Oncological Impact of High Vascular Tie After Surgery for Rectal Cancer: A Nationwide Cohort Study.

OBJECTIVE: The purpose of this study was to investigate the impact of tie level on oncological outcomes in rectal cancer surgery. SUMMARY BACKGROUND DATA: Theoretically, a high tie of the inferior mesenteric artery could facilitate removal of apical node metastases and improve tumor staging accuracy. However, no appropriately sized randomized controlled trial exists and results from observational studies are not consistent. METHODS: All stage I-III rectal cancer patients who underwent abdominal surgery with curative intention in 2007 to 2014 were identified and followed, using the Swedish Colorectal Cancer Registry. Primary outcome was cancer-specific survival, whereas overall and relative survival, locoregional and distant recurrence, and lymph node harvest were secondary outcomes, with high tie as exposure. We used propensity score matching to emulate a randomized controlled trial, and then performed Cox regression analyses to estimate hazard ratios (HRs) with confidence intervals (CIs). RESULTS: Some 8287 patients remained for analysis, of which 37% had high tie surgery. After propensity score matching, the 5-year cancer-specific survival rate was overall 86% and we found no association between the level of tie and cancer-specific (HR 0.92, 95% CI 0.79-1.07) or overall (HR 0.98, 95% CI 0.89-1.08) survival, nor to locoregional (HR 0.85, 95% CI 0.59-1.23) or distant (HR 1.01, 95% CI 0.88-1.15) recurrence, nor to relative survival (HR 1.05, 95% CI 0.85-1.28). Stratification and sensitivity analyses were similarly insignificant, after adjustment for confounding. Total lymph node harvest was, however, increased after high tie surgery (P < 0.01), but no differences were seen regarding positive nodes (P = 0.72). CONCLUSION: In this nationwide cohort study, the level of tie did not influence any patient-oriented oncological outcome, neither overall nor in node-positive patients. This would allow the patient's anatomical configuration and the surgeon's preferences to determine the level of tie.

Early postoperative pain as a marker of anastomotic leakage in colorectal cancer surgery.

PURPOSE: Even though anastomotic leakage after colorectal surgery is a major clinical problem in need of a timely diagnosis, early indicators of leakage have been insufficiently studied. We therefore conducted a population-based observational study to determine whether the patient's early postoperative pain is an independent marker of anastomotic leakage. METHODS: By combining the Swedish Colorectal Cancer Registry and the Swedish Perioperative Registry, we retrieved prospectively collected data on 3084 patients who underwent anastomotic colorectal surgery for cancer in 2014-2017. Postoperative pain, measured with the numerical rating scale (NRS), was considered exposure, while anastomotic leakage and reoperation due to leakage were outcomes. We performed logistic regression to evaluate associations, estimating odds ratios (ORs) and 95% confidence intervals (CIs), while multiple imputation was used to handle missing data. RESULTS: In total, 189 patients suffered from anastomotic leakage, of whom 121 patients also needed a reoperation due to leakage. Moderate or severe postoperative pain (NRS 4-10) was associated with an increased risk of anastomotic leakage (OR 1.69, 95% CI 1.21-2.38), as well as reoperation (OR 2.17, 95% CI 1.41-3.32). Severe pain (NRS 8-10) was more strongly related to leakage (OR 2.38, 95% CI 1.44-3.93). These associations were confirmed in multivariable analyses and when reoperation due to leakage was used as an outcome. CONCLUSION: In this population-based retrospective study on prospectively collected data, increased pain in the post-anaesthesia care unit is an independent marker of anastomotic leakage, possibly indicating a need for further diagnostic measures.

Current use of diverting stoma in anterior resection for cancer: population-based cohort study of total and partial mesorectal excision.

PURPOSE: A diverting stoma is commonly used to reduce the risk of anastomotic leakage when performing total mesorectal excision (TME) in anterior resection for rectal cancer. The purpose of this study was to evaluate the impact of fecal diversion in relation to partial mesorectal excision (PME). METHODS: A retrospective analysis was undertaken on a national cohort, originally created to study the impact of central arterial ligation on patients with increased cardiovascular risk. Some 741 patients operated with anterior resection for rectal cancer during the years 2007 through 2010 were followed up for 53 months. Multivariate logistic regression was used to evaluate the impact of diverting stoma on the risk of anastomotic leakage and permanent stoma, expressed as odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: The risk of anastomotic leakage was increased in TME surgery when not using a diverting stoma (OR 5.1; 95% CI 2.2-11.6), while the corresponding risk increase in PME patients was modest (OR 1.8; 95% CI 0.8-4.0). At study completion or death, 26 and 13% of TME and PME patients, respectively, had a permanent stoma. A diverting stoma was a statistically significant risk factor for a permanent stoma in PME patients (OR 4.7; 95% CI 2.5-9.0), while less important in TME patients (OR 1.8; 95% CI 0.6-5.5). CONCLUSION: The benefit of a diverting stoma concerning anastomotic leakage in this patient group seems doubtful. Moreover, the diverting stoma itself may contribute to the high rate of permanent stomas.

Arterial ligation in anterior resection for rectal cancer: A validation study of the Swedish Colorectal Cancer Registry.

BACKGROUND: The level of arterial ligation has been a variable of the Swedish Colorectal Cancer Registry since 2007. The aim of this study is to evaluate the accuracy of this registry variable in relation to anterior resection for rectal cancer. METHODS: The operative charts of all cardiovascularly compromised patients who underwent anterior resection during the period 2007-2010 in Sweden were retrieved and compared to the registry. We selected the study population to reflect the common assumption that these patients would be more sensitive to a compromised visceral blood flow. Levels of vascular ligation were defined, both oncologically and functionally, and their sensitivity, specificity, positive and negative predictive values, level of agreement and Cohen's kappa were calculated. RESULTS: Some 744 (94.5%) patients were eligible for analysis. Functional high tie level showed a sensitivity of 80.2% and a specificity of 90.1%. Positive and negative predictive values were 87.7 and 83.8%, respectively. Level of agreement was 85.5% and Cohen's kappa 0.70. The corresponding calculations for oncologic tie level yielded similar results. CONCLUSION: The suboptimal validity of the Swedish Colorectal Cancer Registry regarding the level of vascular ligation might be problematic. For analyses with rare positive outcomes, such bowel ischaemia, or with minor expected differences in outcomes, it would be beneficial to collect data directly from the operative charts of the medical records in order to increase the chance of identifying clinically relevant differences.