Technical risk factors for benign anastomotic strictures in colorectal and/or coloanal anastomosis: A retrospective case-control study.

AIM: Anastomotic stricture occurs in up to 30% of colorectal resections; however, evidence on risk factors and preventive measures remains scarce. This study aimed to identify technical factors responsible for increasing the risk for colorectal and coloanal anastomotic strictures. METHOD: This was a retrospective cohort study of patients with anastomotic stricture who underwent resection and/or redo anastomosis between January 1, 2011 and August 1, 2021 in a tertiary referral centre. Patients with anastomotic stricture were compared with an equal number of randomly selected patients without anastomotic complications, who were operated on during the same time period. The main outcome measures were technical risk factors of anastomotic stricture. RESULTS: Each group included 50 patients who were similar for age, sex, American Society of Anesthesiologists score, distance of anastomosis to the dentate line and indication for surgery. Median follow-up was significantly longer in the non-stricture group (38.6 months vs. 12.6 months, p = 0.04). Splenic flexure mobilization [hazard ratio (HR) = 0.18 [2], 95% CI: 0.08-0.39, p < 0.001], high ligation of the inferior mesenteric artery (HR = 0.22, 95% CI: 0.09-0.5, p < 0.001) and high ligation of the inferior mesenteric vein (HR = 0.21, 95% CI: 0.09-0.50, p < 0.001) were associated with a lower likelihood of anastomotic stricture. Conversely, use of a 25-mm-diameter circular stapler (HR = 22.69, 95% CI: 2.69-191.10, p < 0.001), clinically significant anastomotic leak (HR = 3.94, 95% CI: 2.04-7.64, p < 0.001), firing the stapler more than once for rectal division (HR = 24.75, 95% CI: 6.85-89.38, p < 0.001) and diverting stoma (HR = 3.087, 95% CI: 1.736-5.491, p < 0.0001) were predictive of an anastomotic stricture. CONCLUSION: Failure to mobilize the splenic flexure and to perform high ligation of the inferior mesenteric vessels were associated with higher odds of anastomotic stricture. A small-diameter circular stapler and multiple distal stapler firings were also associated with anastomotic stricture. These data support routine splenic flexure ligation and high ligation of the inferior mesenteric vessels as well as avoidance of both multiple  stapler firings for rectal transection and a 25-mm circular stapler for anastomosis..

Heterogeneity in survival within age groups of early-onset colorectal cancer patients: A National Cancer Database analysis.

BACKGROUND: We aimed to identify predictors of and heterogeneity in survival among different age groups of patients with early-onset colorectal cancer (EOCRC). METHODS: This retrospective cohort study used National Cancer Database data from 2004 to 2019. Differences in survival among CRC patients <50 years, subcategorized into age groups (<20, 20-29, 30-39, 40-49 years) were compared for demographic, clinical, and histologic features by univariate and multivariate analyses. Cox hazard regression and Kaplan Meier survival analysis were performed. RESULTS: 134 219 of the 1 240 787 individuals with CRC (10.8%) were <50 years old; 46 639 (34.8%) had rectal and 87 580 (65.3%) had colon cancer. Within the colon cancer cohort, individuals aged between 30 and 39 years had the highest overall survival rate (66.7%) during a median follow-up of 47.6 months (interquartile range IQR 23.1-89.7). The same age group in the rectal cancer cohort had the lowest survival rate (31%) over a median follow-up of 54.5 (IQR 28.24-97.31) months. Leading factors affecting survival included tumor stage (HR 8.23 [4.64-14.6]; p < 0.0001), lymphovascular invasion (HR 1.88 [1.70-2.06]; p < 0.0001) and perineural invasion (HR 1.08 [1.02-1.15]; p = 0.001). CONCLUSION: Survival trends vary within age groups of patients affected with early onset colon cancer compared to rectal cancer. Tumor stage and unfavorable pathological characteristics are the strongest factors predicting survival.

Factors Associated With Prolonged Operative Times in Laparoscopic Right Hemicolectomy and Its Association With Short-Term Outcomes.

BACKGROUND: This study aimed to investigate factors associated with prolonged operative time in laparoscopic right hemicolectomy for colon cancer. METHODS: This was a retrospective review of patients with colon cancer who underwent laparoscopic right hemicolectomy between 2011 and 2021. Linear and binary logistic regression analyses were performed to determine factors associated with prolonged operative time. The association between longer operative times and complications and hospital stay was assessed. RESULTS: One hundred and ninety-seven patients (52.3% female; mean age: 68.8 ± 14.1 years) were included. Factors independently associated with operative time were male sex (ß = 17.3, 95% CI: 2, 32.5; p = 0.026) and extended hemicolectomy (ß = 67.7, 95% CI: 27.6, 107.9; p = 0.001). American Society of Anesthesiologists (ASA) IV classification had a borderline significant association with operative time (ß = 100.4, 95% CI: -2.05, 202.9; p = 0.055). Male sex (r = 0.158; p = 0.026), body mass index (r = 0.205; p = 0.004), ASA classification (r = 0.232; p = 0.001), extended hemicolectomy (r = 0.256; p < 0.001), and intracorporeal vessel control (r = 0.161; p = 0.025) had significant positive correlation with operative times. Patients with operative times ≥ 160 min had significantly longer hospital stays (5 vs. 4 days; p = 0.043) and similar complication rates to patients with shorter operative times. CONCLUSIONS: Male sex, advanced ASA classification, and extended hemicolectomy were independently and significantly associated with longer operative times in laparoscopic right hemicolectomy. Longer operative times were associated with longer hospital stays and similar complication rates.

The impact of facility type on surgical outcomes in colon cancer patients: analysis of the national cancer database.

BACKGROUND: The type of facility where patients with colon cancer are treated may play a significant role in their outcomes. We aimed to investigate the influence of facility types included in the National Cancer Database (NCDB) on surgical outcomes of colon cancer. METHODS: Retrospective cohort analysis of all patients with stage I-III colon cancer included in the NCDB database between 2010 and 2019 was performed. Patients were grouped based on facility type: Academic/Research Programs (ARP), Community Cancer Programs (CCP), Comprehensive Community Cancer Programs (CCCP), and Integrated Network Cancer Programs (INCP). Study outcomes included overall survival, 30- and 90-day mortality, 30-day readmission and conversion to open surgery. RESULTS: 125,935 patients were included with a median age of 68.7 years (50.5% females). Most tumors were in the right colon (50.6%). Patient were distributed among facility types as ARP (n = 34,321, 27%), CCP (n = 12,692, 10%), CCCP (n = 54,356, 43%), and INCP (n = 24,566, 19%). In terms of surgical approach, laparoscopy was more commonly used in ARP (46%) (p < 0.001). Laparotomy was more common in CCP (58.7%) (p < 0.001), and conversely, CCP had the least amount of robotic surgery (3.9%) (p < 0.001). Median overall survival was highest in ARP (129 months, 95% CI 127.4-134.1) and lowest in CCP (103.7 months, 95% CI 100.1-106.7) (p < 0.001). Conversion rates were comparable between ARP (12%), CCCP (12%) and INCP (11.8%) but were higher in CCP (15.5%) (p < 0.001). 30-day readmission rates and 30-day mortality rates were significantly lower in ARP compared to other facility types (p < 0.001). CONCLUSION: Our findings display differences in surgical outcomes of colon cancer patients among facility types. The findings suggest better outcomes in terms of operative access and survival at ARP as compared to other facilities. These findings underscore the importance of understanding facility-specific factors that may influence patient outcomes and can guide resource allocation and targeted interventions for improving colon cancer care.

Predictors and outcomes of delays between diagnosis and definitive surgery for rectal cancer.

BACKGROUND: The National Accreditation Program for Rectal Cancer (NAPRC) recommends definitive treatment of rectal cancer commence within 60 days from diagnosis. This study aimed to assess predictors of >60 days delay between diagnosis and definitive surgery of rectal cancer and the impact on survival and short-term outcomes. METHODS: Retrospective cohort analysis of patients with stage I-III rectal adenocarcinoma who underwent proctectomy without preoperative neoadjuvant treatment from the National Cancer Database (2015-2019). Based on the time interval between diagnosis and definitive surgery, patients were divided into timely non-adherent (>60 days) and timely-adherent (≤60 days) groups. Multivariate analysis determined predictors of delayed definitive surgery. RESULTS: 9479 patients (57.5 % males; mean age: 63.7 years) had a 41-day median time between diagnosis and definitive surgery. Non-adherence was noted in 27.9 % of patients. Independent predictors of non-adherence were male sex (Odds ratio [OR]: 1.25; p < 0.001), Black (OR: 1.65; p < 0.001) or Asian (OR: 1.33; p = 0.014) race, Charlson score 2 (OR: 1.33; p = 0.005) or 3 (OR: 1.55; p < 0.001), urban residence (OR: 1.21; p = 0.003), abdominoperineal resection (OR: 1.69; p < 0.001), pelvic exenteration (OR: 1.7; p = 0.002), and robotic-assisted surgery (OR: 1.22; p = 0.001). Medicare (OR: 0.725; p = 0.003) and private insurance (OR: 0.711; p < 0.001) were associated with better adherence. 30-day and 90-day mortality, unplanned readmission, and overall survival were similar. CONCLUSIONS: Male Black or Asian patients with high Charlson scores, and undergoing abdominoperineal resection, pelvic exenteration, and robotic-assisted surgery were more likely non-adherent with NAPRC standards with >60 days delay before definitive surgery for rectal cancer. Hopefully, recognition for these reasons for delay of definitive surgery will lead to an improvement in adherence to the standards.

Pathologic Outcomes and Survival in Patients with Rectal Cancer and Increased Body Mass Index.

INTRODUCTION: We assessed the association between increased body mass index (BMI) and rectal cancer outcomes. METHODS: We included patients who underwent surgery for stage I-III rectal adenocarcinoma who were divided according to BMI at diagnosis: ideal BMI (18.5-24.9 kg/m2) and increased BMI (≥25 kg/m2). Groups were compared using univariate association analyses relative to baseline characteristics, pathologic outcomes, overall survival (OS), and disease-free survival (DFS). Main outcome measures involved circumferential resection margin (CRM), pathologic TNM stage, total mesorectal incision (TME) grade, OS, and DFS. RESULTS: 243 patients (64.6% male; median age 59 years) with a median BMI of 26.3 kg/m2 were included. 62.1% had BMI ≥25 kg/m2. Increased BMI patients had similar proportions of males (66.9% vs. 60.9%; p = 0.407) and comorbidities (ASA III: 47% vs. 37.4%; p = 0.24) to ideal BMI patients. There were no significant differences in cN1-2 stage (p = 0.279) or positive CRM (p = 0.062) rates. The groups had similar complete/near-complete TME, pathologic TN stage, and survival rates. Pathologic and survival outcomes were also similar with a BMI cutoff of 30. CONCLUSIONS: There was a trend toward more nodal involvement in preoperative assessment and less CRM involvement in the final pathology of patients with increased BMI. Complete/near-complete TME and survival rates were comparable between the groups.

Umbrella review of systematic reviews on the efficacy and safety of using mesh in the prevention of parastomal hernias.

BACKGROUND: This umbrella review aimed to summarize the findings and conclusions of published systematic reviews on the prophylactic role of mesh against parastomal hernias in colorectal surgery. METHODS: PRISMA-compliant umbrella overview of systematic reviews on the role of mesh in prevention of parastomal hernias was conducted. PubMed and Scopus were searched through November 2023. Main outcomes were efficacy and safety of mesh. Efficacy was assessed by the rates of clinically and radiologically detected hernias and the need for surgical repair, while safety was assessed by the rates of overall complications. RESULTS: 19 systematic reviews were assessed; 7 included only patients with end colostomy and 12 included patients with either ileostomy or colostomy. The use of mesh significantly reduced the risk of clinically detected parastomal hernias in all reviews except one. Seven reviews reported a significantly lower risk of radiologically detected parastomal hernias with the use of mesh. The pooled hazards ratio of clinically detected and radiologically detected parastomal hernias was 0.33 (95%CI: 0.26-0.41) and 0.55 (95%CI: 0.45-0.68), respectively. Six reviews reported a significant reduction in the need for surgical repair when a mesh was used whereas six reviews found a similar need for hernia repair. The pooled hazards ratio for surgical hernia repair was 0.46 (95%CI: 0.35-0.62). Eight reviews reported similar complications in the two groups. The pooled hazard ratio of complications was 0.81 (95%CI: 0.66-1). CONCLUSIONS: The use of surgical mesh is likely effective and safe in the prevention of parastomal hernias without an increased risk of overall complications.

A systematic review and meta-analysis of high-quality randomized controlled trials on the role of prehabilitation programs in colorectal surgery.

BACKGROUND: Prehabilitation is gaining popularity in colorectal surgery but lacks high-quality postoperative outcomes data. This meta-analysis explored whether prehabilitation impacts postoperative outcomes. METHODS: In this meta-analysis, compliant with Preferred Reporting Items for Systematic reviews and Meta-Analyses, we searched PubMed and Scopus through November 2022. High-quality randomized control trials involving adults who underwent colorectal surgery with/without exercise-based prehabilitation were included. The main outcomes were short-term postoperative morbidity, readmissions, and length of stay. Random-effect meta-analyses were performed, and statistical heterogeneity was assessed using the I2 statistic. RESULTS: Seven high-quality randomized control trials comprising 1,225 patients were included. The median prehabilitation duration was 4 (2-4) weeks. Four studies compared prehabilitation and standard of care, and 3 compared prehabilitation and rehabilitation. Exercise-based prehabilitation did not reduce the odds of short-term complications (odds ratio 0.62, 95% confidence interval 0.27-1.40, P = .25, I2 = 68%) or readmission (odds ratio 1, 95% confidence interval 0.73-1.46, P = .85, I2 = 0%). The prehabilitation group had shorter length of hospital stay (weighted mean difference -0.2, 95% confidence interval -0.25 to -0.14, P < .0001, I2 = 43.3%). Prehabilitation and rehabilitation had similar odds of short-term complications (odds ratio 1.03, 95% confidence interval 0.56-1.89, P = .91, I2 = 33%), length of stay (weighted mean difference -0.16, 95% confidence interval -0.47 to 0.16, P = .33, I2 = 59%), and readmission (odds ratio 1.25, 95% confidence interval 0.28-5.56, P = .77, I2 = 52%). The only benefit of prehabilitation over rehabilitation was better 6-minute walking distance test results at time of surgery (weighted mean difference: -9.4 m; 95% confidence interval -18.04 to 0.79, P = .03, I2 = 42%). CONCLUSION: Prehabilitation provided decreased postoperative length of hospital stay and improved preoperative functional outcomes, but not reduced odds of complications and/or readmissions. Prehabilitation and rehabilitation had similar clinical outcomes.

Accuracy of Clinical Staging of Localized Colon Cancer: A National Cancer Database Cohort Analysis.

BACKGROUND: This study aimed to assess concordance between clinical and pathologic assessment of colon cancer. PATIENTS AND METHODS: A retrospective cohort analysis of patients with stage I-III colon cancer in the National Cancer Database (2010-2019) was conducted. Concordance between clinical and pathologic assessment of colon cancer was calculated using Kappa coefficients and 95% confidence intervals (CIs). RESULTS: A total of 125,473 patients (51.2% female; mean age 68.2 years) were included. There was moderate concordance between clinical and pathologic T stage (Kappa = 0.606, 95%CI: 0.602-0.609) and between clinical and pathologic N stage (Kappa = 0.506, 95%CI: 0.501-0.511). For right-sided colon cancer, there was moderate agreement between clinical and pathologic T stage (Kappa = 0.594, 95%CI: 0.589-0.599) and N stage (Kappa = 0.530, 95%CI: 0.523-0.537). For left-sided colon cancer, there was substantial agreement between clinical and pathologic T stage (Kappa = 0.624, 95%CI: 0.619-0.630) and moderate agreement between N stage (Kappa 0.472, 95%CI: 0.463-0.480). Sensitivity of clinical assessment of T and N stage ranged from 64.3% to 77.2% and 41.6% to 54.5%, respectively. Specificity ranged from 96.7% to 97.7% for T stage and 95.7% to 97.3% for N stage. CONCLUSIONS: Clinical assessment of T and N stages of colon cancer had good diagnostic accuracy with moderate concordance with the final pathologic stage. While clinical assessment was highly specific with < 3% of patients being over-staged, it had modest sensitivity, especially for detection of nodal involvement. Diagnostic accuracy of clinical assessment of right and left colon cancers was similar, except for higher sensitivity and accuracy of assessment of nodal involvement in right than left colon cancers.

Low-pressure versus standard-pressure pneumoperitoneum in minimally invasive colorectal surgery: a systematic review, meta-analysis, and meta-regression analysis.

Background: We aimed to assess the efficacy and safety of low-pressure pneumoperitoneum (LPP) in minimally invasive colorectal surgery. Methods: A PRISMA-compliant systematic review/meta-analysis was conducted, searching PubMed, Scopus, Google Scholar, and clinicaltrials.gov for randomized-controlled trials assessing outcomes of LPP vs standard-pressure pneumoperitoneum (SPP) in colorectal surgery. Efficacy outcomes [pain score in post-anesthesia care unit (PACU), pain score postoperative day 1 (POD1), operative time, and hospital stay] and safety outcomes (blood loss and postoperative complications) were analyzed. Risk of bias2 tool assessed bias risk. The certainty of evidence was graded using GRADE. Results: Four studies included 537 patients (male 59.8%). LPP was undertaken in 280 (52.1%) patients and associated with lower pain scores in PACU [weighted mean difference: -1.06, 95% confidence interval (CI): -1.65 to -0.47, P = 0.004, I 2 = 0%] and POD1 (weighted mean difference: -0.49, 95% CI: -0.91 to -0.07, P = 0.024, I 2 = 0%). Meta-regression showed that age [standard error (SE): 0.036, P < 0.001], male sex (SE: 0.006, P < 0.001), and operative time (SE: 0.002, P = 0.027) were significantly associated with increased complications with LPP. In addition, 5.9%-14.5% of surgeons using LLP requested pressure increases to equal the SPP group. The grade of evidence was high for pain score in PACU and on POD1 postoperative complications and major complications, and blood loss, moderate for operative time, low for intraoperative complications, and very low for length of stay. Conclusions: LPP was associated with lower pain scores in PACU and on POD1 with similar operative times, length of stay, and safety profile compared with SPP in colorectal surgery. Although LPP was not associated with increased complications, older patients, males, patients undergoing laparoscopic surgery, and those with longer operative times may be at risk of increased complications.

Risk factors for complications following sacral neuromodulation for faecal incontinence: Long-term follow-up.

AIM: Sacral neuromodulation (SNM) has become a standard surgical treatment for faecal incontinence (FI). Prior studies have reported various adverse events of SNM, including suboptimal therapeutic response, infection, pain, haematoma, and potential need for redo SNM. The aim of this study was to identify the risk factors associated with long-term complications of SNM. METHOD: This retrospective cohort reviewed patients who underwent two-stage SNM for FI at our institution between 2011-2021. Preoperative baseline characteristics and follow-up were obtained from the medical record and/or by telephone interview. Management and outcome of each postoperative event were evaluated by univariate and multivariate regression analyses. RESULTS: A total of 291 patients (85.2% female) were included in this study. Postoperative complications were recorded in 219 (75.2%) patients and 154 (52.9%) patients required surgical intervention to treat complications. The most common postoperative event was loss of efficacy (46.4%). Other common adverse events were problems at the implant site (pain, infection, etc.) in 16.5% and pain during stimulation in 11.7%. Previous vaginal delivery (OR 2.74, p = 0.003) and anal surgery (OR = 2.46, p = 0.039) were independent predictors for complications. Previous colorectal (OR = 2.04, p = 0.026) and anal (OR = 1.98, p = 0.022) surgery and history of irritable bowel syndrome (IBS) (OR = 3.49, p = 0.003) were independent predictors for loss of efficacy. CONCLUSION: Postoperative adverse events are frequently recorded after SNM. Loss of efficacy is the most common. Previous colorectal or anal surgery, vaginal delivery, and IBS are independent risk factors for complications.

Trans­anal minimally invasive surgery (TAMIS) versus rigid platforms for local excision of early rectal cancer: a systematic review and meta-analysis of the literature.

BACKGROUND: Available platforms for local excision (LE) of early rectal cancer are rigid or flexible [trans­anal minimally invasive surgery (TAMIS)]. We systematically searched the literature to compare outcomes between platforms. METHODS: PRISMA-compliant search of PubMed and Scopus databases until September 2022 was undertaken in this random-effect meta-analysis. Statistical heterogeneity was assessed using I2 statistic. Studies comparing TAMIS versus rigid platforms for LE for early rectal cancer were included. Main outcome measures were intraoperative and short-term postoperative outcomes and specimen quality. RESULTS: 7 studies were published between 2015 and 2022, including 931 patients (423 females); 402 underwent TAMIS and 529 underwent LE with rigid platforms. Techniques were similar for operative time (WMD 11.1, 95%CI - 2.6 to 25, p = 0.11), percentage of defect closure (OR 0.7, 95%CI 0.06-8.22, p = 0.78), and peritoneal violation (OR 0.41, 95%CI 0.12-1.43, p = 0.16). Rigid platforms had higher rates of short-term complications (19.1% vs 14.2, OR 1.6, 95%CI 1.07-2.4, p = 0.02), although no significant differences were seen for major complications (OR 1.41, 95%CI 0.61-3.23, p = 0.41). Patients in the rigid platforms group were 3-times more likely to be re-admitted within 30 days compared to the TAMIS group (OR 3.1, 95%CI 1.07-9.4, p = 0.03). Rates of positive resection margins (rigid platforms: 7.6% vs TAMIS: 9.34%, OR 0.81, 95%CI 0.42-1.55, p = 0.53) and specimen fragmentation (rigid platforms: 3.3% vs TAMIS: 4.4%, OR 0.74, 95%CI 0.33-1.64, p = 0.46) were similar between the groups. Salvage surgery was required in 5.5% of rigid platform patients and 6.2% of TAMIS patients (OR 0.8, 95%CI 0.4-1.8, p = 0.7). CONCLUSION: TAMIS or rigid platforms for LE seem to have similar operative outcomes and specimen quality. The TAMIS group demonstrated lower readmission and overall complication rates but did not significantly differ for major complications. The choice of platform should be based on availability, cost, and surgeon's preference.

Artificial intelligence-assisted decision making: Prediction of optimal level of distal mesorectal margin during transanal total mesorectal excision (taTME) using deep neural network modeling.

BACKGROUND: With steep posterior anorectal angulation, transanal total mesorectal excision (taTME) may have a risk of dissection in the wrong plane or starting higher up, resulting in leaving distal mesorectum behind. Although the distal mesorectal margin can be assessed by preoperative MRI, it needs skilled radiologist and high-definition image for accurate evaluation. This study developed a deep neural network (DNN) to predict the optimal level of distal mesorectal margin. METHODS: A total of 182 pelvic MRI images extracted from the cancer image archive (TCIA) database were included. A DNN was developed using gender, the degree of anterior and posterior anorectal angles as input variables while the difference between anterior and posterior mesorectal distances from anal verge was selected as a target. The predictability power was assessed by regression values (R) which is the correlation between the predicted outputs and actual targets. RESULTS: The anterior angle was an obtuse angle while the posterior angle varied from acute to obtuse with mean angle difference 35.5°±14.6. The mean difference between the anterior and posterior mesorectal end distances was 18.6±6.6mm. The developed DNN had a very close correlation with the target during training, validation, and testing (R=0.99, 0.81, and 0.89, P<0.001). The predicted level of distal mesorectal margin was closely correlated with the actual optimal level (R=0.91, P<0.001). CONCLUSIONS: Artificial intelligence can assist in either making or confirming the preoperative decisions. Furthermore, the developed model can alert the surgeons for this potential risk and the necessity of re-positioning the proctectomy incision.

Non-operative management of rectal cancer: Highlighting the controversies.

There remains much ambiguity on what non-operative management (NOM) of rectal cancer truly entails in terms of the methods to be adopted and the best algorithm to follow. This is clearly shown by the discordance between various national and international guidelines on NOM of rectal cancer. The main aim of the NOM strategy is organ preservation and avoiding unnecessary surgical intervention, which carries its own risk of morbidity. A highly specific and sensitive surveillance program must be devised to avoid patients undergoing unnecessary surgical interventions. In many studies, NOM, often interchangeably called the Watch and Wait strategy, has been shown as a promising treatment option when undertaken in the appropriate patient population, where a clinical complete response is achieved. However, there are no clear guidelines on patient selection for NOM along with the optimal method of surveillance.