Risk Factor Analysis of Lymph Node Metastasis for Rectal Neuroendocrine Tumors: Who Needs a Radical Resection in Rectal Neuroendocrine Tumors Sized 1-2 cm?

BACKGROUND: Rectal neuroendocrine tumors (NETs) have malignant potential, and lymph node (LN) or distant metastases can occur; however, treatment of NETs 1-2 cm in size is controversial. OBJECTIVE: This study aimed to identify predictive factors for LN metastasis and prognostic factors for recurrence of rectal NETs, especially tumors 1‒2 cm in size. METHODS: Between October 2004 and November 2020, 453 patients underwent endoscopic or surgical treatment for rectal NETs in Seoul National University Hospital. The data on these patients were prospectively collected in our database and reviewed retrospectively. In cases of local excision, we evaluated LN metastasis with radiologic imaging, including computed tomography or magnetic resonance imaging before treatment and during the follow-up periods. RESULTS: LN metastasis was observed in 40 patients (8.8%). A higher rate of LN metastasis was observed in larger-sized tumors, advanced T stage, lymphovascular invasion (LVI), perineural invasion (PNI), and high tumor grade. In multivariable analysis, the significant risk factors for LN metastasis were tumor size (1 ≤ size < 2 cm: hazard ratio [HR] 64.07; size ≥2 cm: HR 102.37, p < 0.001) and tumor grade (G2: HR 3.63, p = 0.034; G3: HR 5.09, p = 0.044). In multivariable analysis for tumors 1-2 cm in size, the risk factor for LN metastasis was tumor grade (G2: HR 6.34, p = 0.013). CONCLUSIONS: Tumor grade and size are important predictive factors for LN metastasis. In NETs 2 cm in size, tumor grade is also important for LN metastasis, and radical resection should be considered.

Carbohydrate antigen 19-9 plus carcinoembryonic antigen for prognosis in colorectal cancer: An observational study.

AIM: Carcinoembryonic antigen (CEA) is a primary prognostic marker and can detect colorectal cancer (CRC) recurrence; however, it has low sensitivity. Carbohydrate antigen 19-9 (CA 19-9) can be used as a supplemental tumour marker along with CEA. The purpose of this study was to determine whether preoperative CA 19-9 added to CEA helped predict long-term prognosis and whether follow-up CA 19-9 added to CEA had additional benefits in diagnosing the recurrence of CRC. METHOD: We retrospectively assessed patients who underwent surgery for primary CRC between January 2004 and December 2015 at Seoul National University Hospital. Data on demographics, preoperative and follow-up CEA and CA 19-9 levels, recurrence and survival were obtained and analysed with respect to tumour marker levels to ascertain their prognostic and diagnostic values. RESULTS: A total of 4972 and 1530 patients were included to analyse preoperative and follow-up tumour marker levels, respectively. The 5-year relapse-free survival rates were 72.2% ± 0.8%, 52.5% ± 2.2%, 55.5% ± 3.2% and 32.1% ± 2.3% in the normal CEA and CA 19-9, high CEA, high CA 19-9, and high CEA and high CA 19-9 groups, respectively (all P < 0.001). Patients whose elevated CEA or CA 19-9 levels reduced to normal levels had better survival outcomes than those with postoperatively elevated levels. Elevated follow-up CA 19-9 and CEA levels were related to higher incidences of distant metastasis (CA 19-9, 14.0% vs. 23.1%, P = 0.004; CEA, 12.6% vs. 30.1%, P < 0.001) but not to local recurrence. Combined follow-up CEA and CA 19-9 increased the sensitivity for recurrence to 31.4%, with a 5% difference from the sensitivity of CEA alone. In the subgroup with high preoperative CA 19-9 levels, sensitivity increased by 18.2% overall. CONCLUSION: CA 19-9 is a valuable prognostic and diagnostic marker for CRC when used adjunctively with CEA and can be a supplementary marker with CEA to improve sensitivity, especially with elevated preoperative CA 19-9.

Safety of early surgery after self-expandable metallic stenting for obstructive left-sided colorectal cancer.

BACKGROUND: Self-expanding metallic stenting (SEMS) is usual for the temporary resolution of obstructive left-sided colorectal cancer (CRC) as a bridge to elective surgery. However, there is no consensus regarding adequate time intervals from stenting to radical surgery. The aim of this study was to identify the optimal time interval that results in favorable short- and long-term outcomes. METHODS: Data on patients with obstructive left-sided CRC who underwent elective radical surgery after clinically successful SEMS deployment in five tertiary referral hospitals from 2004 to 2016 were analyzed, retrospectively. An inverse probability treatment-weighted propensity score analysis was used to minimize bias. Postoperative short- and long-term outcomes were compared between two groups: an early surgery (within 8 days) group and delayed surgery (after 8 days) group. RESULTS: Of 311 patients, 148 (47.6%) underwent early and 163 (52.4%) underwent delayed surgery. The median surgery interval was 9.0 days. After adjustment, the groups had similar patient and tumor characteristics. In terms of short-term outcomes, there was no difference in hospitalization length or postoperative complications. No deaths were observed. With a median follow-up of 71.0 months, no significant difference was observed between the groups in 5-year overall survival (early vs. delayed surgery: 79.6% vs. 71.3%, P = 0.370) and 5-year disease-free survival (early vs. delayed surgery: 59.1% vs. 60.4%, P = 0.970). CONCLUSIONS: In obstructive left-sided CRC, the time interval between SEMS and radical surgery did not significantly influence short- and long-term outcomes. Therefore, early surgery after SEMS could be suggested if there is no reason to postpone surgery for preoperative medical optimization.

Oncologic safety of laparoscopic surgery after metallic stent insertion for obstructive left-sided colorectal cancer: a multicenter comparative study.

BACKGROUND: Self-expanding metallic stents (SEMSs) are used as a bridge to surgery in patients with obstructive colorectal cancer. However, the role of laparoscopic resection after successful stent deployment is not well established. We aimed to compare the oncologic outcomes of laparoscopic vs open surgery after successful colonic stent deployment in patients with obstructive left-sided colorectal cancer. METHODS: In this multicenter study, 179 (97 laparoscopy, 82 open surgery) patients with obstructive left-sided colorectal cancer who underwent radical resection with curative intent after successful stent deployment were retrospectively reviewed. To minimize bias, we used inverse probability treatment-weighted propensity score analysis. The short- and long-term outcomes between the groups were compared. RESULTS: Both groups had similar demographic and tumor characteristics. The operation time was longer, but the degree of blood loss was lower in the laparoscopy than in the open surgery group. There were nine (9.3%) open conversions. After adjustment, the groups showed similar patient and tumor characteristics. The 5-year disease-free survival (DFS) (laparoscopic vs open: 68.7% vs 48.5%, p = 0.230) and overall survival (OS) (laparoscopic vs open: 79.1% vs 69.0%, p = 0.200) estimates did not differ significantly across a median follow-up duration of 50.5 months. Advanced stage disease (DFS: hazard ratio [HR] 1.825, 95% confidence interval [CI]: 1.072-3.107; OS: HR 2.441, 95% CI 1.216-4.903) and post-operative chemotherapy omission (DFS: HR 2.529, 95% CI 1.481-4.319; OS: HR 2.666, 95% CI 1.370-5.191) were associated with relatively worse long-term outcomes. CONCLUSION: Stent insertion followed by laparoscopy with curative intent is safe and feasible; the addition of post-operative chemotherapy should be considered after successful treatment.

Upregulation of SLC2A3 gene and prognosis in colorectal carcinoma: analysis of TCGA data.

BACKGROUND: Upregulation of SLC2A genes that encode glucose transporter (GLUT) protein is associated with poor prognosis in many cancers. In colorectal cancer, studies reporting the association between overexpression of GLUT and poor clinical outcomes were flawed by small sample sizes or subjective interpretation of immunohistochemical staining. Here, we analyzed mRNA expressions in all 14 SLC2A genes and evaluated the association with prognosis in colorectal cancer using data from the Cancer Genome Atlas (TCGA) database. METHODS: In the present study, we analyzed the expression of SLC2A genes in colorectal cancer and their association with prognosis using data obtained from the TCGA for the discovery sample, and a dataset from the Gene Expression Omnibus for the validation sample. RESULTS: SLC2A3 was significantly associated with overall survival (OS) and disease-free survival (DFS) in both the discovery sample (345 patients) and validation sample (501 patients). High SLC2A3 expression resulted in shorter OS and DFS. In multivariate analyses, high SLC2A3 levels predicted unfavorable OS (adjusted HR 1.95, 95% CI 1.22-3.11; P = 0.005) and were associated with poor DFS (adjusted HR 1.85, 95% CI 1.10-3.12; P = 0.02). Similar results were found in the discovery set. CONCLUSION: Upregulation of the SLC2A3 genes is associated with decreased OS and DFS in colorectal cancer patients. Therefore, assessment of SLC2A3 gene expression may useful for predicting prognosis in these patients.

Ultimate Clinical Outcomes of Appendiceal Mucinous Neoplasm of Uncertain Malignant Potential.

BACKGROUND: The clinical outcome of appendiceal mucinous neoplasm (AMN) is not well understood. This study aimed to compare the long-term outcome for the uncertain malignant potential (UMP) subtype of AMNs with those of the mucinous adenoma (MA) and mucinous adenocarcinoma (MAC) subtypes. METHODS: In this study, AMNs were classified into three groups (MA, UMP, and MAC), and clinical characteristics, overall survival (OS), and progression-free survival (PFS) were compared among the three groups. RESULTS: The study included 65 AMN patients (26 MA, 20 UMP, and 19 MAC patients). The median follow-up period was 87 months (range 0.3-311.0) months. The symptoms at diagnosis and the presence of pseudomyxoma peritonei were more common in the MAC group than in the MA group (P = 0.012) or the UMP group (P < 0.001). The 5-year OS rates were 95.5% for the MA group, 93.8% for the UMP group, and 78.3% for the MAC group (P < 0.001), and the 5-year PFS rates were 95.2% for the MA group, 95% for the UMP group, and 36.8% for the MAC group (P < 0.001). Thus, OS and PFS did not differ significantly in the MA and UMP groups (P = 0.884 and 0.345, respectively). In contrast, the OS and PFS of the MAC group were worse than in the MA group (P = 0.017 and <0.001, respectively) or the UMP group (P < 0.001 and 0.001, respectively). CONCLUSIONS: The long-term outcome for UMP tumors is similar to that for MA tumors and significantly better than for MAC tumors.

Does routine colonoscopy help diagnose familial adenomatous polyposis in patients presenting with desmoid tumors but no gastrointestinal symptoms?

PURPOSE: Desmoid tumor (DT) is a rare myofibroblastic proliferative neoplasm, but can occur in up to 26% of patients with familial adenomatous polyposis (FAP). Therefore, DT may be an extraintestinal manifestation of FAP that precedes the development of advanced malignancies. The aim of this study was to identify the incidence of polyps in DT patients and investigate value of colonoscopy for diagnosis of FAP in DT patients without gastrointestinal symptoms. MATERIALS AND METHODS: The records of patients diagnosed with DT were retrospectively reviewed using the clinical data warehouse (CDW) system. Clinical data, including location of tumor, type(s) of treatment, and colonoscopic findings, were collected. RESULTS: Sixty-five patients were diagnosed with DT during the study period; 10 patients received colonoscopies before diagnosis of DT, and 20 patients received colonoscopies after diagnosis of DT. The mean age at diagnosis of DT was 41.9 ± 16.7 years old (range 17-74). Most tumors were extra-abdominal (n = 24, 80.0%), and fewer were intra-abdominal (n = 4, 13.3%) or in an abdominal wall (n = 2, 6.7%). The colonoscopy results revealed one or two tubular adenomas in 11 patients (36.6%), although none of the patients had colorectal polyposis or colorectal cancer. CONCLUSION: None of the patients in our study population had colorectal polyposis. Routine colonoscopy of DT patients without gastrointestinal symptoms seems to have low diagnostic yield for detection of FAP.

Initial experience of transanal total mesorectal excision with rigid or flexible transanal platforms in cadavers.

BACKGROUND: Transanal total mesorectal excision (taTME) is expected to provide benefits in the removal of the complete mesorectum for low rectal lesions, and several clinical studies regarding this technique have been reported. However, a transanal platform has not yet been standardized, and diverse transanal endoluminal surgery access devices have been used, based on individual surgeon preferences. In the present study, we performed laparoscopy-assisted taTME in cadavers and compared the characteristics of four different platforms. METHODS: Between January 2013 and April 2015, laparoscopy-assisted taTME was performed on six fresh cadavers. Flexible [SILS™ Port (Covidien), GelPOINT(®) Path Transanal Access Platform (Applied Medical)] and rigid [TEO(®) (Karl Storz Endoskope), TEM (Richard Wolf)] transanal access platforms were used on three cadavers each. RESULTS: All cadavers were male, with a mean age of 69.2 (range 57-86) years. The mean operation time was 146.3 (range 140-155) min with flexible platforms and 206.7 (range 150-260) min with rigid platforms. The mean specimen length was 23 (range 18-26) cm. Complete or nearly complete mesorectal specimens were obtained in all cases, except for one case using the TEM platform. Flexible platforms (SILS and GelPOINT) provided a short set-up time, relatively atraumatic retraction, and easy application of familiar laparoscopic instruments; a narrow operative field was its limitation. The rigid platforms (TEO and TEM) enabled larger and more stable operative fields and space than did the SILS platform, but they were limited by a narrow view, prolonged set-up time, rigidity, and long channels relative to the short distance from the anus to the rectal closure site. CONCLUSION: In this preliminary study, laparoscopy-assisted taTME was a feasible and safe procedure using both rigid and soft platforms, despite some limitations of each platform.

Three-dimensional body composition parameters using automatic volumetric segmentation allow accurate prediction of colorectal cancer outcomes.

BACKGROUND: Parameters obtained from two-dimensional (2D) cross-sectional images have been used to determine body composition. However, data from three-dimensional (3D) volumetric body images reflect real body composition more accurately and may be better predictors of patient outcomes in cancer. This study aimed to assess the 3D parameters and determine the best predictive factors for patient prognosis. METHODS: Patients who underwent surgery for colorectal cancer (CRC) between 2010 and 2016 were included in this study. Preoperative computed tomography images were analysed using an automatic segmentation program. Body composition parameters for muscle, muscle adiposity, subcutaneous fat (SF) and abdominal visceral fat (AVF) were assessed using 2D images at the third lumbar (L3) level and 3D images of the abdominal waist (L1-L5). The cut-off points for each parameter were determined using X-tile software. A Cox proportional hazards regression model was used to identify the association between the parameters and the treatment outcomes, and the relative influence of each parameter was compared using a gradient boosting model. RESULTS: Overall, 499 patients were included in the study. At a median follow-up of 59 months, higher 3D parameters of the abdominal muscles and SF from the abdominal waist were found to be associated with longer overall survival (OS) and disease-free survival (all P < 0.001). Although the 3D parameters of AVF were not related to survival outcomes, patients with a high AVF volume and mass experienced higher rate of postoperative complications than those with low AVF volume (27.4% vs. 18.7%, P = 0.021, for mass; 27.1% vs. 19.0%, P = 0.028, for volume). Low muscle mass and volume (hazard ratio [HR] 1.959, P = 0.016; HR 2.093, P = 0.036, respectively) and low SF mass and volume (HR 1.968, P = 0.008; HR 2.561, P = 0.003, respectively), both in the abdominal waist, were identified as independent prognostic factors for worse OS. Along with muscle mass and volume, SF mass and volume in the abdominal waist were negatively correlated with mortality (all P < 0.001). Both AVF mass and volume in the abdominal waist were positively correlated with postoperative complications (P < 0.05); 3D muscle volume and SF at the abdominal waist were the most influential factors for OS. CONCLUSIONS: 3D volumetric parameters generated using an automatic segmentation program showed higher correlations with the short- and long-term outcomes of patients with CRC than conventional 2D parameters.

A 3 mm Port Reduces Postoperative Pain After Laparoscopic Colon Cancer Surgery: A Case-control Matched Study.

BACKGROUND: Recently, smaller-size trocars and instruments have been developed for laparoscopic colon cancer surgery; however, their effectiveness and safety have not been elucidated. This study aimed to investigate whether 3 mm trocars and instruments have benefits compared with conventional trocars and instruments. PATIENTS AND METHODS: Patients with colon cancer who underwent laparoscopic anterior resection or right hemicolectomy were included. Patients who underwent combined resections of other organs and those with conversion to open surgery were excluded. In the 3 mm group, three 5 mm trocars were replaced by 3 mm trocars. The numeric rating scale (NRS) immediately postoperatively at 24, 48, and 72 hours, respectively, after surgery and the use of additional analgesics and perioperative outcomes were analyzed. Case-control matched analysis was used to reduce bias according to the type of surgery. RESULTS: A total of 207 patients (conventional: n = 158, 3 mm: n = 49) were included. Before matching, NRS 48 hours postoperatively ( P = 0.049), proportion of patients using additional intravenous (IV) analgesics ( P = 0.007), postoperative hospital stay ( P < 0.001), and blood loss ( P < 0.001) were lower in the 3 mm group. In multivariable analysis, trocar type significantly impacted the proportion of patients using additional IV analgesics (odds ratio: 0.330; 95% CI: 0.153-0.712; P = 0.005). After case-control matching, NRS immediately postoperatively ( P = 0.015) and 24 hours postsurgery ( P = 0.043), patients using additional IV analgesics ( P = 0.019), postoperative hospital stay ( P = 0.010), intraoperative blood loss ( P < 0.001), and postoperative complication rate ( P = 0.028) were significantly lower in the 3 mm group compared with the 5 mm group. CONCLUSIONS: The use of 3 mm trocars and instruments in laparoscopic colon cancer surgery can effectively reduce postoperative pain while maintaining perioperative safety.

Depth of mesorectal extension has prognostic significance in patients with T3 rectal cancer.

BACKGROUND: More than half of all rectal cancers are T3 lesions, but they are classified as a single-stage category. OBJECTIVE: The aim of this study was to validate prognostic significance of mesorectal extension depth in T3 rectal cancer. DESIGN: This study is a retrospective analysis of oncologic outcomes of patients with T3 rectal cancer grouped by mesorectal extension depth (T3a, <1 mm; T3b, 1-5 mm; T3c, 5-15 mm; T3d, >15 mm). SETTINGS: This study was conducted at a tertiary referral cancer hospital. PATIENTS: From 2003 to 2009, 291 patients who underwent a curative surgery were included. MAIN OUTCOME MEASURES: Oncologic outcomes in terms of disease-free survival were analyzed. RESULTS: The 5-year disease-free survival rate according to T3 subclassification was 86.5% for T3a, 74.2% for T3b, 58.3% for T3c, and 29.0% for T3d. It was significantly higher in T3a,b tumors than that in T3c,d tumors (77.6% vs 55.2%, p < 0.001). On univariate and multivariate analysis, prognostic factors affecting recurrence were preoperative CEA level ≥ 5 ng/mL (HR 2.617, 95% CI 1.620-4.226), lymph node metastasis (HR 3.347, 95% CI 1.834-6.566), and mesorectal extension depth >5 mm (HR 1.661, 95% CI 1.013-2.725). In subgroup analysis, independent prognostic factors were preoperative CEA level and mesorectal extension depth >5 mm for 200 patients with ypT3 rectal cancer and preoperative CEA level and lymph node metastasis for 91 patients with pT3 rectal cancer. LIMITATIONS: This study lacks quality of surgery plane evaluation because of its retrospective nature. Moreover, pathologic examination was not done with a whole-mount section. CONCLUSIONS: Depth of mesorectal extension >5 mm is a significant prognostic factor in patients with T3 rectal cancer. Depth of mesorectal extension especially may be more important than the nodal status in predicting the oncologic outcome for patients who had received preoperative chemoradiotherapy.

Surgical treatment of complicated right colonic diverticulitis: laparoscopic versus open surgery.

BACKGROUND: Complicated right colonic diverticulitis is more common in Eastern countries. Although this disease entity is treated primarily with surgery, it is uncertain whether the outcomes of laparoscopic treatment also are comparable with those of open surgery. This study aimed to evaluate the outcome for laparoscopic surgical management of complicated right-sided colonic diverticulitis compared with that for open surgery. METHODS: Between 1999 and 2011, 59 patients who underwent extensive surgery for complicated right colonic diverticulitis were enrolled from two hospitals. All the patients were suspected of having a large abscess or perforation with peritonitis symptoms preoperatively. Laparoscopic surgery was performed for 28 consecutive patients in the one hospital, and open surgery was performed for 31 consecutive patients in the other hospital. There was no conversion in the laparoscopic surgery cases. Clinical outcomes were analyzed and compared between the two groups. RESULTS: Laparoscopic surgery had a longer operating time (165 min) than open surgery (132 min) (p = 0.003). The two groups did not differ significantly in terms of postoperative hospital stay (laparoscopy 9.8 ± 2.7 days versus open surgery 12.8 ± 8.8 days; p = 0.234) or resumption of diet (laparoscopy 5.5 ± 2.4 days versus open surgery 6.3 ± 3.0 days; p = 0.286). Five patients in the laparoscopy group (17.8 %) had complications such as ileus, abscess, and bleeding, one of whom was treated with surgery. Nine patients in the open surgery group (29 %) had complications, two of whom were treated with surgery. CONCLUSIONS: The laparoscopic approach to complicated right colonic diverticulitis may be feasible. The clinical outcomes were comparable with those for open surgery.

Investigation of the clinical features and recurrence patterns of acute right-sided colonic diverticulitis: A retrospective cohort study.

Background: Right-sided colonic diverticulitis (RCD) and left-sided colonic diverticulitis (LCD) are considered distinct diseases. However, separate guidelines for RCD do not exist. Since the establishment of RCD management would first require evaluation of disease characteristics and recurrence patterns, this study has aimed to investigate the differences in the clinical characteristics between RCD and LCD and the recurrence patterns of RCD. Methods: Patients admitted for colonic diverticulitis between January 2012 and August 2020 were retrospectively reviewed. Clinical characteristics and recurrence rates in RCD and LCD patients, and predictors for recurrence and the recurrence patterns of RCD were analyzed. Results: In total, 446 colonic diverticulitis patients (343 RCD, 103 LCD) were included in this study. RCD patients were more likely to be male, younger, taller, heavier, smoke, drink alcohol, have better physical performance scores, lower modified Hinchey stages and better initial laboratory findings. LCD patients were more likely to receive invasive treatments, have longer fasting and hospital days, higher mortality and cumulative recurrence rates (20.5% vs. 30.4%, P = 0.007). Recurrences in most RCD patients were of similar disease severity and received the same treatments for initial attacks, with rates of recurrence increasing after each recurrence. Predictors of the recurrence of RCD were complicated diverticulitis (hazard ratio[HR] 2.512, 95% confidence interval[CI] 0.127-5.599, p = 0.024) and percutaneous drainage (HR 6.549, 95% CI 1.535-27.930, p = 0.011). Conclusion: RCD is less severe and has a lower recurrence rate than LCD, suggesting that RCD should be treated conservatively. Patients with complicated diseases and those requiring percutaneous drainage are more likely to experience a disease recurrence, suggesting nonsurgical management may be insufficient.

The impact of heavy smoking on anastomotic leakage and stricture after low anterior resection in rectal cancer patients.

BACKGROUND: Anastomotic complications after low anterior resection are associated with perianastomotic ischemia. Smoking is one of the main causes of microvascular disease that is correlated with tissue ischemia. The purpose of the present study was to assess the impact of smoking on anastomotic complications after low anterior resection in rectal cancer patients. METHODS: Between January 2005 and December 2008, 412 patients underwent low anterior resection for rectal cancers by a single surgeon at Seoul National University Hospital. Excluded from this series were 197 patients with postoperative radiation therapy, cancers that were located above 10 cm from the anal verge, or lack of medical records, and the remaining 215 patients were included for analysis. Significant variables in the univariate analysis were subsequently subject to multivariate analysis for identification of risk factors for complications. RESULTS: The rate of anastomotic complications was 10.7% (23 of 215 patients). Univariate analysis showed that male gender, body mass index higher than 25 kg/m(2), smoking history, smoking amount, type of operation, and presence of a protective stoma were associated with anastomotic complications. In multivariate analysis, a history of heavy smoking was a significant risk factor for anastomotic complications. CONCLUSIONS: A history of heavy smoking (more than 40 pack-years) is an independently significant risk factor for anastomotic complications after low anterior resection in rectal cancer patients.

Interleukin 10 level in the peritoneal cavity is a prognostic marker for peritoneal recurrence of T4 colorectal cancer.

Peritoneal recurrence (PR) is a major relapse pattern of colorectal cancer (CRC). We investigated whether peritoneal immune cytokines can predict PR. Cytokine concentrations of peritoneal fluid from CRC patients were measured. Patients were grouped according to peritoneal cancer burden (PCB): no tumor cells (≤ pT3), microscopic tumor cells (pT4), or gross tumors (M1c). Cytokine concentrations were compared among the three groups and the associations of those in pT4 patients with and without postoperative PR were assessed. Of the ten cytokines assayed, IL6, IL10, and TGFB1 increased with progression of PCB. Among these, IL10 was a marker of PR in pT4 (N = 61) patients based on ROC curve (p = 0.004). The IL10 cut-off value (14 pg/mL) divided patients into groups with a low (7%, 2 of 29 patients) or high (45%, 16 of 32 patients) 5-year PR (p < 0.001). Multivariable analysis identified high IL10 levels as the independent risk factor for PR. Separation of patients into training and test sets to evaluate the performance of IL10 cut-off model validated this cytokine as a risk factor for PR. Peritoneal IL10 is a prognostic marker of PR in pT4 CRC. Further research is necessary to identify immune response of intraperitoneal CRC growth.

Guidelines for accreditation of endoscopy units: quality measures from the Korean Society of Coloproctology.

PURPOSE: Colonoscopy is an effective method of screening for colorectal cancer (CRC), and it can prevent CRC by detection and removal of precancerous lesions. The most important considerations when performing colonoscopy screening are the safety and satisfaction of the patient and the diagnostic accuracy. Accordingly, the Korean Society of Coloproctology (KSCP) herein proposes an optimal level of standard performance to be used in endoscopy units and by individual colonoscopists for screening colonoscopy. These guidelines establish specific criteria for assessment of safety and quality in screening colonoscopy. METHODS: The Colonoscopy Committee of the KSCP commissioned this Position Statement. Expert gastrointestinal surgeons representing the KSCP reviewed the published evidence to identify acceptable quality indicators and indicators that lacked sufficient evidence. RESULTS: The KSCP recommends an optimal standard list for quality control of screening colonoscopy in the following 6 categories: training and competency of the colonoscopist, procedural quality, facilities and equipment, performance indicators and auditable outcomes, disinfection of equipment, and sedation and recovery of the patient. CONCLUSION: The KSCP recommends that endoscopy units performing CRC screening evaluate 6 key performance measures during daily practice.

Quality of life after sphincter preservation surgery or abdominoperineal resection for low rectal cancer (ASPIRE): A long-term prospective, multicentre, cohort study.

BACKGROUND: The long-term effects of radical resection on quality of life may influence the treatment selection. The objective of this study was to determine whether abdominoperineal resection has a better effect on the quality of life than sphincter preservation surgery at 3 years after surgery. METHODS: This prospective, cohort study included patients who underwent radical resection for low rectal cancer. The primary outcomes were European Organisation for Research and Treatment of Cancer QLQ-C30 and CR38 quality of life scores 3 years after surgery, which were compared with linear generalised estimating equations, after adjustment for baseline values, a time effect, and an interaction effect between time and treatment. The secondary outcomes included sexual-urinary functions and oncological outcomes. The study was registered with ClinicalTrials.gov (NCT01461525). FINDINGS: Between December 2011 and August 2016, 342 patients were enrolled: 268 (78•4%) underwent sphincter preservation surgery and 74 (21•6%) underwent abdominoperineal resection. The global quality of life scores did not differ between sphincter preservation surgery and abdominoperineal resection groups (adjusted mean difference, 4•2 points on a 100-point scale; 95% confidence interval  [CI], -1•3 to 9•7, p = 0•1316). Abdominoperineal resection was associated with a worse body image (9•8 points; 95% CI, 2•9 to 16•6, p = 0•0052), micturition symptoms (-8•0 points; 95% CI, -14•1 to -1•8, p = 0•0108), male sexual problems (-19•9 points; 95% CI, -33•1 to -6•7, p = 0•0032), less confidence in getting and maintaining an erection in males (0•5 points on a 5-point scale; 95% CI, 0•1 to 0•8, p = 0•0155), and worse urinary symptoms (-5•4 points on a 35-point scale; 95% CI, -8•0 to -2•7, p < 0•0001). The 5-year overall survival was worse with abdominoperineal resection in unadjusted (92•2% vs 80•9%; difference 11•3%, hazard ratio 2•38; 95% CI, 1•27 to 4•46, p = 0•0052), but did not differ after adjustment. INTERPRETATION: In this long-term prospective study, abdominoperineal resection failed to meet the superiority to sphincter preservation surgery in terms of quality of life. Although the global quality of life scores did not differ between groups, this study suggests that sphincter preservation surgery can be an acceptable alternative to abdominoperineal resection for low rectal cancer, offering a better quality of life and sexual-urinary functions, with no increased oncological risk even after 3 years. FUNDING: Seoul National University Bundang Hospital, Korea.

Feasibility and Advantages of Transanal Minimally Invasive Surgery (TAMIS) for Various Lesions in the Rectum.

Purpose: We report our experience in the use of transanal minimally invasive surgery (TAMIS) and the feasibility and safety of this surgical technique in operating for various rectal diseases that require a transanal approach. Methods: Between 2013 and 2019, 30 patients underwent TAMIS for a rectal lesion at Seoul National University Boramae Medical Center. The clinical data including age, gender, body mass index, tumour size, distance from the anal verge, diagnosis, operation time, postoperative complications, duration of hospital stay, and post-operative margin status were obtained retrospectively from the electronic medical records. Results: The mean operation time was 52.1±33.5 and the mean duration of hospital stay after surgery was 4.3±4.2 days. Most of the patients had undergone TAMIS for neuroendocrine tumor (NET) (60%) followed by an adenoma (16.7%) and rectal cancer (13.3%). 4 patients (13.3%) had minor complications after TAMIS. 2 patients (50%) had complained of diarrhea, 1 patient (25%) complained of fecal incontinence and 1 patient (25%) been diagnosed fluid in the operation bed. Conclusion: TAMIS is a useful method for local excision of rectal lesion located in mid to upper rectum as well as other rectal pathologies that require a transanal approach.

Risk factors of elderly patients with postoperative delirium following major abdominal surgery for cancer.

Purpose: Postoperative delirium (POD) is a common complication in elderly patients after major abdominal surgery for cancer. Although POD is related with a poor outcome, there have not been many reports about POD after abdominal surgery in Korea. The aims of study were to analyze the characteristics and surgical outcomes of elderly patients with POD and to identify the risk factors of POD. Methods: From November 2016 to January 2019, we prospectively enrolled 63 patients who were aged ≥75 years and underwent major abdominal surgery for cancer. POD was daily assessed for up to 10 days postoperatively with the Confusion Assessment Method and a validated chart review. Results: POD occurred in eight patients (12.7%). Univariate analysis showed that the occurrence of POD was related to sodium <135 mEq/L (P=0.037), combined resection (P=0.023), longer surgery/anesthesia time (P=0.023 and P=0.037, respectively), increased blood loss (P=0.004), postoperative admission to intensive care unit (ICU) (P=0.023), and duration of Foley catheter (P=0.011), however, multivariate analysis identified no significant risk factors of POD. There was no difference in postoperative outcomes such as hospital stay, mortality, reoperation, and morbidity between patients with POD and without POD. Conclusion: Elderly patients with hyponatremia, combined resection, longer operation/anesthesia time and admission to ICU had tendencies to develop POD after major abdominal surgery. Surgeons should pay more attention to prevent POD, and a large-scale prospective study is needed to identify the risk factors of POD.

Surgical Management of Sigmoid Volvulus: A Multicenter Observational Study.

PURPOSE: This study aimed to evaluate real-world clinical outcomes from surgically treated patients for sigmoid volvulus. METHODS: Five tertiary centers participated in this retrospective study with data collected from October 2003 through September 2018, including demographic information, preoperative clinical data, and information on laparoscopic/open and elective/emergency procedures. Outcome measurements included operation time, postoperative hospitalization, and postoperative morbidity. RESULTS: Among 74 patients, sigmoidectomy was the most common procedure (n = 46), followed by Hartmann's procedure (n = 23), and subtotal colectomy (n = 5). Emergency surgery was performed in 35 cases (47.3%). Of the 35 emergency patients, 34 cases (97.1%) underwent open surgery, and a stoma was established for 26 patients (74.3%). Elective surgery was performed in 39 cases (52.7%), including 21 open procedures (53.8%), and 18 laparoscopic surgeries (46.2%). Median laparoscopic operation time was 180 minutes, while median open surgery time was 130 minutes (P < 0.001). Median postoperative hospitalization was 11 days for laparoscopy and 12 days for open surgery. There were 20 postoperative complications (27.0%), and all were resolved with conservative management. Emergency surgery cases had a higher complication rate than elective surgery cases (40.0% vs. 15.4%, P = 0.034). CONCLUSION: Relative to elective surgery, emergency surgery had a higher rate of postoperative complications, open surgery, and stoma formation. As such, elective laparoscopic surgery after successful sigmoidoscopic decompression may be the optimal clinical option.