Endoscopic and trans-anal local excision vs. radical resection in the treatment of early rectal cancer: A systematic review and network meta-analysis.

PURPOSE: The management of early-stage rectal cancer in clinical practice is controversial. The aim of this network meta-analysis was to compare oncological and postoperative outcomes for T1T2N0M0 rectal cancers managed with local excision in comparison to conventional radical resection. METHODS: A systematic review of Medline, Embase and Cochrane electronic databases was performed. Relevant studies were selected using PRISMA guidelines. The primary outcomes measured were 5-year local recurrence and overall survival. Secondary outcomes included rates of postoperative complication, 30-day mortality, positive margin and permanent stoma formation. RESULTS: Three randomized controlled trials and 27 observational studies contributed 8570 patients for analysis. Radical resection was associated with reduced 5-year local recurrence in comparison to local excision. This was statistically significant in comparison to trans-anal local excision (odds ratio (OR) 0.23; 95% confidence interval 0.16-0.30) and favourable in comparison to endoscopic techniques (OR 0.40; 95% confidence interval 0.13-1.23) although this did not reach clinical significance. Positive margin rates were lowest for radical resection. However, 30-day mortality rates, perioperative complications and permanent stoma rates all favoured local excision with no statistically significant difference between endoscopic and trans-anal techniques. CONCLUSION: Radical resection of early rectal cancer is associated with the lowest 5-year local recurrence rates and the lowest rate of positive margins. However, this must be balanced with its higher 30-day mortality and complication rates as well as the increased risk of permanent stoma. The emerging potential role of neoadjuvant therapy prior to local resection, and the heterogeneity of its use, as an alternative treatment for early rectal cancer further complicates the treatment paradigm and adds to controversy in this field.

Robotic-assisted versus laparoscopic rectal surgery in obese and morbidly obese patients: ACS-NSQIP analysis.

Laparoscopic rectal surgery within the confines of a narrow pelvis may be associated with a high rate of open conversion. In the obese and morbidly obese patient, the complexity of laparoscopic surgery increases substantially. Robotic technology is known to reduce the risk of conversion, but it is unclear if it can overcome the technical challenges associated with obesity. The ACS NSQIP database was used to identify obese patients who underwent elective laparoscopic or robotic-assisted rectal resection from 2015 to 2016. Obesity was defined as a body mass index (BMI) greater than or equal to 30 kg/m2. Morbid obesity was defined as a BMI greater than or equal to 35 kg/m2. The primary outcome was unplanned conversions to open. Other outcomes measures assessed included anastomotic leak, operative time, surgical site infections, length of hospital stay, readmissions and mortality. Statistical analyses were performed using SPSS 22.0 (IBM SPSS, USA). 1490 patients had robotic-assisted and 4967 patients had laparoscopic rectal resections between 2015 and 2016. Of those patients, 561 obese patients had robotic-assisted rectal resections and 1824 patients underwent laparoscopic rectal surgery. In the obese cohort, the rate of unplanned conversion to open in the robotic group was 14% compared to 24% in the laparoscopic group (P < 0.0001). Median operative time was significantly longer in the robotic group (248 min vs. 215 min, P < 0.0001). There was no difference in anastomotic leak or systemic sepsis between the laparoscopic and robotic rectal surgery groups. In morbidly obese patients (BMI ≥ 35 kg/m2), the rate of unplanned conversion to open in the robotic group was 19% compared to 26% in the laparoscopic group (P < 0.027). There was no difference in anastomotic leak, systemic sepsis or surgical site infection rates between robotic and laparoscopic rectal resection. Multivariate analysis showed that robotic-assisted surgery was associated with fewer unplanned conversions to open (OR 0.28, P < 0.0001). Robotic-assisted surgery is associated with a decreased risk of conversion to open in obese and morbidly obese patients when compared to conventional laparoscopic surgery. However, robotic surgery was associated with longer operative time and despite improvement in the rate of conversion to open, there was no difference in complications or length of stay. Our findings are limited by the retrospective non-randomised nature of the study, demographic differences between the two groups, and the likely difference in surgeon experience between the two groups. Large randomised controlled studies are needed to further explore the role of robotic rectal surgery in obese and morbidly obese patients.

3D mesenteric angiogram-based assessment of Arc of Riolan crossing the inferior mesenteric vein: important considerations in high ligation during splenic flexure takedown in anterior resection.

BACKGROUND: Recent studies have described the finding of the Arc of Riolan (AoR) crossing the inferior mesenteric vein (IMV) seen during high ligation of IMV while performing minimally invasive colectomies. However, the AoR usually has a medial course, and this variant AoR anatomic course and the clinical importance of its preservation during splenic flexure takedown in anterior resection remains controversial. METHODS: After institutional approval (QA-5775), radiological identification of and mapping of the vessel horizontally crossing the IMV under the pancreas, when present, was performed at a single institution (Westmead Hospital, New South Wales, Australia). One hundred consecutive computed tomographic (CT) mesenteric angiograms conducted in 2018 were reviewed retrospectively to determine the presence of a vessel horizontally crossing the IMV. 3D reconstructions were used to map out its course to understand its origin and full course. Baseline characteristics, including demographic and comorbidity data, were obtained from the medical record. RESULTS: On 3D mesenteric angiogram reconstructions, a vessel crossing anterior to the IMV was present in 11 of 98 cases (11.2%). Two cases were excluded as the presence of this vessel was indeterminate. Eight of 11 patients (72.7%) were male, and the mean age was 49.3 years (range: 21-80 years). There was no statistically significant difference in age and comorbidities between the groups. Importantly, in all 11 cases, there was an arterial vessel crossing the IMV originating from the SMA and communicating with the IMA or a branch of the IMA, proving definitively that this vessel was by definition the AoR. CONCLUSION: This 3D mesenteric angiogram mapping study has shown definitively that the vessel horizontally crossing anterior to the IMV and inferior to the pancreas is an arterial vessel from the SMA to IMA, and by definition the Arc of Riolan. When present, identification and preservation of this collateral arterial vessel during splenic flexure takedown in anterior resection may be important in reducing the risk of post-operative bowel ischaemia.

Attitudes towards Enhanced Recovery after Surgery (ERAS) interventions in colorectal surgery: nationwide survey of Australia and New Zealand colorectal surgeons.

BACKGROUND: Whilst Enhanced Recovery after Surgery (ERAS) has been widely accepted in the international colorectal surgery community, there remains significant variations in ERAS programme implementations, compliance rates and best practice recommendations in international guidelines. METHODS: A questionnaire was distributed to colorectal surgeons from Australia and New Zealand after ethics approval. It evaluated specialist attitudes towards the effectiveness of specific ERAS interventions in improving short term outcomes after colorectal surgery. The data were analysed using a rating scale and graded response model in item response theory (IRT) on Stata MP, version 15 (StataCorp LP, College Station, TX). RESULTS: Of 300 colorectal surgeons, 95 (31.7%) participated in the survey. Of eighteen ERAS interventions, this study identified eight strategies as most effective in improving ERAS programmes alongside early oral feeding and mobilisation. These included pre-operative iron infusion for anaemic patients (IRT score = 7.82 [95% CI: 6.01-9.16]), minimally invasive surgery (IRT score = 7.77 [95% CI: 5.96-9.07]), early in-dwelling catheter removal (IRT score = 7.69 [95% CI: 5.83-9.01]), pre-operative smoking cessation (IRT score = 7.68 [95% CI: 5.49-9.18]), pre-operative counselling (IRT score = 7.44 [95% CI: 5.58-8.88]), avoiding drains in colon surgery (IRT score = 7.37 [95% CI: 5.17-8.95]), avoiding nasogastric tubes (IRT score = 7.29 [95% CI: 5.32-8.8]) and early drain removal in rectal surgery (IRT score = 5.64 [95% CI: 3.49-7.66]). CONCLUSIONS: This survey has demonstrated the current attitudes of colorectal surgeons from Australia and New Zealand regarding ERAS interventions. Eight of the interventions assessed in this study including pre-operative iron infusion for anaemic patients, minimally invasive surgery, early in-dwelling catheter removal, pre-operative smoking cessation, pre-operative counselling, avoidance of drains in colon surgery, avoiding nasogastric tubes and early drain removal in rectal surgery should be considered an important part of colorectal ERAS programmes.

The impact of variations in care and complications within a colorectal Enhanced Recovery After Surgery program on length of stay.

PURPOSE: Enhanced Recovery After Surgery (ERAS) has become standard of care in colorectal surgery. However, there is not a universally accepted colorectal ERAS protocol and significant variations in care exist between institutions. The aim of this study was to examine the impact of variations in ERAS interventions and complications on length of stay (LOS). METHODS: This study was a single-center review of the first 200 consecutive patients recruited into our prospectively collected ERAS database. The primary outcome of this study was to examine the rate of compliance to ERAS interventions and the impact of these interventions on LOS. The secondary outcome was to assess the impact of complications (anastomotic leak, ileus, and surgical site infections) on LOS. ERAS interventions, rate of adherence, LOS, readmissions, morbidity, and mortality were recorded, and statistical analysis was performed. RESULTS: ERAS variations and complications significantly influenced patient LOS on both univariate and multivariate analysis. ERAS interventions identified as the most important strategies in reducing LOS included laparoscopic surgery, mobilization twice daily postoperative day (POD) 0 to 1, discontinuation of intravenous fluids on POD 0 to 1, upgrading to solid diet by POD 0 to 2, removal of indwelling catheter by POD 0 to 2, avoiding nasogastric tube reinsertion and removing drains early. Both major and minor complications increased LOS. Anastomotic leak and ileus were associated with the greatest increase in LOS. CONCLUSION: Seven high-yield ERAS interventions reduced LOS. Major and minor complications increased LOS. Reducing variations in care and complications can improve outcomes following colorectal surgery.

Can adjuvant pelvic radiation therapy after local excision or polypectomy for T1 and T2 rectal cancer offer an alternative option to radical surgery?

PURPOSE: To determine outcomes after adjuvant pelvic local radiation therapy (RT) +/- concurrent chemotherapy for T1 and T2 rectal carcinomas treated with local excision or polypectomy. METHODS: We retrospectively identified adult patients with histologically proven T1 and T2 rectal adenocarcinoma, diagnosed incidentally at time of local excision or polypectomy between 01 January 2007 and 31 December 2019, and appropriately staged to confirm N0 M0 status. Patients were excluded if they had recurrent cancer or had received total mesorectal excision (TME): anterior resection (AR) or abdominoperineal resection (APR). Patient, tumour and treatment factors, together with disease and toxicity outcomes were collected from institutional medical records, correspondence and investigation reports. Descriptive statistical analyses were employed. The primary endpoint was loco-regional control and secondary endpoints were treatment-related toxicity, disease free survival, overall survival and rate of surgical salvage for pelvic recurrence. RESULTS: The median age of the 15 eligible patients was 73 (range 49-82 years). There were 9 men (60%) and 6 women (40%). The majority had T1 disease (80%) and most had received endomucosal resection (80%). All patients received 43-52Gy (EQD2) to the primary and 43-48Gy (EQD2) to the pelvis with 46.6% receiving concurrent chemotherapy (infusional 5-FU or oral capecitabine). At median follow up of 51 months, there were no local or regional recurrences. One patient experienced an isolated distant relapse at 48 months without any locoregional recurrence. CONCLUSION: Our findings demonstrate good locoregional disease control with the use of adjuvant pelvic RT for T1 and T2 rectal adenocarcinoma initially treated with polypectomy or local (non-oncological) excision. These findings indicate that adjuvant pelvic RT may provide an alternative to TME surgery in patients with incidentally detected early rectal cancers.

Multiple caecal granular cell tumours-a case report.

Granular cell tumours (GCTs) are generally benign neoplasms, which are believed to be of neural origin. They are uncommon in the gastrointestinal tract. They are rarely found in the colon and even more rarely found to be multiple. We present a case of a man who underwent a right hemicolectomy for a submucosal lesion and polyps and was found to have multiple nodules diagnosed as caecal GCTs with cellular atypia. While uncommon, this case shows it remains an important differential due to implications for patient management, given the often benign nature of disease.

The effect of socioeconomic deprivation on presentation stage and long-term outcomes in patients undergoing colorectal cancer resection in Western Sydney.

BACKGROUND: While socioeconomic deprivation has been shown to affect survival in colorectal cancer, other factors such as global region of birth and ethnicity also exert an effect. We wished to ascertain the influence of socioeconomic deprivation on stage of presentation and cancer survival in an ethnically diverse Australian population. METHODS: Cases from a database of resections in Western Sydney (n = 1596) were stratified into cohorts of socioeconomic quintiles. Univariate analysis was used to compare demographics, AJCC stage and histopathological details between the least and most socioeconomically deprived groups. Kaplan-Meier analysis and log-rank testing were used to compare cancer-specific and all-cause 5-year survival between the most deprived quintile and all others, after case-control matching for age and overseas birth. RESULTS: A total of 322 (20.2%) patients from the most socioeconomically deprived centile, and 275 (17.2%) from the least were compared. The most deprived were significantly more likely to be aged under 70 (54.1% vs. 44.4%, p = 0.019), born overseas (54.3% vs. 38.6%, p = 0.003), present with stage III disease (37.4% vs. 26.7%, p = 0.005), perforated (12.5% vs. 5.3%, p = 0.005) or circumferential tumours (37% vs. 24.3%, p = 0.043). There was no significant difference in proportions presenting with metastatic disease, or 5-year survival between the most deprived quintile and all others after correction for age and foreign birth. CONCLUSIONS: Socioeconomic deprivation is associated with unfavourable colorectal cancer presentation stage but not poorer 5-year survival in our Western Sydney population. The reasons for this are unclear and demand further attention.

Outcomes of young patients diagnosed with locally advanced rectal cancer.

BACKGROUND: The incidence of rectal cancer is higher in the older population. In developed nations, there has been a rise in incidence in young onset colorectal cancer (CRC). We examined the outcomes of locally advanced rectal cancer (LARC) in younger patients (yRC) compared with older patients, using a retrospective audit. METHODS: All cases of LARC referred to two tertiary referral cancer centres in Western Sydney were examined. Patient demographics, presenting symptoms, treatment, relapse free survival (RFS), overall survival (OS) and progression free survival (PFS) were obtained. Under 50 years old was used as the cut-off age for defining yRC. RESULTS: All 145 consecutive patients were treated for LARC, including 28 in the yRC and 117 in the older patient group. Median follow-up was 54 months. yRC were more likely to complete neoadjuvant therapy (100% vs. 86%; P=0.032) and to undergo more extensive surgical procedures (24% vs. 2%, P<0.0001). yRC were more likely to have microsatellite high (MSI) tumours (30% vs. 4.7%; P=0.003). yRC demonstrated significantly poorer RFS compared with the standard group (HR 2.79; median RFS 4.67 vs. 16.02 months; P=0.023). In the relapsed setting, yRC had poorer PFS compared with the standard group (median PFS 2.66 vs. 9.70, P=0.006, HR 3.04). A difference in OS was also seen between the two groups, with yRC demonstrating poorer OS (median OS 40.46 vs. 58.26 months, HR 3.48, P=0.036). CONCLUSIONS: Patients under 50 years with LARC are more likely to have MSI tumours with a more aggressive disease course and poorer RFS, PFS and OS. Initiatives to improve early detection of these patients may improve outcomes. Further research is necessary to understand this disease and optimise its treatment.

Bowel Preparation and Oral Antibiotic Agents for Selective Decontamination in Colorectal Surgery: Current Practice, Perspectives, and Trends in Australia and New Zealand, 2019-2020.

Background: There has been much debate as to the importance of mechanical bowel preparation (MBP) and oral antibiotic agents (OAB) prior to elective colorectal surgery over the past two decades. There is no consensus between international guidelines. Methods: The Australia and New Zealand Mechanical Bowel Preparation and Oral Antibiotics (ANZ-MBP-OAB) questionnaire was distributed to colorectal surgeons after institutional board approval assessing specialist attitudes toward 18 enhanced recovery after surgery (ERAS) interventions. Data were analyzed using a rating scale and graded response model in item response theory (IRT) on Stata MP, version 15 (StataCorp LP, College Station, TX). Specialist attitudes toward the effectiveness of MBP and OAB strategies in providing better short-term outcomes was ranked alongside other ERAS interventions. This was followed by specific questions examining current practice, perspectives, and trends. Results: Ninety-five of 300 (31.7%) colorectal surgeons in Australia and New Zealand participated in the survey. Statistical modeling was achieved in 13 ERAS interventions. Compared with other ERAS interventions, the use of MBP with OAB and MBP alone ranked nine of 13 and 10 of 13, respectively, in order of effectiveness in providing better short-term outcomes after colorectal surgery. Oral antibiotic agents alone was not considered effective. Mechanical bowel preparation with OAB was considered to be the best strategy in both colon (37%) and rectal surgery (48%) but current practice varied substantially from perspective. Mechanical bowel preparation alone was strongly favored in rectal surgery (81%) with only 14% using MBP with OAB. In colon surgery, only 10% used MBP with OAB, with MBP alone (45%) and no preparation (45%) being equally the most commonly used strategies. Conclusions: Among Australian and New Zealand colorectal surgeons, MBP with OAB was considered the best bowel preparation strategy. However, despite an awareness of its benefits, MBP with OAB has yet to be widely adopted into clinical practice or guidelines in Australia and New Zealand.

Accuracy of estimation of polyp size at colonoscopy.

BACKGROUND: The Cancer Council posits that the size of adenomas is a more robust marker of risk than histological characteristics. The purpose of our study is to assess the accuracy of estimation of polyp size at colonoscopy amongst different levels of endoscopists and compare this with histopathological size. METHODS: A retrospective review of prospectively collected data was performed. Specimens were included if they were (i) from patients aged 18 years or older, (ii) polyp obtained at colonoscopy, (iii) measured in quantitative units and (iv) the largest eligible polyp per patient. RESULTS: A total of 92 patients were included. Our results demonstrate that the relationship between the histological size of a polyp and an endoscopist's estimate depended upon seniority level (P = 0.001). Senior consultants tended to overestimate lesion size (P < 0.001), fellows/junior consultants tended to underestimate size (P = 0.010), whilst registrars' estimates demonstrated no systematic difference from histological size (P = 0.518). The ratio of a senior consultant's estimate of polyp size to histological size was on average 74% with their estimates ranging from 31% to 173%. The corresponding estimates are 123% (32-470%) for fellows/junior consultants and 107% (35-334%) for registrars. CONCLUSION: Our study demonstrates that senior consultants are more precise with more junior endoscopists having a great degree of variability in their practice. It is evident that there is a relationship between proceduralist experience and polyp size estimation. It is, therefore, important to consider the ways in which we can mitigate this learning curve and continue to develop technology to improve our accuracy.

Clinicopathological factors associated with positive circumferential margins in rectal cancers.

BACKGROUND: Positive circumferential resections are associated with local disease recurrence and reduced survival in rectal cancer. We studied a cohort of consecutive rectal cancer resections to assess for clinicopathological differences and survival in patients with positive and negative circumferential margins. METHODS: Rectal cancers were identified from a retrospective histopathology database of colorectal resections performed at five western Sydney hospitals from 2010 to 2016. Univariate and multivariate analysis with binary logistic regression were performed on histopathology data matched with survival times from the New South Wales Registry of Births Deaths and Marriages. RESULTS: A total of 502 rectal cancer patients were identified including 66 (13.1%) with involved circumferential margins. Patients with positive and negative circumferential margins had a similar distribution of age, gender and use of neoadjuvant radiotherapy. Tumours with involved circumferential margin comprised 98.5% T3 and T4 disease of which 51.5% received neoadjuvant radiotherapy. These were significantly associated with metastatic disease, increasing tumour size, circumferential and perforated tumours on univariate analysis. Multivariate analysis identified abdomino-perineal resection (odds ratio (OR) 3.35; P = 0.003), en-bloc multivisceral resection (OR 2.56; P = 0.032), T4 stage (OR 6.99; P < 0.001), perineural (OR 5.61; P < 0.001) and vascular invasion (OR 2.46; P = 0.022) as independent risk factors. Five-year survival was significantly worse for patients with involved circumferential margins (26% versus 69%; P < 0.001). CONCLUSION: Circumferential margin status reflects not only technical success but also aggressive disease phenotypes which require adjuvant therapy. Further work is needed to determine whether omission of radiotherapy has had an effect on long-term outcomes in some of our at-risk patients.

Does a stoma reduce the risk of anastomotic leak and need for re-operation following low anterior resection for rectal cancer: systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: There is a relatively high risk of anastomotic leak in low anterior resection (LAR), associated with significant morbidity and mortality. This systematic review and meta-analysis aims to compare diverting stoma vs. no stoma for LAR in terms of leak rates, reoperations, mortality rates and complication rates. METHODS: We systematically performed electronic searches of databases Ovid Medline, PubMed, CCTR, CDSR, ACP Journal Club and DARE from inception to present. Only randomized controlled trials comparing LAR for rectal cancer with versus without stoma diversion were included for analysis. Main outcomes were anastomotic leak, reoperation rate and mortality. Secondary outcomes included other operative and stoma-related complications. RESULTS: Eight randomized controlled trials were included in the study for qualitative and quantitative analyses. A significantly longer operative duration for patients with stoma diversion was seen (WMD 19.50 min; 95% CI: 7.38, 31.63; I2=0%, P=0.002). The pooled rate for anastomotic leak was significantly lower for those with stoma diversion (6.3% vs. 18.3%; RR 0.36; 95% CI: 0.24, 0.54; I2=0%; P<0.00001). There was lower reoperation rate for patients with stoma diversion compared to no stoma (5.9% vs. 16.7%; RR 0.40; 95% CI: 0.26, 0.60; I2=0%; P<0.00001). No significant difference was found in terms of leak-related mortality between stoma vs. no-stoma cohorts (0.47% vs. 1.0%; P=0.51). CONCLUSIONS: The present meta-analysis suggests a diverting or defunctioning stoma following LAR for rectal cancers can reduce anastomotic leak and reoperation rates, without increased risk of mortality or other complications.

The role of mechanical bowel preparation and oral antibiotics for left-sided laparoscopic and open elective restorative colorectal surgery with and without faecal diversion.

BACKGROUND: There is significant variation in the use of mechanical bowel preparation and oral antibiotics prior to left-sided elective colorectal surgery. There has been no consensus internationally. METHODS: This was a retrospective analysis of the 2015 American College of Surgeons National Surgical Quality Improvement Program database. Patients were divided into four groups: those who had mechanical bowel preparation with oral antibiotics, mechanical bowel preparation alone, oral antibiotics alone and no preparation. The main outcome measures included overall, superficial, deep and organ/space surgical site infections. Secondary outcomes included anastomotic leak, ileus and rate of Clostridium difficile. RESULTS: A total of 5729 patients were included for analysis. The overall surgical site infection rate (any superficial, deep or organ/space infection) was significantly lower in the mechanical bowel preparation and oral antibiotics approach when compared to no preparation (OR = 0.46, 95% CI 0.36-0.59, P < 0.0001). On multivariable logistic regression analysis, mechanical bowel preparation with oral antibiotics maintained a lower risk of overall surgical site infections. MBP and OAB also had a protective effect on anastomotic leak in both the laparoscopic and open cohorts (laparoscopic multivariable adjusted OR = 0.42 (0.19-0.94), P = 0.035; open multivariable adjusted OR = 0.3 (0.12-0.77), P = 0.012). Mechanical bowel preparation alone and oral antibiotics alone was not associated with a significant decrease in surgical site infections. There was no increase in C. difficile occurrences with the use of oral antibiotics. CONCLUSION: Mechanical bowel preparation with oral antibiotics significantly minimised surgical site infections and anastomotic leak following both laparoscopic and open left-sided restorative colorectal surgery. Mechanical bowel preparation alone did not reduce surgical site infections. There was a trend to reduction in surgical site infections with oral antibiotics alone.

Rectal perforation following paclitaxel and carboplatin chemotherapy for advanced ovarian cancer: a case report and review of the literature.

BACKGROUND: Paclitaxel is a chemotherapy drug commonly used in the management of ovarian cancer. Colonic perforation is an extremely rare complication of paclitaxel administration with few case reports in the medical literature. We report a case of a patient with advanced ovarian cancer who had a rectal perforation following administration of paclitaxel. There has only been one other case report of rectal perforation in the medical literature following paclitaxel therapy. CASE PRESENTATION: A 55-year-old Caucasian woman with advanced ovarian cancer awaiting elective debulking surgery for her tumor presented to our emergency department with abdominal pain, vomiting, and diarrhea. She was admitted to hospital for neoadjuvant chemotherapy and management of her systemic symptoms. She became acutely unwell following one cycle of chemotherapy with paclitaxel. A computed tomography scan of her abdomen showed typhlitis of her descending colon and a corresponding rectal perforation. Surgical intervention was deemed inappropriate as she had a heavy burden of disease and neutropenia. She died following a period of conservative management with strong intravenously administered antibiotics. CONCLUSIONS: This case highlights the importance of recognizing gastrointestinal complications following chemotherapy and the need to be aware of the possibility of bowel perforation. Prompt surgical review and intervention must be requested in patients with acute abdominal pain and persistent gastrointestinal symptoms such as diarrhea and vomiting.

Association of Mechanical Bowel Preparation and Oral Antibiotics Before Elective Colorectal Surgery With Surgical Site Infection: A Network Meta-analysis.

Importance: There has been a resurgence of interest in the use of mechanical bowel preparation (MBP) and oral antibiotics (OAB) before elective colorectal surgery. Until now, clinical trials and meta-analyses have not compared all 4 approaches (MBP with OAB, OAB only, MBP only, or no preparation) simultaneously. Objective: To perform a network meta-analysis to clarify which approach in colorectal surgery is associated with the lowest rate of surgical site infection (SSI). Data Sources: Five electronic databases were searched, including PubMed, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, ACP Journal Club. and Database of Abstracts of Review of Effectiveness from database inception to November 27, 2017. Study Selection: Only data from randomized clinical trials were included. Inclusion criteria were RCTs that reported on SSI rates or other complications based on MBP or OAB status. Quality of studies was appraised by the Cochrane Collaboration risk of bias tool. Data Extraction and Synthesis: The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Main Outcomes and Measures: Total, incisional, and organ/space SSI rates. Secondary outcomes included rates of anastomotic leak, mortality, readmissions/reoperations, urinary tract infection, and pulmonary complications. Results: Thirty-eight randomized clinical trials among 8458 patients (52.1% male) were included, providing 4 direct comparisons and 2 indirect comparisons for 8 outcome measures. On Bayesian analysis, MBP with OAB vs MBP only was associated with reduced SSI (odds ratio [OR], 0.71; 95% equal-tail credible interval [CrI], 0.57-0.88). There was no significant difference between MBP with OAB vs OAB only (OR, 0.95; 95% CrI, 0.56-1.62). Oral antibiotics without MBP was not associated with a statistically significant reduction in SSI compared with any other group (except for a risk reduction in organ/space SSI when indirectly compared with no preparation) (OR, 0.13; 95% CrI, 0.02-0.55). There was no difference in SSI between MBP only vs no preparation (OR, 0.84; 95% CrI, 0.69-1.02). Conclusions and Relevance: In this network meta-analysis of randomized clinical trials, MBP with OAB was associated with the lowest risk of SSI. Oral antibiotics only was ranked as second best, but the data available on this approach were limited. There was no difference between MBP only vs no preparation. In addition, there was no difference in rates of anastomotic leak, readmissions, or reoperations between any groups.