National differences in implementation of minimally invasive surgery for colorectal cancer and the influence on short-term outcomes

Background

The timing and degree of implementation of minimally invasive surgery (MIS) for colorectal cancer vary among countries. Insights in national differences regarding implementation of new surgical techniques and the effect on postoperative outcomes are important for quality assurance, can show potential areas for country-specific improvement, and might be illustrative and supportive for similar implementation programs in other countries. Therefore, this study aimed to evaluate differences in patient selection, applied techniques, and results of minimal invasive surgery for colorectal cancer between the Netherlands and Sweden.

Methods

Patients who underwent elective minimally invasive surgery for T1-3 colon or rectal cancer (2012–2018) registered in the Dutch ColoRectal Audit or Swedish ColoRectal Cancer Registry were included. Time trends in the application of MIS were determined. Outcomes were compared for time periods with a similar level of MIS implementation (Netherlands 2012–2013 versus Sweden 2017–2018). Multilevel analyses were performed to identify factors associated with adverse short-term outcomes.

Results

A total of 46,095 Dutch and 8,819 Swedish patients undergoing MIS for colorectal cancer were included. In Sweden, MIS implementation was approximately 5 years later than in the Netherlands, with more robotic surgery and lower volumes per hospital. Although conversion rates were higher in Sweden, oncological and surgical outcomes were comparable. MIS in the Netherlands for the years 2012–2013 resulted in a higher reoperation rate for colon cancer and a higher readmission rate but lower non-surgical complication rates for rectal cancer if compared with MIS in Sweden during 2017–2018.

Conclusion

This study showed that the implementation of MIS for colorectal cancer occurred later in Sweden than the Netherlands, with comparable outcomes despite lower volumes. Our study demonstrates that new surgical techniques can be implemented at a national level in a controlled and safe way, with thorough quality assurance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-021-08974-1.

Permanent stoma rates after anterior resection for rectal cancer: risk prediction scoring using preoperative variables

BACKGROUND

A permanent stoma after anterior resection for rectal cancer is common. Preoperative counselling could be improved by providing individualized accurate prediction modelling.

METHODS

Patients who underwent anterior resection between 2007 and 2015 were identified from the Swedish Colorectal Cancer Registry. National Patient Registry data were added to determine presence of a stoma 2 years after surgery. A training set based on the years 2007-2013 was employed in an ensemble of prediction models. Judged by the area under the receiving operating characteristic curve (AUROC), data from the years 2014-2015 were used to evaluate the predictive ability of all models. The best performing model was subsequently implemented in typical clinical scenarios and in an online calculator to predict the permanent stoma risk.

RESULTS

Patients in the training set (n = 3512) and the test set (n = 1136) had similar permanent stoma rates (13.6 and 15.2 per cent). The logistic regression model with a forward/backward procedure was the most parsimonious among several similarly performing models (AUROC 0.67, 95 per cent c.i. 0.63 to 0.72). Key predictors included co-morbidity, local tumour category, presence of metastasis, neoadjuvant therapy, defunctioning stoma use, tumour height, and hospital volume; the interaction between age and metastasis was also predictive.

CONCLUSION

Using routinely available preoperative data, the stoma outcome at 2 years after anterior resection for rectal cancer can be predicted fairly accurately.

Cardiac risk stratification in emergency resection for colonic tumours

Background

Despite advances in perioperative care, the postoperative mortality rate after emergency oncological colonic resection remains high. Risk stratification may allow targeted perioperative optimization and cardiac risk stratification. This study aimed to test the hypothesis that the Revised Cardiac Risk Index (RCRI), a user-friendly tool, could identify patients who would benefit most from perioperative cardiac risk mitigation.

Methods

Patients who underwent emergency resection for colonic cancer from 2007 to 2017 and registered in the Swedish Colorectal Cancer Registry (SCRCR) were analysed retrospectively. These patients were cross-referenced by social security number to the Swedish National Board of Health and Welfare data set, a government registry of mortality, and co-morbidity data. RCRI scores were calculated for each patient and correlated with 90-day postoperative mortality risk, using Poisson regression with robust error of variance.

Results

Some 5703 patients met the study inclusion criteria. A linear increase in crude 90-day postoperative mortality was detected with increasing RCRI score (37.3 versus 11.3 per cent for RCRI 4 or more versus RCRI 1; P < 0.001). The adjusted 90-day all-cause mortality risk was also significantly increased (RCRI 4 or more versus RCRI 1: adjusted incidence rate ratio 2.07, 95 per cent c.i. 1.49 to 2.89; P < 0.001).

Conclusion

This study documented an association between increasing cardiac risk and 90-day postoperative mortality. Those undergoing emergency colorectal surgery for cancer with a raised RCRI score should be considered high-risk patients who would most likely benefit from enhanced postoperative monitoring and critical care expertise.

What is the risk of permanent stoma beyond 5 years after low anterior resection for rectal cancer? A 15-year follow-up of a randomized trial

AIM

Low anterior resection of the rectum for cancer (LAR) entails a risk of symptomatic anastomotic leakage as well as impaired anorectal function, both of which may eventually result in the need for a permanent stoma (PS). The aim was to investigate the incidence of and risk factors for PS beyond 5 years following LAR.

METHODS

Patients undergoing LAR and included in a multicentre trial with randomization to defunctioning stoma or not were followed for a median of 15 years. The reasons for a PS up to 5 years (PS ≤ 5 years) and beyond 5 years (PS > 5 years) were identified and compared. Risk factors for PS were analysed.

RESULTS

Of all patients, 25% (57/232) had a PS. PS ≤ 5 years occurred in 19% (44/232) at a median of 12.5 months and PS > 5 years in 6% (13/232) at a median of 118 months following LAR. The main reason for PS ≤ 5 years was impaired anorectal function in 55% (24/44) and the main reason for PS > 5 years was pelvic sepsis related to the colorectal anastomosis in 46% (6/13). The major risk factor for PS was symptomatic anastomotic leakage, which occurred in 56% (32/57) of patients with PS and 10% (17/175) of patients without PS (P < 0.001).

CONCLUSION

One-fourth of the patients who ended up with a PS had it fashioned beyond 5 years at a median of 10 years following LAR. Symptomatic anastomotic leakage was the major risk factor for PS, and impaired anorectal function was the main overall reason for a PS.

Low anterior resection syndrome in a Scandinavian population of patients with rectal cancer: a longitudinal follow-up within the QoLiRECT study

AIM

Low anterior resection syndrome (LARS) is common after low anterior resection. Our aim was to evaluate the prevalence and 'bother' (subjective, symptom-associated distress) of major LARS after 1 and 2 years, identify possible risk factors and relate the bowel function to a reference population.

METHOD

The QoLiRECT (Quality of Life in RECTal cancer) study is a Scandinavian prospective multicentre study including 1248 patients with rectal cancer, of whom 552 had an anterior resection. Patient questionnaires were distributed at diagnosis and after 1, 2 and 5 years. Data from the baseline and at 1- and 2-year follow-up were included in this study.

RESULTS

The LARS score was calculated for 309 patients at 1 year and 334 patients at 2 years. Prevalence was assessed by a generalized linear mixed effects model. Major LARS was found in 63% at 1 year and 56% at 2 years. Bother was evident in 55% at 1 year, decreasing to 46% at 2 years. Major LARS was most common among younger women (69%). Among younger patients, only marginal improvement was seen over time (63-59%), for older patients there was more improvement (62-52%). In the reference population, the highest prevalence of major LARS-like symptoms was noted in older women (12%). Preoperative radiotherapy, defunctioning stoma and tumour height were found to be associated with major LARS.

CONCLUSION

Major LARS is common and possibly persistent over time. Younger patients, especially women, are more affected, and perhaps these patients should be prioritized for early stoma closure to improve the chance of a more normal bowel function.

Self-reported sexual dysfunction in patients with rectal cancer

AIM

Patients with rectal cancer often experience sexual dysfunction after treatment. The aim of this study was to evaluate sexual function in a prospective cohort of patients regardless of treatment and tumour stage and explore what factors might affect sexual activity 1 year after diagnosis.

METHOD

The QoLiRECT study (Quality of Life in RECTal cancer) is a prospective study on the health-related quality of life in patients with rectal cancer in Denmark and Sweden. Questionnaires were completed at diagnosis and 1 year. Clinical data were retrieved from national quality registries.

RESULTS

Questionnaire data were available from 1085 patients at diagnosis and 920 patients at 1 year. Median age was 69 years (range 25-100). At diagnosis, 29% of the women and 41% of the men were sexually active, which was lower than an age-matched reference population. This was further reduced to 25% and 34% at 1 year. Risk factors for sexual inactivity were absence of sexual activity prior to the diagnosis and the presence of a stoma. Women experienced reduced lubrication and more dyspareunia at 1 year compared with the time of diagnosis. In men, erectile dysfunction increased from 46% to 55% at 1 year.

CONCLUSION

Sexual activity in patients with rectal cancer is lower at diagnosis compared with the population norm and is further reduced at 1 year. The presence of a stoma contributed to reduced sexual activity after operation. Sexual dysfunction was difficult to evaluate due to low sexual activity in the cohort. In men, erectile dysfunction is common.

Beta-blocker Therapy is Associated with Decreased 1-year Mortality After Emergency Laparotomy in Geriatric Patients

Background and Aims:

Emergency laparotomy is associated with a great risk of mortality in the elderly. The hyperadrenergic state induced by surgical trauma may play an important role in the pathophysiology of this increased risk. Studies have shown that beta-blocker exposure may be associated with decreased morbidity and mortality in the perioperative period. We aimed to study the effect of beta-blocker on mortality in geriatric patients undergoing emergency laparotomy.

Material and Methods:

This is a retrospective study of patients who underwent emergency laparotomy between 1 January 2015 and 31 December 2016 at a single institution. The outcomes of interest were the association between post-operative complications and in-hospital and 1-year mortality in patients on beta-blocker therapy (BB(+)) and those who were not (BB(−)). The Poisson regression analysis was used to evaluate the association.

Results:

A total of 192 patients were included of whom 62 (32.2%) had pre-operative beta-blocker therapy with continued exposure during their hospital stay. The in-hospital mortality was 17.7% in the BB(+) and 23.8% in the BB(−) cohorts ( p = 0.441). One-year mortality was significantly lower in the BB(+) group compared to the BB(−) group (30.6% versus 47.7%; p = 0.038). After adjusting for confounders, the incidence of deaths during 1 year post-operatively decreased by 35% in the BB(+) group (incidence rate ratio = 0.65, p = 0.004). No significant differences in the incidence of post-operative complications between the two groups could be measured.

Conclusion:

Beta-blocker therapy may be associated with reduced 1-year mortality following emergency laparotomy in geriatric patients.

A nationwide study on the incidence of mesenteric ischaemia after surgery for rectal cancer demonstrates an association with high arterial ligation

AIM

The incidence of mesenteric ischaemia after resection for rectal cancer has not been investigated in a population-based setting. The use of high ligation of the inferior mesenteric artery might cause such ischaemia, as the bowel left in situ depends on collateral blood supply after a high tie.

METHOD

The Swedish Colorectal Cancer Registry was used to identify all patients subjected to an abdominal resection for rectal cancer during the years 2007-2017 inclusive. Mesenteric ischaemia within the first 30 postoperative days was recorded, classified as either stoma necrosis or colonic necrosis. Multivariable logistic regression was used to estimate odds ratios (ORs) with 95% confidence intervals (CIs) for mesenteric ischaemia in relation to high tie, with adjustment for confounding.

RESULTS

Some 14 657 patients were included, of whom 59 (0.40%) had a reoperation for any type of mesenteric ischaemia, divided into 34 and 25 cases of stoma necrosis and colonic necrosis, respectively. Compared with patients who did not require reoperation for mesenteric ischaemia following rectal cancer surgery, the proportion having high tie was greater (54.2% vs 38.5%; P = 0.032). The adjusted OR for reoperation due to any mesenteric ischaemia with high tie was 2.26 (95% CI 1.34-3.79), while the corresponding estimates for stoma and colonic necrosis, respectively, were 1.60 (95% CI 0.81-3.17) and 3.69 (95% CI 1.57-8.66).

CONCLUSION

The incidence of reoperation for mesenteric ischaemia after abdominal resection for rectal cancer is low, but the use of a high tie might increase the risk of colonic necrosis demanding surgery.

Total Mesorectal Excision for Mid-Rectal Cancer Without Anastomosis: Low Hartmann’s Operation or Intersphincteric Abdomino-Perineal Excision?

Background and Aims:

In mid-rectal cancer, the low colorectal anastomosis is, although feasible, sometimes avoided. The aim was to compare low Hartmann’s procedure with intersphincteric abdomino-perineal excision of the rectum, in patients operated with total mesorectal excision for mid-rectal cancer in whom the low anastomosis was technically feasible but for patient-related reasons undesired.

Material and Methods:

A total of 64 consecutive patients with mid-rectal cancer who underwent low Hartmann’s procedure (n = 34) or intersphincteric abdomino-perineal excision (n = 30) at one colorectal unit were compared regarding patient demography, short-term oncology, surgical outcome at 3 and 24 months, and long-term overall survival.

Results:

There were no significant differences between intersphincteric abdomino-perineal excision and Hartmann’s procedure regarding age, gender distribution, body mass index, preoperative radiotherapy, tumor level, or cancer stages. Operation time was shorter in Hartmann’s procedure as compared with intersphincteric abdomino-perineal excision, median 174 and 256 min, (P < 0.001), and intraoperative blood loss was increased, 600 and 500 mL, respectively (P = 0.045). Number of lymph nodes and circumferential resection margin were comparable. In Hartmann’s procedure compared with intersphincteric abdomino-perineal excision, the need for reoperation was 24% and 3%, (P = 0.020), complications classified as Clavien–Dindo 3–4 occurred in 32% and 10%, (P = 0.031), pelvic abscess in 21% and 10%, (P = 0.313), and mortality within 90 days was 3% and 0%, respectively, (P = 0.938). In intersphincteric abdomino-perineal excision, the perineal wound was not healed at 3 months in 13%, and in Hartmann’s procedure 15% had chronic secretion from the anorectal remnant at 2 years postoperatively.

Conclusion:

The results from this study suggest that intersphincteric abdomino-perineal excision might be an alternative to Hartmann’s procedure in patients with mid-rectal cancer, in whom a low colorectal anastomosis is undesired.

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.

Effect of beta-blocker therapy on early mortality after emergency colonic cancer surgery

Background

Emergency colorectal cancer surgery is associated with significant mortality. Induced adrenergic hyperactivity is thought to be an important contributor. Downregulating the effects of circulating catecholamines may reduce the risk of adverse outcomes. This study assessed whether regular preoperative beta-blockade reduced mortality after emergency colonic cancer surgery.

Methods

This cohort study used the prospectively collected Swedish Colorectal Cancer Registry to recruit all adult patients requiring emergency colonic cancer surgery between 2011 and 2016. Patients were subdivided into those receiving regular beta-blocker therapy before surgery and those who were not (control). Demographics and clinical outcomes were compared. Risk factors for 30-day mortality were evaluated using Poisson regression analysis.

Results

A total of 3187 patients were included, of whom 685 (21·5 per cent) used regular beta-blocker therapy before surgery. The overall 30-day mortality rate was significantly reduced in the beta-blocker group compared with controls: 3·1 (95 per cent c.i. 1·9 to 4·7) versus 8·6 (7·6 to 9·8) per cent respectively (P &lt; 0·001). Beta-blocker therapy was the only modifiable protective factor identified in multivariable analysis of 30-day all-cause mortality (incidence rate ratio 0·31, 95 per cent c.i. 0·20 to 0·47; P &lt; 0·001) and was associated with a significant reduction in death of cardiovascular, respiratory, sepsis and multiple organ failure origin.

Conclusion

Preoperative beta-blocker therapy may be associated with a reduction in 30-day mortality following emergency colonic cancer surgery.

Effect of radiotherapy for rectal cancer on ovarian androgen production

Background

The impact of radiotherapy (RT) for rectal cancer on ovarian androgen production is unknown. The aim was to examine the effect of RT for rectal cancer on androgen levels in non-oophorectomized women and the association with female sexual desire.

Methods

This prospective cohort study included women who had surgery for rectal cancer with or without RT. Serum testosterone, free testosterone, androstenedione and dehydroepiandrosterone sulphate (DHEA-S) levels were assessed at baseline, after RT and 1 year after surgery. Sexual desire was assessed by means of the Female Sexual Function Index.

Results

Twenty-seven participants had surgery alone (RT– group) and 98 had preoperative RT and surgery (RT+ group). During the first year after surgery, median serum testosterone and free testosterone levels decreased from 0·6 (range 0·1–3·6) to 0·5 (0·1–2·3) nmol/l (P &lt; 0·001) and from 9·1 (1·6–45·8) to 7·9 (1·4–22·7) pmol/l (P &lt; 0·001) respectively in the RT+ group, but did not change in the RT– group. Longitudinal regression analysis confirmed a decrease in testosterone and free testosterone after RT. The adjusted change in androstenedione and DHEA-S was not significant in any group. The mean change in testosterone (odds ratio (OR) 2·74, 95 per cent c.i. 1·06 to 7·11; P = 0·038), free testosterone (OR 1·08, 1·02 to 1·15; P = 0·011), androstenedione (OR 1·52, 1·07 to 2·16; P = 0·019) and DHEA-S (OR 0·49, 0·27 to 0·89; P = 0·019) was related to change in sexual desire.

Conclusion

RT decreased levels of androgens predominantly derived from the ovaries, whereas androgens of mainly adrenal origin remained unchanged. Reduction in ovarian androgens may be associated with reduced sexual desire.

BAX 855, a PEGylated rFVIII product with prolonged half-life

A longer acting recombinant FVIII is expected to serve patients’ demand for a more convenient prophylactic therapy. We have developed BAX 855, a PEGylated form of Baxter’s rFVIII product ADVATE™ based on the ADVATE™ manufacturing process. The conjugation process for preparing BAX 855 uses a novel PEG reagent. The production process was adjusted to yield a rFVIII conjugate with a low PEGylation degree of about 2 moles PEG per FVIII molecule. This optimised modification degree resulted in an improved PK profile for rFVIII without compromising its specific activity. PEGylation sites were identified by employing various HPLC- and MS-based methods. These studies not only indicated that about 60% of the PEG chains are localised to the B-domain, which is cleaved off upon physiological activation during the coagulation process, but also demonstrated an excellent lot to lot consistency with regard to PEGylation site distribution. Detailed biochemical characterization further showed that PEGylated FVIII retained all the physiological functions of the FVIII molecule with the exception of binding to the LRP clearance receptor which was reduced for BAX 855 compared to ADVATE™. This might provide an explanation for the prolonged circulation time of BAX 855 as reduced receptor binding might slow-down clearance. Preclinical studies showed improved pharmacokinetic behaviour and clinically relevant prolonged efficacy compared to ADVATE™ without any signs of toxicity or elevated immunogenicity. The comprehensive preclinical data package formed the basis for approval of the phase 1 clinical study by European authorities which started in 2011.

High stoma prevalence and stoma reversal complications following anterior resection for rectal cancer: a population-based multicentre study

AIM

Fashioning a defunctioning stoma is common when performing an anterior resection for rectal cancer in order to avoid and mitigate the consequences of an anastomotic leakage. We investigated the permanent stoma prevalence, factors influencing stoma outcome and complication rates following stoma reversal surgery.

METHOD

Patients who had undergone an anterior resection for rectal cancer between 2007 and 2013 in the northern healthcare region were identified using the Swedish Colorectal Cancer Registry and were followed until the end of 2014 regarding stoma outcome. Data were retrieved by a review of medical records. Multiple logistic regression was used to evaluate predefined risk factors for stoma permanence. Risk factors for non-reversal of a defunctioning stoma were also analysed, using Cox proportional-hazards regression.

RESULTS

A total of 316 patients who underwent anterior resection were included, of whom 274 (87%) were defunctioned primarily. At the end of the follow-up period 24% had a permanent stoma, and 9% of patients who underwent reversal of a stoma experienced major complications requiring a return to theatre, need for intensive care or mortality. Anastomotic leakage and tumour Stage IV were significant risk factors for stoma permanence. In this series, partial mesorectal excision correlated with a stoma-free outcome. Non-reversal was considerably more prevalent among patients with leakage and Stage IV; Stage III patients at first had a decreased reversal rate, which increased after the initial year of surgery.

CONCLUSION

Stoma permanence is common after anterior resection, while anastomotic leakage and advanced tumour stage decrease the chances of a stoma-free outcome. Stoma reversal surgery entails a significant risk of major complications.

Level of vascular tie and its effect on functional outcome 2 years after anterior resection for rectal cancer

AIM

Previous research indicates that high tie of the inferior mesenteric artery during anterior resection for rectal cancer might be associated with an increased risk of postoperative functional disturbances. The goal of this population-based retrospective cohort study was to further investigate that association.

METHOD

Patients who underwent anterior resection for rectal cancer from April 2011 to September 2012 were identified through the Swedish Colorectal Cancer Registry. Bowel and urogenital function were assessed by a postal questionnaire 2 years after surgery. Information on the level of mesenteric tie and clinical variables was retrieved from the registry. The outcome was defined as any defaecatory, urinary or sexual dysfunction as reported by the patient. The association between high tie and the outcome was evaluated with multivariable logistic and linear regression with adjustment for confounders, such as sex, body mass index, comorbidity and preoperative radiation.

RESULTS

With a response rate of 86%, 805 patients were included in the study. Of these, 46% were operated with high tie. After adjustment for confounders, high tie did not affect the risk of faecal incontinence (OR 0.85; 95% CI 0.59-1.22), urinary incontinence (OR 0.94; 95% CI 0.63-1.41) or various aspects of sexual dysfunction (erectile dysfunction, anejaculation, dyspareunia and coital vaginal dryness). However, an association between high tie and defaecation at night was detected (OR 1.44; 95% CI 1.02-2.03).

CONCLUSION

This study does not support that the level of vascular tie influences the risk of major defaecatory, urinary or sexual disturbances 2 years after anterior resection for rectal cancer.

Nonsteroidal anti-inflammatory drugs and the risk of anastomotic leakage after anterior resection for rectal cancer

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been widely used in colorectal surgery due to their opioid-sparing effect. However, several studies have indicated an increased risk of anastomotic leakage following NSAID treatment, although conflicting results exist. The primary goal of this study was to further examine whether postoperative NSAIDs are independently associated with anastomotic leakage after anterior resection for rectal cancer.

METHODS

Patients who underwent anterior resection for rectal cancer during 2007-2013 in 15 different hospitals in three healthcare regions in Sweden were included in the study. Registry data and information from patient records were retrieved. The association between NSAID treatment (for at least two days in the first postoperative week) and symptomatic anastomotic leakage (within 90 days) was evaluated with multiple logistic regression, with adjustment for pertinent confounding factors.

RESULTS

Some 1495 patients were included in the study. Of these, 27% received postoperative NSAIDs for at least two days in the first postoperative week. Symptomatic anastomotic leakage occurred in 11% and 14% in the NSAID and non-NSAID group, respectively. With adjustment for confounders, the odds ratio for leakage among patients who received NSAIDs compared with those who did not was 0.88 (95% CI 0.65-1.20). No differences were seen between non-selective and COX-2-selective NSAIDs.

CONCLUSION

Postoperative NSAID treatment does not seem to increase the risk of symptomatic anastomotic leakage after anterior resection for rectal cancer. NSAID use appears to be safe, but a well-powered randomized clinical trial is warranted.

Surgical and not analgesic technique affects postoperative inflammation following colorectal cancer surgery: a prospective, randomized study

AIM

Epidural analgesia reduces the surgical stress response. However, its effect on pro- and anti-inflammatory cytokines in the genesis of inflammation following major abdominal surgery remains unclear. Our main objective was to elucidate whether perioperative epidural analgesia prevents the inflammatory response following colorectal cancer surgery.

METHODS

Ninety-six patients scheduled for open or laparoscopic surgery were randomized to epidural analgesia (group E) or patient-controlled intravenous analgesia (group P). Surgery and anaesthesia were standardized in both groups. Plasma cortisol, insulin and serum cytokines [interleukin 1β (IL-1β), IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumour necrosis factor α, interferon γ, granulocyte-macrophage colony-stimulating factor, prostaglandin E₂ and vascular endothelial growth factor] were measured preoperatively (T0), 1-6 h postoperatively (T1) and 3-5 days postoperatively (T2). Mixed model analysis was used, after logarithmic transformation when appropriate, for analyses of cytokines and stress markers.

RESULTS

>There were no significant differences in any serum cytokine concentration between groups P and E at any time point except for IL-10 which was 87% higher in group P [median and range 4.1 (2.3-9.2) pg/ml] compared to group E [2.6 (1.3-4.7) pg/ml] (P = 0.002) at T1. There was no difference in plasma cortisol and insulin between the groups at any time point after surgery. A significant difference in median serum cytokine concentration was found between open and laparoscopic surgery with higher levels of IL-6, IL-8 and IL-10 at T1 in patients undergoing open surgery compared to laparoscopic surgery. No difference in serum cytokine concentration was detected between the groups or between the surgical technique at T2.

CONCLUSIONS

Open surgery, compared to laparoscopic surgery, has greater impact on these inflammatory mediators than epidural analgesia vs intravenous analgesia.

Laparoscopic and open right-sided colonic resection in daily routine practice. A prospective multicentre study within an Enhanced Recovery After Surgery (ERAS) protocol

AIM

The study compared the outcome of laparoscopic and open surgery in daily practice when performed in a strict Enhanced Recovery After Surgery (ERAS) environment.

METHOD

Two-hundred and ninety-two consecutive patients who received elective surgery, in three Swedish ERAS centres, for cancer or adenoma in the right colon in the period 1 January 2011 to 31 December 2012, were prospectively registered in a Web-based ERAS database. Peri-operative data were collected from the database and patient charts. The primary end-points included postoperative recovery and morbidity. The secondary objective was to identify preoperative variables that influenced the selection of patients for laparoscopic or open surgery.

RESULTS

One-hundred and twenty-three (42%) patients were selected for laparoscopic surgery. The overall preoperative ERAS-compliance rate was 87% and no significant difference was seen between the surgical techniques. In multivariate analysis, patients treated with laparoscopy had significantly earlier pain control (2.4 ± 3.2 days vs 4.2 ± 5.9 days; P = 0.016) and a shorter length of hospital stay (LOS) (4 days vs 6 days; P = 0.002) compared with open surgery. There was no significant difference in the complication rate [18.7% vs 21.3%; OR = 1.0 (95% CI: 0.5-2.0)], the number of lymph nodes removed or the rate of R0 resection between laparoscopic and open surgery. Tumours selected for laparoscopy were generally smaller, had a lower T-stage and were predominantly situated in the caecum and the ascending colon compared with those of patients selected for open surgery.

CONCLUSION

The use of laparoscopy in routine right-sided colectomy in an ERAS environment, with data on outcome corrected for selection bias, may result in faster recovery compared with open surgery.

High arterial ligation and risk of anastomotic leakage in anterior resection for rectal cancer in patients with increased cardiovascular risk

AIM

Controversy still exists as to whether division of the inferior mesenteric artery close to the aorta influences the risk of anastomotic leakage after anterior resection for rectal cancer. This population-based study was carried out to evaluate the independent association between high arterial ligation and anastomotic leakage in patients with increased cardiovascular risk.

METHOD

All 2673 cases of registered anterior resection for rectal cancer from 2007 to 2010 were identified from the Swedish Colorectal Cancer Registry and cross-referenced with the Prescribed Drugs Registry, rendering a cohort of all patients with increased cardiovascular risk. Operative charts and registered data were reviewed for 722 patients. The association between high tie and anastomotic leakage, as quantified by ORs and 95% CIs, was evaluated in a logistic regression model, with adjustment for confounding, including assessment of interaction.

RESULTS

Symptomatic anastomotic leakage occurred in 12.3% (41/334) of patients in the high tie group and in 10.6% (41/388) in the low tie group. The use of high tie was not independently associated with a higher risk of anastomotic leakage (OR = 1.05; 95% CI: 0.61-1.84). In a post-hoc analysis, patients with a history of manifest cardiovascular disease and American Society of Anesthesiologists (ASA) score III-IV seemed to be at greater risk (OR = 3.66; 95% CI: 1.04-12.85).

CONCLUSION

In the present population-based, observational setting, high tie was not independently associated with an increased risk of symptomatic anastomotic leakage after anterior resection for rectal cancer. However, this conclusion may not hold for patients with severe cardiovascular disease.

Anterior Resection for Rectal Cancer and Visceral Blood Flow: An Explorative Study

BACKGROUND AND AIMS

Impaired blood perfusion may be implicated in anastomotic leakage after anterior resection for rectal cancer. We investigated whether high ligation of the inferior mesenteric artery or total mesorectal excision compromises visceral blood flow in the colonic limb and the rectal stump, respectively.

MATERIAL AND METHODS

A prospective cohort study was conducted in a university hospital setting. We used Laser Doppler flowmetry to evaluate the impact of level of tie on colonic limb perfusion and the extent of the mesorectal excision on the rectal blood flow. In the rectum, different quadrants were also assessed. The Mann-Whitney U test was used to compare mean blood flow ratios between groups.

RESULTS

Some 23 patients were recruited in a convenience sample during a period in 2012-2013. The mean blood flow ratio was not decreased after high tie compared to low tie surgery (1.71 vs 1.19; p = 0.28). Total mesorectal excision reduced the mean blood flow ratio in the rectum, as compared with partial mesorectal excision (0.76 vs 1.28; p = 0.14). This was especially pronounced in the posterior aspect of the rectum (0.66 vs 1.68; p = 0.02).

CONCLUSION

High tie ligation did not seem to decrease colonic limb perfusion, while total mesorectal excision may decrease rectal blood flow. The posterior quadrant of the rectum might be particularly vulnerable to the dissection involved in total mesorectal excision.

Early postoperative mortality after surgery for rectal cancer in Sweden, 2000-2011

AIM

Postoperative mortality has traditionally been defined as death within 30 days of surgery. Such mortality after rectal cancer resection has declined significantly during the last decades. However, it is possible that this decline can be explained merely by a shift towards an increase in 90-day mortality.

METHOD

A nationwide cohort study was based on data from the Swedish Colorectal Cancer Registry and the Swedish Patient Registry concerning patients who had undergone surgical resection for rectal cancer in 2000-2011. Unconditional logistic regression was used to calculate ORs with 95% CIs regarding mortality in different calendar periods (2000-2003, 2004-2007 and 2008-2011) in two different postoperative time periods (0-30 days and 31-90 days).

RESULTS

Some 15,437 patients were included in this surgical cohort. Mortality within 30 days of surgery decreased from 2.1% in 2000-2003 to 1.6% in 2008-2011, whilst the corresponding mortality within the 31- to 90-day time window decreased from 2.1% to 1.4%. The adjusted risk of 30-day mortality in 2008-2011 was statistically significantly decreased compared with that in 2000-2003 (OR = 0.67; 95% CI: 0.48-0.93) and mortality in the 31- to 90-day time window was also reduced for 2008-2011 compared with 2000-2003 (OR = 0.71; 95% CI: 0.51-0.99).

CONCLUSION

This population-based, nationwide Swedish study indicates that postoperative mortality, as measured within 30 days and 31-90 days after surgery, has decreased with time. However, no relevant shift from earlier to later postoperative mortality was discerned.

Degree of specialisation of the surgeon influences lymph node yield after right-sided hemicolectomy

AIM

To investigate the degree to which specialisation or case-load of the surgeon is associated with the number of lymph nodes isolated from pathology specimens after right-sided hemicolectomy.

METHOD

Data from 6 hospitals with well-defined catchment areas included in the Uppsala/Örebro Regional Oncology Centre Colon Cancer Register 1997-2006 were used to assess 821 patients undergoing right-sided hemicolectomy for stages I-III colon cancer. Factors influencing the lymph node yield were evaluated.

RESULTS

A surgeon with colorectal accreditation and a university pathology department were both associated with a significantly higher proportion of patients having 12 or more lymph nodes isolated from surgical specimens after right-sided hemicolectomy in both unadjusted and multivariate analyses. Emergency surgery did not affect the lymph node yield.

CONCLUSION

The degree of specialisation of the surgeon influences the number of lymph nodes isolated from specimens obtained during routine right-sided colon cancer surgery.

When are defunctioning stomas in rectal cancer surgery really reversed? Results from a population-based single center experience

BACKGROUND AND AIMS

This study assessed the timing of reversal of defunctioning stoma following low anterior resection of the rectum for cancer and risk factors for a defunctioning stoma becoming permanent in patients who were not reversed.

MATERIAL AND METHODS

Patients who underwent low anterior resection with defunctioning stoma during a 12-year period were assessed with regard to timing of stoma reversal. Delayed reversal was defined as >4 months after low anterior resection. Patients with a defunctioning stoma that was never reversed were assessed regarding risk factors for permanent stoma.

RESULTS

A total of 134 patients were analyzed. Of 106 stoma reversals, 19% were reversed within 4 months of low anterior resection, while 81% were reversed later than 4 months. In 58% of these patients, the delay was to due to low medical priority given to this procedure. The other main reasons for delayed stoma reversal were nonsurgical complications (20%), symptomatic anastomotic leakage following low anterior resection (12%), and postoperative adjuvant chemotherapy (10%). Of all patients, 21% (28/134) ended up with a permanent stoma. Risk factors for a defunctioning stoma becoming permanent were stage IV cancer (P < 0.001) and symptomatic anastomotic leakage following low anterior resection (P < 0.001).

CONCLUSION

Four in five patients experienced a delayed stoma reversal, in a majority because of the low priority given to this surgical procedure.

Early and late symptomatic anastomotic leakage following low anterior resection of the rectum for cancer: are they different entities?

AIM

The aim of the study was to compare patients with symptomatic anastomotic leakage following low anterior resection of the rectum (LAR) for cancer diagnosed during the initial hospital stay with those in whom leakage was diagnosed after hospital discharge.

METHOD

Forty-five patients undergoing LAR (n = 234) entered into a randomized multicentre trial (NCT 00636948), who developed symptomatic anastomotic leakage, were identified. A comparison was made between patients diagnosed during the initial hospital stay on median postoperative day 8 (early leakage, EL; n = 27) and patients diagnosed after hospital discharge at median postoperative day 22 (late leakage, LL; n = 18). Patient characteristics, operative details, postoperative course and anatomical localization of the leakage were analysed.

RESULTS

Leakage from the circular stapler line of an end-to-end anastomosis was more common in EL, while leakage from the stapler line of the efferent limb of the J-pouch or side-to-end anastomosis tended to be more frequent in LL (P = 0.057). Intra-operative blood loss (P = 0.006) and operation time (P = 0.071) were increased in EL compared with LL. On postoperative day 5, EL performed worse than LL with regard to temperature (P = 0.021), oral intake (P = 0.006) and recovery of bowel activity (P = 0.054). Anastomotic leakage was diagnosed most often by a rectal contrast study in EL and by CT scan in LL. The median initial hospital stay was 28 days for EL and 10 days for LL (P < 0.001).

CONCLUSION

The present study has demonstrated that symptomatic anastomotic leakage can present before and after hospital discharge and raises the question of whether early and late leakage after LAR may be different entities.

BAX 855, a PEGylated rFVIII product with prolonged half-life. Development, functional and structural characterisation

A longer acting recombinant FVIII is expected to serve patients' demand for a more convenient prophylactic therapy. We have developed BAX 855, a PEGylated form of Baxter's rFVIII product ADVATE™ based on the ADVATE™ manufacturing process. The conjugation process for preparing BAX 855 uses a novel PEG reagent. The production process was adjusted to yield a rFVIII conjugate with a low PEGylation degree of about 2 moles PEG per FVIII molecule. This optimised modification degree resulted in an improved PK profile for rFVIII without compromising its specific activity. PEGylation sites were identified by employing various HPLC- and MS-based methods. These studies not only indicated that about 60% of the PEG chains are localised to the B-domain, which is cleaved off upon physiological activation during the coagulation process, but also demonstrated an excellent lot to lot consistency with regard to PEGylation site distribution. Detailed biochemical characterization further showed that PEGylated FVIII retained all the physiological functions of the FVIII molecule with the exception of binding to the LRP clearance receptor which was reduced for BAX 855 compared to ADVATE™. This might provide an explanation for the prolonged circulation time of BAX 855 as reduced receptor binding might slow-down clearance. Preclinical studies showed improved pharmacokinetic behaviour and clinically relevant prolonged efficacy compared to ADVATE™ without any signs of toxicity or elevated immunogenicity. The comprehensive preclinical data package formed the basis for approval of the phase 1 clinical study by European authorities which started in 2011.

Surgeon and hospital-related risk factors in colorectal cancer surgery

AIM

The aim of this study was to identify surgeon and hospital-related factors in a well-defined population-based cohort; the results of this study could possibly be used to improve outcome in colorectal cancer.

METHOD

Data from the colonic (1997-2006) and rectal (1995-2006) cancer registers of the Uppsala/Örebro Regional Oncology Centre were used to assess 1697 patients with rectal and 2692 with colonic cancer. Putative risk factors and their impact on long-term survival were evaluated using the Cox proportional hazard model.

RESULTS

The degree of specialization of the operating surgeon had no significant effect on long-term survival. When comparing the surgeons with the highest degree of specialization, noncolorectal surgeons demonstrated a slightly lower long-term survival for rectal cancer stage I and II (HR, 2.03; 95% CI, 1.05-3.92). Surgeons with a high case-load were not associated with better survival in any analysis model. Regional hospitals had a lower survival rate for rectal cancer stage III surgery (HR, 1.47; 95% CI, 1.08-2.00).

CONCLUSION

Degree of specialization, surgeon case-load and hospital category could not be identified as important factors when determining outcome in colorectal cancer surgery in this study.

High tie in anterior resection for rectal cancer confers no increased risk of anastomotic leakage

BACKGROUND

It is controversial whether division of the inferior mesenteric artery close to the aorta influences the risk of anastomotic leakage, especially in the elderly and unfit. This population-based study was carried out to evaluate the independent association between a high arterial ligation and anastomotic leakage in anterior resection for rectal cancer.

METHODS

All patients who had anterior resection for rectal cancer from 2007 to 2009 inclusive were identified in the Swedish Colorectal Cancer Registry. The association between high tie and anastomotic leakage was evaluated in a logistic regression model, with adjustment for confounders. Stratification was performed for co-morbidity as judged by the American Society of Anesthesiologists (ASA) classification.

RESULTS

Symptomatic anastomotic leakage occurred in 81 (9·9 per cent) of 818 patients with a high tie and 108 (9·8 per cent) of 1101 without. Overall, the use of a high tie was not associated with a higher risk of anastomotic leakage (odds ratio (OR) 1·00, 95 per cent confidence interval 0·72 to 1·39). There was no increased risk in patients classifed as ASA grade I or II (OR 0·97, 0·69 to 1·35), or in those graded ASA III or IV (OR 1·26, 0·58 to 2·75).

CONCLUSION

In the present population-based setting, use of a high tie was not associated with an increased rate of symptomatic anastomotic leakage.

Indices of stress in three-spined sticklebacks Gasterosteus aculeatus in relation to extreme weather events and exposure to wastewater effluent

Whole-body concentrations of cortisol and glucose were measured in three-spined sticklebacks Gasterosteus aculeatus from two rivers (Rivers Ray and Ock) in southern England during a 30 month period in order to assess effects on the stress axis of (1) remediation of a wastewater treatment works (WWTW) effluent (River Ray) and (2) episodic changes in flow rate arising from periods of high rainfall (Rivers Ray and Ock). The postcapture concentrations of cortisol and glucose in fish from both rivers did not exhibit a seasonal periodicity but did show significant between-sample, between-site and between-river variation, superimposed upon a consistent downward trend for each analyte during the monitoring period. Corticosteroid and glucose concentrations following capture were inversely linked with a progressive increase in condition of the fish during this period. Site-dependent trends possibly related to exposure to the WWTW effluent were detected for both analytes in fish from the River Ray. For fish in the River Ray, a significant proportion of variation in both corticosteroid and glucose concentrations, additional to the downward trend with time, was accounted for by temporal proximity of the sample to exceptional flow events arising from episodes of high rainfall and high turbidity. This relationship was not statistically significant for fish from the River Ock. These data suggest that the responsiveness of the stress axis in free-living G. aculeatus may be altered by exposure to WWTW effluent and by exposure to physical changes in the aquatic environment such as those arising from extreme weather events. The magnitude of these effects may be increased by exposure to both stressors concurrently.

Symptomatic anastomotic leakage diagnosed after hospital discharge following low anterior resection for rectal cancer

OBJECTIVE

The aim of this study was to investigate patients with symptomatic anastomotic leakage diagnosed after hospital discharge.

METHOD

Patients (n = 234) undergoing low anterior resection of the rectum for cancer who were included in a prospective multicentre trial (NCT 00636948) and who developed symptomatic anastomotic leakage diagnosed after hospital discharge (late leakage, LL; n = 18) were identified. Patient characteristics, operative details, recovery on postoperative day 5, length of hospital stay, and how the leakage was diagnosed were recorded. A comparison with those who did not develop symptomatic leakage (no leakage, NL; n = 189) was made. The minimum follow up was 24 months.

RESULTS

In the LL patients the median age was 69 years, 61% were female patients, and 6% had stage IV cancer disease. On postoperative day 5, the LL group had a postoperative course similar to the NL group regarding temperature, oral intake and bowel function. The proportion of patients on antibiotic treatment on postoperative day 5, regardless of indication, was 28% in the LL compared with 4% in the NL group (P < 0.001). The median initial hospital stay was 10 days for both groups. When readmission for any reason was added, the hospital stay rose to a median of 21.5 and 13 days in the LL and the NL groups respectively (P < 0.001).

CONCLUSION

Symptomatic anastomotic leakage diagnosed after hospital discharge following low anterior resection of the rectum for cancer is not uncommon and has an immediate clinical postoperative course which may appear uneventful.

Elevated intraperitoneal matrix metalloproteinases-8 and -9 in patients who develop anastomotic leakage after rectal cancer surgery: a pilot study

OBJECTIVE

Experimental studies suggest that matrix metalloproteinase (MMP) enzymes mediate the early tissue breakdown that leads to a decrease in intestinal anastomotic strength. Patients with upregulation of MMPs in intestinal biopsies have an increased rate of anastomotic leakage. We measured MMPs and their inhibitors [tissue inhibitors of metalloproteinases (TIMPs)] in postoperative intraperitoneal fluid after rectal cancer surgery, and hypothesized that they would be elevated in patients who later would develop anastomotic leakage.

METHOD

Twenty-nine patients with rectal carcinoma underwent low anterior resection of the rectum for cancer. Intraperitoneal fluid was collected via a pelvic drain at a median of 4 h postoperatively. MMP-1, -2, -3, -7, -8, -9 and -13 were determined using particle-based multiplex flow-cytometry. TIMP-1 and -2 were measured by enzyme-linked immunosorbent assays. MMP-9 was considered the main outcome variable. RESULTS; Ten patients developed anastomotic leakage. These patients had increased intraperitoneal MMP-9 [median difference (m.d.) 29%; P = 0.03] and MMP-8 (m.d. 58%; P = 0.02), compared with patients who did not develop leakage. There were no differences between the groups for other MMPs and TIMPs.

CONCLUSION

Matrix metalloproteinase-8 and -9 appear to have an important role in the development of anastomotic leakage and may be promising pharmacological targets to protect anastomotic integrity. We suggest further investigation of MMPs as markers for anastomotic leakage.

Anastomotic-vaginal fistula (AVF) after anterior resection of the rectum for cancer--occurrence and risk factors

OBJECTIVE

The aim of the study was to assess recto-vaginal fistula (RVF) after anterior resection of the rectum for cancer with regard to occurrence and risk factors.

METHOD

All female patients [median age 69.5 years, Union Internationale centre le Cancer (UICC) cancer stage IV in 10%] who developed a symptomatic RVF (n = 20) after anterior resection of the rectum for cancer from three separate cohorts of patients were identified and compared with those who developed conventional symptomatic leakage (n = 32), and those who did not leak (n = 338). Patient demography and perioperative data were compared between these three groups. Fourteen patient-related and surgery-related variables thought to be possible risk factors for RVF (anastomotic-vaginal fistula) were analysed.

RESULTS

Symptomatic anastomotic leakage occurred in 52 (13.3%) of 390 patients. Twenty (5.1%) had an anastomotic-vaginal fistula (AVF) and 32 (8.2%) conventional leakage (CL). Patients with AVF required unscheduled re-operation and defunctioning stoma as often as those with CL. AVF was diagnosed later and more often after discharge from hospital compared with CL. Patients with AVF had lower anastomoses and decreased BMI compared with those with CL. Risk factors for AVF in multivariate analysis were anastomosis < 5 cm above the anal verge (P = 0.001), preoperative radiotherapy (P = 0.004), and UICC cancer stage IV (P = 0.005). Previous hysterectomy was a risk factor neither for AVF nor for CL.

CONCLUSION

Anastomotic-vaginal fistula forms a significant part of all symptomatic leakages after low anterior resection for cancer in women. Although diagnosed later, the need for abdominal re-operation and defunctioning stoma was not different from patients with CL. Risk factors for AVF included low anastomosis, preoperative radiotherapy and UICC cancer stage IV.

COLOR II. A randomized clinical trial comparing laparoscopic and open surgery for rectal cancer

INTRODUCTION

Laparoscopic resection of rectal cancer has been proven efficacious but morbidity and oncological outcome need to be investigated in a randomized clinical trial.

TRIAL DESIGN

Non-inferiority randomized clinical trial.

METHODS

The COLOR II trial is an ongoing international randomized clinical trial. Currently 27 hospitals from Europe, South Korea and Canada are including patients. The primary endpoint is loco-regional recurrence rate three years post-operatively. Secondary endpoints cover quality of life, overall and disease free survival, post-operative morbidity and health economy analysis.

RESULTS

By July 2008, 27 hospitals from the Netherlands, Belgium, Germany, Sweden, Spain, Denmark, South Korea and Canada had included 739 patients. The intra-operative conversion rate in the laparoscopic group was 17%. Distribution of age, location of the tumor and radiotherapy were equal in both treatment groups. Most tumors are located in the mid-rectum (41%).

CONCLUSION

Laparoscopic surgery in the treatment of rectal cancer is feasible. The results and safety of laparoscopic surgery in the treatment of rectal cancer remain unknown, but are subject of interim analysis within the COLOR II trial. Completion of inclusion is expected by the end of 2009.

TRIAL REGISTRATION

Clinicaltrials.gov, identifier: NCT00297791 (www.clinicaltrials.gov).

Increase of serum C-reactive protein is an early indicator of subsequent symptomatic anastomotic leakage after anterior resection

OBJECTIVE

This prospective study investigated the factors which might indicate anastomotic leakage after low anterior resection.

METHOD

Thirty-three patients who underwent anterior resection for rectal carcinoma (n = 32) and severe dysplasia (n = 1), were monitored daily by serum C-reactive protein (CRP) and white blood cell count (WBC) estimations until discharge from hospital. Computed tomography (CT) scans were performed on postoperative days 2 and 7 and the amount of presacral fluid collection was assessed. All patients had a pelvic drain and the volume of drainage was measured daily.

RESULTS

The level of the anastomosis was at a median 5 cm (3-12 cm) above the anal verge. There was no 30-day mortality. Nine (27.2%) of the 33 patients developed a symptomatic anastomotic leakage which was diagnosed at a median of 8 days (range 4-14) postoperatively. The serum CRP was increased in patients who leaked from postoperative day 2 onwards (P = 0.004 on day 2; P < 0.001 on day 3-8). The WBC was decreased in preoperatively irradiated patients on days 1-5 (P </= 0.021), with no difference seen between patients with or without leakage. Patients with leakage had a larger presacral fluid collection on CT on day 7 (median 76 ml vs 52 ml; P = 0.016) and a larger increase in the fluid collection between the first and the second CT examinations (28 ml vs 3 ml; P = 0.046). CONCLUSION; An early rise in serum CRP was a strong indicator of leakage. Monitoring of CRP for possible early detection of symptomatic anastomotic leakage is recommended.

Contamination of headwater streams in the United Kingdom by oestrogenic hormones from livestock farms

Most studies of hormonal activity in rivers have focused on inputs from sewage treatment works (STW), and their consequences for endocrine disruption in fish. It is possible that livestock is contributing to this hormonal activity in rivers. This study represents a search for evidence of steroid hormone contamination in streams associated with livestock farms. The majority of the 10 sites selected were streams running through dairy farms, although some examples of beef, sheep and pigs were included. Passive water samplers (Polar Organic Chemical Integrative Samplers-POCIS) were deployed up- (control) and down-stream of the farms for 3 to 10 weeks (mean=39 days) during the period November 2004 to January 2005. At one site, water samples were also taken automatically during rainfall events. All samples were solvent-extracted. Total oestrogenic activity in concentrates of the extracts was analysed using the Yeast Estrogen Screen (YES) calibrated against 17beta-oestradiol (E2), while oestrone (E1), E2 and 17alpha-ethinylestradiol (EE2) were analysed by liquid chromatography-mass spectrometry (LC-MS/MS). Stream water from the entirety of only one rainfall event was sampled directly, but this revealed background activity (E2 equivalents) of 0-0.3 ng/l, rising to a transient peak of 9.4 ng/l. Average oestrogenic activity at this site as estimated from the POCIS samplers was 1.8-2.7 ng E2 equiv./l. Estimated average oestrogenic activity across all sites (with one exception) lay in the range 0-26.5 ng E2 equiv./l (mean=2.0 ng/l; S.D.=5.1), based on the POCIS samples. The outlier was 292 ng/l, and this could not be specifically linked with livestock rearing. 92% of monitoring stations (at least one on each farm) contained some oestrogenic activity, and activity was higher at downstream sites in 50% of cases. Although no EE2 was detected analytically in any stream, E1 and E2 were almost ubiquitous, with E2 equivalents ranging from 0.04 to 3.6 ng/l across all sites. Furthermore, steroid concentrations downstream of livestock were higher than upstream in 60% of cases, more markedly so than for the YES data. In several cases, activity upstream was greater than downstream, and this tended to be associated with higher activity than could be accounted for by the hormone analyses. Both the YES and chemical analytical data suggest that fish in headwater streams on or near some livestock farms may be at risk of endocrine disruption.

The potential steroid hormone contribution of farm animals to freshwaters, the United Kingdom as a case study

The combined farm animal population is considerably larger than the human one in the United Kingdom, implying a possibly important contribution to the environmental load of steroid hormones entering water. To make comparisons on the amount of steroid hormones produced by the different livestock, information was gathered on the structure of the UK farm animal populations and the amount of hormones excreted by animals at each of their life stages. An individual normalised dairy cow excretes two orders of magnitude more, and a normalised pig excretes more than one order of magnitude more steroid oestrogens than a normalised human. In terms of excretion, the combined farm animal population (including sheep and poultry) probably generates around four times more oestrogens than the human population in the UK. The biggest contributor on the animal side is the relatively small dairy cow population. If steroid oestrogens behave like herbicides, in which a worst case loss to surface waters is around 1%, then it could be argued that farm animals are responsible for 15% of all the oestrogens in UK waters. When simulations were made with the MACRO pesticide leaching model, predicted concentrations for field drains failed to exceed 1 ng/L. The rapid biodegradation rates, and high sorption rates taken from the literature and used in the model suggested less than 0.001% of oestrogens would reach the field drains. This survey suggests that direct excretion of steroid hormones by animals into water courses, or discharges from farmyard drains, are likely to be more important sources of contamination rather than via normal agricultural scenarios.

Population-based study of risk factors for postoperative death after anterior resection of the rectum

BACKGROUND

The aim of this population-based study was to analyse risk factors for death within 30 days after anterior resection of the rectum.

METHODS

Between 1987 and 1995 a total of 6833 patients underwent elective anterior resection of the rectum in Sweden. One hundred and forty of these patients died within 30 days or during the initial hospital stay. These patients were compared with a randomly chosen cohort of 423 patients who underwent the same operation during the same interval, and were alive after 30 days and discharged from hospital. The association between death and 12 putative risk factors was studied.

RESULTS

The mortality rate after elective anterior resection was 2.1 per cent (140 of 6833). The incidence of clinical anastomotic leakage was 42.1 per cent (59 of 140) among those who died and 10.9 per cent (46 of 423) in the cohort group. Multivariate regression analysis identified clinical leakage, increased age, male sex, Dukes' 'D' stage and intraoperative adverse events as independent risk factors for death within 30 days.

CONCLUSION

Clinical anastomotic leakage was a major cause of postoperative death after anterior resection.

Intraoperative adverse events and outcome after anterior resection of the rectum

Background

The aim of this population-based study was to analyse the relationship between intraoperative adverse events and outcome after anterior resection.

Methods

All 140 patients who underwent elective anterior resection in Sweden between 1987 and 1995, and who died within 30 days, were compared with a group of 423 randomly selected patients who underwent the same procedure during the same interval but survived the operation. Intraoperative adverse events and intraoperative measures taken were analysed in relation to outcome of surgery.

Results

Of those who died, 45·7 per cent had intraoperative adverse events compared with 30·3 per cent in the cohort group. Major bleeding, gross spillage of faeces, and two or more intraoperative adverse events were more common among those who died. When the anastomosis was considered unsatisfactory, it was more frequently reconstructed (restapled or completely resutured), with or without a temporary stoma, in those who survived. The use of a temporary stoma was comparable in the two groups when adverse events were present.

Conclusion

Intraoperative adverse events were important contributors to morbidity and mortality. Complete reconstruction of an unsatisfactory anastomosis, with or without addition of a temporary stoma, was more frequently performed in the survivors, and may have diminished the risk of postoperative death.

Risk factors for anastomotic leakage after anterior resection of the rectum

OBJECTIVE

Surgical technique and peri-operative management of rectal carcinoma have developed substantially in the last decades. Despite this, morbidity and mortality after anterior resection of the rectum are still important problems. The aim of this study was to identify risk factors for anastomotic leakage in anterior resection and to assess the role of a temporary stoma and the need for urgent re-operations in relation to anastomotic leakage.

PATIENTS AND METHODS

In a nine-year period, from 1987 to 1995, a total of 6833 patients underwent elective anterior resection of the rectum in Sweden. A random sample of 432 of these patients was analysed (sample size 6.3%). The associations between death and 10 patient- and surgery-related variables were studied by univariate and multivariate analysis. Data were obtained by review of the hospital files from all patients.

RESULTS

The incidence of symptomatic clinically evident anastomotic leakage was 12% (53/432). The 30-day mortality was 2.1% (140/6833). The rate of mortality associated with leakage was 7.5%. A temporary stoma was initially fashioned in 17% (72/432) of the patients, and 15% (11/72) with a temporary stoma had a clinical leakage, compared with 12% (42/360) without a temporary stoma, not significant. Multivariate analysis showed that low anastomosis (< or = 6 cm), pre-operative radiation, presence of intra-operative adverse events and male gender were independent risk factors for leakage. The risk for permanent stoma after leakage was 25%. Females with stoma leaked in 3% compared to men with stoma who leaked in 29%. The median hospital stay for patients without leakage was 10 days (range 5-61 days) and for patients with leakage 22 days (3-110 days).

CONCLUSION

In this population based study, 12% of the patients had symptomatic anastomotic leakage after anterior resection of the rectum. Postoperative 30-day mortality was 2.1%. Low anastomosis, pre-operative radiation, presence of intra-operative adverse events and male gender were independent risk factors for symptomatic anastomotic leakage in the multivariate analysis. There was no difference in the use of temporary stoma in patients with or without anastomotic leakage.

A model for environmental sex reversal in fish

A mathematical model is presented which combines genetic XX-female/XY-male sex determination with environmental pressure for phenotypic sex reversal. This may occur when fishes are exposed to endocrine disrupters, specifically masculinization by exposure to androgens and feminization by exposure to estrogens. A generic model is derived for the sex ratio in successive generations and three special cases, with chronic and constant pressure to sex reverse, are discussed in detail. These show that, with extreme environmental pressure to masculinize, the male genotype is at risk of dying out but with less extreme pressure, masculinization will not be detectable since the proportion of phenotypic males becomes one-half. With feminization at any pressure to sex reverse, the male and female genotypes will be maintained in a stable sex ratio in which the proportion of genotypic males exceeds one-half and is close to one-half if YY offspring (eggs) are not viable. In converse, the model is also applicable to the genetic ZZ-male/ZW-female system of sex determination in fish. At present suitable data are not available with which to validate the model, but proposals are made for relevant experimental studies.

Historical perspective on endocrine disruption in wildlife

Endocrine disruption (ED) as a named field of research has been very active for over 10 years, but effects in wildlife that would now be labeled as ED have been studied since the 1940s. This paper briefly surveys the progress in wildlife studies that has been made to date and draws out the major themes and issues that have been identified. In particular, it discusses information concerning causative substances, modes of action, ubiquity of effects across taxa, individual- and population-level impacts, and the importance of low-dose and mixture effects. The main conclusion is that while most wildlife taxa are showing some ED effects at some locations, good evidence for population-level impacts is still limited to a few groups. In order to improve both the interpretation of field observations and the way in which environmental risk assessments are conducted, we need to develop an enhanced ability to predict effects on populations and communities from a knowledge of effects on individuals.

Low-dose bupivacaine plus fentanyl for spinal anesthesia during ambulatory inguinal herniorrhaphy: a comparison between 6 mg and 7. 5 mg of bupivacaine

BACKGROUND

Inguinal herniorrhaphy is commonly performed as an outpatient procedure. Spinal anesthesia offers some advantages over general anesthesia in this setting.

METHODS

Forty patients were randomly divided into two groups according to a double-blind protocol: Group L had spinal anesthesia with bupivacaine 6.0 mg and Group H with bupivacaine 7.5 mg; in both groups, fentanyl 25 micro g was added to the spinal anesthetic. The sensory block was measured by 'pin-prick' and the motor block was evaluated by a modified Bromage scale.

RESULTS

No differences were seen in the spread, duration and regression of sensory block between the groups on the operated side. A greater number of patients required analgesics during the operation in Group L (6) compared with Group H (1) (P<0.05). The return of the modified Bromage scale to grade 0 was earlier in Group L than in Group H (P<0.05) but the time to mobilization and discharge was similar. Seven patients (17%) needed to be catheterized and two had the catheter retained overnight. Times to home discharge (median) were 350 and 445 min, respectively, in Groups L and H. Postoperatively and during the first week, visual analog pain scores, analgesic requirements and side-effects were similar between the groups. In Group H, 95% of the patients and in Group L 85% would have the same anesthetic again if operated upon for a similar procedure.

CONCLUSIONS

Spinal anesthesia with bupivacaine 7.5 mg and fentanyl offers an alternative to general or local anesthesia for ambulatory inguinal herniorrhaphy. However, the long discharge times and risk for urinary retention restrict its routine use in all patients.

Safety of the temporary loop ileostomy

OBJECTIVE: To evaluate the complications of the temporary loop ileostomy. METHOD: A retrospective study of 222 consecutive patients with low anterior resection, ileal pouch-anal anastomosis or continent ileostomy and a diverting loop ileostomy routinely fashioned during the primary operation. The loop ileostomy was closed in 213 patients (96%) during the minimum follow-up period of 15 months. RESULTS: Four patients (2%) required preterm closure of the ostomy due to stomal retraction (n = 3) or bowel obstruction (n = 1). Four patients were readmitted due to transient bowel obstruction that resolved without surgery. After closure of the loop ileostomy a total of 27 patients (13%) had complications. In 7 patients emergency re-operation was done due to small bowel obstruction (n = 5) or intra-abdominal abscess (n = 2). Elective re-operation was done in 5 patients for hernia at the site of the previous stoma. Despite the use of a loop ileostomy there was 1 postoperative death after the initial operation in consequence of anastomotic leakage. There was 1 death in consequence of closure of the loop ileostomy after 3 weeks due to intra-abdominal sepsis and heart failure. CONCLUSION: In this series closure of the ostomy wasassociated with one death (0.5%) and overall ostomy-related morbidity included the need to re-operate in 6%.

Measurement of stress effects (scope for growth) and contaminant levels in mussels (Mytilus edulis) collected from the Irish Sea

The objective of this research was to quantify the impact of pollution along the coastlines of the Irish Sea. Pollution assessment was based on the combined measurement of scope for growth (SFG), and chemical contaminants in the tissues of mussels (Mytilus edulis) collected from 38 coastal sites around the Irish Sea during June-July in 1996 and 1997. On the UK mainland coast, the SFG showed a general trend with a significant decline in water quality in the Liverpool and Morecambe Bay region. High water quality was recorded along the west coast of Wales, as well as southwest England and northwest Scotland (clean reference sites outside the Irish Sea). Along the coast of Ireland there was a similar trend with reduced SFG within the Irish Sea region. SFG was generally low north of Duncannon and then improved north of Belfast. The poor water quality on both sides of the Irish Sea is consistent with the prevailing hydrodynamics and the spatial distribution of contaminants associated with urban/ industrial development. The decline in SFG of mussels on both sides of the Irish Sea was associated with a general increase in contaminant levels in the mussels. Certain contaminants, including PAHs, TBT, sigmaDDT, Dieldrin, gamma-HCH, PCBs, and a few of the metals (Cd, Se, Ag, Pb), showed elevated concentrations. Many of these contaminants were particularly elevated in the coastal margins of Liverpool Bay, Morecambe Bay and Dublin Bay. A quantitative toxicological interpretation (QTI) of the combined tissue residue chemistry and SFG measurements indicated that at the majority of coastal sites, c. 50 to > 80% of the observed decline in SFG was due to PAHs as a result of fossil fuel combustion and oil spills. TBT levels were highest at major ports and harbours, but these concentrations only made a minor contribution to the overall reduction in SFG. At no sites were individual metals accumulated to concentrations that could cause a significant effect on SFG. The study identified many sites where the observed reduction in SFG was far greater than predicted from the limited number of chemical contaminants analysed, thus indicating the presence of additional 'unknown toxicants'. Sewage (containing domestic, agricultural and industrial components) appears to be an important contributor to reduced SFG and linear alkylbenzenes (LABs) and As may provide suitable 'sewage markers'. There was a highly significant positive correlation between SFG and As (P < 0.001). This relationship may be due to reduced As uptake by algal food material and mussels at sites with elevated P04 concentrations (e.g. at sites with sewage inputs). Phosphate is a known competitive inhibitor of As accumulation, at least in algae. The results highlight that further research is required on 'sewage markers' in mussels. The SFG approach therefore provides a rapid, cost-effective and quantitative measure of pollution impact, as well as a means of identifying the causes through a QTI of tissue contaminants levels. It also serves to identify the presence of unidentified toxicants and areas that require further study.

Characterization of estrogenic compounds in water samples collected from United Kingdom estuaries

This report describes the identification of important estrogenic compounds in surface and sediment pore-water samples collected from the Tyne and Tees estuaries (United Kingdom) through the application of toxicity identification evaluation (TIE) procedures. The Tyne and Tees estuaries represent estuaries that have been historically impacted by industrial activities and continue to receive treated domestic sewage and industrial effluent. In 1998, Dabholm Gut on the Tees received a mixture of treated and untreated effluent, while Howdon sewage treatment works (STW) discharged primary treated effluents. An estrogenically active water sample collected from Howdon STW on the Tyne was shown to contain 17beta-estradiol, androsterone, and an unknown estrogenic compound(s). Most of the activity contained in a sample collected from the Dabholm Gut combined discharges on the Tees was also due to 17beta-estradiol with additional activity from nonylphenol and (tentatively) bis(2-ethylhexyl)phthalate. The only sediment pore-water sample to demonstrate estrogenic activity was collected from Dabholm Gut.

Characterization of estrogenic compounds in water samples collected from United Kingdom estuaries

This report describes the identification of important estrogenic compounds in surface and sediment pore-water samples collected from the Tyne and Tees estuaries (United Kingdom) through the application of toxicity identification evaluation (TIE) procedures. The Tyne and Tees estuaries represent estuaries that have been historically impacted by industrial activities and continue to receive treated domestic sewage and industrial effluent. In 1998, Dabholm Gut on the Tees received a mixture of treated and untreated effluent, while Howdon sewage treatment works (STW) discharged primary treated effluents. An estrogenically active water sample collected from Howdon STW on the Tyne was shown to contain 17beta-estradiol, androsterone, and an unknown estrogenic compound(s). Most of the activity contained in a sample collected from the Dabholm Gut combined discharges on the Tees was also due to 17beta-estradiol with additional activity from nonylphenol and (tentatively) bis(2-ethylhexyl)phthalate. The only sediment pore-water sample to demonstrate estrogenic activity was collected from Dabholm Gut.

Toxicity characterisation of organic contaminants in stormwaters from an agricultural headwater stream in south east England

The transient movement of pesticides at biologically active concentrations during storm events is considered to be a cause of biological impoverishment in some headwater streams. The programme of work described sought to identify compounds that are the cause of toxic effects during such events. Along with targeted pesticide analysis, toxicity identification evaluation (TIE) procedures were used to identify compounds with a demonstrated toxic effect. These procedures were specifically directed towards isolating and attributing toxicity to classes of organic contaminants in samples collected from an English headwater stream during a storm event. The organic load was isolated by means of solid-phase extraction (SPE). Bioassay of the SPE extract at x 100 whole water concentrations confirmed that the samples contained substances toxic to Daphnia magna, although the raw samples were not toxic. Targeted pesticide analysis identified simazine and diuron as the major pesticides present and, using a toxicity unit (TU) approach. were shown to be responsible for a significant amount of the observed concentrate toxicity during a runoff event. However, they were not present in sufficient quantities to be totally responsible for a more toxic later event. By simplification of the SPE isolate using reverse-phase HPLC, fractions from which were tested for toxicity, the cause of concentrate toxicity in the later event was isolated to two discrete fractions. GC-MS analysis of these fractions identified nonylphenol. endosulfan sulphate and pendimethalin as present, with the majority of toxicity attributed to nonylphenol (NP). The main advantage of the TIE approach is that it allows biological active compounds with a demonstrated effect to be identified that may not be selected by more traditional techniques.

Improvements in the epifauna of the Crouch Estuary (United Kingdom) following a decline in TBT concentrations

In the United Kingdom, the use of TBT-based anti-fouling paints on small vessels was banned in 1987, and a biological study of the Crouch Estuary, a yachting centre on the south-eastern English coastline, was initiated in order to monitor any associated changes. The macrobenthic infauna and epifauna were sampled between 1987 and 1992, and again in 1997. Epifaunal sampling in 1997 showed that an earlier increase in sedentary taxa had been sustained, and also that a large population of the native oyster Ostrea edulis had become established upstream. Multivariate analysis revealed continuance of a trend towards directional change in community composition at inner estuary stations, where TBT concentrations were historically much higher. These observations, along with evidence of established populations of a range of ascidian species in the inner estuary after an initial marked increase in densities, provide circumstantial evidence of an underlying improvement in environmental conditions following the TBT ban in 1987.