Risk Factors for Persistent Postoperative Opioid Use After Surgery for IBD: An Observational Cohort Study.

BACKGROUND: Patients with IBD are at increased risk of persistent opioid use, wherein surgery plays an important role. OBJECTIVE: Identify risk factors for persistent postoperative opioid use in patients with IBD undergoing GI surgery and describe in-hospital postoperative opioid treatment. DESIGN: This was a retrospective observational cohort study. ORs for persistent postoperative opioid use were calculated using preoperative and in-hospital characteristics, and in-hospital opioid use was described using oral morphine equivalents. SETTING: This study was conducted at a university hospital with a dedicated IBD surgery unit. PATIENTS: Patients who underwent surgery for IBD from 2017 to 2022 were included. MAIN OUTCOME MEASURES: Our main outcome measure was persistent postoperative opioid use (1 or more opioid prescriptions filled 3-9 months postoperatively). RESULTS: We included 384 patients, of whom 36 (9.4%) had persistent postoperative opioid use, but only 11 (2.9%) of these patients were opioid naive preoperatively. We identified World Health Organization performance status >1 (OR 8.21; 95% CI, 1.19-48.68), preoperative daily opioid use (OR 12.84; 95% CI, 4.78-35.36), psychiatric comorbidity (OR 3.89; 95% CI, 1.29-11.43) and in-hospital mean daily opioid use (per 10 oral morphine equivalent increase; OR 1.22; 95% CI, 1.12-1.34) as risk factors for persistent postoperative opioid use using multivariable regression analysis. LIMITATIONS: Our observational study design and limited sample size because of it being a single-center study resulted in wide CIs. CONCLUSIONS: We identified risk factors for persistent postoperative opioid use in patients undergoing surgery for IBD. Results indicate a need for optimization of pain treatment in patients with IBD both before and after surgery. These patients might benefit from additional opioid-sparing measures. See Video Abstract. FACTORES DE RIESGO EN LA ADMINISTRACION DURADERA DE OPIOIDES EN EL POSTOPERATORIO EN CASOS DE CIRUGA POR ENFERMEDAD INFLAMATORIA INTESTINAL ESTUDIO OBSERVACIONAL DE COHORTES: ANTECEDENTES:Los pacientes con enfermedad inflamatoria intestinal (EII) tienen un mayor riesgo de recibir opioides de manera duradera, casos donde la cirugía juega un papel importante.OBJETIVO:Identificar los factores de riesgo en la administración duradera de opioides en el post-operatorio de cirugía gastrointestinal en casos de EII y describir el tratamiento intra-hospitalario con los mismos.DISEÑO:Estudio observacional retrospectivo de cohortes. La relación de probabilidades (odds ratio - OR) en la adminstracion duradera de opioides post-operatorios fué calculada utilizando las características pré-operatorias y hospitalarias, donde la administración de opioides intra-hospitalarios fué descrita con la utilización de equivalentes de morfina oral.AMBIENTE:Estudio realizado en un hospital universitario con una unidad de cirugía dedicada a la EII.PACIENTES:Se incluyeron todos los pacientes sometidos a cirugía por EII entre 2017 y 2022.PRINCIPALES MEDIDAS DE RESULTADO:Nuestra principal medida de resultado fué la administración post-operatoria duradera de opioides (≥1 receta completa de opioides entre 3 y 9 meses después de la operación).RESULTADOS:Incluimos 384 pacientes, de los cuales 36 (9,4%) recibieron opioides de manera duradera en el post-operatorio, de los cuales solamente 11 pacientes (2,9%) no habían recibido opioides antes de la operación. Identificamos el estado funcional de la OMS > 1 (OR 8,21, IC 95% 1,19-48,68), el uso diario de opioides pré-operatorios (OR 12,84, IC 95% 4,78-35,36), los casos de comorbilidad psiquiátrica (OR 3,89, IC 95% 1,29-11,43) y el uso medio diario de opioides en el hospital (por cada aumento de 10 equivalentes de morfina oral) (OR 1,22, IC del 95%: 1,12-1,34 como factores de riesgo para la administración de opioides de manera duradera en el post-operatorio mediante el análisis de regresión multivariable.LIMITACIONES:Nuestro diseño de estudio observacional y el tamaño de la muestra limitada debido a que fue un estudio en un solo centro, dando como resultado intervalos de confianza muy amplios.CONCLUSIONES:Se identificaron los factores de riesgo en la administración duradera de opioides en el post-operatorio de cirugía gastrointestinal en casos de EII. Los resultados demuestran la necesidad de optimizar el tratamiento del dolor en pacientes con EII, tanto antes como después de la cirugía. Estos pacientes podrían beneficiarse de medidas adicionales de ahorro de opioides. (Traducción-Dr. Xavier Delgadillo).

Perioperative Metformin Treatment to Reduce Postoperative Hyperglycemia After Colon Cancer Surgery: A Randomized Clinical Trial.

BACKGROUND: Surgery induces a stress response causing insulin resistance that may result in postoperative hyperglycemia. Postoperative hyperglycemia is associated with increased incidence of complications, longer hospitalization and greater mortality. OBJECTIVE: This study examined the effect of metformin treatment on the percentage of patients experiencing postoperative hyperglycemia after elective colon cancer surgery. DESIGN: This was a randomized double-blind placebo-controlled trial. SETTINGS: The study was conducted at Slagelse Hospital, Slagelse, Denmark. PATIENTS: Patients without diabetes planned for elective surgery for colon cancer were included. INTERVENTIONS: Patients received metformin 500mg three times a day or placebo for 20 days before and 10 days after surgery. MAIN OUTCOME MEASURES: Blood glucose levels were measured several times daily until the end of postoperative day two. The main outcome measures were the percentage of patients who experienced at least one blood glucose measurement above 7.7 and 10 mmol/l, respectively. Rates of complications within 30 days of surgery and Quality of recovery-15 scores were also recorded. RESULTS: Of the 48 included patients, 21 (84.0%) in the placebo group and 18 (78.3%) in the metformin group had at least one blood glucose measurement above 7.7 mmol/l (p = 0.72), and 13 (52.0%) patients in the placebo group had a measurement above 10.0 mmol/l versus 5 (21.7%) in the metformin group, (p = 0.04). No differences in complication rates or Quality of recovery-15 scores were seen. LIMITATIONS: The number of patients in the study was too low to detect a possible difference in postoperative complications. Blood glucose was measured as spot measurements instead of continuous surveillance. CONCLUSIONS: In patients without diabetes, metformin significantly reduced the percentage of patients experiencing postoperative hyperglycemia as defined as spot blood glucose measurements above 10 mmol/l after elective colon cancer surgery. See Video Abstract.

Long-Term Outcomes After Colorectal Surgery in Patients with Ulcerative Colitis-Associated Colorectal Cancer Versus Sporadic Colorectal Cancer.

BACKGROUND: Ulcerative colitis is associated with a higher risk for developing colorectal cancer. It is unknown whether this translates into a worse prognosis when malignancy occurs. The goal of this study was to compare long-term outcomes between patients with ulcerative colitis-associated colorectal cancer and sporadic colorectal cancer. METHODS: All patients who underwent surgery with curative intent for colorectal cancer in Denmark between January 2004 and June 2016 were included in the study. Patients diagnosed with ulcerative colitis were identified and matched 1:5 with patients with sporadic colorectal cancer using propensity score matching. The primary outcome was disease-free survival, with recurrence-free survival and all-cause mortality as secondary outcomes. In order to relate the results of the study to the existing literature, a systematic review with meta-analysis was conducted. RESULTS: A total of 1332 patients, 222 with ulcerative colitis and 1110 with sporadic colorectal cancer were included in the study. Disease-free survival was similar between the two groups with a hazards ratio (HR) 1.06 [95% confidence interval (CI) 0.85-1.32], as was recurrence-free survival HR 1.14 (95% CI 0.86-1.53) and all-cause mortality HR 1.15 (95% CI 0.89-1.48). The results of the systematic review identified seven other relevant studies. Meta-analysis showed a HR 1.67 (95% CI 0.61-4.56) for recurrence-free survival and HR 1.21 (95% CI 0.93-1.56) for all-cause mortality. CONCLUSIONS: There were no significant differences in long-term outcomes between ulcerative colitis-associated and sporadic colorectal cancer. However, the current results are limited by possible residual confounding and the meta-analysis by heterogeneity in confounding adjustment.

Long-term oncological outcomes in patients undergoing laparoscopic versus open surgery for colon cancer: A nationwide cohort study.

AIM: To estimate the effect of laparoscopy versus laparotomy on recurrence status in patients undergoing intended curative resection for stage I-III colon cancer using nationwide data. METHOD: A retrospective cohort study using prospectively collected nationwide quality assurance data on all patients undergoing elective, intended curative surgery for UICC stage I-III colon cancer in Denmark from 1 January 2010, through 31 December 2013. The association between laparoscopic versus open surgery and recurrence status was investigated using cause-specific hazard and subdistribution hazard models with death from any cause as a competing event. RESULTS: In total, 4369 patients undergoing elective intended curative surgery for colon cancer were included in the analysis. Overall, 3243 (74.2%) patients underwent laparoscopic surgery. During a median follow-up time of 84 months, 1191 (27.2%) patients experienced recurrence, and 1304 (29.8%) patients died. The cause-specific hazard of recurrence following laparoscopic versus open surgery was HRCS  = 1.08, 95% CI: 0.90-1.28, p = 0.422. The subdistribution hazard of recurrence following laparoscopic versus open surgery was HRSD =0.99, 95% CI: 0.84-1.16, p = 0.880. CONCLUSION: Elective laparoscopic resection for UICC stage I-III colon cancer is oncologically safe and comparable with open resection. These results confirm the external validity of previous RCTs in everyday clinical settings.

The impact of postoperative complications and delay of adjuvant chemotherapy on oncological outcomes in patients with colorectal cancer.

AIM: Postoperative complications are believed to result in poorer long-term oncological outcomes. The contribution of time to chemotherapy has not been analysed in detail. Our aim was to examine the association between postoperative complications and long-term oncological outcomes and overall survival, and the influence of delay in chemotherapy on these outcomes. METHOD: The study was a nationwide register-based observational study that included patients undergoing surgery for colorectal cancer and receiving adjuvant chemotherapy in Denmark between 2010 and 2015. Information regarding postoperative complications was obtained from the Danish Colorectal Cancer Group national clinical registry. A Cox regression model was used to estimate disease-free survival, recurrence-free survival and all-cause mortality in patients surviving for 180 days or more after surgery. RESULTS: A total of 4083 patients were included, of whom 690 had postoperative complications. Postoperative complications were associated with increased odds of delay to adjuvant chemotherapy (odds ratio 4.56, 95% CI 3.67-5.66, p < 0.0001). An unadjusted analysis revealed that patients with complications had poorer disease-free survival and recurrence-free survival and had increased all-cause mortality. In multivariate analysis, postoperative complications were not associated with poorer disease-free survival [hazard ratio (HR) 1.02, 95% CI 0.88-1.18, p = 0.80] recurrence-free survival (HR 1.05, 95% CI 0.89-1.25, p = 0.56) or all-cause mortality (HR 1.04, 95% CI 0.86-1.26, p = 0.67). CONCLUSION: This study showed no association between the occurrence of postoperative complications and long-term prognosis when adjusting for time to adjuvant chemotherapy.

Perioperative Use of Nonsteroidal Anti-inflammatory Drugs Decreases the Risk of Recurrence of Cancer After Colorectal Resection: A Cohort Study Based on Prospective Data.

BACKGROUND: Perioperative use of nonsteroidal anti-inflammatory drugs (NSAIDs) is known to reduce inflammatory response in relation to surgery. Inflammation may promote recurrence of cancer, thus inhibition by use of NSAIDs could reduce recurrence after surgery. OBJECTIVE: The aim of this study was to examine the association between perioperative use of NSAIDs and cancer recurrence, as well as disease-free survival (DFS) and mortality after colorectal cancer surgery. METHODS: This was a cohort study based on data from a prospective clinical database, electronic medical records, and nationwide registers, and included patients from six major colorectal centers in Denmark. The primary outcome was cancer recurrence, while secondary outcomes included 5-year mortality and DFS. RESULTS: Overall, 2308 patients undergoing colorectal cancer surgery between 1 January 2006 and 31 December 2009 were included. A total of 909 patients received at least 2 days of treatment with NSAIDs, of whom 702 (77.2%) received ibuprofen and 204 (22.4%) received diclofenac. Cox regression analysis adjusting for NSAIDs resulted in decreased recurrence risk (adjusted hazard ratio [HRadjusted] 0.84, 95% confidence interval [CI] 0.72-0.99; p = 0.042). Competing risk analysis confirmed the finding, with an HRadjusted of 0.76 (95% CI 0.60-0.97; p = 0.026). There was no significant effect on mortality or DFS. Sensitivity analysis of the effect of ibuprofen reported an HRadjusted of 0.83 (95% CI 0.70-1.00; p = 0.047). In restricted analyses of localized disease only (Union for International Cancer Control [UICC] I-II) and elective surgery only, no effect was found (localized: HRadjusted 0.81, 95% CI 0.62-1.06, p = 0.12; elective: HRadjusted 0.85, 95% CI 0.72-1.01, p = 0.063). CONCLUSIONS: Perioperative use of NSAIDs was associated with a reduced risk of cancer recurrence after resection for colorectal cancer. No effect on 5-year mortality or DFS was found.

Association between metformin use after surgery for colorectal cancer and oncological outcomes: A nationwide register-based study.

Colorectal cancer is one of the most common malignancies in the Western world, and even after surgical removal, there is a high recurrence rate. Metformin treatment has been associated with a reduced risk of developing cancer, but whether metformin influences the risk of recurrence is unknown. The aim of our study was to examine the association between treatment with metformin and recurrence-free, disease-free survival and all-cause mortality after surgery for colorectal cancer. The study was an observational register-based study and included 25,785 patients, of which 1,116 had medically treated diabetes and 966 started metformin treatment at some point postoperatively. Diabetes was not associated with neither disease-free (HRadjusted = 1.09, 95% CI 0.97-1.21, p = 0.15) nor recurrence-free survival (HRadjusted = 1.13, 95% CI 0.95-1.35, p = 0.17). The study found no difference in regards to disease-free or recurrence-free survival between the metformin treated group (HRRFS = 1.06, 95% CI 0.87-1.15, p = 0.57, HRDFS = 1.01, 95% CI 0.89-1.15, p = 0.85) and non-diabetic patients. Patients with diabetes had increased all-cause mortality (HRadjusted = 1.29, 95% CI 1.16-1.45, p < 0.0001). Metformin treatment did not affect all-cause mortality (HR = 1.07, 95% CI 0.94-1.22, p = 0.33) compared to non-diabetic patients. In conclusion, our study did not find an association between diabetes or metformin treatment and recurrence-free or disease-free survival after surgery for colorectal cancer. However, diagnosis of diabetes is associated with increased all-cause mortality.

Long-Term Outcomes of Robot-Assisted Surgery in Patients with Colorectal Cancer.

BACKGROUND: Robotic technology has been proven to be a safe alternative to conventional laparoscopy with regards to the peri- and postoperative clinical outcomes. Oncological outcomes have been scarcely examined. The purpose of this study was to examine the disease-free survival in relation to the two surgical approaches: robot-assisted surgery and conventional laparoscopy. In addition, all-cause mortality and recurrence-free survival were investigated. METHODS: Between January 2010 and December 2015, patients, undergoing either laparoscopic or robot-assisted elective, curative-intended surgery for colorectal cancer were included. RESULTS: A total of 9184 patients underwent surgery in the study period: 5978 patients for colon cancer and 3206 patients for rectal cancer. Among patients with colon cancer, 331 patients (5.5%) underwent robot-assisted surgery, and 449 patients (14.0%) underwent robot-assisted surgery in the rectal cancer group. In the adjusted analyses, the hazard ratio (HR) for disease-free survival, for patients with colon cancer was 0.91 [95% confidence interval (CI) 0.71-1.18]. For patients with rectal cancer, the adjusted HR was 0.83 (95% CI 0.65-1.06). No difference in all-cause mortality and recurrence-free survival were observed. CONCLUSIONS: The study demonstrated comparable rates of disease-free survival, all-cause mortality, and recurrence-free survival when comparing robot-assisted surgery with conventional laparoscopy in patients with colorectal cancer.

Statin use is not associated with improved 30-day survival in patients undergoing surgery for colorectal cancer.

PURPOSE: Besides the lipid-lowering properties, statins are thought to have anti-inflammatory effects and it has been shown that statins directly attenuate the inflammatory stress response after surgical trauma. The aim of the study was to examine the association between preoperative statin use and 30-day mortality as well as postoperative complications after curative-intended surgery for colorectal cancer. METHODS: The study was a Danish nationwide register-based observational study. A total of 29,352 patients undergoing surgery for colorectal cancer between January 1, 2003, and December 31, 2012, were included in the study. At the time of surgery, 5961 were registered as statin users. The outcomes were 30-day mortality and risk of postoperative complications. RESULTS: The adjusted hazard ratio of 30-day mortality was 0.91 (95 CI 0.80-1.04, P = 0.16) among statin users compared with the non-statin group. There was no difference between the two groups regarding the risk of infectious complications (sepsis, anastomotic leakage, pneumonia) (odds ratio 0.95, 95% CI 0.86-1.05, P = 0.31). For other postoperative complications (cardiovascular events, stroke, renal failure, respiratory insufficiency, and thromboembolic events), there was no significant difference between the two groups (odds ratio 0.89, 95% CI 0.78-1.01, P = 0.06). CONCLUSION: The study did not show an improved 30-day survival after surgery for colorectal cancer in patients treated with statins in the year preceding surgery. No overall association with the risk of postoperative complications was shown.

Metformin Increases Overall Survival in Patients with Diabetes Undergoing Surgery for Colorectal Cancer.

BACKGROUND: Emerging evidence suggests that metformin decreases the risk of developing colorectal cancer in patients with diabetes, but only few studies have examined potential survival benefits after surgery for colorectal cancer (CRC). The purpose of the study was to examine the association between diabetes and overall survival after resection for CRC. Furthermore, the association between antidiabetic medication and overall survival was examined. METHODS: Patients diagnosed with CRC between January 1, 2003 and December 31, 2012 were identified through the Danish Colorectal Cancer Group's National Clinical Database (DCCG). The Danish National Patient Register (NPR) records all hospital contacts in Denmark, and the diagnosis of diabetes was identified by combining NPR data with use of antidiabetic drugs identified through the Danish National Prescription Registry and DCCG. The Kaplan-Meier estimator and the Cox regression model adjusted for important clinical risk factors were used. RESULTS: A total of 30,493 patients were included in the study, of which 3391 were diagnosed with diabetes and 1962 were treated with metformin. The adjusted HR of all-cause mortality for the diabetes group was 1.12 (1.06-1.18, p < 0.0001) compared with the nondiabetes group. The adjusted HR was 0.85 (0.73-0.93, p = 0.03) for the metformin-treated group compared with the insulin-treated group. CONCLUSIONS: A 12 % increase in all-cause mortality among patients with CRC and diabetes was found. Treatment with metformin was associated with a 15 % decreased all-cause mortality compared with patients with insulin-treated diabetes.

Post-operative complications after colorectal cancer surgery increased with higher BMI.

INTRODUCTION: Because of conflicting evidence regarding overweight and post-operative complications, this study focused on post-operative complications and death within 30 and 90 days after curatively intended surgery for colorectal cancer and its association with BMI. METHODS: The study included all patients who had potentially curative surgery for colon or rectum cancer in Denmark from 2014 through 2018. The primary endpoint was post-operative complications within 30 days of surgery and secondary endpoints were 30- and 90-day mortality. All clinically relevant confounders were included in a multivariate analysis. RESULTS: The cohort included 14,004 patients. In the multivariate logistic regression analysis, adjusting for relevant confounders, we found the odds ratio of having a surgical complication or having both a surgical and medical complication at the same time to be rising with increasing weight class. The multivariate analysis showed the odds ratio for both 30- and 90-day mortality to be higher for underweight patients and for obesity class III patients, but the rest of the patients had no significant differences in relative risk compared with normal-weight patients. CONCLUSION: Based on our results, the risk of post-operative complications rises with increasing weight, whereas post-operative morbidity is increased only in the underweight and morbidly obese patients. FUNDING: none. TRIAL REGISTRATION: The study was approved by the Danish Data Protection Agency (REG-008-2020).

Risk Prediction for Complications in Inflammatory Bowel Disease Surgery: External Validation of the American College of Surgeons' National Surgical Quality Improvement Program Surgical Risk Calculator.

BACKGROUND AND AIMS: Many patients with inflammatory bowel disease [IBD] require surgery during their disease course. Having individual risk predictions available prior to surgery could aid in better informed decision making for personalised treatment trajectories in IBD surgery. The American College of Surgeons National Surgical Quality Improvement Program [ACS NSQIP] has developed a surgical risk calculator that calculates risks for postoperative outcomes using 20 patient and surgical predictors. We aimed to validate the calculator for IBD surgery to determine its accuracy in this patient cohort. METHODS: Predicted risks were calculated for patients operated for IBD between December 2017 and January 2022 at two tertiary centres and compared with actual outcomes within 30 postoperative days. Predictive performance was assessed for several postoperative complications, using metrics for discrimination and calibration. RESULTS: Risks were calculated for 508 patient trajectories undergoing surgery for IBD. Incidence of any complication, serious complications, reoperation, and readmission were 32.1%, 21.1%, 15.2%, and 18.3%, respectively. Of 212 patients with an anastomosis, 19 experienced leakage [9.0%]. Discriminative performance and calibration were modest. Risk prediction for any complication, serious complication, reoperation, readmission, and anastomotic leakage had a c statistic of 0.605 (95% confidence interval [CI] 0.534-0.640), 0.623 [95% CI 0.558-0.688], 0.590 [95% CI 0.513-0.668], 0.621 [95% CI 0.557-0.685], and 0.574 [95% CI 0.396-0.751], respectively, and a Brier score of 0.240, 0.166, 0.138, 0.152, and 0.113, respectively. CONCLUSIONS: The accuracy of risks calculated by the ACS NSQIP Surgical Risk Calculator was deemed insufficient for patients undergoing surgery for IBD, generally underestimating postoperative risks. Recalibration or additional variables could be necessary to predict risks in this cohort.

Anaesthetic technique and outcomes after colorectal cancer surgery.

INTRODUCTION: Previous studies have suggested that choice of anaesthesia can affect long-term outcome. In this study, the association between type of anaesthesia and outcomes in terms of survival, recurrence, post-operative complications and recovery after surgery for colorectal cancer was investigated in an Enhanced Recovery after Surgery (ERAS) setting. METHODS: This was a retrospective study including patients undergoing elective curative-intended surgery for colorectal cancer between April 2013 and May 2015 at Zealand University Hospital, Denmark. Patients were stratified by anaesthetic technique. The primary outcome was cancer recurrence. Cox regression analyses were used for time-to-event variables; recurrence, disease-free survival, mortality, length of hospitalisation and time to bowel movement. Odds ratios for post-operative complications and time to discharge were estimated using logistic regression. RESULTS: A total of 534 patients were included, 51 were exposed to inhalational anaesthesia and 483 had total intravenous anaesthesia. We found no statistically significant difference in recurrence (hazard ratio (HR) = 0.70; 95% confidence interval (CI): 0.21-1.68; p = 0.421). Patients in the inhalational aneasthesia group had a significantly lower chance of discharge per post-operative day (HR = 0.66; 95% CI: 0.48-0.91; p = 0.012). The same was seen for time to bowel movement (HR = 0.65; 95% CI: 0.46-0.90; p = 0.011). No statistically significant differences were seen for the other outcomes. CONCLUSION: Anaesthetic technique might influence time to discharge and bowel function in an ERAS setting. FUNDING: none TRIAL REGISTRATION: The study was approved by the Danish Data Protection Agency (record number 2008-58-0020). Under Danish law, consent from participants is not required in observational studies.

Association between diabetes and oncological outcomes in patients undergoing neoadjuvant chemo-radiotherapy for rectal cancer.

PURPOSE: The aim of the study was to investigate, in a nationwide study, if diabetes and especially metformin exposure during neoadjuvant chemo-radiotherapy improves the oncological outcomes in patients with rectal cancer. METHODS AND MATERIALS: Patients undergoing neoadjuvant chemo-radiotherapy and curative intended resection for rectal cancer in Denmark between January 1, 2003 and July 1, 2015 were identified. Diabetes was defined as medically treated diabetes. Only patients who were either active users of antidiabetic medication at the beginning of the radiotherapy or never-users were included. Active users were matched with never-users 1:2 by propensity score. Subgroup analyses concerning metformin treatment were performed. The primary outcome of the study was disease-free survival and the secondary outcomes were recurrence free survival and all-cause mortality. RESULTS: A total of 9799 patients were undergoing rectal cancer surgery with curative intend in the period. Of those, 2379 received neoadjuvant treatment up to one year preceding surgery. In total 459 patients were included in the study 154 patients with diabetes and 305 not diagnosed with diabetes. In the diabetes group, 53 were in active treatment with metformin. No statistical difference between the diabetes group and the non-diabetes group was shown with respect to disease free survival (HR 0.96, 95%CI 0.73-1.26, p = 0.77), recurrence-free survival (HR = 1.11, 95% CI 0.78-1.58, p = 0.56) or all-cause mortality (HR = 0.94, 95% CI 0.69-1.28, p = 0.69). Metformin treatment did not influence any of the outcomes. CONCLUSION: Our study does not support that diabetes or metformin use are associated with response to neoadjuvant chemo-radiotherapy in terms of disease-free survival, recurrence-free survival or all-cause mortality.

Association of Statin Use and Oncological Outcomes After Neoadjuvant Radiotherapy in Patients With Rectal Cancer.

AIM: The aim of the study was to examine if statin exposure during neoadjuvant chemoradiotherapy improves oncological outcomes in patients with rectal cancer. PATIENTS AND METHODS: The study cohort consisted of patients who were undergoing neoadjuvant chemoradiotherapy and resection for rectal cancer. The statin users were matched 1:1 with non-users using propensity score-based matching. The primary outcome of the study was disease-free survival; secondary outcomes were recurrence-free survival and all-cause mortality. RESULTS: A total of 704 patients were included in the study. Disease-free survival was not different between the two groups [hazard ratio (HR)=0.98, 95% confidence intervaI (CI)=0.77-1.25, p=0.88]. Both recurrence-free survival (HR=1.02, 95% CI=0.74-1.39, p=0.92) and all-cause mortality (HR=0.92, 95% CI=0.68-1.23, p=0.56) were similar for the two groups. CONCLUSION: The study does not support that statin use is associated with response to neoadjuvant chemoradiotherapy in terms of disease-free survival, recurrence-free survival or all-cause mortality.

Validation of a register-based algorithm for recurrence in rectal cancer.

INTRODUCTION: Colorectal cancer is the third most common type of cancer worldwide. Recurrence is an important end-point in colorectal cancer research. This study aimed to validate a previously developed algorithm to determine recurrence after surgery for rectal cancer. METHODS: Information about a cohort of 500 patients with rectal cancer was retrieved from the Danish Civil Registration System, the Danish National Patient Register and the Danish National Pathology Register. Patients with an ICD-10 code for metastatic disease, chemotherapy or SNOMED code suggesting metastasis were identified as having recurrence. In a previous study, medical records of the same cohort had been reviewed to identify recurrence. Recurrence identified by the algorithm was compared with the previously retrieved information from the medical records using Kappa statistics. The sensitivity and specificity of the algorithm were determined. RESULTS: Of the 500 patients, 393 were included in the validation analysis. Kappa statistics showed good concordance with a Kappa value (95% confidence interval) of 0.80 (0.72-0.88). The sensitivity and specificity of the algorithm were 88% (77-95%) and 96% (93-98%), respectively. CONCLUSIONS: The study showed good concordance between the algorithm and medical record information. The algorithm makes it possible to perform large register-based studies of recurrence and disease-free survival in colorectal cancer patients without the need for evaluation of medical records. FUNDING: none. TRIAL REGISTRATION: not relevant.

Association between robot-assisted surgery and resection quality in patients with colorectal cancer.

BACKGROUND: Resection quality after robot-assisted surgery for colorectal cancer have not previously been investigated in a nationwide study. The aim of the study was to examine the resection quality in robot-assisted versus laparoscopic surgery for colorectal cancer. Furthermore, 30-day mortality, postoperative complications, and conversion to open surgery were investigated. METHODS: Patients undergoing either laparoscopic or robot-assisted surgery for colorectal cancer between 1 January 2010 and 31 December 2015 were included. The primary outcome was whether R0 resection was achieved. Secondary outcomes were 30-day mortality, postoperative complications, and conversions to laparotomy. RESULTS: A total of 8615 and 3934 patients had a diagnosis of colon cancer and rectal cancer respectively. Of the patients with colon cancer, 511 patients underwent robot-assisted surgery and of the patients with rectal cancer, 706 patients underwent robot-assisted surgery. In the multivariate analysis, patients with colon cancer had an odds ratio (OR) = 0.63 (95%CI 0.45-0.88) for receiving R0 resection in the robot-assisted group compared to laparoscopy. For patients with rectal cancer, the OR was 1.20 (95%CI 0.89-1.61). No difference in 30-day mortality or postoperative complications were observed. The OR of conversion to laparotomy was lower in the robot-assisted group compared to the laparoscopic group in both patients with colon - and rectal cancer. CONCLUSIONS: The study showed significant lower odds of receiving R0 resection in patients with colon cancer undergoing robot-assisted surgery. In patients with rectal cancer the robot-assisted surgery non-significantly increased the odds of receiving R0 resection.