Rectal cancer : the influence of surgical technique on morbidity, mortality and survival

Surgery is still the most common treatment for rectal cancer, being the most effective and cost-efficient modality. However, it is not without risk, nor without controversies. This dissertation is an evaluation of the pros and cons of high versus low ligation, whether anastomotic leakage is still prevalent after surgery and associated with increased mortality, and if the risk of leakage could be predicted by early postoperative pain. Study I relied upon case records and registry data to evaluate the causal effect of high ligation on the risk of anastomotic leakage after anterior resection in 722 patients with increased cardiovascular risk. When controlling for confounders, no association was found overall. However, an increased risk for leakage after high ligation was noted for the few patients who suffered from both manifest cardiovascular disease and ASA III–IV (OR 3.66, 95% CI 1.04–12.85) and when performed in a low volume hospital (OR 3.89, 95% 1.58– 9.59). Study II estimated the risk of anastomotic leakage and death after anterior resection today. Among the 6,948 patients, 10.0% suffered from leakage, in whom mortality was 3.9% versus 1.5% for patients without a leak. However, this increased mortality was driven entirely by patients in need of reintervention, who exhibited a 7.5% 90-day mortality, resulting in a significantly increased risk (OR 5.57, 95% CI 3.29–9.44), when controlling for confounders, while conservatively treated leakage was not associated with mortality. Age acted as an effect modifier, as postoperative mortality after leakage was increased in the elderly. Study III returned to high versus low ligation as exposure, to evaluate the long-term oncological benefits of either ligation level, with cancer-specific survival as primary outcome. The final cohort of 8,287 patients who underwent abdominal surgery for rectal cancer, with curative intent, was followed for a minimum of 3.5 years. After propensity score matching, no significant differences were found between high and low ligation for any survival or recurrence analysis, nor in the unmatched cohort, when controlling for confounders. A statistically significant difference was found for lymph node harvest, which was slightly greater in high ligation (17.7 vs 16.7 lymph nodes). Finally, study IV estimated the independent predictive ability of postoperative pain, measured on the numerical rating scale (NRS), on the risk for anastomotic leakage after colorectal cancer surgery. It seems as if increased early pain is an independent predictor for leakage (OR 1.73, 95% CI 1.22– 2.46 for NRS 4–10), with increasing risk of leakage with increasing pain (OR 2.42 for NRS 8–10). In addition, increased pain was more strongly associated with more severe leakage. In summary, the level of ligation seems to be of importance only in a select group of high-risk patients, but offers no obvious oncological advantages. The high incidence and serious sequelae of anastomotic leakage makes it one of the most important clinical challenges in colorectal surgery, with especially detrimental effects in the elderly. A better understanding of the causal pathways behind leakage, and the overall harm and benefit of ligation level and diverting stomas, might allow a better selection of treatment for future patients.Serietillhörighet och delnummer saknas i publikationen.</p

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

Population‐based cohort study of the impact on postoperative mortality of anastomotic leakage after anterior resection for rectal cancer

Background: Anastomotic leakage following anterior resection for rectal cancer may result in death. The aim of this study was to yield an updated, population‐based estimate of postoperative mortality and evaluate possible interacting factors. Methods: This was a retrospective national cohort study of patients who underwent anterior resection between 2007 and 2016. Data were retrieved from a prospectively developed database. Anastomotic leakage constituted exposure, whereas outcome was defined as death within 90 days of surgery. Logistic regression analyses, using directed acyclic graphs to evaluate possible confounders, were performed, including interaction analyses. Results: Of 6948 patients, 693 (10·0 per cent) experienced anastomotic leakage and 294 (4·2 per cent) underwent reintervention due to leakage. The mortality rate was 1·5 per cent in patients without leakage and 3·9 per cent in those with leakage. In multivariable analysis, leakage was associated with increased mortality only when a reintervention was performed (odds ratio (OR) 5·57, 95 per cent c.i. 3·29 to 9·44). Leaks not necessitating reintervention did not result in increased mortality (OR 0·70, 0·25 to 1·96). There was evidence of interaction between leakage and age on a multiplicative scale (P = 0·007), leading to a substantial mortality increase in elderly patients with leakage. Conclusion: Anastomotic leakage, in particular severe leakage, led to a significant increase in 90‐day mortality, with a more pronounced risk of death in the elderly

Robotic low anterior resection with complete splenic flexure mobilization and defunctioning left-sided loop colostomy : a case series

A defunctioning stoma is used to alleviate the consequences of anastomotic leakage after low anterior resection for rectal cancer. A loop ileostomy is often preferred but may lead to dehydration and kidney injury. Here, we present a case series for an alternative: the left-sided loop colostomy. A convenience sample of four patients underwent robotic low anterior resection for rectal cancer. A complete splenic flexure mobilization and a total mesorectal excision were performed. To defunction the anastomosis, the redundant left colon was brought up to a stoma site in the left iliac fossa and matured as a loop colostomy. Two patients experienced minor stoma leaks and one also had a small prolapse, while all patients had their colostomies reversed on average 7 months after surgery without complications. There were no dehydration episodes and creatinine levels remained within baseline levels at end of follow-up (on average 18 months)