The effect of selective decontamination on the intestinal microbiota as measured with IS-pro: a taxonomic classification tool applicable for direct evaluation of intestinal microbiota in clinical routine.

Selective decontamination of the digestive tract (SDD) is aimed at elimination of potential pathogenic microorganisms. In this study, the effect of SDD on gut microbiota was evaluated in a large homogenous group of elective colorectal cancer surgery patients. Rectal swabs were taken from 118 patients undergoing colorectal surgery. These patients were randomly assigned to receive perioperative SDD or to the control group (no SDD). Rectal swabs were taken prior to surgery, 3 days after commencing administration of SDD. Gut microbial profiles were obtained with the IS-pro technique, a standardized microbiota profiling assay applicable in clinical routine. Differences in abundance for different taxonomical groups and diversity between the groups were assessed. Unsupervised and supervised classification techniques were used to assess microbial signatures, differentiating between the SDD group and the control group. Patients in the SDD group had different gut microbial signatures than in the control group, also in phyla that are not a target for SDD. Escherichia coli, Sutterella spp., Faecalibacterium prausnitzii, and Streptococcus spp. were the species that differed the most between the two groups. The SDD group showed clustering into two subgroups. In one subgroup, a decrease in Proteobacteria was observed, whereas the other subgroup showed a shift in Proteobacteria species. This study shows that SDD not only decreases colonization of the gastrointestinal tract with potential pathogenic Gram-negative microorganisms, but also reduces the abundance of normal colonizers of our gastrointestinal system and leads to a shift in total microbiota composition.

Structured training pathway and proctoring; multicenter results of the implementation of transanal total mesorectal excision (TaTME) in the Netherlands.

BACKGROUND: Transanal total mesorectal excision (TaTME) is a new complex technique with potential to improve the quality of surgical mesorectal excision for patients with mid and low rectal cancer. The procedure is technically challenging and has shown to be associated with a relative long learning curve which might hamper widespread adoption. Therefore, a national structured training pathway for TaTME has been set up in the Netherlands to allow safe implementation. The aim of this study was to monitor safety and efficacy of the training program with 12 centers. METHODS: Short-term outcomes of the first ten TaTME procedures were evaluated in 12 participating centers in the Netherlands within the national structured training pathway. Consecutive patients operated during and after the proctoring program for rectal carcinoma with curative intent were included. Primary outcome was the incidence of intraoperative complications, secondary outcomes included postoperative complications and pathological outcomes. RESULTS: In October 2018, 12 hospitals completed the training program and from each center the first 10 patients were included for evaluation. Intraoperative complications occurred in 4.9% of the cases. The clinicopathological outcome reported 100% for complete or nearly complete specimen, 100% negative distal resection margin, and the circumferential resection margin was positive in 5.0% of patients. Overall postoperative complication rate was 45.0%, with 19.2% Clavien-Dindo ≥ III and an anastomotic leak rate of 17.3%. CONCLUSIONS: This study shows that the nationwide structured training program for TaTME delivers safe implementation of TaTME in terms of intraoperative and pathology outcomes within the first ten consecutive cases in each center. However, postoperative morbidity is substantial even within a structured training pathway and surgeons should be aware of the learning curve of this new technique.

Randomized clinical trial of selective decontamination of the digestive tract in elective colorectal cancer surgery (SELECT trial).

BACKGROUND: Infectious complications and anastomotic leakage affect approximately 30 per cent of patients after colorectal cancer surgery. The aim of this multicentre randomized trial was to investigate whether selective decontamination of the digestive tract (SDD) reduces these complications of elective colorectal cancer surgery. METHODS: The effectiveness of SDD was evaluated in a multicentre, open-label RCT in six centres in the Netherlands. Patients with colorectal cancer scheduled for elective curative surgery with a primary anastomosis were eligible. Oral colistin, tobramycin and amphotericin B were administered to patients in the SDD group to decontaminate the digestive tract. Both treatment and control group received intravenous cefazolin and metronidazole for perioperative prophylaxis. Mechanical bowel preparation was given for left-sided colectomies, sigmoid and anterior resections. Anastomotic leakage was the primary outcome; infectious complications and mortality were secondary outcomes. RESULTS: The outcomes for 228 patients randomized to the SDD group and 227 randomized to the control group were analysed. The trial was stopped after interim analysis demonstrated that superiority was no longer attainable. Effective SDD was confirmed by interspace DNA profiling analysis of rectal swabs. Anastomotic leakage was observed in 14 patients (6·1 per cent) in the SDD group and in 22 patients (9·7 per cent) in the control group (odds ratio (OR) 0·61, 95 per cent c.i. 0·30 to 1·22). Fewer patients in the SDD group had one or more infectious complications than patients in the control group (14·9 versus 26·9 per cent respectively; OR 0·48, 0·30 to 0·76). Multivariable analysis indicated that SDD reduced the rate of infectious complications (OR 0·47, 0·29 to 0·76). CONCLUSION: SDD reduces infectious complications after colorectal cancer resection but did not significantly reduce anastomotic leakage in this trial. Registration number: NCT01740947 ( https://www.clinicaltrials.gov).

Urinary volatile organic compound markers and colorectal anastomotic leakage.

AIM: Inflammatory markers such as serum C-reactive protein (CRP) are used as routine markers to detect anastomotic leakage following colorectal surgery. However, CRP is characterized by a relatively low predictive value, emphasizing the need for the development of novel diagnostic approaches. Volatile organic compounds (VOCs) are gaseous metabolic products deriving from all conceivable bodily excrements and reflect (alterations in) the patient's physical status. Therefore, VOCs are increasingly considered as potential non-invasive diagnostic biomarkers. The aim of this study was to assess the diagnostic accuracy of urinary VOCs for colorectal anastomotic leakage. METHODS: In this explorative multicentre study, urinary VOC profiles of 22 patients with confirmed anastomotic leakage and 27 uneventful control patients following colorectal surgery were analysed by field asymmetric ion mobility spectrometry (FAIMS). RESULTS: Urinary VOCs of patients with anastomotic leakage could be distinguished from those of control patients with high accuracy: area under the receiver operating characteristics curve 0.91 (95% CI 0.81-1.00, P < 0.001), sensitivity 86% and specificity 93%. Serum CRP was significantly increased in patients with a confirmed anastomotic leak but with lower diagnostic accuracy compared to VOC analysis (area under the receiver operating characteristics curve 0.82, 95% CI 0.68-0.95, P < 0.001). Combining VOCs and CRP did not result in a significant improvement of the diagnostic performance compared to VOCs alone. CONCLUSION: Analysis by FAIMS allowed for discrimination between urinary VOC profiles of patients with a confirmed anastomotic leak and control patients following colorectal surgery. A superior accuracy compared to CRP and apparently high specificity was observed, underlining the potential as a non-invasive biomarker for the detection of colorectal anastomotic leakage.

Resection of hepatic and pulmonary metastasis from metastatic esophageal and gastric cancer: a nationwide study.

The standard of care for gastroesophageal cancer patients with hepatic or pulmonary metastases is best supportive care or palliative chemotherapy. Occasionally, patients can be selected for curative treatment instead. This study aimed to evaluate patients who underwent a resection of hepatic or pulmonary metastasis with curative intent. The Dutch national registry for histo- and cytopathology was used to identify these patients. Data were retrieved from the individual patient files. Kaplan-Meier survival analysis was performed. Between 1991 and 2016, 32,057 patients received a gastrectomy or esophagectomy for gastroesophageal cancer in the Netherlands. Of these patients, 34 selected patients received a resection of hepatic metastasis (n = 19) or pulmonary metastasis (n = 15) in 21 different hospitals. Only 4 patients received neoadjuvant therapy before metastasectomy. The majority of patients had solitary, metachronous metastases. After metastasectomy, grade 3 (Clavien-Dindo) complications occurred in 7 patients and mortality in 1 patient. After resection of hepatic metastases, the median potential follow-up time was 54 months. Median overall survival (OS) was 28 months and the 1-, 3-, and 5- year OS was 84%, 41%, and 31%, respectively. After pulmonary metastases resection, the median potential follow-up time was 80 months. The median OS was not reached and the 1-, 3-, and 5- year OS was 67%, 53%, and 53%, respectively. In selected patients with gastroesophageal cancer with hepatic or pulmonary metastases, metastasectomy was performed with limited morbidity and mortality and offered a 5-year OS of 31-53%. Further prospective studies are required.

Long-Term Effects of Omitting Antibiotics in Uncomplicated Acute Diverticulitis.

BACKGROUND: Traditionally uncomplicated acute diverticulitis was routinely treated with antibiotics, although evidence for this strategy was lacking. Recently, two randomized clinical trials (AVOD trial and DIABOLO trial) published short-term results of omitting antibiotics compared to routine antibiotic treatment. Both showed no significant differences regarding recovery from the initial episode, as well as rates of complicated or recurrent diverticulitis and sigmoid resection. However, both studies showed a trend of higher rates of sigmoid resection in the observational groups. Here, the long-term effects of omitting antibiotics in first episode uncomplicated acute diverticulitis were assessed. METHODS: A total of 528 patients with CT-proven, primary, left-sided, uncomplicated acute diverticulitis were randomized to either an observational or an antibiotic treatment strategy (DIABOLO trial). Outcome measures were complicated diverticulitis, recurrent diverticulitis and sigmoid resection at 24 months' follow up. Differences between the groups were explored and risk factors were identified using multivariable logistic regression. RESULTS: Complete case analyses showed no difference in rates of recurrent diverticulitis (15.4% in the observational group versus 14.9% in the antibiotic group; p = 0.885), complicated diverticulitis (4.8% versus 3.3%; p = 0.403) and sigmoid resection (9.0% versus. 5.0%; p = 0.085). Young patients (<50 years) and patients with a pain score at presentation of 8 or higher on a visual analogue pain scale were at risk for complicated or recurrent diverticulitis. In this multivariable analysis, treatment type (with or without antibiotics) was not an independent predictor for complicated or recurrent diverticulitis. CONCLUSION: Omitting antibiotics in the treatment of uncomplicated acute diverticulitis did not result in more complicated diverticulitis, recurrent diverticulitis or sigmoid resections at long-term follow up. As the DIABOLO trial was not powered for these secondary outcome measures, some uncertainty remains whether (small) non-significant differences could be true associations.

Cancer survivors' needs during various treatment phases after multimodal treatment for colon cancer - is there a role for eHealth?

BACKGROUND: More colon cancer patients are expected to fully recover after treatment due to earlier detection of cancer and improvements in general health- and cancer care. The objective of this study was to gather participants' experiences with full recovery in the different treatment phases of multimodal treatment and to identify their needs during these phases. The second aim was to propose and evaluate possible solutions for unmet needs by the introduction of eHealth. METHODS: A qualitative study based on two focus group discussions with 22 participants was performed. The validated Supportive Care Needs Survey and the Cancer Treatment Survey were used to form the topic list. The verbatim transcripts were analyzed with Atlas.ti. 7th version comprising open, axial and selective coding. The guidelines of the consolidated criteria for reporting qualitative research (COREQ) were used. RESULTS: Experiences with the treatment for colon cancer were in general positive. Most important unmet needs were 'receiving information about the total duration of side effects', 'receiving information about the minimum amount of chemo needed to overall survival' and 'receiving a longer aftercare period (with additional attention for psychological guidance)'. More provision of information online, a chat function with the oncological nurse specialist via a website, and access to scientific articles regarding the optimal dose of chemotherapy were often mentioned as worthwhile additions to the current health care for colon cancer. CONCLUSIONS: Many of the unmet needs of colon cancer survivors occur during the adjuvant treatment phase and thereafter. To further optimize recovery and cancer care, it is necessary to have more focus on these unmet needs. More attention for identifying patients' problems and side-effects during chemotherapy; and identifying patients' supportive care needs after finishing chemotherapy are necessary. For some of these needs, eHealth in the form of blended care will be a possible solution.

Nationwide comprehensive gastro-intestinal cancer cohorts: the 3P initiative.

BACKGROUND: The increasing sub-classification of cancer patients due to more detailed molecular classification of tumors, and limitations of current trial designs, require innovative research designs. We present the design, governance and current standing of three comprehensive nationwide cohorts including pancreatic, esophageal/gastric, and colorectal cancer patients (NCT02070146). Multidisciplinary collection of clinical data, tumor tissue, blood samples, and patient-reported outcome (PRO) measures with a nationwide coverage, provides the infrastructure for future and novel trial designs and facilitates research to improve outcomes of gastrointestinal cancer patients. MATERIAL AND METHODS: All patients aged ≥18 years with pancreatic, esophageal/gastric or colorectal cancer are eligible. Patients provide informed consent for: (1) reuse of clinical data; (2) biobanking of primary tumor tissue; (3) collection of blood samples; (4) to be informed about relevant newly identified genomic aberrations; (5) collection of longitudinal PROs; and (6) to receive information on new interventional studies and possible participation in cohort multiple randomized controlled trials (cmRCT) in the future. RESULTS: In 2015, clinical data of 21,758 newly diagnosed patients were collected in the Netherlands Cancer Registry. Additional clinical data on the surgical procedures were registered in surgical audits for 13,845 patients. Within the first two years, tumor tissue and blood samples were obtained from 1507 patients; during this period, 1180 patients were included in the PRO registry. Response rate for PROs was 90%. The consent rate to receive information on new interventional studies and possible participation in cmRCTs in the future was >85%. The number of hospitals participating in the cohorts is steadily increasing. CONCLUSION: A comprehensive nationwide multidisciplinary gastrointestinal cancer cohort is feasible and surpasses the limitations of classical study designs. With this initiative, novel and innovative studies can be performed in an efficient, safe, and comprehensive setting.

Randomized clinical trial of observational versus antibiotic treatment for a first episode of CT-proven uncomplicated acute diverticulitis.

BACKGROUND: Antibiotics are advised in most guidelines on acute diverticulitis, despite a lack of evidence to support their routine use. This trial compared the effectiveness of a strategy with or without antibiotics for a first episode of uncomplicated acute diverticulitis. METHODS: Patients with CT-proven, primary, left-sided, uncomplicated, acute diverticulitis were included at 22 clinical sites in the Netherlands, and assigned randomly to an observational or antibiotic treatment strategy. The primary endpoint was time to recovery during 6 months of follow-up. Main secondary endpoints were readmission rate, complicated, ongoing and recurrent diverticulitis, sigmoid resection and mortality. Intention-to-treat and per-protocol analyses were done. RESULTS: A total of 528 patients were included. Median time to recovery was 14 (i.q.r. 6-35) days for the observational and 12 (7-30) days for the antibiotic treatment strategy, with a hazard ratio for recovery of 0·91 (lower limit of 1-sided 95 per cent c.i. 0·78; P = 0·151). No significant differences between the observation and antibiotic treatment groups were found for secondary endpoints: complicated diverticulitis (3·8 versus 2·6 per cent respectively; P = 0·377), ongoing diverticulitis (7·3 versus 4·1 per cent; P = 0·183), recurrent diverticulitis (3·4 versus 3·0 per cent; P = 0·494), sigmoid resection (3·8 versus 2·3 per cent; P = 0·323), readmission (17·6 versus 12·0 per cent; P = 0·148), adverse events (48·5 versus 54·5 per cent; P = 0·221) and mortality (1·1 versus 0·4 per cent; P = 0·432). Hospital stay was significantly shorter in the observation group (2 versus 3 days; P = 0·006). Per-protocol analyses were concordant with the intention-to-treat analyses. CONCLUSION: Observational treatment without antibiotics did not prolong recovery and can be considered appropriate in patients with uncomplicated diverticulitis. Registration number: NCT01111253 (http://www.clinicaltrials.gov).

Training residents in laparoscopic colorectal surgery: is supervised surgery safe?

BACKGROUND: Colorectal resections are increasingly performed laparoscopically, and training in laparoscopic resections in the Netherlands has shifted from a post-residency fellowship to training in residency. The question remains if this supervised surgery affects short-term patient outcome. METHODS: Between January 2010 and July 2014, 523 consecutive patients, who underwent laparoscopic colorectal resection, were selected from a prospective single-center database. All data were obtained from the maintained database and retrospectively analyzed. We compared the short-term outcome of patients who underwent laparoscopic colorectal surgery by a supervised fifth- or sixth-year resident compared to patients who underwent laparoscopic colorectal surgery performed by a dedicated colorectal surgeon. Statistical analysis was performed using the Chi-square test for categorical variables and the t test for continuous variables. RESULTS: Almost 40 % of operations were performed by a resident with an even distribution in type of resection, except for the abdominal-perineal resection (residents vs. surgeon 3.57 vs. 8.26 %, p = 0.04) and the total number of patients who underwent preoperative chemoradiation (resident vs. surgeon 6.66 vs. 20.65 %, p = 0.04). No difference was found in operative time or per-operative blood loss. A higher conversion rate was found when surgery was performed by a supervised resident (residents vs. surgeon 17.34 vs. 9.17 %, p = 0.01), which could be attributed to case selection and one single year. No differences in major complications, oncological outcome and construction of a stoma were found. In the case of minor complications, a significantly increased percentage of bladder retention was found in the surgeon group (residents vs. surgeon 1 vs. 4.6 %, p = 0.03). CONCLUSIONS: In this study, we found that patient safety and short-term outcome are not adversely affected when laparoscopic colorectal surgery is performed by a supervised fifth- or sixth-year resident.

Prognostic value of BRAF and KRAS mutation status in stage II and III microsatellite instable colon cancers.

Microsatellite instability (MSI) has been associated with favourable survival in early stage colorectal cancer (CRC) compared to microsatellite stable (MSS) CRC. The BRAF V600E mutation has been associated with worse survival in MSS CRC. This mutation occurs in 40% of MSI CRC and it is unclear whether it confers worse survival in this setting. The prognostic value of KRAS mutations in both MSS and MSI CRC remains unclear. We examined the effect of BRAF and KRAS mutations on survival in stage II and III MSI colon cancer patients. BRAF exon 15 and KRAS exon 2-3 mutation status was assessed in 143 stage II (n = 85) and III (n = 58) MSI colon cancers by high resolution melting analysis and sequencing. The relation between mutation status and cancer-specific (CSS) and overall survival (OS) was analyzed using Kaplan-Meier and Cox regression analysis. BRAF V600E mutations were observed in 51% (n = 73) and KRAS mutations in 16% of cases (n = 23). Patients with double wild-type cancers (dWT; i.e., BRAF and KRAS wild-type) had a highly favourable survival with 5-year CSS of 93% (95% CI 84-100%), while patients with cancers harbouring mutations in either BRAF or KRAS, had 5-year CSS of 76% (95% CI 67-85%). In the subgroup of stage II patients with dWT cancers no cancer-specific deaths were observed. On multivariate analysis, mutation in either BRAF or KRAS vs. dWT remained significantly prognostic. Mutations in BRAF as well as KRAS should be analyzed when considering these genes as prognostic markers in MSI colon cancers.

Less negative appendectomies due to imaging in patients with suspected appendicitis.

BACKGROUND: The optimal diagnostics and treatment of acute appendicitis continues to be a challenge. We evaluated the implementation of the guideline "diagnostics and treatment in acute appendicitis" in 2010. This guideline states that, in every patient with clinically suspected acute appendicitis, an ultrasonography or CT scan is advised to confirm the diagnosis before surgery. PATIENTS AND METHODS: We selected all consecutive patients with acute appendicitis in our hospital in the years 2008 and 2011. We compared the use of imaging and the operation results in both years. RESULTS: In 2008, 228 patients were treated for acute appendicitis. In 43 %, imaging was performed. In 2011, 238 patients were treated; in 99 % of the cases, imaging was performed. A decrease in patients with negative appendectomy was seen from 19 % in 2008 to 5 % in 2011. Financial analysis showed a reduction in costs favoring 2011. CONCLUSIONS: The increased use of pre-operative imaging in patients with suspected acute appendicitis resulted in a cost-effective way to decrease the number of patients with negative appendectomies.

Accuracy of MRI compared with ultrasound imaging and selective use of CT to discriminate simple from perforated appendicitis.

BACKGROUND: Discrimination between simple and perforated appendicitis in patients with suspected appendicitis may help to determine the therapy, timing of surgery and risk of complications. The aim of this study was to estimate the accuracy of magnetic resonance imaging (MRI) in distinguishing between simple and perforated appendicitis, and to compare MRI against ultrasound imaging with selected additional (conditional) use of computed tomography (CT). METHODS: Patients with clinically suspected appendicitis were identified prospectively at the emergency department of six hospitals. Consenting patients underwent MRI, but were managed based on findings at ultrasonography and conditional CT. Radiologists who evaluated the MRI were blinded to the results of ultrasound imaging and CT. The presence of perforated appendicitis was recorded after each evaluation. The final diagnosis was assigned by an expert panel based on perioperative data, histopathology and clinical follow-up after 3 months. RESULTS: MRI was performed in 223 of 230 included patients. Acute appendicitis was the final diagnosis in 118 of 230 patients, of whom 87 had simple and 31 perforated appendicitis. MRI correctly identified 17 of 30 patients with perforated appendicitis (sensitivity 57 (95 per cent confidence interval 39 to 73) per cent), whereas ultrasound imaging with conditional CT identified 15 of 31 (sensitivity 48 (32 to 65) per cent) (P = 0.517). All missed diagnoses of perforated appendicitis were identified as simple acute appendicitis with both imaging protocols. None of the MRI features for perforated appendicitis had a positive predictive value higher than 53 per cent. CONCLUSION: MRI is comparable to ultrasonography with conditional use of CT in identifying perforated appendicitis. However, both strategies incorrectly classify up to half of all patients with perforated appendicitis as having simple appendicitis. Triage of appendicitis based on imaging for conservative treatment is inaccurate and may be considered unsafe for decision-making. Presented to a scientific meeting of the Association of Surgeons of the Netherlands, Veldhoven, The Netherlands, May 2012; published in abstract form as Br J Surg 2012; 99(Suppl 7): S6.

Fecal microbiome analysis as a diagnostic test for diverticulitis.

Disease-specific variations in intestinal microbiome composition have been found for a number of intestinal disorders, but little is known about diverticulitis. The purpose of this study was to compare the fecal microbiota of diverticulitis patients with control subjects from a general gastroenterological practice and to investigate the feasibility of predictive diagnostics based on complex microbiota data. Thirty-one patients with computed tomography (CT)-proven left-sided uncomplicated acute diverticulitis were included and compared with 25 control subjects evaluated for a range of gastrointestinal indications. A high-throughput polymerase chain reaction (PCR)-based profiling technique (IS-pro) was performed on DNA isolates from baseline fecal samples. Differences in bacterial phylum abundance and diversity (Shannon index) of the resulting profiles were assessed by conventional statistics. Dissimilarity in microbiome composition was analyzed with principal coordinate analysis (PCoA) based on cosine distance measures. To develop a prediction model for the diagnosis of diverticulitis, we used cross-validated partial least squares discriminant analysis (PLS-DA). Firmicutes/Bacteroidetes ratios and Proteobacteria load were comparable among patients and controls (p = 0.20). The Shannon index indicated a higher diversity in diverticulitis for Proteobacteria (p < 0.00002) and all phyla combined (p = 0.002). PCoA based on Proteobacteria profiles resulted in visually separate clusters of patients and controls. The diagnostic accuracy of the cross-validated PLS-DA regression model was 84 %. The most discriminative species derived largely from the family Enterobacteriaceae. Diverticulitis patients have a higher diversity of fecal microbiota than controls from a mixed population, with the phylum Proteobacteria defining the difference. The analysis of intestinal microbiota offers a novel way to diagnose diverticulitis.

Maspin is a marker for early recurrence in primary stage III and IV colorectal cancer.

BACKGROUND: Little is known about the factors that drive metastasis formation in colorectal cancer (CRC). Here, we set out to identify genes and proteins in patients with colorectal liver metastases that correlate with early disease recurrence. Such factors may predict a propensity for metastasis in earlier stages of CRC. METHODS: Gene expression profiling and proteomics were used to identify differentially expressed genes/proteins in resected liver metastases that recurred within 6 months following liver surgery vs those that did not recur for >24 months. Expression of the identified genes/proteins in stage II (n=243) and III (n=176) tumours was analysed by immunohistochemistry on tissue microarrays. Correlation of protein levels with stage-specific outcome was assessed by uni- and multivariable analyses. RESULTS: Both gene expression profiling and proteomics identified Maspin to be differentially expressed in colorectal liver metastases with early (<6 months) and prolonged (>24 months) time to recurrence. Immunohistochemical analysis of Maspin expression on tumour sections revealed that it was an independent predictor of time to recurrence (log-rank P=0.004) and CRC-specific survival (P=0.000) in stage III CRC. High Maspin expression was also correlated with mucinous differentiation. In stage II CRC patients, high Maspin expression did not correlate with survival but was correlated with a right-sided tumour location. CONCLUSION: High Maspin expression correlates with poor outcome in CRC after spread to the local lymph nodes. Therefore, Maspin may have a stage-specific function possibly related to tumour cell dissemination and/or metastatic outgrowth.

Selective Decontamination with Oral Antibiotics in Colorectal Surgery: 90-day Reintervention Rates and Long-term Oncological Follow-up.

BACKGROUND: Oral antibiotics (OAB) in colorectal surgery have been shown to reduce surgical site infections (SSIs) and possibly anastomotic leakage. However, evidence on long-term follow-up, reintervention rates and 5-year oncological follow-up is lacking. The current study aims at elucidating this knowledge gap. METHODS: This study evaluated the long-term effectiveness of perioperative 'Selective decontamination of the digestive tract' (SDD) in colorectal cancer surgery. The primary outcome was anastomotic leakage within 90 days, secondary outcomes included infectious complications, reinterventions, readmission, hospital stay, and 5-year overall and disease-free-survival. Statistical analysis including univariate and multivariate analysis was performed to identify predictors of 90-day outcomes, and Kaplan-Meier survival analysis was used for the 5-year survival outcomes. RESULTS: In total 455 patients were analyzed, 228 participants in the SDD group and 227 in the control group. Anastomotic leakage rate was not statistically different between the SDD and control group (6.6% versus 9.7%). One or more infectious complications occurred in 15.4% of patients in the SDD group and in 28.2% in the control group (OR 0.46, 95% C.I. 0.29 - 0.73). In the SDD group 8,8% of patients required a reintervention compared to 16,3% of patients in the control group (OR 0.47, 95% C.I. 0.26 - 0.84). After multivariable analysis SDD remained significant in reducing both infectious complications and reinterventions after 90-days follow-up. There was no difference between SDD and control group in 5-year overall survival and disease-free-survival. CONCLUSION: SDD as OAB is effective in reducing 90-days postoperative infectious complications and reinterventions. As such, SDD as standard OAB in elective colorectal surgery is highly recommended.

Cost-effectiveness of selective decontamination of the digestive tract to decrease infectious complications in colorectal cancer surgery: An analysis of the SELECT trial.

INTRODUCTION: Selective decontamination of the digestive tract (SDD) is effective in reducing infectious complications in elective colorectal cancer (CRC) surgery. However, it is unclear whether SDD is cost-effective compared to standard antibiotic prophylaxis. MATERIAL & METHODS: Economic evaluation alongside multicenter randomized controlled trial, the SELECT-trial, from a healthcare perspective. Patients included underwent elective surgery for non-metastatic CRC. The intervention group received oral non-absorbable colistin, tobramycin and amphotericin B (SDD) next to standard antibiotic prophylaxis. Both groups received a single shot intravenous cefazolin and metronidazole preoperatively as standard prophylaxis. Occurrence of postoperative infectious complication in the first 30 postoperative days was extracted from medical records, Quality-Adjusted Life-Years (QALYs) based on the ED-5D-3L, and healthcare costs collected from the hospital's financial administration. RESULTS: Of the 455 patients, 228 were randomly assigned to intervention group and 227 patients to the control group. SDD significantly reduced the number of infectious complications compared to control (difference = -0.13, 95 % CI -0.05 to -0.20). No difference was found for QALYs (difference = 0.002, 95 % CI -0.002 to 0.005). Healthcare costs were statistically significantly lower in the intervention group (difference = -€1258, 95 % CI -2751 to -166). The ICER was -9872 €/infectious complication prevented and -820,380 €/QALY gained. For all willingness-to-pay thresholds, the probability that prophylactic SDD was cost-effective compared to standard prophylactic practice alone was 1.0. CONCLUSION: The addition of SDD to the standard preoperative intravenous antibiotic prophylaxis is cost-effective compared to standard prophylactic practice from a healthcare perspective and should be considered as the standard of care.

High lymph node yield is related to microsatellite instability in colon cancer.

BACKGROUND: Lymph node (LN) yield in colon cancer resection specimens is an important indicator of treatment quality and has especially in early-stage patients therapeutic implications. However, underlying disease mechanisms, such as microsatellite instability (MSI), may also influence LN yield, as MSI tumors are known to exhibit more prominent lymphocytic antitumor reactions. The aim of the present study was to investigate the association of LN yield, MSI status, and recurrence rate in colon cancer. METHODS: Clinicopathological data and tumor samples were collected from 332 stage II and III colon cancer patients. DNA was isolated and PCR-based MSI analysis performed. LN yield was defined as "high" when 10 or more LNs were retrieved and "low" in case of fewer than 10 LNs. RESULTS: Tumors with high LN yield were significantly associated with the MSI phenotype (high LN yield: 26.3% MSI tumors vs low LN yield: 15.1% MSI tumors; P=.01), mainly in stage III disease. Stage II patients with high LN yield had a lower recurrence rate compared with those with low LN yield. Patients with MSI tumors tended to develop fewer recurrences compared with those with MSS tumors, mainly in stage II disease. CONCLUSIONS: In the present study, high LN yield was associated with MSI tumors, mainly in stage III patients. Besides adequate surgery and pathology, high LN yield is possibly a feature caused by biologic behavior of MSI tumors.

Overtreatment of sigmoid diverticulitis: plea for a less aggressive approach.

A less invasive approach to the treatment of left-sided colonic diverticulitis has emerged in the last decade. The standard of care for perforated or complicated diverticulitis evolved from a Hartmann's procedure, to resection and primary anastomosis, to treatment with antibiotics and percutaneous drainage in a carefully selected (Hinchey grade 2) patient subset. Recently, laparoscopic lavage emerged as a promising less invasive treatment for selected cases of Hinchey 3 patients. Likewise, for nonperforated or uncomplicated diverticulitis the approach is becoming less aggressive with a change from intravenous antimicrobial therapy, starvation and admission, to oral antibiotics and finally to observation and outpatient treatment. This less invasive or aggressive approach is due to expanding evidence on optimal treatment and is congruent with an increasing understanding that diverticulitis comprises different disease entities with heterogeneity between patients. The disease should be targeted by specific approaches, after a meticulous assessment of the diverticulitis stage, and tailored to an individual basis. Avoidance of overtreatment has obvious benefits: less in-hospital treatment, cost reduction, diminished development of antimicrobial resistance, reduction in complication rate and side effects and presumably a better quality of life for the patient. In conclusion, one might say we have overtreated the majority of diverticulitis patients for decades. More research is needed to explain the pathogenesis and multifactorial etiology and in the near future hopefully several unanswered questions regarding the optimal management of patients with different stages of diverticulitis will be answered by various ongoing trials.