, caecal, ascending, hepatic flexure and proximal transverse colon cancer, between August 2010 and December 2016 in two tertiary teaching hospitals. Patients who underwent open surgeries were excluded because laparoscopic surgery is the initial approach for colorectal cancer in our institutions. RESULTS: Eighty patients with clinical Stage I and 104 patients with pathological Stage I were included in the study. The biopsy reports showed that the tumour size was larger in the clinical Stage I group than in the pathological Stage I group (3.4 vs. 2.3 cm, P < 0.001). Further, the clinical Stage I group had some pathological Stage III cases (positive lymph nodes, P = 0.023). The clinical Stage I group had a higher rate of distant metastases (P = 0.046) and a lower rate of overall (P = 0.031) and cancer-specific survival (P = 0.021) than the pathological Stage I group. Compared to pathological Stage II included in the period, some of the survival curves were located below the pathological Stage II, but there was no statistical difference. CONCLUSION: The study results show that even clinical Stage I cases, radical resection should be considered in accordance with T3 and T4 tumours.

Tetraspanin 7 regulates osteoclast function through association with the RANK/αvß3 integrin complex.

Actin rings are unique structures that facilitate the attachment of osteoclasts to the bone matrix during bone resorption. Previous studies have shown that tetraspanin7 (TSPAN7) plays an important role in the reorganization of the cytoskeleton necessary for the bone-resorbing activity of osteoclasts. However, questions remain as to the mechanisms by which TSPAN7 regulates this cytoskeletal rearrangement. In this study, we investigated the roles of TSPAN7 in osteoclasts by deleting the Tm4sf2 gene in mice, which encodes TSPAN7. The Tm4sf2 global knockout model showed protective effects on pathological bone loss, but no discernible changes in bone phenotypes under physiological conditions. In vitro study revealed that ablation of Tm4sf2 caused significant defects in integrin-mediated actin ring formation, thereby leading to significantly decreased bone resorption. Additionally, we demonstrated an association between TSPAN7 and the receptor activator of nuclear factor-кB/αvß3 integrin. Overall, our findings suggest that TSPAN7 acts as a novel modulator regulating the bone-resorbing function of osteoclasts.

Postoperative bile leakage caused by intrahepatic duct injury during right hemicolectomy: A case report.

INTRODUCTION: Bile peritonitis is one of the rare complications that can occur after cholecystectomy or hepatectomy. It is associated with high mortality, prolonged hospital stay, and increased cost. We herein report 2 cases of bile leakage as a postoperative complication of right hemicolectomy. PATIENT CONCERNS: Two patients underwent a right hemicolectomy for colon cancer. Both patients had a history of cholecystectomy, and intrahepatic bile duct dilatation was observed in preoperative imaging study. During surgery, adhesiolysis was performed between the liver and the hepatic flexure of the colon due to adhesion in that area. DIAGNOSIS: Postoperatively, bile fluid was drained via an intraabdominal drainage tube. Both cases required surgical intervention to explore the origin of the leakage. In both cases, the anastomosis was intact, and the injury of the intrahepatic bile duct just beneath the liver surface was the origin of bile leakage. INTERVENTIONS: Suture ligation, irrigation, and drainage were performed in both patients. OUTCOMES: There was no more bile leakage after reoperation, and both patients were discharged in good health after antibiotics treatment. CONCLUSION: Although very rare, bile leakage due to intrahepatic duct injury can occur after right hemicolectomy in patients with a history of cholecystectomy and intrahepatic duct dilatation. It is necessary to consider the possibility of bile duct injury and anastomotic leakage if bile leakage is suspected after right hemicolectomy.