Moderating AKT signaling with baicalein protects against weight loss by preventing muscle atrophy in a cachexia model caused by CT26 colon cancer.

Cancer cachexia is a type of energy-wasting syndrome characterized by fatigue, anorexia, muscle weakness, fat loss, and systemic inflammation. Baicalein, a flavonoid with bioactive properties, has demonstrated the ability to mitigate cardiac and skeletal muscle atrophy in different experimental settings. This effect is achieved through the inhibition of muscle proteolysis, suggesting its potential in preserving skeletal muscle homeostasis. In this study, we investigated the anti-cancer cachexia effects of baicalein in the regulation of muscle and fat wasting, both in vivo and in vitro. Baicalein attenuated body weight loss, including skeletal muscle and white adipose tissue (WAT), in CT26-induced cachectic mice. Moreover, baicalein increased muscle fiber thickness and suppressed the muscle-specific ubiquitin-protease system, including F-box only protein 32 and muscle RING-finger protein-1, by activating AKT phosphorylation both in vivo and in vitro. The use of LY294002, a particular inhibitor of AKT, eliminated the observed impact of baicalein on the improvement of muscle atrophy. In conclusion, baicalein inhibits muscle proteolysis and enhances AKT phosphorylation, indicating its potential role in cancer cachexia-associated muscle atrophy.

Effect of multimodal intervention care on cachexia in patients with advanced cancer compared to conventional management (MIRACLE): an open-label, parallel, randomized, phase 2 trial.

BACKGROUND: Cancer cachexia (CC) is a multifactorial process characterized by progressive weight loss, muscle mass, and fat tissue wasting, which adversely affects the quality of life and survival of patients with advanced stages of cancer. CC has a complex and multifactorial pathophysiology, and there is no established standard treatment. Therefore, it is often irreversible and a single treatment modality is unlikely to suppress its progression. We are conducting a randomized trial to investigate the efficacy and safety of a multimodal intervention compared to the best supportive care for patients who received palliative chemotherapy. METHODS: Patients with lung or gastrointestinal cancers undergoing palliative chemotherapy are eligible. Patients are randomized into a multimodal intervention care (MIC) arm versus a conventional palliative care (CPC) arm. MIC includes ibuprofen, omega-3-fatty acid, oral nutritional supplement, weekly physical, psychiatric assessment, nutritional counseling, and complementary and alternative medicine. CPC includes basic nutritional counseling and megestrol acetate as needed (i.e., anorexia ≥ grade 2). All interventions are performed for 12 weeks per subject. The co-primary outcomes are change (kg) in total lean body mass and handgrip strength (kg) from the baseline. A total of 112 patients will be assigned to the two arms (56 in each group). DISCUSSION: The purpose of this study is to evaluate the effect of MIC in preventing or alleviating CC in patients who underwent palliative chemotherapy. As there is no established single treatment for CC, it is expected that the results of this clinical trial will provide new insights to significantly improve the quality of life of patients with cancer. Considering the complex mechanisms of cachexia, the effect of MIC rather than a single specific drug is more promising. In this study, we did not overly restrict the type of cancer or chemotherapy. Therefore, we attempted to measure the effects of complex interventions while preserving clinical situations. Thus, it is expected that the results of this study can be applied effectively to real-world practice. TRIAL REGISTRATION: This clinical trial was registered in the Clinical Research Information Service (KCT0004967), Korean Clinical Trial Registry on April 27, 2020, and ClinicalTrial.gov (NCT04907864) on June 1, 2021.

Molecular characterization of dysplasia-initiated colorectal cancer with assessing matched tumor and dysplasia samples.

PURPOSE: Ulcerative colitis (UC) is known to have an association with the increased risk of colorectal cancer (CRC), and UC-associated CRC does not follow the typical progress pattern of adenoma-carcinoma. The aim of this study is to investigate molecular characteristics of UC-associated CRC and further our understanding of the association between UC and CRC. METHODS: From 5 patients with UC-associated CRC, matched normal, dysplasia, and tumor specimens were obtained from formalin-fixed paraffin-embedded (FFPE) samples for analysis. Genomic DNA was extracted and whole exome sequencing was conducted to identify somatic variations in dysplasia and tumor samples. Statistical analysis was performed to identify somatic variations with significantly higher frequencies in dysplasia-initiated tumors, and their relevant functions were investigated. RESULTS: Total of 104 tumor mutation genes were identified with higher mutation frequencies in dysplasia-initiated tumors. Four of the 5 dysplasia-initiated tumors (80.0%) have TP53 mutations with frequent stop-gain mutations that were originated from matched dysplasia. APC and KRAS are known to be frequently mutated in general CRC, while none of the 5 patients have APC or KRAS mutation in their dysplasia and tumor samples. Glycoproteins including mucins were also frequently mutated in dysplasia-initiated tumors. CONCLUSION: UC-associated CRC tumors have distinct mutational characteristics compared to typical adenoma-carcinoma tumors and may have different cancer-driving molecular mechanisms that are initiated from earlier dysplasia status.

Is Laparoscopic Complete Mesocolic Excision and Central Vascular Ligation Really Necessary for All Patients With Right-Sided Colon Cancer?

Colon cancer treatment is on the way to evolution over several decades. The minimally invasive surgery has improved postoperative short-term outcomes. Adjuvant chemotherapy has prolonged the survival of advanced colon cancer patients. Hohenberger proposed the noble concept of complete mesocolic excision (CME) which consists of 3 components: plane surgery, sufficient longitudinal bowel resection, and central vascular ligation (CVL). Mesocolic plane surgery shares the same surgical principle of total mesorectal excision, which is maintaining the intact mesothelial envelope. However, there remain debates about the extent of bowel resection and the level of CVL for maximizing lymph node dissection. There is no solid clinical evidence for the oncological necessity and benefit of extended radical dissection in right hemicolectomy. CME with CVL based on open surgery has been adopted in laparoscopic surgery. So, it is also necessary to look at how the CME could be transformed and successfully implanted in the laparoscopic era. Recent rapid advances in surgical technology and cancer biology are preparing for fundamental changes in cancer surgery. In this study, we reviewed the history, oncological necessity, and compatibility of CME for the right hemicolectomy in the laparoscopic era and outline the new perspectives on the evolution of cancer surgery.

Bone Marrow Homeostasis Is Impaired via JAK/STAT and Glucocorticoid Signaling in Cancer Cachexia Model.

Cancer cachexia is a multifactorial systemic inflammation disease caused by complex interactions between the tumor and host tissues via soluble factors. However, whether cancer cachexia affects the bone marrow, in particular the hematopoietic stem cells (HSCs) and mesenchymal stem cells (MSCs), remains unclear. Here, we investigated the bone marrow and bone in a cancer cachexia animal model generated by transplanting Lewis lung carcinoma cells. The number of bone marrow mononuclear cells (BM-MNCs) started to significantly decrease in the cancer cachectic animal model prior to the discernable loss of muscle and fat. This decrease in BM-MNCs was associated with myeloid skewing in the circulation and the expansion of hematopoietic progenitors in the bone marrow. Bone loss occurred in the cancer cachexia animal model and accompanied the decrease in the bone marrow MSCs that play important roles in both supporting HSCs and maintaining bone homeostasis. Glucocorticoid signaling mediated the decrease in bone marrow MSCs in the cancer cachectic environment. The cancer cachexia environment also skewed the differentiation of the bone marrow MSCs toward adipogenic fate via JAK/STAT as well as glucocorticoid signaling. Our results suggest that the bone loss induced in cancer cachexia is associated with the depletion and the impaired differentiation capacity of the bone marrow MSCs.

A Proteomic Approach to Understand the Clinical Significance of Acute Myeloid Leukemia-Derived Extracellular Vesicles Reflecting Essential Characteristics of Leukemia.

Extracellular vesicle (EV) proteins from acute myeloid leukemia (AML) cell lines were analyzed using mass spectrometry. The analyses identified 2450 proteins, including 461 differentially expressed proteins (290 upregulated and 171 downregulated). CD53 and CD47 were upregulated and were selected as candidate biomarkers. The association between survival of patients with AML and the expression levels of CD53 and CD47 at diagnosis was analyzed using mRNA expression data from The Cancer Genome Atlas database. Patients with higher expression levels showed significantly inferior survival than those with lower expression levels. ELISA results of the expression levels of CD53 and CD47 from EVs in the bone marrow of patients with AML at diagnosis and at the time of complete remission with induction chemotherapy revealed that patients with downregulated CD53 and CD47 expression appeared to relapse less frequently. Network model analysis of EV proteins revealed several upregulated kinases, including LYN, CSNK2A1, SYK, CSK, and PTK2B. The potential cytotoxicity of several clinically applicable drugs that inhibit these kinases was tested in AML cell lines. The drugs lowered the viability of AML cells. The collective data suggest that AML cell-derived EVs could reflect essential leukemia biology.

Comparative lipidomics of 5-Fluorouracil-sensitive and -resistant colorectal cancer cells reveals altered sphingomyelin and ceramide controlled by acid sphingomyelinase (SMPD1).

5-Fluorouracil (5-FU) is a chemotherapeutic drug widely used to treat colorectal cancer. 5-FU is known to gradually lose its efficacy in treating colorectal cancer following the acquisition of resistance. We investigated the mechanism of 5-FU resistance using comprehensive lipidomic approaches. We performed lipidomic analysis on 5-FU-resistant (DLD-1/5-FU) and -sensitive (DLD-1) colorectal cancer cells using MALDI-MS and LC-MRM-MS. In particular, sphingomyelin (SM) species were significantly up-regulated in 5-FU-resistant cells in MALDI-TOF analysis. Further, we quantified sphingolipids including SM and Ceramide (Cer) using Multiple Reaction Monitoring (MRM), as they play a vital role in drug resistance. We found that 5-FU resistance in DLD-1/5-FU colorectal cancer cells was mainly associated with SM increase and Cer decrease, which are controlled by acid sphingomyelinase (SMPD1). In addition, reduction of SMPD1 expression was confirmed by LC-MRM-MS analysis and the effect of SMPD1 in drug resistance was assessed by treating DLD-1 cells with siRNA-SMPD1. Furthermore, clinical colorectal cancer data set analysis showed that down-regulation of SMPD1 was associated with resistance to chemotherapy regimens that include 5-FU. Thus, from our study, we propose that SM/Cer and SMPD1 are new potential target molecules for therapeutic strategies to overcome 5-FU resistance.

Laparoscopic Surgery for Colorectal Cancer in Korea: Nationwide Data from 2013 to 2018.

PURPOSE: We report nationwide data on the current status of laparoscopic surgery for colorectal cancer (CRC) in Korea. MATERIALS AND METHODS: Nationwide data of patients who underwent surgery for CRC from 2013 to 2018 were obtained from the Health Insurance Review & Assessment Service database. Data and trends of laparoscopy use for colorectal resection over six years were examined. RESULTS: In Korea, a total of 117,320 patients underwent surgical resection for CRC from 2013 to 2018. The proportion of laparoscopic resection increased from 64.9% in 2013 to 78.5% in 2018. The rate of laparoscopic resection for colon cancer increased from 64.7% in 2013 to 77.4% in 2018. For rectal cancer, the rate of laparoscopic resection increased from 65.4% to 81.6%. Males accounted for 59.8% of all patients, but females surpassed males at over 80 years of age. The age of peak incidence was in the 60s for males and in the 70s for females. A steady increase in the number of patients undergoing surgery for CRC was observed over 80 years of age. CONCLUSION: The laparoscopic penetration rate for CRC in Korea continued to increase annually and reached 78.5% in 2018.

APSIC guidelines for the prevention of surgical site infections.

Background: The Asia Pacific Society of Infection Control (APSIC) launched the APSIC Guidelines for the Prevention of Surgical Site Infections in 2018. This document describes the guidelines and recommendations for the setting prevention of surgical site infections (SSIs). It aims to highlight practical recommendations in a concise format designed to assist healthcare facilities at Asia Pacific region in achieving high standards in preoperative, perioperative and postoperative practices. Method: The guidelines were developed by an appointed workgroup comprising experts in the Asia Pacific region, following reviews of previously published guidelines and recommendations relevant to each section. Results: It recommends that healthcare facilities review specific risk factors and develop effective prevention strategies, which would be cost effective at local levels. Gaps identified are best closed using a quality improvement process. Surveillance of SSIs is recommended using accepted international methodology. The timely feedback of the data analysed would help in the monitoring of effective implementation of interventions. Conclusions: Healthcare facilities should aim for excellence in safe surgery practices. The implementation of evidence-based practices using a quality improvement process helps towards achieving effective and sustainable results.

Definition of the Rectum: An International, Expert-based Delphi Consensus.

BACKGROUND: The wide global variation in the definition of the rectum has led to significant inconsistencies in trial recruitment, clinical management, and outcomes. Surgical technique and use of preoperative treatment for a cancer of the rectum and sigmoid colon are radically different and dependent on the local definitions employed by the clinical team. A consensus definition of the rectum is needed to standardise treatment. METHODS: The consensus was conducted using the Delphi technique with multidisciplinary colorectal experts from October, 2017 to April, 2018. RESULTS: Eleven different definitions for the rectum were used by participants in the consensus. Magnetic resonance imaging (MRI) was the most frequent modality used to define the rectum (67%), and the preferred modality for 72% of participants. The most agreed consensus landmark (56%) was "the sigmoid take-off," an anatomic, image-based definition of the junction of the mesorectum and mesocolon. In the second round, 81% of participants agreed that the sigmoid take-off as seen on computed tomography or MRI achieved consensus, and that it could be implemented in their institution. Also, 87% were satisfied with the sigmoid take-off as the consensus landmark. CONCLUSION: An international consensus definition for the rectum is the point of the sigmoid take-off as visualized on imaging. The sigmoid take-off can be identified as the mesocolon elongates as the ventral and horizontal course of the sigmoid on axial and sagittal views respectively on cross-sectional imaging. Routine application of this landmark during multidisciplinary team discussion for all patients will enable greater consistency in tumour localisation.

Postoperative Outcomes of Stoma Takedown: Results of Long-term Follow-up.

PURPOSE: Stoma takedown is a frequently performed procedure with considerable postoperative morbidities. Various skin closure techniques have been introduced to reduce surgical site infections. The aim of this study was to assess postoperative outcomes after stoma takedown during a long-term follow-up period. METHODS: Between October 2006 and December 2015, 84 consecutive patients underwent a colostomy or ileostomy takedown at our institution. Baseline characteristics and perioperative outcomes were analyzed through retrospective reviews of medical records. RESULTS: The proportion of male patients was 60.7%, and the mean age of the patients was 59.0 years. The overall complication rate was 28.6%, with the most common complication being prolonged ileus, followed by incisional hernia, anastomotic leakage, surgical site infection, anastomotic stenosis, and entero-cutaneous fistula. The mean follow-up period was 64.3 months. The univariate analysis revealed no risk factors related to overall complications or prolonged ileus. CONCLUSION: The postoperative clinical course and long-term outcomes following stoma takedown were acceptable. Stoma takedown is a procedure that can be performed safely.

Colonoscopy education for surgical residents in Korea: a national survey of Korean Surgical Skill Study Group.

PURPOSE: A standardized colonoscopy training program surgical residents is still unestablished. The aim of this study was to assess the current status of colonoscopy training for surgical residents and collect the opinions on the direction for future colonoscopy education. METHODS: A questionnaire survey containing 24 items was conducted by sending an email to 310 colorectal surgeons in 84 training hospitals across the country. RESULTS: One hundred fifteen staff surgeons (115 of 310, 37%) of 84 institutions returned fully completed questionnaires. Most surgeons were working at tertiary hospitals with more than 5 years of clinical experience. About half of the responding surgeons answered that they perform colonoscopy in clinical practice and the main purpose of colonoscopy was follow-up after colorectal resection. Only 9 of 84 hospitals (10.7%) had a regular program on colonoscopy training for surgical residents. Most of colonoscopy education was conducted irregularly in a form of staff lecture, conferences or hands-on workshops. According to the future directions, 72 of 115 surgeons (62.6%) answered judging competency in colonoscopy should be needed for professional qualification of the surgeon. About 50 cases of colonoscopy seem appropriate during the 4-year-training of surgical residency, especially during the third- and fourth-year. CONCLUSION: This survey shows colonoscopy education for surgical residents is still insufficient in Korea and that most surgeons feel that regular colonoscopy training is needed during the surgical residency period. There needs to be efforts to standardize the education program as well as various institutional and academic societal supports to achieve this goal.

Current Status and Trends in Inflammatory Bowel Disease Surgery in Korea: Analysis of Data in a Nationwide Registry.

PURPOSE: Inflammatory bowel disease (IBD) in Korea has been increasing in recent years, but accurate statistics about operations for IBD are lacking. The purpose of this study was to investigate the trends and current status of IBD surgeries in Korea. METHODS: Using a national database from the Korea Health Insurance Review and Assessment Service, we analyzed data from patients who underwent surgery for Crohn disease and ulcerative colitis from January 2009 to October 2016. RESULTS: The mean number of patients who underwent surgery for Crohn disease was 791.8 per year. Colorectal surgery, small bowel surgery, and anal surgery were performed fairly often (31.2%, 29.4%, 39.4%, respectively), and laparoscopic surgery continued to increase, recently exceeding 30%. About 50% of Crohn patients used biologics before and after surgery, and those patients also underwent a relatively high rate of anal surgeries (44.2%). The mean number of patients who underwent surgery for ulcerative colitis was 247.6 per year. Colorectal surgery accounted for more than half of all operations, and laparoscopic surgery has been increasing rapidly, having been performed in about 60% of patients in recent years. The incidence of colorectal cancer in patients with ulcerative colitis was very high and increased rapidly during the study period, reaching about 80%. CONCLUSION: The number of patients undergoing laparoscopic surgery for IBD in Korea has increased significantly. Biologics are actively used by patients with Crohn disease, with a high proportion of anal surgeries required. Many of the surgical indications for ulcerative colitis have shifted into colorectal cancer.

Multicenter, randomized single-port versus multiport laparoscopic surgery (SIMPLE) trial in colon cancer: an interim analysis.

BACKGROUND: Single-port laparoscopic surgery (SPLS) was recently introduced as an innovative minimally invasive surgery method. Retrospective studies have revealed the safety and feasibility of SPLS for colon cancer treatment. However, no prospective randomized trials have been performed. The multicenter, randomized SIMPLE (single-port versus multiport laparoscopic surgery) trial aimed to investigate short-term perioperative outcomes of SPLS for colon cancer treatment, compared with multiport laparoscopic surgery (MPLS). METHODS: Between August 2011 and April 2014, a total of 194 patients with colon cancer were recruited from seven hospitals in Korea. Patients were randomly allocated into the SPLS group (n = 99) or MPLS group (n = 95). The primary endpoint was postoperative complications. Operative, postoperative, and pathologic outcomes were analyzed after 50% of the patient study population had been recruited. RESULTS: The patients' demographic characteristics, operative times, estimated blood volume losses, numbers of harvested lymph nodes, and lengths of both resection margins were not significantly different between groups. In the SPLS group, the rates of conversion to MPLS and open surgery were 12.9 and 2.2%, respectively. Postoperative complications occurred in 10.8% of the SPLS, and 12.5% of the MPLS patients (p = 0.714). Times to functional recovery, pain scores, and amounts of analgesia were similar between groups. CONCLUSION: The results of this interim analysis suggested that SPLS is technically safe and appropriate when used for radical resection of colon cancer. (ClinicalTrials.gov Identifier: NCT01480128).

Does circumferential tumor location affect the circumferential resection margin status in mid and low rectal cancer?

BACKGROUND/OBJECTIVE: The purpose of this study was to assess the impact of circumferential tumor location on circumferential resection margin (CRM) status and the depth of tumor invasion in mid and low rectal cancer. METHODS: We retrospectively analyzed whole-mount slides of 58 patients who underwent total mesorectal excision for mid and low rectal cancer. The rate of tumor-positive CRM was compared according to the circumferential tumor location. In 31 patients, morphometric analyses of whole-mount specimens were performed to measure the depth of tumor invasion according to circumferential tumor location. RESULTS: Among 58 patients, 50% of tumors were anterior tumor and 50% were nonanterior. A tumor-positive CRM was more observed frequently in anterior tumors than in nonanterior tumors (41.1% vs. 10.3%, p = 0.007). In a multivariate analysis, anterior tumor was the only independent risk factor for a positive CRM (odds ratio 4.725, 95% confidence interval 1.102-20.261, p = 0.037). In a morphometric analysis of 31 patients, the depth of tumor invasion from the muscularis mucosa was greater (11.9 mm vs. 6.6 mm, p = 0.028) in those with anterior tumors. CONCLUSION: Anterior tumors are associated with a higher risk of tumor-positive CRM and tend to exhibit deeper invasion in mid and low rectal cancer.

Impact of Resident-Performed Laparoscopic Appendectomy on Patient Outcomes and Safety.

BACKGROUND: Laparoscopic appendectomy is a training model for surgical residents to begin their surgical experience. However, there is concern about worse outcomes of surgery performed by inexperienced residents. We investigated surgical outcomes and patient safety in laparoscopic appendectomy performed by residents. MATERIALS AND METHODS: This is a retrospective cohort study of all consecutive patients operated on for acute appendicitis in a single tertiary hospital. A total of 971 patients who had laparoscopic appendectomy on an emergency basis between December 2010 and 2014 were analyzed. An attending, fellow, or resident with or without supervision performed the surgery. Surgical outcomes were compared among the four groups according to operator type. RESULTS: Laparoscopic appendectomy was successfully performed in 965 patients (99.4%) and was converted to open surgery in 6 patients. The conversion rate and incidence of complications were not different among the four groups. Operating time and length of hospital stay were significantly shorter in the attending group than in the fellow or resident groups, but did not differ between the fellow and resident groups. Unsupervised residents or fellows more often placed abdominal drainage than attending surgeons. Patients with drainage had a significantly longer hospital stay compared to patients without drainage (3.64 days versus 6.33 days, P ≤ .0001), as well as a longer mean time to gas passage (1.17 days versus 1.61 days, P ≤ .0001). CONCLUSIONS: Resident-performed laparoscopic appendectomy was safe, but was associated with significant prolongations in hospital stay and operation time. These differences were not clinically relevant with regard to complications.

Bidirectional alteration of Cav-1 expression is associated with mitogenic conversion of its function in gastric tumor progression.

BACKGROUND: Expression of caveolin-1 (Cav-1) is frequently altered in many human cancers and both tumor suppression and promotion functions of Cav-1 have been suggested based on its expression status. However, it remains unanswered how Cav-1 provokes opposite effects in different cancers or different phases of tumor progression. METHODS: To explore the implication of Cav-1 alteration in gastric tumorigenesis, the expression and mutational status of Cav-1 and its effects on tumor cell growth were characterized. RESULTS: A substantial fraction of primary tumors and cell lines displayed abnormally low or high Cav-1 mRNA expression, indicating the bidirectional alteration of Cav-1 in gastric cancers. While allelic imbalance and mutational alterations of the Cav-1 gene were rarely detected, aberrant promoter hyper- or hypo-methylation showed a tight correlation with bidirectional alteration of its expression. Abnormally low and high Cav-1 expression was more frequently observed in early and advanced cancers, respectively, suggesting the oncogenic switch of its function in tumor progression. Cell cycle progression, DNA synthesis, and colony forming ability were markedly decreased by Cav-1 transfection in low-expressing tumor cells but by its depletion in high-expressing cells. Interestingly, Cav-1 exerted opposite effects on MEK-ERK signaling in these two cell types through the reciprocal regulation of the RAF-ERK negative feedback loop. A feedback inhibition of RAF by ERK was stimulated by restoration of Cav-1 expression in low-expressing cells but by it depletion in high-expressing cells. As predicted, the opposite effects of Cav-1 on both tumor cell growth and inhibitory RAF phosphorylation were abolished if ERK is depleted. CONCLUSION: Bidirectional alteration of Cav-1 is linked to its opposite effects on gastric tumor cell growth, which stem from the reciprocal control on the RAF-ERK negative feedback loop.

Single-Port Laparoscopic Surgery Can Be Performed Safely and Appropriately for Colon Cancer: Short-Term Results of a Pilot Randomized Controlled Trial.

INTRODUCTION: Single-port laparoscopic surgery (SPLS) has gained popularity due to its cosmetic benefit, and therefore, has been applied to several kinds of benign operations, such as appendectomy and cholecystectomy. The safety and suitability of SPLS for colon cancer has not been widely proved. We aimed at validating the safety, efficacy, and short-term quality of life (QOL) of SPLS compared with conventional laparoscopic surgery (CLS) in patients with colon cancer. MATERIALS AND METHODS: Between June 2010 and April 2011, a total of 62 patients with pathology-proven colon cancer were randomly allocated to two groups: SPLS and CLS. Data were analyzed according to the intention-to-treat principle. RESULTS: In total, there were 62 patients (35 men and 27 women) with a mean age of 63.0 years (range, 38-82). The baseline characteristics of the patients and tumor factors were well balanced between two groups. The operation time and estimated blood loss were similar, whereas intraoperative complications only occurred in three patients, all of whom were in the SPLS group. Conversion to CLS or open surgery occurred in 6 (19.4%) patients of the SPLS group. The number of harvested lymph nodes and length of proximal and distal resection margins were not statistically different between two groups. Postoperative complications and recovery of bowel function were similar in both groups, but fatal postoperative complication occurred in one case in the SPLS group. The QOL between two groups was identical in all domains until postoperative 12 months. CONCLUSIONS: SPLS for colon cancer is feasible and can be performed by following oncologic principles. However, surgeons should be aware of the potential for unexpected adjacent organ injury ( ClinicalTrial.gov identifier: NCT01203969).

Learning curve for single-port laparoscopic colon cancer resection: a multicenter observational study.

BACKGROUND: The aim of this study was to investigate the learning curves (LCs) of single-port laparoscopic surgery (SPLS) for colon cancer using multidimensional statistical analyses. Although SPLS yields better cosmetic results and comparable short-term outcomes compared to conventional laparoscopic surgery, its technical difficulties make surgeons hesitant to try SPLS. Moreover, the LCs of SPLS for colon cancer are not well delineated. METHODS: Data were collected from patients who underwent SPLS for colon cancer in seven Korean institutions between May 2009 and May 2015. The LCs were analyzed using the moving average method and the cumulative sum control chart (CUSUM) for operation time and surgical failure. Surgical failure was defined as the any conversion, postoperative complications, or less than 12 harvested lymph nodes from surgical specimens. RESULTS: A total of 356 patients were included in this study. Six and three surgeons performed 282 anterior resections (ARs) and 74 right colectomies (RCs), respectively. On the basis of the moving average method and CUSUM for operation time and surgical failure, the LCs for AR were 18, 16, 35, 13, 36, and 13 cases for surgeons A-F, respectively. However, the LCs for RC were 6 and 15 cases for surgeons D and E, respectively, and were ambiguous for one surgeon. CONCLUSIONS: For surgeons experienced in conventional laparoscopic colorectal surgery, the LCs of SPLS for colon cancer ranged from 6 to 36 cases, which is shorter than the LCs reported for conventional laparoscopic surgery.