Association of modified textbook outcome and overall survival after surgery for colorectal liver metastases: A nationwide analysis.

BACKGROUND: Textbook outcome (TO) represents a multidimensional quality measurement, encompassing the desirable short-term outcomes following surgery. This study aimed to investigate whether achieving TO after resection of colorectal liver metastases (CRLM) surgery is related to better overall survival (OS) in a national cohort. METHOD: Data was retrieved from the Dutch Hepato Biliary Audit. A modified definition of TO (mTO) was used because readmissions were only recorded from 2019. mTO was achieved when no severe postoperative complications, mortality, prolonged length of hospital stay, occurred and when adequate surgical resection margins were obtained. To compare outcomes of patients with and without mTO and reduce baseline differences between both groups propensity score matching (PSM) was used for patients operated on between 2014 and 2018. RESULTS: Out of 6525 eligible patients, 81 % achieved mTO. For the cohort between 2014 and 2018, those achieving mTO had a 5-year OS of 46.7 % (CI 44.8-48.6) while non-mTO patients had a 5-year OS of 33.7 % (CI 29.8-38.2), p < 0.001. Not achieving mTO was associated with a worse OS (aHR 1.34 (95 % CI 1.17-1.53), p < 0.001. Median follow-up was 76 months., PSM assigned 519 patients to each group. In the PSM cohort patients achieving mTO, 5-year OS was 43.6 % (95 % CI 39.2-48.5) compared to 36.4 % (95 % CI 31.9-41.2) in patients who did not achieve mTO, p = 0.006. CONCLUSION: Achieving mTO is associated with improved long-term survival. This emphasizes the importance of optimising perioperative care and reducing postoperative complications in surgical treatment of CRLM.

MRI in addition to CT in patients scheduled for local therapy of colorectal liver metastases (CAMINO): an international, multicentre, prospective, diagnostic accuracy trial.

BACKGROUND: Guidelines are inconclusive on whether contrast-enhanced MRI using gadoxetic acid and diffusion-weighted imaging should be added routinely to CT in the investigation of patients with colorectal liver metastases who are scheduled for curative liver resection or thermal ablation, or both. Although contrast-enhanced MRI is reportedly superior than contrast-enhanced CT in the detection and characterisation of colorectal liver metastases, its effect on clinical patient management is unknown. We aimed to assess the clinical effect of an additional liver contrast-enhanced MRI on local treatment plan in patients with colorectal liver metastases amenable to local treatment, based on contrast-enhanced CT. METHODS: We did an international, multicentre, prospective, incremental diagnostic accuracy trial in 14 liver surgery centres in the Netherlands, Belgium, Norway, and Italy. Participants were aged 18 years or older with histological proof of colorectal cancer, a WHO performance status score of 0-4, and primary or recurrent colorectal liver metastases, who were scheduled for local therapy based on contrast-enhanced CT. All patients had contrast-enhanced CT and liver contrast-enhanced MRI including diffusion-weighted imaging and gadoxetic acid as a contrast agent before undergoing local therapy. The primary outcome was change in the local clinical treatment plan (decided by the individual clinics) on the basis of liver contrast-enhanced MRI findings, analysed in the intention-to-image population. The minimal clinically important difference in the proportion of patients who would have change in their local treatment plan due to an additional liver contrast-enhanced MRI was 10%. This study is closed and registered in the Netherlands Trial Register, NL8039. FINDINGS: Between Dec 17, 2019, and July 31, 2021, 325 patients with colorectal liver metastases were assessed for eligibility. 298 patients were enrolled and included in the intention-to-treat population, including 177 males (59%) and 121 females (41%) with planned local therapy based on contrast-enhanced CT. A change in the local treatment plan based on liver contrast-enhanced MRI findings was observed in 92 (31%; 95% CI 26-36) of 298 patients. Changes were made for 40 patients (13%) requiring more extensive local therapy, 11 patients (4%) requiring less extensive local therapy, and 34 patients (11%) in whom the indication for curative-intent local therapy was revoked, including 26 patients (9%) with too extensive disease and eight patients (3%) with benign lesions on liver contrast-enhanced MRI (confirmed by a median follow-up of 21·0 months [IQR 17·5-24·0]). INTERPRETATION: Liver contrast-enhanced MRI should be considered in all patients scheduled for local treatment for colorectal liver metastases on the basis of contrast-enhanced CT imaging. FUNDING: The Dutch Cancer Society and Bayer AG - Pharmaceuticals.

Two Days Versus Five Days of Postoperative Antibiotics for Complex Appendicitis: Cost Analysis of a Randomized, Noninferiority Trial.

OBJECTIVE: To compare costs for 2 days versus 5 days of postoperative antibiotics within the antibiotics after an aPPendectomy In Complex appendicitis trial.Background:Recent studies suggest that restrictive antibiotic use leads to a significant reduction in hospital stays without compromising patient safety. Its potential effect on societal costs remains underexplored. METHODS: This was a pragmatic, open-label, multicenter clinical trial powered for noninferiority. Patients with complex appendicitis (age ≥ 8 years) were randomly allocated to 2 days or 5 days of intravenous antibiotics after appendectomy. Patient inclusion lasted from June 2017 to June 2021 in 15 Dutch hospitals. The final follow-up was on September 1, 2021. The primary trial endpoint was a composite endpoint of infectious complications and mortality within 90 days. In the present study, the main outcome measures were overall societal costs (comprising direct health care costs and costs related to productivity loss) and cost-effectiveness. Direct health care costs were recorded based on data in the electronic patient files, complemented by a telephone follow-up at 90 days. In addition, data on loss of productivity were acquired through the validated Productivity Cost Questionnaire at 4 weeks after surgery. Cost estimates were based on prices for the year 2019. RESULTS: In total, 1005 patients were evaluated in the "intention-to-treat" analysis: 502 patients were allocated to the 2-day group and 503 to the 5-day group. The mean difference in overall societal costs was - €625 (95% CI: -€ 958 to -€ 278) to the advantage of the 2-day group. This difference was largely explained by reduced hospital stay. Productivity losses were similar between the study groups. Restricting postoperative antibiotics to 2 days was cost-effective, with estimated cost savings of €31,117 per additional infectious complication. CONCLUSIONS: Two days of postoperative antibiotics for complex appendicitis results in a statistically significant and relevant cost reduction, as compared with 5 days. Findings apply to laparoscopic appendectomy in a well-resourced health care setting.

Limited wedge resection for T1 colon cancer (LIMERIC-II trial) - rationale and study protocol of a prospective multicenter clinical trial.

BACKGROUND: The sole presence of deep submucosal invasion is shown to be associated with a limited risk of lymph node metastasis. This justifies a local excision of suspected deep submucosal invasive colon carcinomas (T1 CCs) as a first step treatment strategy. Recently Colonoscopy-Assisted Laparoscopic Wedge Resection (CAL-WR) has been shown to be able to resect pT1 CRCs with a high R0 resection rate, but the long term outcomes are lacking. The aim of this study is to evaluate the safety, effectiveness and long-term oncological outcomes of CAL-WR as primary treatment for patients with suspected superficial and also deeply-invasive T1 CCs. METHODS: In this prospective multicenter clinical trial, patients with a macroscopic and/or histologically suspected T1 CCs will receive CAL-WR as primary treatment in order to prevent unnecessary major surgery for low-risk T1 CCs. To make a CAL-WR technically feasible, the tumor may not include > 50% of the circumference and has to be localized at least 25 cm proximal from the anus. Also, there should be sufficient distance to the ileocecal valve to place a linear stapler. Before inclusion, all eligible patients will be assessed by an expert panel to confirm suspicion of T1 CC, estimate invasion depth and subsequent advise which local resection techniques are possible for removal of the lesion. The primary outcome of this study is the proportion of patients with pT1 CC that is curatively treated with CAL-WR only and in whom thus organ-preservation could be achieved. Secondary outcomes are 1) CAL-WR's technical success and R0 resection rate for T1 CC, 2) procedure-related morbidity and mortality, 3) 5-year overall and disease free survival, 4) 3-year metastasis free survival, 5) procedure-related costs and 6) impact on quality of life. A sample size of 143 patients was calculated. DISCUSSION: CAL-WR is a full-thickness local resection technique that could also be effective in removing pT1 colon cancer. With the lack of current endoscopic local resection techniques for > 15 mm pT1 CCs with deep submucosal invasion, CAL-WR could fill the gap between endoscopy and major oncologic surgery. The present study is the first to provide insight in the long-term oncological outcomes of CAL-WR. TRIAL REGISTRATION: CCMO register (ToetsingOnline), NL81497.075.22, protocol version 2.3 (October 2022).

Survival of patients with colorectal liver metastases treated with and without preoperative chemotherapy: Nationwide propensity score-matched study.

INTRODUCTION: Routine treatment with preoperative systemic chemotherapy (CTx) in patients with colorectal liver metastases (CRLM) remains controversial due to lack of consistent evidence demonstrating associated survival benefits. This study aimed to determine the effect of preoperative CTx on overall survival (OS) compared to surgery alone and to assess hospital and oncological network variation in 5-year OS. METHODS: This was a population-based study of all patients who underwent liver resection for CRLM between 2014 and 2017 in the Netherlands. After 1:1 propensity score matching (PSM), OS was compared between patients treated with and without preoperative CTx. Hospital and oncological network variation in 5-year OS corrected for case-mix factors was calculated using an observed/expected ratio. RESULTS: Of 2820 patients included, 852 (30.2%) and 1968 (69.8%) patients were treated with preoperative CTx and surgery alone, respectively. After PSM, 537 patients remained in each group, median number of CRLM; 3 [IQR 2-4], median size of CRLM; 28 mm [IQR 18-44], synchronous CLRM (71.1%). Median follow-up was 80.8 months. Five-year OS rates after PSM for patients treated with and without preoperative chemotherapy were 40.2% versus 38.3% (log-rank P = 0.734). After stratification for low, medium, and high tumour burden based on the tumour burden score (TBS) OS was similar for preoperative chemotherapy vs. surgery alone (log-rank P = 0.486, P = 0.914, and P = 0.744, respectively). After correction for non-modifiable patient and tumour characteristics, no relevant hospital or oncological network variation in five-year OS was observed. CONCLUSION: In patients eligible for surgical resection, preoperative chemotherapy does not provide an overall survival benefit compared to surgery alone.

Evaluation of National Surgical Practice for Lateral Lymph Nodes in Rectal Cancer in an Untrained Setting.

BACKGROUND: Involved lateral lymph nodes (LLNs) have been associated with increased local recurrence (LR) and ipsi-lateral LR (LLR) rates. However, consensus regarding the indication and type of surgical treatment for suspicious LLNs is lacking. This study evaluated the surgical treatment of LLNs in an untrained setting at a national level. METHODS: Patients who underwent additional LLN surgery were selected from a national cross-sectional cohort study regarding patients undergoing rectal cancer surgery in 69 Dutch hospitals in 2016. LLN surgery consisted of either 'node-picking' (the removal of an individual LLN) or 'partial regional node dissection' (PRND; an incomplete resection of the LLN area). For all patients with primarily enlarged (≥7 mm) LLNs, those undergoing rectal surgery with an additional LLN procedure were compared to those  undergoing only rectal resection. RESULTS: Out of 3057 patients, 64 underwent additional LLN surgery, with 4-year LR and LLR rates of 26% and 15%, respectively. Forty-eight patients (75%) had enlarged LLNs, with corresponding recurrence rates of 26% and 19%, respectively. Node-picking (n = 40) resulted in a 20% 4-year LLR, and a 14% LLR after PRND (n = 8; p = 0.677). Multivariable analysis of 158 patients with enlarged LLNs undergoing additional LLN surgery (n = 48) or rectal resection alone (n = 110) showed no significant association of LLN surgery with 4-year LR or LLR, but suggested higher recurrence risks after LLN surgery (LR: hazard ratio [HR] 1.5, 95% confidence interval [CI] 0.7-3.2, p = 0.264; LLR: HR 1.9, 95% CI 0.2-2.5, p = 0.874). CONCLUSION: Evaluation of Dutch practice in 2016 revealed that approximately one-third of patients with primarily enlarged LLNs underwent surgical treatment, mostly consisting of node-picking. Recurrence rates were not significantly affected by LLN surgery, but did suggest worse outcomes. Outcomes of LLN surgery after adequate training requires further research.

Practice variation and outcomes of minimally invasive minor liver resections in patients with colorectal liver metastases: a population-based study.

INTRODUCTION: In 2017, the Southampton guideline stated that minimally invasive liver resections (MILR) should considered standard practice for minor liver resections. This study aimed to assess recent implementation rates of minor MILR, factors associated with performing MILR, hospital variation, and outcomes in patients with colorectal liver metastases (CRLM). METHODS: This population-based study included all patients who underwent minor liver resection for CRLM in the Netherlands between 2014 and 2021. Factors associated with MILR and nationwide hospital variation were assessed using multilevel multivariable logistic regression. Propensity-score matching (PSM) was applied to compare outcomes between minor MILR and minor open liver resections. Overall survival (OS) was assessed with Kaplan-Meier analysis on patients operated until 2018. RESULTS: Of 4,488 patients included, 1,695 (37.8%) underwent MILR. PSM resulted in 1,338 patients in each group. Implementation of MILR increased to 51.2% in 2021. Factors associated with not performing MILR included treatment with preoperative chemotherapy (aOR 0.61 CI:0.50-0.75, p < 0.001), treatment in a tertiary referral hospital (aOR 0.57 CI:0.50-0.67, p < 0.001), and larger diameter and number of CRLM. Significant hospital variation was observed in use of MILR (7.5% to 93.0%). After case-mix correction, six hospitals performed fewer, and six hospitals performed more MILRs than expected. In the PSM cohort, MILR was associated with a decrease in blood loss (aOR 0.99 CI:0.99-0.99, p < 0.01), cardiac complications (aOR 0.29, CI:0.10-0.70, p = 0.009), IC admissions (aOR 0.66, CI:0.50-0.89, p = 0.005), and shorter hospital stay (aOR CI:0.94-0.99, p < 0.01). Five-year OS rates for MILR and OLR were 53.7% versus 48.6%, p = 0.21. CONCLUSION: Although uptake of MILR is increasing in the Netherlands, significant hospital variation remains. MILR benefits short-term outcomes, while overall survival is comparable to open liver surgery.

2 days versus 5 days of postoperative antibiotics for complex appendicitis: a pragmatic, open-label, multicentre, non-inferiority randomised trial.

BACKGROUND: The appropriate duration of postoperative antibiotics for complex appendicitis is unclear. The increasing global threat of antimicrobial resistance warrants restrictive antibiotic use, which could also reduce side-effects, length of hospital stay, and costs. METHODS: In this pragmatic, open-label, non-inferiority trial in 15 hospitals in the Netherlands, patients with complex appendicitis (aged ≥8 years) were randomly assigned (1:1) to receive 2 days or 5 days of intravenous antibiotics after appendicectomy. Randomisation was stratified by centre, and treating physicians and patients were not masked to treatment allocation. The primary endpoint was a composite endpoint of infectious complications and mortality within 90 days. The main outcome was the absolute risk difference (95% CI) in the primary endpoint, adjusted for age and severity of appendicitis, with a non-inferiority margin of 7·5%. Outcome assessment was based on electronic patient records and a telephone consultation 90 days after appendicectomy. Efficacy was analysed in the intention-to-treat and per-protocol populations. Safety outcomes were analysed in the intention-to-treat population. This trial was registered with the Netherlands Trial Register, NL5946. FINDINGS: Between April 12, 2017, and June 3, 2021, 13 267 patients were screened and 1066 were randomly assigned, 533 to each group. 31 were excluded from intention-to-treat analysis of the 2-day group and 30 from the 5-day group owing to errors in recruitment or consent. Appendicectomy was done laparoscopically in 955 (95%) of 1005 patients. The telephone follow-up was completed in 664 (66%) of 1005 patients. The primary endpoint occurred in 51 (10%) of 502 patients analysed in the 2-day group and 41 (8%) of 503 patients analysed in the 5-day group (adjusted absolute risk difference 2·0%, 95% CI -1·6 to 5·6). Rates of complications and re-interventions were similar between trial groups. Fewer patients had adverse effects of antibiotics in the 2-day group (45 [9%] of 502 patients) than in the 5-day group (112 [22%] of 503 patients; odds ratio [OR] 0·344, 95% CI 0·237 to 0·498). Re-admission to hospital was more frequent in the 2-day group (58 [12%] of 502 patients) than in the 5-day group (29 [6%] of 503 patients; OR 2·135, 1·342 to 3·396). There were no treatment-related deaths. INTERPRETATION: 2 days of postoperative intravenous antibiotics for complex appendicitis is non-inferior to 5 days in terms of infectious complications and mortality within 90 days, based on a non-inferiority margin of 7·5%. These findings apply to laparoscopic appendicectomy conducted in a well resourced health-care setting. Adopting this strategy will reduce adverse effects of antibiotics and length of hospital stay. FUNDING: The Netherlands Organization for Health Research and Development.

GITR Ligation Improves Anti-PD1-Mediated Restoration of Human MMR-Proficient Colorectal Carcinoma Tumor-Derived T Cells.

BACKGROUND & AIMS: In contrast to mismatch repair deficient colorectal carcinoma (CRC), MMR proficient (pMMR) CRC does not respond to immune checkpoint blockade. We studied immune checkpoint stimulation via glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR) on ex vivo functionality of human tumor-infiltrating lymphocytes (TIL) isolated from pMMR primary CRC and liver metastases (CRLM). METHODS: Using lymphocytes from resected tumor, adjacent tissues, and peripheral blood mononuclear cells (PBMC) of 132 pMMR primary CRC or CRLM patients, we determined GITR expression and the in vitro T-cell agonistic activity of recombinant GITR ligation. RESULTS: Here, we show that GITR was overexpressed on TIL when compared with other stimulatory immune checkpoints (4-1BB, OX40). Its expression was enhanced in TIL compared with PBMC and adjacent tissues. Among CD4+ TIL, GITR expression was primarily expressed by CD45RA- FoxP3hi activated regulatory T cells. Within CD8+ TIL, GITR was predominantly expressed on functionally exhausted and putative tumor-reactive CD103+ CD39+ TIL. Strikingly, recombinant GITRL reinvigorated ex vivo TIL responses by significantly enhancing CD4+ and CD8+ TIL numbers. Dual treatment with GITRL and nivolumab (anti-PD1) enhanced CD8+ TIL expansion compared with GITRL monotherapy. Moreover, GITRL/anti-PD1 dual therapy further improved anti-PD1-mediated reinvigoration of interferon gamma secretion by exhausted CD8 TIL from primary CRC. CONCLUSIONS: GITR is overexpressed on CD4+ and CD8+ TIL from pMMR CRC and CRLM. Agonistic targeting of GITR enhances ex vivo human TIL functionality and may therefore be a promising approach for novel monotherapy or combined immunotherapies in primary pMRR CRC and CRLM.

Multicenter cohort study on the presentation and treatment of acute appendicitis during the COVID-19 pandemic.

PURPOSE: Current studies have demonstrated conflicting results regarding surgical care for acute appendicitis during the COVID-19 pandemic. This study aimed to assess trends in diagnosis as well as treatment of acute appendicitis in the Netherlands during the first and second COVID-19 infection wave. METHODS: All consecutive patients that had an appendectomy for acute appendicitis in nine hospitals from January 2019 to December 2020 were included. The primary outcome was the number of appendectomies for acute appendicitis. Secondary outcomes included time between onset of symptoms and hospital admission, proportion of complex appendicitis, postoperative length of stay and postoperative infectious complications. Outcomes were compared between the pre-COVID group and COVID group. RESULTS: A total of 4401 patients were included. The mean weekly rate of appendectomies during the COVID period was 44.0, compared to 40.9 in the pre-COVID period. The proportion of patients with complex appendicitis and mean postoperative length of stay in days were similar in the pre-COVID and COVID group (respectively 35.5% vs 36.8%, p = 0.36 and 2.0 ± 2.2 vs 2.0 ± 2.6, p = 0.93). There were no differences in postoperative infectious complications. A computed tomography scan was used more frequently as a diagnostic tool after the onset of COVID-19 compared to pre-COVID (13.8% vs 9.8%, p < 0.001, respectively). CONCLUSION: No differences were observed in number of appendectomies, proportion of complex appendicitis, postoperative length of stay or postoperative infectious complications before and during the COVID-19 pandemic. A CT scan was used more frequently during the COVID-19 pandemic.

Colonoscopic-Assisted Laparoscopic Wedge Resection for Colonic Lesions: A Prospective Multicenter Cohort Study (LIMERIC-Study).

OBJECTIVE: The aim of this study was to evaluate the safety and efficacy of a modified CAL-WR. SUMMARY BACKGROUND DATA: The use of segmental colectomy in patients with endoscopically unresectable colonic lesions results in significant morbidity and mortality. CAL-WR is an alternative procedure that may reduce morbidity. METHODS: This prospective multicenter study was performed in 13 Dutch hospitals between January 2017 and December 2019. Inclusion criteria were (1) colonic lesions inaccessible using current endoscopic resection techniques (judged by an expert panel), (2) non-lifting residual/recurrent adenomatous tissue after previous polypectomy or (3) an undetermined resection margin after endoscopic removal of a low-risk pathological T1 (pT1) colon carcinoma. Thirty-day morbidity, technical success rate and radicality were evaluated. RESULTS: Of the 118 patients included (56% male, mean age 66 years, standard deviation ± 8 years), 66 (56%) had complex lesions unsuitable for endoscopic removal, 34 (29%) had non-lifting residual/recurrent adenoma after previous polypectomy and 18 (15%) had uncertain resection margins after polypectomy of a pT1 colon carcinoma. CAL-WR was technically successful in 93% and R0 resection was achieved in 91% of patients. Minor complications (Clavien-Dindo i-ii) were noted in 7 patients (6%) and an additional oncologic segmental resection was performed in 12 cases (11%). Residual tissue at the scar was observed in 5% of patients during endoscopic follow-up. CONCLUSIONS: CAL-WR is an effective, organ-preserving approach that results in minor complications and circumvents the need for major surgery. CAL-WR, therefore, deserves consideration when endoscopic excision of circumscribed lesions is impossible or incomplete.

Nationwide oncological networks for resection of colorectal liver metastases in the Netherlands: Differences and postoperative outcomes.

INTRODUCTION: Widespread differences in patient demographics and disease burden between hospitals for resection of colorectal liver metastases (CRLM) have been described. In the Netherlands, networks consisting of at least one tertiary referral centre and several regional hospitals have been established to optimize treatment and outcomes. The aim of this study was to assess variation in case-mix, and outcomes between these networks. METHODS: This was a population-based study including all patients who underwent CRLM resection in the Netherlands between 2014 and 2019. Variation in case-mix and outcomes between seven networks covering the whole country was evaluated. Differences in case-mix, expected 30-day major morbidity (Clavien-Dindo ≥3a) and 30-day mortality between networks were assessed. RESULTS: In total 5383 patients were included. Thirty-day major morbidity was 5.7% and 30-day mortality was 1.5%. Significant differences between networks were observed for Charlson Comorbidity Index, ASA 3+, previous liver resection, liver disease, preoperative MRI, preoperative chemotherapy, ≥3 CRLM, diameter of largest CRLM ≥55 mm, major resection, combined resection and ablation, rectal primary tumour, bilobar and extrahepatic disease. Uncorrected 30-day major morbidity ranged between 3.3% and 13.1% for hospitals, 30-day mortality ranged between 0.0% and 4.5%. Uncorrected 30-day major morbidity ranged between 4.4% and 6.0% for networks, 30-day mortality ranged between 0.0% and 2.5%. No negative outliers were observed after case-mix correction. CONCLUSION: Variation in case-mix and outcomes are considerably smaller on a network level as compared to a hospital level. Therefore, auditing is more meaningful at a network level and collaboration of hospitals within networks should be pursued.

Case-mix adjustment to compare nationwide hospital performances after resection of colorectal liver metastases.

BACKGROUND: Differences in patient demographics and disease burden can influence comparison of hospital performances. This study aimed to provide a case-mix model to compare short-term postoperative outcomes for patients undergoing liver resection for colorectal liver metastases (CRLM). METHODS: This retrospective, population-based study included all patients who underwent liver resection for CRLM between 2014 and 2018 in the Netherlands. Variation in case-mix variables between hospitals and influence on postoperative outcomes was assessed using multivariable logistic regression. Primary outcomes were 30-day major morbidity and 30-day mortality. Validation of results was performed on the data from 2019. RESULTS: In total, 4639 patients were included in 28 hospitals. Major morbidity was 6.2% and mortality was 1.4%. Uncorrected major morbidity ranged from 3.3% to 13.7% and mortality ranged from 0.0% to 5.0%. between hospitals. Significant differences between hospitals were observed for age higher than 80 (0.0%-17.1%, p < 0.001), ASA 3 or higher (3.3%-36.3%, p < 0.001), histopathological parenchymal liver disease (0.0%-47.1%, p < 0.001), history of liver resection (8.1%-36.3%, p < 0.001), major liver resection (6.7%-38.0%, p < 0.001) and synchronous metastases (35.5%-62.1%, p < 0.001). Expected 30-day major morbidity between hospitals ranged from 6.4% to 11.9% and expected 30-day mortality ranged from 0.6% to 2.9%. After case-mix correction no significant outliers concerning major morbidity and mortality remained. Validation on patients who underwent liver resection for CRLM in 2019 affirmed these outcomes. CONCLUSION: Case-mix adjustment is a prerequisite to allow for institutional comparison of short-term postoperative outcomes after liver resection for CRLM.

Implementation and outcome of minor and major minimally invasive liver surgery in the Netherlands.

BACKGROUND: While most of the evidence on minimally invasive liver surgery (MILS) is derived from expert centers, nationwide outcomes remain underreported. This study aimed to evaluate the implementation and outcome of MILS on a nationwide scale. METHODS: Electronic patient files were reviewed in all Dutch liver surgery centers and all patients undergoing MILS between 2011 and 2016 were selected. Operative outcomes were stratified based on extent of the resection and annual MILS volume. RESULTS: Overall, 6951 liver resections were included, with a median annual volume of 50 resections per center. The overall use of MILS was 13% (n = 916), which varied from 3% to 36% (P < 0.001) between centers. The nationwide use of MILS increased from 6% in 2011 to 23% in 2016 (P < 0.001). Outcomes of minor MILS were comparable with international studies (conversion 0-13%, mortality <1%). In centers which performed ≥20 MILS annually, major MILS was associated with less conversions (14 (11%) versus 41 (30%), P < 0.001), shorter operating time (184 (117-239) versus 200 (139-308) minutes, P = 0.010), and less overall complications (37 (30%) versus 58 (42%), P = 0.040). CONCLUSION: The nationwide use of MILS is increasing, although large variation remains between centers. Outcomes of major MILS are better in centers with higher volumes.

Minimally Invasive versus Open Approach for Right-Sided Colectomy: A Study in 12,006 Patients from the Dutch Surgical Colorectal Audit.

BACKGROUND: There is ongoing debate whether laparoscopic right colectomy is superior to open surgery. The purpose of this study was to address this issue and arrive at a consensus using data from a national database. METHODS: Patients who underwent elective open or laparoscopic right colectomy for colorectal cancer during the period 2009-2013 were identified from the Dutch Surgical Colorectal Audit. Complications that occurred within 30 days after surgery and 30-day mortality rates were calculated and compared between open and laparoscopic resection. RESULTS: In total, 12,006 patients underwent elective open or laparoscopic surgery for right-sided colorectal cancer. Of these, 6,683 (55.7%) underwent open resection and 5,323 (44.3%) underwent laparoscopic resection. Complications occurred within 30 days after surgery in the laparoscopic group in 26.1% of patients and in 32.1% of patients in the open group (p < 0.001). Thirty-day mortality was also significantly lower in the laparoscopic group (2.2 vs. 3.6% p < 0.001). CONCLUSION: In this non-randomized, descriptive study conducted in the Netherlands, open right colectomy seems to have a higher risk for complications and mortality as compared to laparoscopic right colectomy, even after correction for confounding factors.

McKittrick Wheelock Syndrome Treated by Transanal Minimally Invasive Surgery: A Single-Center Experience and Review of the Literature.

INTRODUCTION: McKittrick Wheelock Syndrome (MKWS) is a rare syndrome characterized by secretory diarrhea, dehydration, prerenal acute kidney injury, and severe electrolyte abnormalities caused by a large hypersecretory villous adenoma located in the rectum or rectosigmoid junction. Transabdominal (laparoscopic) procedures are the most described procedures in the treatment of MKWS. We report an alternative surgical approach, transanal minimally invasive surgery (TAMIS), to solve this syndrome. MATERIALS AND METHODS: All patients who underwent transanal endoscopic microsurgery or TAMIS were included in a prospectively collected database in our center. Between 1996 and 2015, 3 patients were found to have MKWS and treated by TAMIS. Demographics, characteristics of the adenoma, surgery-related data, and outcome were analyzed. RESULTS: The first patient had a villous adenoma 0-12 cm from the anal verge. After TAMIS, she complained of a stenosis that was successfully treated by dilatation. The second patient had an impressive bulky tumor in the rectum. An endoscopic mucosal resection was attempted twice, but incompletely. Pathology analysis showed villous adenoma with high-grade dysplasia and intramucosal carcinoma. One year after TAMIS, a recurrence was detected and treated by an abdominal-perineal resection. A TAMIS was performed in the third patient because of a giant villous circular adenoma, but because of high mucus and fluid production, no proper overview could be obtained. Together with opening of the peritoneum, this prompted us to convert to a laparoscopic Hartmann procedure. Besides this technical difficulty, the patient recovered uneventful. CONCLUSIONS: MKWS is a rare syndrome and missed diagnosis could result in life-threatening situations. Different endoscopic and surgical treatments are described to solve this syndrome. TAMIS should be considered as a rectum-preserving surgical treatment option for such extensive adenomas.

Incisional Negative-Pressure Wound Therapy for Perineal Wounds After Abdominoperineal Resection for Rectal Cancer, a Pilot Study.

Objective: Abdominoperineal resection (APR) is associated with high incidence of surgical wound infections. The use of incisional negative-pressure wound therapy (iNPWT) is known to reduce wound infections for several surgical indications. The aim of this pilot study was to investigate the potential of a new portable negative-pressure therapy device on perineal wound healing in patients undergoing APR. Approach: A new single-use incisional negative-pressure therapy device was applied in 10 patients. A negative pressure of -80 mmHg was continued for 7 days postsurgery. Incidence of wound complications and time to wound healing were compared with a historical control group of 10 patients undergoing APR in 2014, treated with conventional wound care. Results: Patient characteristics were comparable in both groups. Mean 1.6 dressings were used per patient. A wound complication was diagnosed in seven patients versus six in the control group. Wound infections were diagnosed median 11.5 days after surgery, compared with 10.5 days in the control group. Duration of wound healing was shorter in the study group (median 8.5 weeks vs. 13 weeks). Innovation: This is the first study to report on the use of this iNPWT device for patients who underwent APR for rectal cancer. Conclusion: In this study, iNPWT did not reduce wound complications. Wound infections occurred slightly later and seemed to have a less severe clinical course. After treatment with iNPWT, the duration of wound healing was shorter.